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  • Articles  (323)
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  • 1
    Publication Date: 2013-09-26
    Description: In 2005, three fishermen, with artisan fishing vessels and drift gillnets, accidentally captured around 200 dolphins between Vigia and Salinópolis in the Amazon River estuary. The dolphins died and they then prepared their vaginas and penises in order to sell them in the Ver-ao-Peso market in the city of Belem within the Brazilian state of Pará. We randomly sampled a minimal quantity of tissue of these sexual organs from 78 of these 200 dolphins and we determined the following results after sequencing 689 base pairs (bp) from the mitochondrial control region gene: (1) 96.15% (75/78) of these dolphins belonged to the species Sotalia guianensis. The other species detected were Steno brenadensis, Stenella coeruleoalba and Tursiops truncatus; (2) The levels of gene diversity found in this sample of S. guianensis were high (33 haplotypes, haplotype diversity of 0.917 and nucleotide diversity of 0.0045) compared to gene diversities found in other Brazilian S. guianensis locations; (3) All the population genetics methods employed indicated a clear population expansion in this population. This population expansion could have begun 400,000 years ago; (4) The haplotype divergence within this population could have begun around 2.1 millions of years ago (MYA), with posterior splits around 2.0–1.8 MYA, 1.7–1.8 MYA, 1–1.5 MYA, 0.6–0.8 MYA, 0.4–0.2 MYA and 0.16–0.02 MYA, all during the Pleistocene.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 2
    Publication Date: 2013-10-01
    Description: Understanding mechanisms underlying insects’ host choice and plant susceptibility is important to the study of plant-insect interactions in general, and in the context of plant invasions. This study investigates the oviposition and feeding choices of the specialist weevil Exapion ulicis on the invasive plant species Ulex europaeus, gorse. To do so, we studied the oviposition and feeding preferences of the weevil in choice experiments, using pods and flowers, respectively, from gorses grown in a common garden. The plants used came from regions with different infestation histories: Brittany and Scotland belong to the native range, where the weevil is present, while Reunion and New Zealand belong to the invasive range, where the weevil was not initially introduced with gorse. Results of these experiments suggest that the oviposition choice of E. ulicis females is driven by cues located at the surface of pods and inside them, including pod size and pod seed content. Feeding-choice experiments showed a different pattern of preference compared to oviposition. Taken together with previous studies, our results reveal that E. ulicis uses several traits to choose its host, including whole-plant traits, flower traits and pod traits.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 3
    Publication Date: 2013-03-22
    Description: The Wallacean island of Timor is of particular biological interest due to its relatively large size and transitional location between the Indo-Malayan and Australasian biogeographic realms. However, the origins and levels of endemism of its invertebrate fauna are poorly known. A recent study of Timorese ants revealed a diverse fauna with predominantly Indo-Malayan affinities, but species-level taxonomy was considered to be too poorly understood for an analysis of levels of endemism. The highly diverse Old World tropical genus Polyrhachis represents a notable exception, and here we analyse levels of endemism in the Polyrhachis fauna of Timor and surrounding islands. We supplement the species listed in the previous study with additional collections to record a total of 35 species of Polyrhachis from Timor and surrounding islands. Only 14 (40%) of the 35 species could be named (P. constricta, P. costulata, P. gab, P. sokolova, P. hera, P. illaudata, P. rixosa, P. acantha chrysophanes, P. saevissima, P. bicolor, P. cryptoceroides, P. dives, P. longipes and P. olybria), and the large majority of the remaining species have not previously been collected. These are very likely to be endemic to Timor and surrounding islands, and point to remarkably high levels (>50%) of endemism in the regional ant fauna.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 4
    Publication Date: 2013-04-03
    Description: Defining units of conservation below the species level is a widely accepted conservation priority, but is especially challenging for widespread taxa that have experienced diverse geographic histories and exist across heterogenous environments. The lake chub (Pisces: Couesius plumbeus) is a widespread freshwater fish in North America and occurs from the southcentral USA to northwestern Alaska and Canada. We used mtDNA sequence analysis to test for divergent lineages predicted to occur as a result of survival of lake chub in distinct glacial refugia. Lake chub consisted of two major mtDNA lineages separated by 3.8% sequence divergence which are probably late to pre-Pleistocene in origin. We combined these data with those consistent with thermal adaptation in fish living in thermal springs versus those living in a lake with wide seasonal temperature variation, and with data on distribution of lake chub in major watershed units. We assessed these data against objective criteria developed to identify conservation units under Canadian endangered species legislation. Our analysis identified twelve major units of conservation within C. plumbeus that could be assessed under Canada’s Species-at-Risk Act. Our study illustrates how different character traits manifested at very different spatial scales can be used to define conservation units within widely-distributed taxa.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 5
    Publication Date: 2013-09-26
    Description: Understanding the temporal and spatial scale at which habitat alteration impacts populations is important for conservation and management. Amphibians have declined more than other vertebrates, and pond-breeding species are particularly susceptible to habitat loss and fragmentation because they have terrestrial and aquatic life stages. One approach to management of pond-breeding species is protection of core upland habitat surrounding the breeding pond. We used genetic variation as an indicator of population status in a common amphibian species, spotted salamanders (Ambystoma maculatum), to determine how amount of suitable upland habitat relates to population status in the greater Charlotte, North Carolina, USA metropolitan area. We developed candidate models to evaluate the relative influence of historical and contemporary forested habitat availability on population genetic variation at two spatial scales of upland area (164 m and 2000 m) at four time intervals over the past seven decades (1938, 1978, 1993, 2005). We found that historical land cover best predicted contemporary allelic richness. Inbreeding coefficient and observed heterozygosity were not effectively predicted by forest cover at either spatial or temporal scales. Allelic richness was best predicted at the smaller spatial scale in the 1993 time interval. Predicting and understanding how future landscape configuration affects genetic variation of common and rare species is imperative for the conservation of amphibian and other wildlife populations.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 6
    Publication Date: 2014-11-07
    Description: Biological invasions of aquatic systems disrupt ecological communities, and cause major changes in diversity and ecosystem function. The Laurentian Great Lakes of North America have been dramatically altered by such invasions, especially zebra (Dreissena polymorpha) and quagga (D. rostriformis bugensis) mussels. Responses to mussel invasions have included increased water clarity, and decreased chlorophyll and phytoplankton abundance. Although not all systems have responded similarly, in general, mussels have changed nutrient dynamics and physical habitat conditions. Therefore examination of different impacts can help us further understand mechanisms that underlie ecosystem responses to biological invasions. To aid our understanding of ecosystem impacts, we sampled established locations along a well-studied trophic gradient in Green Bay, Lake Michigan, after the 1993 zebra mussel invasion. A strong trophic gradient remained during the period sampled after the mussel invasion (2000–2012). However, mean summer chlorophyll increased and other measures of phytoplankton biomass (microscope and electronic cell counting) did not change significantly. Multivariate analyses of phytoplankton community structure demonstrate a significant community shift after the invasion. Cyanobacteria increased in dominance, with Microcystis becoming the major summer taxon in lower Green Bay. Diatom diversity and abundance also increased and Chlorophyta became rare. Phytoplankton responses along the trophic gradient of Green Bay to zebra mussel invasion highlight the importance of mussel effects on nutrient dynamics and phytoplankton diversity and function.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 7
    Publication Date: 2014-12-19
    Description: There have been few assessments of the performance of alternative resistance surfaces, and little is known about how connectivity modeling approaches differ in their ability to predict organism movements. In this paper, we evaluate the performance of four connectivity modeling approaches applied to two resistance surfaces in predicting the locations of highway crossings by American black bears in the northern Rocky Mountains, USA. We found that a resistance surface derived directly from movement data greatly outperformed a resistance surface produced from analysis of genetic differentiation, despite their heuristic similarities. Our analysis also suggested differences in the performance of different connectivity modeling approaches. Factorial least cost paths appeared to slightly outperform other methods on the movement-derived resistance surface, but had very poor performance on the resistance surface obtained from multi-model landscape genetic analysis. Cumulative resistant kernels appeared to offer the best combination of high predictive performance and sensitivity to differences in resistance surface parameterization. Our analysis highlights that even when two resistance surfaces include the same variables and have a high spatial correlation of resistance values, they may perform very differently in predicting animal movement and population connectivity.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 8
    Publication Date: 2011-06-28
    Description: A comparison of the community structure of juvenile hermatypic corals of 2 to 37 m depth at the fringing reefs of Curaçao between 1975 and 2005 shows a decline of 54.7% in juvenile coral abundance and a shift in species composition. Agaricia species and Helioseris cucullata, the most common juveniles in 1975, showed the largest decline in juvenile abundance (a 9 and 120 fold decrease in density respectively) with Helioseris cucullata being nearly extirpated locally. In 2005, Porites astreoides contributed most colonies to the juvenile coral community, increasing from 8.2% (in 1975) to 19.9% of the total juvenile community. Between 1975 and 2005, juveniles of brooding species decreased in relative abundance while the abundance of juveniles of broadcast spawning species increased or remained the same. These data illustrate the magnitude of the changes that have occurred in only three decades in the composition of juvenile coral communities.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 9
    Publication Date: 2011-06-17
    Description: Landscape scale conservation planning efforts have been in place for the past several decades to maintain biodiversity. Objectives of past efforts have been to identify areas to create reserves based on species diversity, land ownership, and landscape context. Risk analysis has not often been included in these spatial analyses. Datasets such as the Southwest Regional Gap Analysis (SWReGAP) are now available as are processes that allow risk analysis to be viewed in a spatial context in relations to factors that affect habitats over broad scales. We describe a method to include four spatial datasets to provide coarse scale delineation on areas to focus conservation including species numbers, key habitats, land management and factors that influence habitats. We used the SWReGAP management status dataset to identify management categories for long-term intent of management for biodiversity. The New Mexico Department of Game and Fish identified a set of 290 Species of Greatest Conservation Need (SGCN). Species occurrences for these species were associated with hydrologic unit codes from the National Hydrography Dataset (NHD). Key habitats were identified by using the SWReGAP land cover dataset and NHD derivatives. Factors that influence habitats were identified and scored for 89 land cover types and 23 aquatic habitats identified by the NMDGF. Our final model prioritizes landscapes that are within key habitats, have high numbers of terrestrial and aquatic Species of Greatest Conservation Need taxa, may be potentially altered by multiple effects that influence habitats, and lack long-term legally-binding management plans protecting them from anthropogenic degradation. Similar to other efforts, riparian and aquatic habitats were identified as the most important for conservation. This information may be displayed spatially, allowing land managers and decision makers to understand the ecological context where multiple effects of potential factors may influence some habitats greater than others, and repeat process with CWCS revisions.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 10
    Publication Date: 2011-05-27
    Description: Environmental monitoring programs must efficiently describe state shifts. We propose using maximum entropy modeling to select dissimilar sampling sites to capture environmental variability at low cost, and demonstrate a specific application: sample site selection for the Central Plains domain (453,490 km2) of the National Ecological Observatory Network (NEON). We relied on four environmental factors: mean annual temperature and precipitation, elevation, and vegetation type. A “sample site” was defined as a 20 km × 20 km area (equal to NEON’s airborne observation platform [AOP] footprint), within which each 1 km2 cell was evaluated for each environmental factor. After each model run, the most environmentally dissimilar site was selected from all potential sample sites. The iterative selection of eight sites captured approximately 80% of the environmental envelope of the domain, an improvement over stratified random sampling and simple random designs for sample site selection. This approach can be widely used for cost-efficient selection of survey and monitoring sites.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 11
    Publication Date: 2011-05-31
    Description: This article summarises the sometimes controversial contributions made by the different sciences to predict the path of ocean acidification impacts on the diversity of coral reefs during the present century. Although the seawater carbonate system has been known for a long time, the understanding of acidification impacts on marine biota is in its infancy. Most publications about ocean acidification are less than a decade old and over half are about coral reefs. Contributions from physiological studies, particularly of coral calcification, have covered such a wide spectrum of variables that no cohesive picture of the mechanisms involved has yet emerged. To date, these studies show that coral calcification varies with carbonate ion availability which, in turn controls aragonite saturation. They also reveal synergies between acidification and the better understood role of elevated temperature. Ecological studies are unlikely to reveal much detail except for the observations of the effects of carbon dioxide springs in reefs. Although ocean acidification events are not well constrained in the geological record, recent studies show that they are clearly linked to extinction events including four of the five greatest crises in the history of coral reefs. However, as ocean acidification is now occurring faster than at any know time in the past, future predictions based on past events are in unchartered waters. Pooled evidence to date indicates that ocean acidification will be severely affecting reefs by mid century and will have reduced them to ecologically collapsed carbonate platforms by the century’s end. This review concludes that most impacts will be synergistic and that the primary outcome will be a progressive reduction of species diversity correlated with habitat loss and widespread extinctions in most metazoan phyla.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 12
    Publication Date: 2011-11-10
    Description: Classification of cattle breeds contributes to our understanding of the history of cattle and is essential for an effective conservation of genetic diversity. Here we review the various classifications over the last two centuries and compare the most recent classifications with genetic data. The classifications devised during the 19th to the late 20th century were in line with the Linnaean taxonomy and emphasized cranial or horn morphology. Subsequent classifications were based on coat color, geographic origin or molecular markers. Several theories were developed that linked breed characteristics either to a supposed ancestral aurochs subspecies or to a presumed ethnic origin. Most of the older classifications have now been discarded, but have introduced several Latin terms that are still in use. The most consistent classification was proposed in 1995 by Felius and emphasizes the geographic origin of breeds. This is largely in agreement with the breed clusters indicated by a biochemical and molecular genetic analysis, which reflect either groups of breeds with a common geographic origin or single breeds that have expanded by export and/or crossbreeding. We propose that this information is also relevant for managing the genetic diversity of cattle.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 13
    Publication Date: 2012-02-11
    Description: Micro-relief heterogeneity can lead to substantial variability in microclimate and hence niche opportunities on a small scale. We explored the relationship between plant species richness and small-scale heterogeneity of micro-relief on the subtropical island of La Palma, Canary Islands. Overall, we sampled 40 plots in laurel and pine forests at four altitudinal bands. Species richness was recorded separately for various growth forms (i.e., mosses, herbaceous and woody plants). Site conditions such as altitude, slope, aspect, and tree density were measured. Micro-relief heterogeneity was characterized by surface structure and a subsequently derived surface heterogeneity index. The effect of micro-relief heterogeneity on species richness was analysed by means of linear mixed effect models and variance partitioning. Effects of micro-relief heterogeneity on species richness varied considerably between growth forms. While moss richness was affected significantly by micro-relief heterogeneity, herbaceous and woody plants richness responded mainly to larger-scale site conditions such as aspect and tree density. Our results stress the importance of small-scale relief heterogeneity for the explanation of spatial patterns of species richness. This poses new challenges as small-scale heterogeneity is largely underrepresented, e.g. with regard to its application in species distribution models.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 14
    Publication Date: 2013-02-22
    Description: Identifying a soil core microbiome is crucial to appreciate the established microbial consortium, which is not usually subjected to change and, hence, possibly resistant/resilient to disturbances and a varying soil context. Fungi are a major part of soil biodiversity, yet the mechanisms driving their large-scale ecological ranges and distribution are poorly understood. The degree of fungal community overlap among 16 soil samples from distinct ecosystems and distant geographic localities (truffle grounds, a Mediterranean agro-silvo-pastoral system, serpentine substrates and a contaminated industrial area) was assessed by examining the distribution of fungal ITS1 and ITS2 sequences in a dataset of 454 libraries. ITS1 and ITS2 sequences were assigned to 1,660 and 1,393 Operational Taxonomic Units (OTUs; as defined by 97% sequence similarity), respectively. Fungal beta-diversity was found to be spatially autocorrelated. At the level of individual OTUs, eight ITS1 and seven ITS2 OTUs were found in all soil sample groups. These ubiquitous taxa comprised generalist fungi with oligotrophic and chitinolytic abilities, suggesting that a stable core of fungi across the complex soil fungal assemblages is either endowed with the capacity of sustained development in the nutrient-poor soil conditions or with the ability to exploit organic resources (such as chitin) universally distributed in soils.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 15
    Publication Date: 2012-12-11
    Description: Unicellular saprobic fungi (yeasts) inhabit soils worldwide. Although yeast species typically occupy defined areas on the biome scale, their distribution patterns within a single type of vegetation, such as forests, are more complex. In order to understand factors that shape soil yeast communities, soils collected underneath decaying wood logs and under forest litter were analyzed. We isolated and identified molecularly a total of 25 yeast species, including three new species. Occurrence and distribution of yeasts isolated from these soils provide new insights into ecology and niche specialization of several soil-borne species. Although abundance of typical soil yeast species varied among experimental plots, the analysis of species abundance and community composition revealed a strong influence of wood log deposition and leakage of organic carbon. Unlike soils underneath logs, yeast communities in adjacent areas harbored a considerable number of transient (phylloplane-related) yeasts reaching 30% of the total yeast quantity. We showed that distinguishing autochthonous community members and species transient in soils is essential to estimate appropriate effects of environmental factors on soil fungi. Furthermore, a better understanding of species niches is crucial for analyses of culture-independent data, and may hint to the discovery of unifying patterns of microbial species distribution.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 16
    Publication Date: 2012-12-15
    Description: The practice of adding organic amendments to crop soils is undergoing resurgence as an efficient way to restore soil organic matter content and to improve soil quality. The quantity and quality of the organic matter inputs affect soil physicochemical properties and soil microbiota, influencing different parameters such as microbial biomass and diversity, community structure and microbial activities or functions. The influence of organic amendments on soil quality has also effects on crop production and plant health. The enhancement of soil suppressiveness using organic amendments has been widely described, especially for soil-borne diseases. However, there is great variability in the effectiveness of suppression depending on the nature of the amendment, the crop, the pathogen, and the environmental conditions. Although the effects of organic amendments on soil properties have been widely studied, relationships between these properties and soil suppressiveness are not still well understood. Changes in soil physicochemical parameters may modulate the efficacy of suppression. However, the parameters more frequently associated to disease suppression appear to be related to soil microbiota, such as microbial biomass and activity, the abundance of specific microbial groups and some hydrolytic activities. This review focuses on the effect of organic amendments on soil microbial populations, diversity and activities; their ability to enhance plant health through disease suppression; and which of the parameters affected by the organic amendments are potentially involved in soil suppressiveness.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 17
    Publication Date: 2013-02-19
    Description: The predominant analytical approach to associate landscape patterns with gene flow processes is based on the association of cost distances with genetic distances between individuals. Mantel and partial Mantel tests have been the dominant statistical tools used to correlate cost distances and genetic distances in landscape genetics. However, the inherent high correlation among alternative resistance models results in a high risk of spurious correlations using simple Mantel tests. Several refinements, including causal modeling, have been developed to reduce the risk of affirming spurious correlations and to assist model selection. However, the evaluation of these approaches has been incomplete in several respects. To demonstrate the general reliability of the causal modeling approach with Mantel tests, it must be shown to be able to correctly identify a wide range of landscape resistance models as the correct drivers relative to alternative hypotheses. The objectives of this study were to (1) evaluate the effectiveness of the originally published causal modeling framework to support the correct model and reject alternative hypotheses of isolation by distance and isolation by barriers and to (2) evaluate the effectiveness of causal modeling involving direct competition of all hypotheses to support the correct model and reject all alternative landscape resistance models. We found that partial Mantel tests have very low Type II error rates, but elevated Type I error rates. This leads to frequent identification of support for spurious correlations between alternative resistance hypotheses and genetic distance, independent of the true resistance model. The frequency in which this occurs is directly related to the degree of correlation between true and alternative resistance models. We propose an improvement based on the relative support of the causal modeling diagnostic tests.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 18
    Publication Date: 2013-02-01
    Description: Land-use degradation and climate change are well-known drivers of biodiversity loss, but little information is available about their potential interaction. Here, we focus on the effects of land-use and precipitation on ant diversity in cacao agroforestry. In Central Sulawesi, Indonesia, we selected 16 cacao agroforestry plots with a shaded vs. unshaded plot in each of eight villages differing in precipitation (1032–2051 mm annual rainfall). On each plot, 10 cacao trees with similar size and age (7–10 years) were selected for hand collection of ants on each cacao tree and the soil surface. In total, we found 80 ant species belonging to five subfamilies. Land-use intensification (removal of shade trees) and precipitation had no effect on species richness of ants per cacao tree (alpha diversity) and, in an additive partitioning approach, within-plot beta diversity. However, higher precipitation (but not shade) significantly increased ant species dissimilarity across cacao trees within a plot, with ant species showing contrasting responses to precipitation. Reduced precipitation causing drought stress appeared to contribute to convergence of ant community structure, presumably via reduced heterogeneity in cacao tree growth. In conclusion, reduced precipitation greatly influenced ant community dissimilarity and appeared to be more important for ant community structure than land-use intensification.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 19
    Publication Date: 2013-02-05
    Description: In the terrestrial environment, endemic species and isolated populations of widespread species have the highest rates of extinction partly due to their low genetic diversity. To determine if this pattern holds in the marine environment, we examined genetic diversity in endemic coral reef angelfishes and isolated populations of widespread species. Specifically, this study tested the prediction that angelfish (genus: Centropyge) populations at Christmas and Cocos Islands have low genetic diversity. Analyses of a 436 base pair fragment of the mtDNA control region revealed that the endemic C. joculator exhibited high haplotype (h > 0.98 at both locations) and nucleotide (Christmas p% = 3.63, Cocos p% = 9.99) diversity. Similarly, isolated populations of widespread angelfishes (C. bispinosa and C. flavicauda) had high haplotype (h > 0.98) and nucleotide (p% = 2.81 and p% = 5.78%, respectively) diversity. Therefore, in contrast to terrestrial patterns, endemic and isolated populations of widespread angelfishes do not have low genetic diversity, rather their haplotype and nucleotide diversities were among the highest reported for marine fishes. High genetic diversity should reduce extinction risk in these species as it could provide the evolutionary potential to adapt to the rapidly changing environmental conditions forecast for coral reefs.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 20
    Publication Date: 2012-09-01
    Description: The distribution and species assembly of Japanese Protura collected from forest soils were examined using published databases and statistical analysis. We used records from 3110 sites where 71 taxa were found. The species richness of Protura ranged from one to 16 species, and TWINSPAN analysis of regional populations indicated that the northern and southern regions could be separated into distinct groups. Three major species assemblages were identified by cluster analysis from points containing more than six species. Three groups reflected historical migration from northern and western linkages to the Asian continent. The northern assemblage showed a negative correlation to winter minimum temperature and the other two assemblages exhibited relationships to precipitation and temperature. Vegetation was not responsible for proturan distribution. These results suggest that the history of Protura invasion explains the biogeography of these soil-based, small arthropods and also that climate change will induce a shift in the distribution of species irrespective of changes in vegetation type.
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  • 21
    Publication Date: 2012-06-15
    Description: Wild barley [Hordeum vulgare ssp. spontaneum (C. Koch) Thell.] is a part of the primary gene pool with valuable sources of beneficial genes for barley improvement. This study attempted to develop a core subset of 269 accessions representing 16 countries from the Plant Gene Resources of Canada (PGRC) collection of 3,782 accessions, and to characterize them using barley simple sequence repeat (SSR) markers. Twenty-five informative primer pairs were applied to screen all samples and 359 alleles were detected over seven barley chromosomes. Analyses of the SSR data showed the effectiveness of the stratified sampling applied in capturing country-wise SSR variation. The frequencies of polymorphic alleles ranged from 0.004 to 0.708 and averaged 0.072. More than 24% or 7% SSR variation resided among accessions of 16 countries or two regions, respectively. Accessions from Israel and Jordan were genetically most diverse, while accessions from Lebanon and Greece were most differentiated. Four and five optimal clusters of accessions were obtained using STRUCTURE and BAPS programs and partitioned 16.3% and 20.3% SSR variations, respectively. The five optimal clusters varied in size from 15 to 104 and two clusters had only country-specific accessions. A genetic separation was detected between the accessions east and west of the Zagros Mountains only at the country, not the individual, level. These SSR patterns enhance our understanding of the wild barley gene pool, and are significant for conserving wild barley germplasm and exploring new sources of useful genes for barley improvement.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 22
    Publication Date: 2012-05-03
    Description: Assessing biodiversity and the spatial structures of forest ecosystems are important for forestry and nature conservation. However, tropical forests of Bangladesh are only sparsely investigated. Here we determined biodiversity (alpha, beta and gamma), spatial species turnover and stand characteristics of one of the few remnant tropical forests in Bangladesh. Two differently protected areas of Satchari forest were compared. We recorded tree species composition, in a systematic plot design, measured diameter at breast height for each individual tree (to assess basal area), and calculated decay in similarity of tree species composition with geographical distance. The distance-decay was assessed separately for the whole study area and for two subsamples from Satchari National Park and Satchari Reserve Forest. Satchari National Park (strictly protected) had, despite its smaller area, a higher Alpha and Gamma diversity, but a lower Beta diversity than Satchari Reserve Forest. Variation in species composition was not significant between the two differently protected areas. Basal area increased significantly with protection status although tree individuals were of equal size in both areas. Plots in the Reserve Forest were associated with higher species turnover than in the National Park. We suggest anthropogenic disturbance, which occurs in the less strictly protected Reserve Forest, is the main driver for the detected spatial heterogeneity in species composition.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 23
    Publication Date: 2012-05-03
    Description: Coral reef ecosystems are increasingly subject to severe, large-scale disturbances caused by climate change (e.g., coral bleaching) and other more direct anthropogenic impacts. Many of these disturbances cause coral loss and corresponding changes in habitat structure, which has further important effects on abundance and diversity of coral reef fishes. Declines in the abundance and diversity of coral reef fishes are of considerable concern, given the potential loss of ecosystem function. This study explored the effects of coral loss, recorded in studies conducted throughout the world, on the diversity of fishes and also on individual responses of fishes within different functional groups. Extensive (〉60%) coral loss almost invariably led to declines in fish diversity. Moreover, most fishes declined in abundance following acute disturbances that caused 〉10% declines in local coral cover. Response diversity, which is considered critical in maintaining ecosystem function and promoting resilience, was very low for corallivores, but was much higher for herbivores, omnivores and carnivores. Sustained and ongoing climate change thus poses a significant threat to coral reef ecosystems and diversity hotspots are no less susceptible to projected changes in diversity and function.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 24
    Publication Date: 2012-05-03
    Description: Adaptation of reef corals to climate change is an issue of much debate, and often viewed as too slow a process to be of relevance over decadal time scales. This notion is based on the long sexual generation times typical for some coral species. However, the importance of somatic mutations during asexual reproduction and growth on evolution and adaptation (i.e., cell lineage selection) is rarely considered. Here we review the existing literature on cell lineage selection and show that the scope for somatic mutations to arise in the coral animal and associated Symbiodinium is large. For example, we estimate that ~100 million somatic mutations can arise within a branching Acropora coral colony of average size. Similarly, the large population sizes and rapid turn-over times of in hospite Symbiodinium likely result in considerable numbers of somatic mutations. While the fate of new mutations depends on many factors, including ploidy level and force and direction of selection, we argue that they likely play a key role in the evolution of reef corals.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 25
    Publication Date: 2012-05-03
    Description: The co-occurrence of cryptic species of Hyalella amphipods is a challenge to our traditional views of how species assemble. Since these species have similar morphologies, it is not evident that they have developed phenotypic differences that would allow them to occupy different ecological niches. We examined the structure of a community of Hyalella amphipods in the littoral zone of a boreal lake to verify if temporal variation was present in relative abundances. Morphological and molecular analyses using the mitochondrial cytochrome c oxidase I (COI) gene enabled us to detect three cryptic species at the study site. No temporal variation was observed in the community, as one cryptic species was always more abundant than the two others. The relative abundances of each species in the community appeared constant at least for the open-water season, both for adult and juvenile amphipods. Niche differences are still to be found among these species, but it is suggested that migration from nearby sites may be an important factor explaining the species co-occurrence.
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  • 26
    Publication Date: 2012-05-03
    Description: Symbioses between microbes and higher organisms underpin high diversity in many ecosystems, including coral reefs, however mechanisms underlying the early establishment of symbioses remain unclear. Here we examine the roles of Symbiodinium type and cell surface recognition in the establishment of algal endosymbiosis in the reef-building coral, Acropora tenuis. We found 20–70% higher infection success (proportion of larvae infected) and five-fold higher Symbiodinium abundance in larvae exposed to ITS-1 type C1 compared to ITS-1 type D in the first 96 h following exposure. The highest abundance of Symbiodinium within larvae occurred when C1-type cells were treated with enzymes that modified the 40–100 kD glycome, including glycoproteins and long chain starch residues. Our finding of declining densities of Symbiodinium C1 through time in the presence of intact cell surface molecules supports a role for cell surface recognition molecules in controlling post-phagocytosis processes, leading to rejection of some Symbiodinium types in early ontogeny. Reductions in the densities of unmodified C1 symbionts after 96 h, in contrast to increases in D symbionts may suggest the early initiation of a winnowing process contributing to the establishment of Symbiodinium D as the dominant type in one-month old juveniles of A. tenuis.
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  • 27
    Publication Date: 2012-05-03
    Description: Hairy prairie-clover [Dalea villosa (Nutt.) Spreng. var. villosa] is a threatened Canadian wildflower. To facilitate the efforts of conserving this threatened plant, amplified fragment length polymorphism (AFLP) technique was applied to assess genetic diversity in a remnant hairy prairie-clover population in the Canadian Prairie. Three AFLP primer pairs were employed to genotype 610 individual plants from the population and 15 plants from a North Dakota composite population, and 100 polymorphic AFLP bands were analyzed. The assayed plants displayed 23% AFLP variation present between the remnant population and the North Dakota composite population, but maintained a high level (91%) of AFLP variation within patches of the remnant population. The individual genetic distinctiveness measured by average AFLP dissimilarity was positively associated with latitude and negatively with elevation. The among-patch AFLP variation was significantly related to inter-patch distance, indicating local genetic differentiation within the remnant population. However, the proportions of within-patch AFLP variation were not associated with any patch characteristics assessed (i.e., patch size, perimeter, nearest neighbor distance, mean inter-patch distance). No fine-scale genetic structure was found within three large patches, suggesting little genetic correlations present for plants five meters apart. Some genetically distinctive and diverse patches were also identified. These findings indicate that the genetic risk of the remnant hairy prairie-clover population in the Canadian Prairie is low.
    Electronic ISSN: 1424-2818
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  • 28
    Publication Date: 2012-05-03
    Description: Landscape scale conservation planning efforts have been in place for the past several decades to maintain biodiversity. Objectives of past efforts have been to identify areas to create reserves based on species diversity, land ownership, and landscape context. Risk analysis has not often been included in these spatial analyses. Datasets such as the Southwest Regional Gap Analysis (SWReGAP) are now available as are processes that allow risk analysis to be viewed in a spatial context in relations to factors that affect habitats over broad scales. We describe a method to include four spatial datasets to provide coarse scale delineation on areas to focus conservation including species numbers, key habitats, land management and factors that influence habitats. We used the SWReGAP management status dataset to identify management categories for long-term intent of management for biodiversity. The New Mexico Department of Game and Fish identified a set of 290 Species of Greatest Conservation Need (SGCN). Species occurrences for these species were associated with hydrologic unit codes from the National Hydrography Dataset (NHD). Key habitats were identified by using the SWReGAP land cover dataset and NHD derivatives. Factors that influence habitats were identified and scored for 89 land cover types and 23 aquatic habitats identified by the NMDGF. Our final model prioritizes landscapes that are within key habitats, have high numbers of terrestrial and aquatic Species of Greatest Conservation Need taxa, may be potentially altered by multiple effects that influence habitats, and lack long-term legally-binding management plans protecting them from anthropogenic degradation. Similar to other efforts, riparian and aquatic habitats were identified as the most important for conservation. This information may be displayed spatially, allowing land managers and decision makers to understand the ecological context where multiple effects of potential factors may influence some habitats greater than others, and repeat process with CWCS revisions.
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  • 29
    Publication Date: 2012-05-03
    Description: This article summarises the sometimes controversial contributions made by the different sciences to predict the path of ocean acidification impacts on the diversity of coral reefs during the present century. Although the seawater carbonate system has been known for a long time, the understanding of acidification impacts on marine biota is in its infancy. Most publications about ocean acidification are less than a decade old and over half are about coral reefs. Contributions from physiological studies, particularly of coral calcification, have covered such a wide spectrum of variables that no cohesive picture of the mechanisms involved has yet emerged. To date, these studies show that coral calcification varies with carbonate ion availability which, in turn controls aragonite saturation. They also reveal synergies between acidification and the better understood role of elevated temperature. Ecological studies are unlikely to reveal much detail except for the observations of the effects of carbon dioxide springs in reefs. Although ocean acidification events are not well constrained in the geological record, recent studies show that they are clearly linked to extinction events including four of the five greatest crises in the history of coral reefs. However, as ocean acidification is now occurring faster than at any know time in the past, future predictions based on past events are in unchartered waters. Pooled evidence to date indicates that ocean acidification will be severely affecting reefs by mid century and will have reduced them to ecologically collapsed carbonate platforms by the century’s end. This review concludes that most impacts will be synergistic and that the primary outcome will be a progressive reduction of species diversity correlated with habitat loss and widespread extinctions in most metazoan phyla.
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  • 30
    Publication Date: 2012-05-03
    Description: The paper describes rich, a new R package to perform species richness estimation and comparison. Species richness is the simplest surrogate for the more complex concept of species biodiversity. It is relatively easy to assess although estimations strongly depend on sampling intensity with the consequence that richness estimations should be standardized to perform valid comparisons. The R package rich allows such corrections as well as the computation of various statistics and implements different randomization tests to compare cumulative and average species richness of two communities. These tests are useful for ranking sites or communities which is a classical goal in restoration ecology and conservation biology.
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  • 31
    Publication Date: 2012-04-21
    Description: Written for anyone interested in green development—including policy makers, architects, developers, builders, and homeowners—this practical guide focuses on the central question of how to conserve biodiversity in neighborhoods and to minimize development impacts on surrounding habitats. The Green Leap specifically helps move green development beyond the design stage by thoroughly addressing construction and post-construction issues. [...]
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  • 32
    Publication Date: 2012-04-25
    Description: In forest ecosystems, fungal mats are functionally important in nutrient and water uptake in litter and wood decomposition processes, in carbon resource allocation, soil weathering and in cycling of soil resources. Fungal mats can occur abundantly in forests and are widely distributed globally. We sampled ponderosa pine/white fir and mountain hemlock/noble fir communities at Crater Lake National Park for mat-forming soil fungi. Fungus collections were identified by DNA sequencing. Thirty-eight mat-forming genotypes were identified; members of the five most common genera (Gautieria, Lepiota, Piloderma, Ramaria, and Rhizopogon) comprised 67% of all collections. The mycorrhizal genera Alpova and Lactarius are newly identified as ectomycorrhizal mat-forming taxa, as are the saprotrophic genera Flavoscypha, Gastropila, Lepiota and Xenasmatella. Twelve typical mat forms are illustrated, representing both ectomycorrhizal and saprotrophic fungi that were found. Abundance of fungal mats was correlated with higher soil carbon to nitrogen ratios, fine woody debris and needle litter mass in both forest ecotypes. Definitions of fungal mats are discussed, along with some of the challenges in defining what comprises a fungal “mat”.
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  • 33
    Publication Date: 2012-05-03
    Description: Analysis was made of 3,923 records of 162 wild Passiflora specimens to assess the distribution of their diversity in Colombia, identify collection gaps, and explore their potential as indicator species. Despite variable collecting density among and within biogeographic regions, the Andean region clearly presents a higher species richness, particularly in the central coffee growing zone and the departments of Antioquia, Cundinamarca and Valle del Cauca. The elevational distribution of diversity shows a small peak below 500 m, and two higher ones between 1,000–2,000 and 2,500–3,000 m. This pattern corresponds to divergent adaptive trends among infrageneric divisions. The analysis on 19 climatic variables showed that the two principal variance components, explaining 77 percent of the total, are respectively associated with temperature and precipitation, without influence of seasonality. Distribution parameters allow recognizing more than 36 narrow endemics. Prediction of species distribution showed nine areas with very high richness (predicted sympatry of 41 to 54 species) in the Andean region, three of which correspond to collection gaps. Endemics were not particularly frequent there, so a prioritization of protected areas based on species richness would not favor their conservation. The sites with high Passiflora diversity are poorly represented in the current system of protected areas. Instead, their striking correspondence with ecotopes of the coffee growing zone imposes a conservation strategy integrating agricultural and environmental management at the landscape level. Reciprocally, several traits of Passiflora species make them particularly suited as indicators for any effort of conservation or restoration in this region of importance for the country.
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  • 34
    Publication Date: 2012-05-03
    Description: Public participation is a key element in nature conservation in Europe and a necessity for collecting broad scale data on biodiversity and its dynamics. However, vast societal differences exist between eastern and western European countries, resulting in problems for public participation in post-communist states as compared to western countries. Here, we compare diversity in monitoring practices and public participation in countries with different political histories. Drawing on in-depth ethnographic studies conducted in Lithuania and Poland, as well as a rapid assessment in Denmark, we have focused on the historical, cultural and social determinants of the volunteers’ participation in biodiversity monitoring. Our results indicate the reasons why volunteer involvement—as an expression of a participatory approach—has a lower incidence in the post-communist countries, compared to voluntarism common in occidental democracies. We discuss our results in the context of the main social factors considered to be a legacy of the Soviet regime.
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  • 35
    Publication Date: 2012-05-03
    Description: Humans harbor distinct commensal microbiota at various anatomic sites. There has been renewed interest in the contributions of microbiota activities to human health and disease. The microbiota of the gut is the most complex of all anatomic sites in terms of total numbers of bacteria that interact closely with the mucosal immune system and contribute various functions to host physiology. Especially in the proximal large intestine a diverse microbiota ferments complex substrates such as dietary fiber and host mucins, but also metabolizes bile acids and phytoestrogens that reach the large intestine. It is now well established that microbiota composition differs between but over time also within individuals. However, a thorough understanding of the sources of variations in microbiota composition, which is an important requirement for large population based microbiota studies is lacking. Microbiota composition varies depending on what kind of sample is collected, most commonly stool samples, stool swabs or superficial rectal or intestinal biopsies, and the time of collection. Microbiota dynamics are affected by life style factors including diet and exercise that determine what nutrients reach the proximal colon and how fast these nutrients pass through (transit time). Here we review sample collection issues in gut microbiota studies and recent findings about dynamics in microbiota composition. We recommend standardizing human microbiota analysis methods to facilitate comparison and pooling between studies. Finally, we outline a need for prospective microbiota studies in large human cohorts.
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  • 36
    Publication Date: 2012-05-03
    Description: Intense conversion of bottomland hardwood forests to rice and soybeans in the Mississippi River Valley of Arkansas has restricted the remaining forest to isolated fragments. Habitat fragmentation has proven to be detrimental to population sustainability of several species, and is the subject of intense study with often species and latitude specific responses. We compared both coarse land area classes and landscape fragmentation metrics from six 30 km × 30 km subsets centered on publicly owned management areas to bat captures obtained from a 2005 population study. Patch density was the strongest predictor of total captures (R2 = 0.801, p = 0.016) and of Myotis austroriparius captures (R2 = 0.856, p = 0.008). Our findings indicate that patch density and area are important predictors of bottomland bat captures.
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  • 37
    Publication Date: 2012-05-03
    Description: The high level of conservation of 16S ribosomal RNA gene (16S rRNA) in all Prokaryotes makes this gene an ideal tool for the rapid identification and classification of these microorganisms. Databases such as the Ribosomal Database Project II (RDP-II) and the Greengenes Project offer access to sets of ribosomal RNA sequence databases useful in identification of microbes in a culture-independent analysis of microbial communities. However, these databases do not contain all of the taxonomic levels attached to the published names of the bacterial and archaeal sequences. TaxCollector is a set of scripts developed in Python language that attaches taxonomic information to all 16S rRNA sequences in the RDP-II and Greengenes databases. These modified databases are referred to as TaxCollector databases, which when used in conjunction with BLAST allow for rapid classification of sequences from any environmental or clinical source at six different taxonomic levels, from domain to species. The TaxCollector database prepared from the RDP-II database is an important component of a new 16S rRNA pipeline called PANGEA. The usefulness of TaxCollector databases is demonstrated with two very different datasets obtained using samples from a clinical setting and an agricultural soil. The six TaxCollector scripts are freely available on http://taxcollector.sourceforge.net and on http://www.microgator.org.
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  • 38
    Publication Date: 2012-05-03
    Description: In western countries, one of the challenges facing ageing populations is an absence of social roles. One response to this is to volunteer, with evidence suggesting that this assigns meaning to the lives of older people and enhances health and well-being. This holds potential significance for older people from diverse cultural and linguistic backgrounds, and particularly those from Asian cultures, where there is evidence that cultural erosion is diminishing older people’s traditional roles. However, while volunteering can create role identities for older people, it may also further challenge existing cultural values. This paper debates these issues, drawing on a growing body of evidence relating to volunteering within Asian cultures.
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  • 39
    Publication Date: 2012-05-03
    Description: This report is a review of some of the results obtained over the course of 20 years spent investigating hemoglobin phenotypes and the related functional effects on hematological patterns in ruminant breeds. Tests included qualitative and quantitative analyses of hemoglobins and qualitative and quantitative analyses of α and β globins, as well as hemochromocytometric analysis. Understanding the adaptive significance of the hemoglobin variants was the goal of most of these investigations. The advances presented in this review and the previously unpublished findings included here provide evidence that Mediterranean breeds exhibit a fair number of positively charged variants, whose possible adaptive significance is discussed.
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  • 40
    Publication Date: 2012-05-03
    Description: Although the Neotropics are recognized as a region rich in biological diversity, the origin, evolution, and maintenance of this phenomenon continues to be debated. Historical ecologists and landscape archaeologists point out that the Neotropics have a long, complex human history that may have been a key factor in the creation, shaping, and management of present day biodiversity. The construction of monumental earthworks referred to as ring ditches of the Bolivian Amazon and surrounding regions in late prehistory had considerable impact on the fauna, flora, soils, and topography of forest islands. Patterned landscape features, historical documents, energetics, and historical ecology are used to understand the transformation of forest islands into anthropogenic built environments.
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  • 41
    Publication Date: 2012-05-03
    Description: Variation in individual density may explain the unimodal richness-biomass relationship in which species richness peaks at an intermediate level of total biomass. However, it is unclear how individual density is regulated by community thinning (i.e., mortality due to competition with neighbors) as total above-ground biomass increases. We developed a simulation model which demonstrates that the spatial structure of a population can influence the initiation and rate of community thinning and thus the shape of the richness-biomass relationship. Specifically, we found that more clustered populations resulted in a more abrupt initiation and rapid rate of thinning and thus a sharper unimodal richness-biomass relationship. Our simulation also demonstrated that a wide diversity of richness-biomass relationships can be produced by community-thinning.
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  • 42
    Publication Date: 2012-05-03
    Description: We used near-term climate scenarios for the continental United States, to model 12 invasive plants species. We created three potential habitat suitability models for each species using maximum entropy modeling: (1) current; (2) 2020; and (3) 2035. Area under the curve values for the models ranged from 0.92 to 0.70, with 10 of the 12 being above 0.83 suggesting strong and predictable species-environment matching. Change in area between the current potential habitat and 2035 ranged from a potential habitat loss of about 217,000 km2, to a potential habitat gain of about 133,000 km2.
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  • 43
    Publication Date: 2012-05-03
    Description: Molecular analysis of the bacterial community structure associated with sludge processed by autothermal thermophilic aerobic digestion (ATAD), was performed using a number of extraction and amplification procedures which differed in yield, integrity, ability to amplify extracted templates and specificity in recovering species present. Interference to PCR and qPCR amplification was observed due to chelation, nuclease activity and the presence of thermolabile components derived from the ATAD sludge. Addition of selected adjuvant restored the ability to amplify community DNA, derived from the thermophilic sludge, via a number of primer sets of ecological importance and various DNA polymerases. Resolution of community profiles by molecular techniques was also influenced by the ATAD sludge extraction procedure as demonstrated by PCR-DGGE profiling and comparison of taxonomic affiliations of the most predominant members within 16S rRNA gene libraries constructed from ATAD DNA extracted by different methods. Several modifications have been shown to be necessary to optimize the molecular analysis of the ATAD thermal niche which may have general applicability to diversity recovery from similar environments.
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  • 44
    Publication Date: 2012-05-03
    Description: Complex systems science has contributed to our understanding of ecology in important areas such as food webs, patch dynamics and population fluctuations. This has been achieved through the use of simple measures that can capture the difference between order and disorder and simple models with local interactions that can generate surprising behaviour at larger scales. However, close examination reveals that commonly applied definitions of complexity fail to accommodate some key features of ecological systems, a fact that will limit the contribution of complex systems science to ecology. We highlight these features of ecological complexity—such as diversity, cross-scale interactions, memory and environmental variability—that continue to challenge classical complex systems science. Further advances in these areas will be necessary before complex systems science can be widely applied to understand the dynamics of ecological systems.
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  • 45
    Publication Date: 2012-05-03
    Description: The southwestern highlands forests of Ethiopia are the origin of the coffee plant Coffea arabica. The production of coffee in this area is affected by tracheomycosis caused by a soil-born fungus Gibberella xylarioides. The use of endemic antagonistic strains of mycoparasitic Trichoderma species would be a nature conserving means to combat this disease. We have used molecular methods to reveal that the community of Trichoderma in the rhizosphere of C. arabica in its native forests is highly diverse and includes many putatively endemic species. Among others, the putative new species were particularly efficient to inhibit growth of G. xylarioides.
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  • 46
    Publication Date: 2012-05-03
    Description: A better knowledge of factors organizing crop genetic diversity in situ increases the efficiency of diversity analyses and conservation strategies, and requires collaboration between social and biological disciplines. Four areas of anthropology may contribute to our understanding of the impact of social factors on crop diversity: ethnobotany, cultural, cognitive and social anthropology. So far, most collaborative studies have been based on ethnobotanical methods, focusing on farmers’ individual motivations and actions, and overlooking the effects of farmer’s social organization per se. After reviewing common shortcomings in studies on sorghum and maize, this article analyzes how social anthropology, through the analysis of intermarriage, residence and seed inheritance practices, can contribute to studies on crop genetic diversity in situ. Crop varieties are thus considered social objects and socially based sampling strategies can be developed. Such an approach is justified because seed exchange is built upon trust and as such seed systems are embedded in a pre-existing social structure and centripetally oriented as a function of farmers’ social identity. The strong analogy between farmers’ cultural differentiation and crop genetic differentiation, both submitted to the same vertical transmission processes, allows proposing a common methodological framework for social anthropology and crop population genetics, where the classical interaction between genetic and environmental factors, G × E, is replaced by a three-way interaction G × E × S, where “S” stands for the social differentiation factors.
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  • 47
    Publication Date: 2012-05-03
    Description: While aboveground biomass and forest productivity can vary over abiotic gradients (e.g., temperature and moisture gradients), biotic factors such as biodiversity and tree species stand dominance can also strongly influence biomass accumulation. In this study we use a permanent plot network to assess variability in aboveground carbon (C) flux in forest tree annual aboveground biomass increment (ABI), tree aboveground net primary productivity (ANPPtree), and net soil CO2 efflux in relation to diversity of coniferous, deciduous, and a nitrogen (N)-fixing tree species (Alnus rubra). Four major findings arose: (1) overstory species richness and indices of diversity explained between one third and half of all variation in measured aboveground C flux, and diversity indices were the most robust models predicting measured aboveground C flux; (2) trends suggested decreases in annual tree biomass increment C with increasing stand dominance for four of the five most abundant tree species; (3) the presence of an N-fixing tree species (A. rubra) was not related to changes in aboveground C flux, was negatively related to soil CO2 efflux, and showed only a weak negative relationship with aboveground C pools; and (4) stands with higher overstory richness and diversity typically had higher soil CO2 efflux. Interestingly, presence of the N-fixing species was not correlated with soil inorganic N pools, and inorganic N pools were not correlated with any C flux or pool measure. We also did not detect any strong patterns between forest tree diversity and C pools, suggesting potential balancing of increased C flux both into and out of diverse forest stands. These data highlight variability in second-growth forests that may have implications for overstory community drivers of C dynamics.
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  • 48
    Publication Date: 2012-05-03
    Description: Micro-relief heterogeneity can lead to substantial variability in microclimate and hence niche opportunities on a small scale. We explored the relationship between plant species richness and small-scale heterogeneity of micro-relief on the subtropical island of La Palma, Canary Islands. Overall, we sampled 40 plots in laurel and pine forests at four altitudinal bands. Species richness was recorded separately for various growth forms (i.e., mosses, herbaceous and woody plants). Site conditions such as altitude, slope, aspect, and tree density were measured. Micro-relief heterogeneity was characterized by surface structure and a subsequently derived surface heterogeneity index. The effect of micro-relief heterogeneity on species richness was analysed by means of linear mixed effect models and variance partitioning. Effects of micro-relief heterogeneity on species richness varied considerably between growth forms. While moss richness was affected significantly by micro-relief heterogeneity, herbaceous and woody plants richness responded mainly to larger-scale site conditions such as aspect and tree density. Our results stress the importance of small-scale relief heterogeneity for the explanation of spatial patterns of species richness. This poses new challenges as small-scale heterogeneity is largely underrepresented, e.g. with regard to its application in species distribution models.
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  • 49
    Publication Date: 2012-05-03
    Description: Modern molecular ecology techniques were used to demonstrate the effects of plant genotype and environmental conditions prior to harvest on the spinach epiphytic bacterial community. Three cultivars of spinach with different leaf topographies were collected at three different periods during the fall growing season. Leaf surface topography had an effect on diversity and number of culturable bacteria on the phylloepiphtyic community of spinach. Savoy cultivars, which had larger surface area and more stomata and glandular trichomes, where bacterial aggregates were observed, featured more diverse communities with increased richness and larger bacterial populations compared to flat-leaved cultivars. Bacterial community richness was compared using denaturant gradient gel electrophoresis (DGGE), while abundance was quantified using 16s rRNA primers for major phyla. The most diverse communities, both in richness and abundance, were observed during the first sampling period, immediately following a period of rapid spinach growth. Exposure to lower air and soil temperatures and decreased precipitation resulted in significantly reduced bacterial population size and bacterial community richness in November and December. This study describes the effect of the plant characteristics and environmental conditions that affect spinach microbiota population size and diversity, which might have implications in the survival of food and plant bacterial pathogens.
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  • 50
    Publication Date: 2012-05-03
    Description: The decline of coral reefs in the Caribbean over the last 40 years has been attributed to multiple chronic stressors and episodic large-scale disturbances. This study assessed the resilience of coral communities in two different regions of the Florida Keys reef system between 1998 and 2002 following hurricane impacts and coral bleaching in 1998. Resilience was assessed from changes in coral abundance, diversity, disease, and bleaching prevalence in reefs near the remote off-shore islands of the Dry Tortugas compared to reefs near Key West, a center of high population density and anthropogenic influences. During the first assessment in spring 1998, Key West and Dry Tortugas coral communities had similar abundance, species diversity, and disease prevalence. Bleaching and disease significantly increased in all reef areas during the summer 1998 El Niño event, with Key West reefs exhibiting higher bleaching and disease prevalence and severity compared to Dry Tortugas. Acroporids and total coral abundance significantly declined in both regions during 1998 following mass-coral bleaching and hurricane impact, but remained reduced only on Key West reefs during the 5-year assessment. These results provide additional evidence that coral reef systems distant from anthropogenic influences may have greater resilience to large-scale disturbances.
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  • 51
    Publication Date: 2012-05-03
    Description: Urban environments pose special challenges to flora, including altered disturbance regimes, habitat fragmentation, and increased opportunity for invasion by non-native species. In addition, urban natural area represents most people’s contact with nature, given the majority of the world’s population currently live in cities. We used coefficients of conservatism (C-values), a system that ranks species based on perceived fidelity to remnant native plant communities that retain ecological integrity, to quantify habitat quality of 14 sites covering 850 ha within the city of Indianapolis, Indiana, in the Midwestern United States. All sites contained significant natural area and were inventoried via intensive complete censuses throughout one or two growing seasons within the last 15 years. Mean C-values for five sites were high, especially when compared to values reported for the highest quality preserves in central Indiana. However, for most sites the difference in mean C-value with and without non-natives was rather high, meaning that natural quality is likely to have been compromised by the presence of non-natives. Sites receiving the highest levels of stewardship and those with the least public access via trails had the highest mean native C-values. A total of 34 invasive non-native species were found across all 14 sites. Most were woody species. Mean C-value over all sites was significantly negatively correlated with the number of non-natives present, especially those considered invasive. These results demonstrate for the Indianapolis area, and likely other urbanized Midwestern cities, remnant natural areas can retain high ecological value, especially if they receive regular environmental stewardship.
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  • 52
    Publication Date: 2012-05-03
    Description: Widespread coral reef decline has included the decline of reef fish populations, and the subsistence and artisanal fisheries that depend on them. Overfishing and destructive fishing have been identified as the greatest local threats to coral reefs, but the greatest future threats are acidification and increases in mass coral bleaching caused by global warming. Some reefs have shifted from dominance by corals to macroalgae, in what are called “phase shifts”. Depletion of herbivores including fishes has been identified as a contributor to such phase shifts, though nutrients are also involved in complex interactions with herbivory and competition. The depletion of herbivorous fishes implies a reduction of the resilience of coral reefs to the looming threat of mass coral mortality from bleaching, since mass coral deaths are likely to be followed by mass macroalgal blooms on the newly exposed dead substrates. Conventional stock assessment of each fish species would be the preferred option for understanding the status of the reef fishes, but this is far too expensive to be practical because of the high diversity of the fishery and poverty where most reefs are located. In addition, stock assessment models and fisheries in general assume density dependent populations, but a key prediction that stocks recover from fishing is not always confirmed. Catch Per Unit Effort (CPUE) has far too many weaknesses to be a useful method. The ratio of catch to stock and the proportion of catch that is mature depend on fish catch data, and are heavily biased toward stocks that are in good condition and incapable of finding species that are in the worst condition. Near-pristine reefs give us a reality check about just how much we have lost. Common fisheries management tools that control effort or catch are often prohibitively difficult to enforce for most coral reefs except in developed countries. Ecosystem-based management requires management of impacts of fishing on the ecosystem, but also vice versa. Marine Protected Areas (MPAs) have been a favorite management tool, since they require little information. MPAs are excellent conservation and precautionary tools, but address only fishing threats, and may be modest fisheries management tools, which are often chosen because they appear to be the only feasible alternative. “Dataless management” is based on qualitative information from traditional ecological knowledge and/or science, is sufficient for successful reef fisheries management, and is very inexpensive and practical, but requires either customary marine tenure or strong governmental leadership. Customary marine tenure has high social acceptance and compliance and may work fairly well for fisheries management and conservation where it is still strong.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 53
    Publication Date: 2012-05-03
    Description: Symbiotic nitrogen fixation is one of the major pathways of N input to forest ecosystems, enriching N availability, particularly in lowland tropics. Recently there is growing concern regarding the wide areas of fast-growing leguminous plantations that could alter global N2O emissions. Here, we highlight substantially different N and phosphorus utilization and cycling at a plantation of Acacia mangium, which is N2-fixing and one of the major plantation species in tropical/subtropical Asia. The litterfall, fresh leaf quality and fine-root ingrowth of A. mangium were compared to those of non-N2-fixing Swietenia macrophylla and coniferous Araucaria cunninghamii in wet tropical climates in Borneo, Malaysia. The N and P concentrations of the A. mangium fresh leaves were higher than those of the other two species, whereas the P concentration in the leaf-litterfall of A. mangium was less than half that of the others; in contrast the N concentration was higher. The N:P ratio in the A. mangium leaf was markedly increased from fresh-leaf (29) to leaf-litterfall (81). Although the N flux in the total litterfall at the A. mangium plantation was large, the fine-root ingrowth of A. mangium significantly increased by applying both N and P. In conclusion, large quantities of N were accumulated and returned to the forest floor in A. mangium plantation, while its P resorption capacity was efficient. Such large N cycling and restricted P cycling in wide areas of monoculture A. mangium plantations may alter N and P cycling and their balance in the organic layer and soil on a stand level.
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  • 54
    Publication Date: 2012-05-03
    Description: To analyze the impact of management choices on diversity in Pyrenean forests, we selected two ecological indicators: springtails; indicators of long-term responses to perturbation, and moths; which respond quickly to changes in their environment. Our data show that monoculture has a short-term impact on overall diversity and richness of species but with a relative resilience capacity of the forest ecosystem. More precisely, real impacts are visible on dynamics and abundances of certain species, depending on the vertical distribution of the biota and on the composition of soil and forest floor.
    Electronic ISSN: 1424-2818
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  • 55
    Publication Date: 2012-05-03
    Description: The ongoing climate warming has been reported to affect a broad range of organisms, and mountain ecosystems are considered to be particularly sensitive because they are limited by low temperatures. Meteorological data show an increased temperature for the alpine areas at Dovrefjell, Norway, causing a prolonged growing season and increased temperature sum. As part of the worldwide project Global Observation Research Initiative in Alpine Environments (GLORIA), the short-term changes in vascular plant species richness, species composition of lichen and vascular plant communities, and abundance of single species were studied at four summits representing an altitudinal gradient from the low alpine to the high alpine zone. During the period from 2001 to 2008, an increase in species richness at the lowest summit, as well as a change in the composition of vascular plant communities, was found at the two lowest summits. The results also indicate an increase in abundance of some shrubs and graminoids and a decline in the cover of some species of lichens at the lowest summit. These changes are in accordance with climate induced changes reported in other studies, but other causes for the observed vegetation changes, in particular changes in grazing and trampling pressure, cannot be ruled out.
    Electronic ISSN: 1424-2818
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  • 56
    Publication Date: 2012-05-03
    Description: Form and function of mycorrhizas as well as tracing the presence of the mycorrhizal fungi through the geological time scale are herein first addressed. Then mycorrhizas and plant fitness, succession, mycorrhizas and ecosystem function, and mycorrhizal resiliency are introduced. From this, four hypotheses are drawn: (1) mycorrhizal diversity evolved in response to changes in Global Climate Change (GCC) environmental drivers, (2) mycorrhizal diversity will be modified by present changes in GCC environmental drivers, (3) mycorrhizal changes in response to ecological drivers of GCC will in turn modify plant, community, and ecosystem responses to the same, and (4) Mycorrhizas will continue to evolve in response to present and future changes in GCC factors. The drivers of climate change examined here are: CO2 enrichment, temperature rise, altered precipitation, increased N-deposition, habitat fragmentation, and biotic invasion increase. These impact the soil-rhizosphere, plant and fungal physiology and/or ecosystem(s) directly and indirectly. Direct effects include changes in resource availability and change in distribution of mycorrhizas. Indirect effects include changes in below ground allocation of C to roots and changes in plant species distribution. GCC ecological drivers have been partitioned into four putative time frames: (1) Immediate (1–2 years) impacts, associated with ecosystem fragmentation and habitat loss realized through loss of plant-hosts and disturbance of the soil; (2) Short-term (3–10 year) impacts, resultant of biotic invasions of exotic mycorrhizal fungi, plants and pests, diseases and other abiotic perturbations; (3) Intermediate-term (11–20 year) impacts, of cumulative and additive effects of increased N (and S) deposition, soil acidification and other pollutants; and (4) Long-term (21–50+ year) impacts, where increased temperatures and CO2 will destabilize global rainfall patterns, soil properties and plant ecosystem resilience. Due to dependence on their host for C-supply, orchid mycorrhizas and all heterotrophic mycorrhizal groups will be immediately impacted through loss of habitat and plant-hosts. Ectomycorrhizal (ECM) associations will be the principal group subject to short-term impacts, along with Ericoid mycorrhizas occurring in high altitude or high latitude ecosystems. This is due to susceptibility (low buffer capacity of soils) of many of the ECM systems and that GCC is accentuated at high latitudes and altitudes. Vulnerable mycorrhizal types subject to intermediate-term GCC changes include highly specialized ECM species associated with forest ecosystems and finally arbuscular mycorrhizas (AM) associated with grassland ecosystems. Although the soils of grasslands are generally well buffered, the soils of arid lands are highly buffered and will resist even fairly long term GCC impacts, and thus these arid, largely AM systems will be the least affect by GCC. Once there are major perturbations to the global hydrological cycle that change rainfall patterns and seasonal distributions, no aspect of the global mycorrhizal diversity will remain unaffected.
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  • 57
    Publication Date: 2012-05-03
    Description: Forty-five Xanthomonas arboricola pv. juglandis (Xaj) strains originating from Juglans regia cultivation in different countries were molecularly typed by means of MultiLocus Sequence Typing (MLST), using acnB, gapA, gyrB and rpoD gene fragments. A total of 2.5 kilobases was used to infer the phylogenetic relationship among the strains and possible recombination events. Haplotype diversity, linkage disequilibrium analysis, selection tests, gene flow estimates and codon adaptation index were also assessed. The dendrograms built by maximum likelihood with concatenated nucleotide and amino acid sequences revealed two major and two minor phylotypes. The same haplotype was found in strains originating from different continents, and different haplotypes were found in strains isolated in the same year from the same location. A recombination breakpoint was detected within the rpoD gene fragment. At the pathovar level, the Xaj populations studied here are clonal and under neutral selection. However, four Xaj strains isolated from walnut fruits with apical necrosis are under diversifying selection, suggesting a possible new adaptation. Gene flow estimates do not support the hypothesis of geographic isolation of the strains, even though the genetic diversity between the strains increases as the geographic distance between them increases. A triplet deletion, causing the absence of valine, was found in the rpoD fragment of all 45 Xaj strains when compared with X. axonopodis pv. citri strain 306. The codon adaptation index was high in all four genes studied, indicating a relevant metabolic activity.
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  • 58
    Publication Date: 2012-05-03
    Description: This article re-examines recent studies that link different forms of social diversity—ethnic polarization and fractionalization—to underdevelopment and an increased risk of civil war. We review theoretical arguments in favor of a connection between diversity and these social outcomes and discuss the inter-linkage between economic growth and internal conflict in situations of extreme diversity. Our analysis confirms that the relationship between ethnic polarization and civil war is ambiguous and depends on the use of civil war incidence or civil war onset as an outcome variable. Furthermore, fractionalization rather than polarization seems to be negatively related to economic growth.
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  • 59
    Publication Date: 2012-05-03
    Description: Telomeres are specialized nucleoprotein structures that have two important functions: (i) protection of the chromosomal ends from deleterious events such as chromosome fusion and degradation; (ii) counteraction of the “end replication problem” by allowing telomerase-dependent or, more rarely, telomerase-independent telomere elongation. The DNA sequences underlying these activities are short simple tandem repeats, which in vertebrate consist of a variable number of TTAGGG. Telomeres dysfunction may be caused either by the absence of telomerase activity or by mutations in telomeric proteins involved in telomere length and structure regulation. Additionally, increasing experimental evidence suggests that telomeres take part in the complex network regulating cell proliferation. Accordingly, telomeres are involved in biological process such as aging and tumor progression. In this study we determined the telomere length in two bovine Italian cattle breeds, Chianina and Maremmana, which are characterized by high longevity and range breeding. In order to account for possible variation among different tissues, we have determined telomere length in different organs such as spleen, lung and liver. Overall, the median telomere length was significant lower in Chianina (11 ± 0.69 kb) than in Maremmana (12.05 ± 1.57 kb). Moreover, telomere length variation among individuals was very low in Chianina but rather high in Maremmana. These data suggest that telomere length is influenced by the breeds. This hypothesis is confirmed by the different history of these Italian breeds. Indeed, Chianina has a long history and its size was maintained by the Breeders Association without necessity to crossbreed with other breeds, whereas the population of Maremmana underwent a dramatic shrinkage in the recent past. Therefore, breeders have crossed Maremmana with other breeds, like Charolais, and have relaxed the rules for the inclusion in the herd book.
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  • 60
    Publication Date: 2012-05-03
    Description: Tropical wetlands are the major natural source of methane released into the atmosphere, producing about 60% of all natural emissions. The great wetland areas of the Amazon basin are the largest source of methane in this region, contributing an estimated 5% of the total emissions from the world’s flooded areas. However, despite the important role that methanogenic archaea play in these environments, there have been few studies on the composition of their archaeal communities. In this survey, four 16S rRNA archaeal clone libraries from different depths were constructed to examine the archaeal community in an Amazon wetland soil. A total of 599 clones were used to perform diversity and phylogenetic analyses. A broad, diverse archaeal community was found at the site, with the diversity decreasing as the depth increased (Shannon index range: 2.40–1.94). Phylogenetic analysis revealed sequences belonging to two archaeal phyla, with 65% classified as Crenarchaeota and 35% classified as Euryarchaeota. Within the Euryarchaeota group, most sequences were clustered into the Methanococci and Methanomicrobia classes, two groups of methanogens. Based on the abundance of methanogenic organisms, culture–dependent isolation was used to isolate these organisms. To enhance the growth of methanogenic archaea, a modified atmosphere (H2:CO2 = 80:20) was established combined with an anoxic environment for 18 months. Among the isolates, the genera Methanosarcina and Methanobacterium were detected throughout the anaerobic in vitro cultivation, indicating a possible role for these organisms in methane production. In conclusion, these exploratory molecular and culture–dependent approaches enhance our understanding of the archaeal community and methanogenic archaea living in wetland soils of the eastern Amazon and their role in methane production.
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  • 61
    Publication Date: 2012-05-03
    Description: We review the application of molecular methods to estimate biodiversity in the marine environment. All of the methods reviewed here, which are at the forefront of molecular research, can be applied to all organisms in all habitats, but the case studies used to illustrate the points are derived from marine photosynthetic eukaryotic protists. It has been accepted that we know less than 10% of the identified diversity in the marine microbial world and the marine micro- and pico-eukaryotes are no exception. Even the species that we think we can easily recognize are often poorly described, and even less is known of their life histories and spatial and temporal trends in their abundance and distribution. With new molecular and analytical techniques, we can advance our knowledge of marine biodiversity at the species level to understand how marine biodiversity supports ecosystem structure, dynamics and resilience. Biogeochemical reactions performed by marine photosynthetic microbial organisms constitute a major sustaining component of ecosystem functioning, and therefore, affect climate changes. New interpretations of how environmental, ecological and evolutionary processes control and structure marine ecosystem biodiversity can be made so that we can augment our understanding of biodiversity and ecosystem dynamics in especially the pico- and nano-fractions of the plankton as well as in the deep sea benthos, both of which are very difficult to study without good analytical methods.
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  • 62
    Publication Date: 2012-05-03
    Description: Molecular-assisted alpha taxonomy has recently become an effective practice in reassessing biodiversity and floristics for a variety of different organisms. This paper presents a series of examples that have been drawn from biodiversity work being carried out on the marine red algae of Bermuda. Molecular sequencing of DNA from Bermuda samples has already begun to greatly alter the makeup of the flora as it was known just decades ago, and will help set a new database for future comparison as climate change affects species composition in the islands.
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  • 63
    Publication Date: 2012-05-03
    Description: Jatropha curcas L. (2n = 2x = 22) is becoming a popular non-food oleaginous crop in several developed countries due to its proposed value in the biopharmaceutical industry. Despite the potentials of its oil-rich seeds as a renewable source of biodiesel and an interest in large-scale cultivation, relatively little is known with respect to plant reproduction strategies and population dynamics. Here, genomic DNA markers and FCSS analyses were performed to gain insights into ploidy variation and heterozygosity levels of multiple accessions, and genomic relationships among commercial varieties of Jatropha grown in different geographical areas. The determination of ploidy and the differentiation of either pseudogamous or autonomous apomixis from sexuality were based on the seed DNA contents of embryo and endosperm. The presence of only a high 2C embryo peak and a smaller 3C endosperm peak (ratio 2:3) is consistent with an obligate sexual reproductive system. Because of the lack of either 4C or 5C endosperm DNA estimates, the occurrence of gametophytic apomixis seems unlikely in this species but adventitious embryony cannot be ruled out. The investigation of genetic variation within and between cultivated populations was carried out using dominant RAPD and Inter-SSR markers, and codominant SSR markers. Nei’s genetic diversity, corresponding to the expected heterozygosity, was equal to He = 0.3491 and the fixation index as low as Fst = 0.2042. The main finding is that seeds commercialized worldwide include a few closely related genotypes, which are not representative of the original Mexican gene pool, revealing high degrees of homozygosity for single varieties and very low genetic diversity between varieties.
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  • 64
    Publication Date: 2012-05-03
    Description: The introduction of livestock species in Europe has been followed by various genetic events, which created a complex spatial pattern of genetic differentiation. Spatial principal component (sPCA) analysis and spatial metric multidimensional scaling (sMDS) incorporate geography in multivariate analysis. This method was applied to three microsatellite data sets for 45 goat breeds, 46 sheep breeds, and 101 cattle breeds from Europe, Southwest Asia, and India. The first two sPCA coordinates for goat and cattle, and the first sPCA coordinate of sheep, correspond to the coordinates of ordinary PCA analysis. However, higher sPCA coordinates suggest, for all three species, additional spatial structuring. The goat is the most geographically structured species, followed by cattle. For all three species, the main genetic cline is from southeast to northwest, but other geographic patterns depend on the species. We propose sPCA and sMDS to be useful tools for describing the correlation of genetic variation with geography.
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  • 65
    Publication Date: 2012-05-03
    Description: In this study, we present the morphological and molecular characterization of the ‘Badda’ bean, a landrace of outstanding organoleptic qualities that is diffused in the area of Polizzi in the province of Palermo in Sicily, Italy. This landrace is entitled to be valorized in the local market and therefore needs a thorough description to draw criteria to establish its distinctiveness from landraces with morphological and geographical proximity. Three ‘Badda’ accessions, representing the morphological variability within the landrace, have been evaluated together with suitable references. With the help of morpho-physiological traits, digital scanning of apical leaflets and ISSR molecular markers, we describe a spectrum of descriptors useful to distinguish the ‘Badda’ accessions among themselves and from similar landraces.
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  • 66
    Publication Date: 2012-05-03
    Description: The chloroplast trnL-F region has been extensively utilized for evolutionary analysis in plants. In the Brassicaceae this fragment contains 1–12 tandemly repeated trnF pseudogene copies in addition to the functional trnF gene. Here we assessed the potential of these highly variable, but complexly evolving duplications, to resolve the population history of the model plant Arabidopsis lyrata. While the region 5’ of the duplications had negligible sequence diversity, extensive variation in pseudogene copy number and nucleotide composition revealed otherwise cryptic population structure in eastern North America. Thus structural changes can be phylogeographically informative when pseudogene evolutionary relationships can be resolved.
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  • 67
    Publication Date: 2012-05-03
    Description: This study evaluated microbial communities of soil (0–10 cm) as affected by dryland cropping systems under different tillage practices after 5 years. The soil type was an Olton sandy loam with an average of 16.4% clay, 67.6% sand and 0.65 g kg−1 of organic matter (OM). The cropping systems evaluated were grain sorghum (Sorghum bicolor L.)—cotton (Gossypium hirsutum) (Srg-Ct), cotton-winter rye (Secale cereale)-grain sorghum (Ct-Rye-Srg), and a rotation of forage (f) sorghum (Sorghum bicolor L. and Sorghum sudanense) with winter rye (Srf-Rye), which were under no-tillage (nt) and conventional tillage (ct) practices. Soil microbial communities under cotton based cropping systems (Srg-Ct and Ct-Rye-Srg) showed lower fungal:bacterial ratios compared to the soil under Srf-Rye. Soil under Srf-Rye showed higher population densities of Bacteroidetes and Proteobacteria while lower Actinobacteria compared to Srg-Ct and Ct-Rye-Srg. Chloroflexi, Gemmatimonadetes and Verrucomicrobiae were higher in tilled soil compared to the no-tilled plots. Regardless the limited irrigation available to sustain agricultural production within these dryland cropping systems, this study demonstrated that differences in microbial communities are more affected by crop rotation than tillage management history. Although soil fungal diversity was not analyzed in this study, pyrosequencing suggests that tillage practices can affect bacterial phyla distribution in this sandy soil.
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  • 68
    Publication Date: 2012-05-03
    Description: Genetic resources of crop plants are essential for crop breeding. They are conserved in gene banks in form of a large numbers of accessions. These accessions harbor allelic variants of agronomically important genes and molecular tools allow a rapid assessment of this allelic diversity. Here, we have screened a collection of 1005 wheat gene bank accessions for powdery mildew resistance and a molecular characterization for functional alleles at the wheat powdery mildew resistance locus Pm3 was carried out mostly on the resistant accessions. The two analyzed sets of accessions consisted of 733 accessions originating from 20 different countries and 272 landraces originating specifically from Afghanistan. The Pm3 haplotype (indicating the presence of a Pm3-type of gene, susceptible or resistant) was found to be abundantly present in both sets. The accessions with a Pm3 haplotype were further screened for the presence of the functional Pm3a to Pm3g alleles using allele-specific molecular markers. Pm3b and Pm3c were the most frequently found alleles while the other five alleles were detected only in few accessions (Pm3d, Pm3e, Pm3f) or not detected at all (Pm3a, Pm3g). The data further showed that Pm3b is the major source of Pm3-mediated powdery mildew resistance in wheat accessions from Afghanistan. Susceptible allelic variants of Pm3 were found to be widespread in the wheat gene pool. The presented molecular analysis of Pm3 alleles in a diverse set of wheat accessions indicates that several alleles have defined geographical origins. Possibly, the widespread Pm3b and Pm3c alleles evolved relatively early in wheat cultivation, allowing their subsequent diffusion into a broad set of wheat lines.
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  • 69
    Publication Date: 2012-05-03
    Description: Honey is produced by honeybees from nectar and from secretions of living plants. It reflects the honeybees’ diet and the local plant communities. Honey also shows different plant compositions in different geographical locations. We propose a new method for studying the plant diversity and the geographical origin of honey using a DNA barcoding approach that combines universal primers and massive parallel pyrosequencing. To test this method we use two commercial honeys, one from a regional origin and one composed of a worldwide mix of different honeys. We demonstrate that the method proposed here is fast, simple to implement, more robust than classical methods, and therefore suitable for analyzing plant diversity in honey.
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  • 70
    Publication Date: 2012-05-03
    Description: There seem to be a certain degree of reluctance in accepting ILP-based methods as part of the range of molecular markers that are classically used for plant genotyping. Indeed, since DNA polymorphism results from difference in length of fragments amplified from specific gene loci, not anonymous sequences, the number of markers that can be generated is sometime inadequate for classical phylogeny studies. Yet, ILP-based markers have many other useful advantages that should not go neglected. We support this statement by presenting a large variety of data we have been collecting for a long while regarding the use of cTBP, an ILP marker based on difference in length of the introns present within the members of the plant beta-tubulin gene family.
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  • 71
    Publication Date: 2012-05-03
    Description: Tobacco (Nicotiana tabacum L.) is an important agricultural crop plant for the economy of many countries. Assessment of the genetic diversity of cultivated tobacco varieties is of importance for long-term tobacco improvement. Microsatellite markers are currently the marker system of choice for genetic analysis of allopolyploid plants. In this study, we evaluated the use of 30 microsatellite markers for identification of 10 varieties of cultivated tobacco in the Republic of Macedonia. We found 24 of the microsatellite markers to be polymorphic and sufficient for identification of these varieties. Cluster analysis showed that Macedonian tobacco varieties are classifiable into three distinct groups.
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  • 72
    Publication Date: 2012-05-03
    Description: Written for anyone interested in green development—including policy makers, architects, developers, builders, and homeowners—this practical guide focuses on the central question of how to conserve biodiversity in neighborhoods and to minimize development impacts on surrounding habitats. The Green Leap specifically helps move green development beyond the design stage by thoroughly addressing construction and post-construction issues. [...]
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  • 73
    Publication Date: 2012-05-03
    Description: Our aim was to investigate species co-occurrence patterns in a large number of published biotic communities, in order to document to what extent species associations can be found in presence-absence matrices. We also aim to compare and evaluate two metrics that focus on species pairs (the ‘natural’ and the ‘checkerboard’ metric) using also artificial matrices. We applied the two metrics to many data sets from a huge variety of insular systems around the world. Both metrics reliably recover deviating species pairs and provide similar, albeit not identical, results. Nevertheless, only a few matrices exhibit significant deviations from random patterns, mostly vertebrates and higher plants. The benchmark cases cited in literature in favor of such assembly rules are indeed included in these exceptional cases. In conclusion, competitive or cooperative species interactions shaping communities cannot be inferred from patterns exhibited by presence-absence matrices. When such an analysis is attempted though, both the ‘natural’ and the ‘checkerboard’ metric should be set in a proper framework in order to provide useful insights regarding species associations. A large part of the discussion on species co-occurrence had originally been based on a few exceptional data sets that are not indicative of general patterns.
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  • 74
    Publication Date: 2012-05-03
    Description: In the original version of our article [1], insufficient acknowledgement was given for the source of some of the DNA samples used. We apologize for the original error. To correct this oversight, Yvonne Willi has been added as an author, a recent paper by Willi, Y. et al. (2010) has been added, the acknowledgements have been altered to more appropriately recognize support and funding, and the sources of samples collected have been corrected in Table 1. [...]
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  • 75
    Publication Date: 2012-05-03
    Description: We summarize the factors that shaped the biodiversity of Chicago and its hinterland and point out the conservation significance of these ecological systems, addressing why conservation of Chicago’s biodiversity has importance locally and beyond. We highlight Chicago Wilderness (CW), a regional biodiversity conservation alliance committed to protecting nature and enriching the lives of the region’s residents. Chicago Wilderness, with over 250 institutional members, has for over a decade coordinated the efforts of diverse institutions, including federal, state, and local agencies, public land-management agencies, conservation organizations, and scientific and cultural institutions. Chicago Wilderness is committed to using science and emerging knowledge as a foundation for its conservation work. CW has several specialist teams that promote an interdisciplinary approach to conservation; we focus on the work of the CW Science Team, the one team with a research mission. The scientific investigations that are undertaken to provide a knowledge base for the work of Chicago Wilderness have drawn upon a wide variety of conservation paradigms, including that of resilience thinking, which we illustrate in a series of case studies.
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  • 76
    Publication Date: 2012-05-03
    Description: Coral reefs are declining worldwide as a result of many anthropogenic disturbances. This trend is alarming because coral reefs are hotspots of marine biodiversity and considered the ‘rainforests of the sea. As in the rainforest, much of the diversity on a coral reef is cryptic, remaining hidden among the cracks and crevices of structural taxa. Although the cryptofauna make up the majority of a reef’s metazoan biodiversity, we know little about their basic ecology or how these communities respond to reef degradation. Emerging research shows that the species richness of the motile cryptofauna is higher among dead (framework) vs. live coral substrates and, surprisingly, increases within successively more eroded reef framework structures, ultimately reaching a maximum in dead coral rubble. Consequently, the paradigm that abundant live coral is the apex of reef diversity needs to be clarified. This provides guarded optimism amidst alarming reports of declines in live coral cover and the impending doom of coral reefs, as motile cryptic biodiversity should persist independent of live coral cover. Granted, the maintenance of this high species richness is contingent on the presence of reef rubble, which will eventually be lost due to physical, chemical, and biological erosion if not replenished by live coral calcification and mortality. The trophic potential of a reef, as inferred from the abundance of cryptic organisms, is highest on live coral. Among dead framework substrates, however, the density of cryptofauna reaches a peak at intermediate levels of degradation. In summary, the response of the motile cryptofauna, and thus a large fraction of the reef’s biodiversity, to reef degradation is more complex and nuanced than currently thought; such that species richness may be less sensitive than overall trophic function.
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  • 77
    Publication Date: 2012-05-03
    Description: Although flawed, the most powerful tool for protecting biodiversity in the United States is the Endangered Species Act, which requires the use of the best available science to ensure that endangered and threatened species are not put in jeopardy of extinction. Unfortunately, the best available science mandate is virtually meaningless and imposes no additional scientific rigor in agency decision making beyond what is normally required of administrative procedures. In this paper, we propose to define best available science in a way that shifts from a way of using science to a way of doing science, and a sound method of doing science for wildlife management and climate change is via the principles of adaptive management [1]. Adaptive management, as a means of data accumulation and continuous learning, can fulfill and give teeth to the best available science mandate while increasing the adaptive capacity of wildlife management agencies to protect biodiversity in an unpredictably dynamic environment.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 78
    Publication Date: 2012-05-03
    Description: The Convention on Biological Diversity has adopted 20 targets as part of its new Strategic Plan. Perrings et al. have proposed that such targets should focus solely on critical ecosystem services. Such a strategy may neglect the need to conserve overall biodiversity and corresponding option values. It also may neglect the important role of ecosystem services in systematic conservation planning strategies that seek effective regional trade-offs and synergies among different needs of society. Parties to the Convention have an opportunity to address not only conventional lists of individual targets for ecosystem services and overall biodiversity, but also higher-level targets that focus directly on how well the country achieves—and maintains its capacity to achieve—effective trade-offs among different needs of society.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 79
    Publication Date: 2012-05-03
    Description: Anticipating the effects of climate change on biodiversity is now critical for managing wild species and ecosystems. Climate change is a global driver and thus affects biodiversity globally. However, land-use planners and natural resource managers need regional or even local predictions. This provides scientists with formidable challenges given the poor documentation of biodiversity and its complex relationships with climate. We are approaching this problem in Quebec, Canada, through the CC-Bio Project (http://cc‑bio.uqar.ca/), using a boundary organization as a catalyst for team work involving climate modelers, biologists, naturalists, and biodiversity managers. In this paper we present the CC-Bio Project and its general approach, some preliminary results, the emerging hypothesis of the northern biodiversity paradox (a potential increase of biodiversity in northern ecosystems due to climate change), and an early assessment of the conservation implications generated by our team work.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 80
    Publication Date: 2012-05-03
    Description: One of the key discussions emerging from within the centre and centre-left of British politics is the means of combining a commitment to diversity with the aim of achieving social solidarity. While there has been a populist strand to this debate recently with the contribution of writers such as Goodhart who has argued that diversity specifically undermines the willingness of the majority (white Anglo-Saxons) to pay for collective welfare provision, there has also been recognition of the difficulty of promoting difference and unity from within even the more sympathetic elements of the academic literature. The purpose of this paper is to consider the nature of this dilemma and to propose a tentative solution. In essence we suggest that the problem lies not in creating a fit between the two elements for the sake of making the ‘new’ social democracy work but in rebuilding traditional social democracy.
    Electronic ISSN: 1424-2818
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  • 81
    Publication Date: 2012-05-03
    Description: Top-down controls of complex foodwebs maintain the balance among the critical groups of corals, algae, and herbivores, thus allowing the persistence of corals reefs as three-dimensional, biogenic structures with high biodiversity, heterogeneity, resistance, resilience and connectivity, and the delivery of essential goods and services to societies. On contemporary reefs world-wide, however, top-down controls have been weakened due to reduction in herbivory levels (overfishing or disease outbreak) while bottom-up controls have increased due to water quality degradation (increase in sediment and nutrient load) and climate forcing (seawater warming and acidification) leading to algal-dominated alternate benthic states of coral reefs, which are indicative of a trajectory towards ecological extinction. Management to reverse common trajectories of degradation for coral reefs necessitates a shift from optimization in marine resource use and conservation towards building socio-economic resilience into coral reef systems while attending to the most manageable human impacts (fishing and water quality) and the global-scale causes (climate change).
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 82
    Publication Date: 2012-05-03
    Description: “Cultural diversity” has become one of the latest buzzwords on the international policymaking scene. It is employed in various contexts—sometimes as a term close to “biological diversity”, at other times as correlated to the “exception culturelle” and most often, as a generic concept that is mobilised to counter the perceived negative effects of economic globalisation. While no one has yet provided a precise definition of what cultural diversity is, what we can observe is the emergence of the notion of cultural diversity as incorporating a distinct set of policy objectives and choices at the global level. These decisions are not confined, as one might have expected, to cultural policymaking, but rather spill over to multiple governance domains because of the complex linkages inherent to the simultaneous pursuit of economic and other societal goals that cultural diversity encompasses and has effects on. Accounting for these intricate interdependencies, the present article clarifies the origins of the concept of cultural diversity as understood in global law and traces its evolution over time. Observing the dynamics of the concept and the surrounding political and legal developments in particular in the context of trade and culture, the article explores its justification and overall impact on the global legal regime, as well as its discrete effects on different domains of policymaking, such as media and intellectual property. While the analysis is legal in essence, the article is also meant to speak to a broader transdisciplinary public.
    Electronic ISSN: 1424-2818
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  • 83
    Publication Date: 2012-05-03
    Description: The processes of land conversion and agricultural intensification are a significant cause of biodiversity loss, with consequent negative effects both on the environment and the sustainability of food production.The anthrosols associated with pre-Colombian settlements in the Amazonian region are examples of how anthropogenic activities may sustain the native populations against harsh tropical environments for human establishment, even without a previous intentionality of anthropic soil formation. In a case study (Model I—“Slash-and-Burn”) the community structures detected by automated ribosomal intergenic spacer analysis (ARISA) revealed that soil archaeal, bacterial and fungal communities are heterogeneous and each capable of responding differently to environmental characteristics. ARISA data evidenced considerable difference in structure existing between microbial communities in forest and agricultural soils. In a second study (Model II—“Anthropogenic Soil”), the bacterial community structures revealed by terminal restriction fragment length polymorphism (T-RFLP) differed among an Amazonian Dark Earth (ADE), black carbon (BC) and its adjacent non-anthropogenic oxisoil. The bacterial 16S rRNA gene (OTU) richness estimated by pyrosequencing was higher in ADE than BC. The most abundant bacterial phyla in ADE soils and BC were Proteobacteria—24% ADE, 15% BC; Acidobacteria—10% ADE, 21% BC; Actinobacteria—7% ADE, 12% BC; Verrucomicrobia, 8% ADE; 9% BC; Firmicutes—3% ADE, 8% BC. Overall, unclassified bacteria corresponded to 36% ADE, and 26% BC. Regardless of current land uses, our data suggest that soil microbial community structures may be strongly influenced by the historical soil management and that anthrosols in Amazonia, of anthropogenic origins, in addition to their capacity of enhancing crop yields, may also improve microbial diversity, with the support of the black carbon, which may sustain a particular and unique habitat for the microbes.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 84
    Publication Date: 2012-05-03
    Description: While bitter manioc has been one of the most important staple crops in the central Amazon for thousands of years, there have been few studies of its cultivation in the fertile whitewater landscapes of this region. Anthropological research on bitter manioc cultivation in the Amazon has focused almost exclusively on long-fallow shifting cultivation in marginal upland areas of low soil fertility. This has contributed to the persistence of the oversimplified notion that because bitter manioc is well adapted to infertile upland soils; it cannot yield well in alluvial and/or fertile soils. I hypothesized that bitter manioc cultivation would be well adapted to the fertile soils of the whitewater landscapes of the central Amazon because of the centrality of this crop to subsistence in this region. In this article, I examine one such whitewater landscape, the middle Madeira River, Amazonas, Brazil, where smallholders cultivate bitter manioc on fertile Amazonian Dark Earths (ADE) and floodplain soils, and on infertile Oxisols and Ultisols. In this region, cultivation on fertile soils tends to be short-cycled, characterised by short fallowing (0–6 years) and shorter cropping periods (5–12 months) with a predominance of low starch fast maturing “weak” landraces. By contrast, cultivation on infertile soils is normally long-cycled, characterised by longer fallows (〉10 years) and longer cropping periods (1–3 years) with a predominance of high starch slow maturing “strong” landraces. This diversity in bitter manioc cultivation systems (landraces, fallow periods, soils) demonstrates that Amazonian farmers have adapted bitter manioc cultivation to the specific characteristics of the landscapes that they inhabit. I conclude that contrary to earlier claims, there are no ecological limitations on growing bitter manioc in fertile soils, and therefore the cultivation of this crop in floodplain and ADE soils would have been possible in the pre-Columbian period.
    Electronic ISSN: 1424-2818
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  • 85
    Publication Date: 2012-05-03
    Description: The emergence of sedentism and agriculture in Amazonia continues to sit uncomfortably within accounts of South American pre-Columbian history. This is partially because deep-seated models were formulated when only ceramic evidence was known, partly because newer data continue to defy simple explanations, and partially because many discussions continue to ignore evidence of pre-Columbian anthropogenic landscape transformations. This paper presents the results of recent geoarchaeological research on Amazonian anthropogenic soils. It advances the argument that properties of two different types of soils, terras pretas and terras mulatas, support their interpretation as correlates of, respectively, past settlement areas and fields where spatially-intensive, organic amendment-reliant cultivation took place. This assessment identifies anthropogenic soil formation as a hallmark of the Amazonian Formative and prompts questions about when similar forms of enrichment first appear in the Amazon basin. The paper reviews evidence for embryonic anthrosol formation to highlight its significance for understanding the domestication of a key Amazonian crop: manioc (Manihot esculenta ssp. esculenta). A model for manioc domestication that incorporates anthropogenic soils outlines some scenarios which link the distribution of its two broader varieties—sweet and bitter manioc—with the widespread appearance of Amazonian anthropogenic dark earths during the first millennium AD.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 86
    Publication Date: 2012-05-03
    Description: The domestic camel (dromedary) is the most important livestock species in the Canary Islands and the most important autochthonous European camel population. After six centuries of a successful adaptation process to the particular environment of the Canary Islands, the abandonment of traditional agriculture has led this population to a major bottleneck. Along with a lack of foreign genetic interchanges, this could lead the population to the brink of extinction. Genetic analysis using 13 microsatellites showed the closest genetic proximity to the North African (Tindouf, Algeria) camel population and a certain degree of sub-division, with significant genetic differences among breeders. An important level of genetic differentiation among the different populations analyzed was found with a global FST value of 0.116.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 87
    Publication Date: 2012-05-03
    Description: Neospora caninum is a parasite regarded a major cause of foetal loss in cattle. A key requirement to an understanding of the epidemiology and pathogenicity of N. caninum is knowledge of the biological characteristics of the species and the genetic diversity within it. Due to the broad intermediate host range of the species, worldwide geographical distribution and its capacity for sexual reproduction, significant biological and genetic differences might be expected to exist. N. caninum has now been isolated from a variety of different host species including dogs and cattle. Although isolates of this parasite show only minor differences in ultrastructure, considerable differences have been reported in pathogenicity using mainly mouse models. At the DNA level, marked levels of polymorphism between isolates were detected in mini- and microsatellites found in the genome of N. caninum. Knowledge of what drives the biological differences that have been observed between the various isolates at the molecular level is crucial in aiding our understanding of the epidemiology of this parasite and, in turn, the development of efficacious strategies, such as live vaccines, for controlling its impact. The purpose of this review is to document and discuss for the first time, the nature of the diversity found within the species Neospora caninum.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 88
    Publication Date: 2012-05-03
    Description: Limited information is available on the bleaching susceptibility of coral species that dominate high latitude reefs along the eastern seaboard of Australia. The main aims of this study were to: (i) monitor coral health and spatial patterns of coral bleaching response at the Solitary Islands Marine Park (SIMP) and Lord Howe Island Marine Park (LHIMP), to determine variability of bleaching susceptibility among coral taxa; (ii) predict coral bleaching thresholds at 30 °S and 31.5 °S, extrapolated from published bleaching threshold data; and (iii) propose a subtropical northern New South Wales coral bleaching model from biological and physical data. Between 2005 and 2007 minor bleaching was observed in dominant coral families including Pocilloporidae, Poritidae and Dendrophylliidae in the SIMP and Pocilloporidae, Poritidae and Acroporidae (Isopora and Montipora spp.) in the LHIMP, with a clear difference in bleaching susceptibility found between sites, both within and between locations. Bleaching susceptibility was highest in Porites spp. at the most offshore island site within the SIMP during summer 2005. Patterns of subtropical family bleaching susceptibility within the SIMP and LHIMP differed to those previously reported for the central Great Barrier Reef (GBR). These differences may be due to a number of factors, including temperature history and/or the coral hosts association with different zooxanthellae clades, which may have lower thermal tolerances. An analysis of published estimates of coral bleaching thresholds from the Caribbean, South Africa, GBR and central and northern Pacific regions suggests that the bleaching threshold at 30–31.5 °S ranges between 26.5–26.8 °C. This predicted threshold was confirmed by an extensive coral bleaching event on the world’s southernmost coral reef at Lord Howe Island, during the 2010 austral summer season. These results imply that dominant coral taxa at subtropical reefs along the eastern Australian seaboard are highly susceptible to thermal stress; which, in turn, could lead to a future decline in total live coral cover if predicted rising seawater temperatures lead to more frequent coral bleaching events in future.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 89
    Publication Date: 2012-05-03
    Description: The remnants of old-growth cedar forests in Lebanon are currently protected since they are taken to represent relic ecosystems sheltering many endemic, rare and endangered species. However, it is not always obvious how “natural” these forest relics are, and how the past use, conservation and management history have affected their current structural properties and species community composition. Even though Integrated Monitoring Programs have been initiated and developed, they are not being implemented effectively. The present research studied the effect of forest stand structure and the impacts of the anthropogenic activities effects on forest composition and floristic richness in four cedar forests in Lebanon. Horizontal and vertical structure was assessed by relying on the measurement of the physical characteristics and status of cedar trees including diversity and similarity indices. Two hundred and seventeen flora species were identified, among which 51 species were found to have biogeographical specificity and peculiar traits. The species composition seems not to be correlated with stand age structure; however, the occurrence of multiple age cedar stands favors floristic richness and variability in species composition as observed in one of the stands where the variation in diversity indices was high. In conclusion; to conserve biodiversity across landscapes, it is necessary to maintain a collection of stands of different vertical structure; an effect produced both by natural and anthropogenic disturbances since they both create a mosaic of different aged succession stands.
    Electronic ISSN: 1424-2818
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  • 90
    Publication Date: 2012-05-03
    Description: Successfully addressing the multitude of stresses influencing forest catchments, their native biota, and the vital ecological services they provide humanity will require adapting an integrated view that incorporates the full range of natural and anthropogenic disturbances acting on these landscapes and their embedded fluvial networks. The concepts of dendritic networks, disturbance domains, the stream continuum, and hydrologic connectivity can facilitate this integration. Managing catchments based on these combined concepts would better maintain all the components of watersheds and the interacting processes that comprise their ecological integrity. To examine these ideas, I review riparian protection regulations in the Pacific Northwest of the United States, regulations considered by many to be among the best available, and evaluate their ability to protect headwater amphibians. I present evidence for the inadequacy of these rules to maintain robust populations of these amphibians, and discuss the implications of these shortcomings for downstream-dwelling coho salmon. Emphasizing headwaters (1st to 3rd-order channels), I discuss disturbance regimes and how differences in their fluvial and geomorphic processes determine the structuring of channels, their internal environments, and the composition of the resident biota. I examine amphibian dependence on specific channel attributes, and discuss links between their abundances, altered attribute states, and natural and anthropogenic disturbances. Using these examples, I discuss the limitations of current protections to maintain key attributes necessary to support robust populations of headwater amphibians, and via hydrologic connectivity, many downstream organisms. I propose that the goal of maintaining whole catchment biodiversity and ecological services could be improved by managing watersheds based on integrating science-based network organizing concepts and evaluating and adjusting outcomes with a suite of responsive bio-indicators.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 91
    Publication Date: 2012-05-03
    Description: The maintenance of genetic diversity is a central goal of conservation. It is the raw material for evolutionary change and if lost, can accelerate extinction of species. According to theory, total genetic diversity should be less in species with restricted ranges and in populations on the margins of distributional ranges, making such species or populations more vulnerable to environmental perturbations. Using mtDNA and nuclear Inter Simple Sequence Repeat (ISSR) data we investigated how the genetic diversity and structure of three con-generic species pairs of coral reef fishes (Pomacentridae) was related to species’ range size and position of populations within these ranges. Estimates of genetic structure did not differ significantly among species, but mtDNA and nucDNA genetic diversities were up to 10 times greater in spatially restricted species compared to their widespread congeners. In two of the three species pairs, the distribution of genetic variation indicated secondary contact among differentiated lineages in the spatially restricted species. In contrast, the widespread species displayed a typical signature of population expansion suggesting recent genetic bottlenecks, possibly associated with the (re) colonization of the Great Barrier Reef. These results indicate that historical processes, involving hybridization and founder effects, possibly associated with Pleistocene sea level fluctuations, have differentially influenced the widespread and spatially restricted coral reef damselfish species studied here.
    Electronic ISSN: 1424-2818
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  • 92
    Publication Date: 2012-05-03
    Description: A recent shift in the pattern of commercial harvest in the Keppel Island region of the southern inshore Great Barrier Reef raises concern about the depletion of a number of relatively rare restricted range taxa. The shift appears to be driven by demand from the United States (US) for corals for domestic aquaria. Data from the annual status reports from the Queensland Coral Fishery were compared with export trade data to the US from the Convention on International Trade in Endangered Species (CITES). Evidence was found of recent increases in the harvest of species from the Mussidae family (Acanthastrea spp.) which appears to be largely driven by demand from the US. On present trends, the industry runs the risk of localized depletion of Blastomussa and Scolymia; evidenced by an increase in the harvest of small specimens and the trend of decreasing harvest despite a concurrent increase in demand. Considering their relatively high sediment tolerance compared to other reef-building species, and the current lack of information about their functional role in reef stability, the trend raises concerns about the impact of the harvest on local coral communities. The recent shift in harvest patterns could have impacts on slow-growing species by allowing harvest beyond the rate of population regeneration. In light of these factors, combined with the value of such species to local tourism, a commercial coral fishery based on uncommon but highly sought-after species may not be ecologically sustainable or economically viable in the Keppels.
    Electronic ISSN: 1424-2818
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  • 93
    Publication Date: 2012-05-03
    Description: In an extensive screening, the antiviral, antitrypanosomal and anticancer properties of extracts from 82 plants used in traditional Chinese medicine and European phytomedicine were determined. Several promising plants that were highly effective against hepatitis B virus (HBV), bovine viral diarrhoea virus (BVDV)—a flavivirus used here as a surrogate in vitro model of hepatitis C virus, trypanosomes (Trypanosoma brucei brucei) and several cancer cell lines were identified. Six aqueous extracts from Celosia cristata, Ophioglossum vulgatum, Houttuynia cordata, Selaginella tamariscina, Alpinia galanga and Alpinia oxyphylla showed significant antiviral effects against BVDV without toxic effects on host embryonic bovine trachea (EBTr) cells, while Evodia lepta, Hedyotis diffusa and Glycyrrhiza spp. demonstrated promising activities against the HBV without toxic effects on host human hepatoblastoma cells transfected with HBV-DNA (HepG2 2.2.15) cells. Seven organic extracts from Alpinia oxyphylla, Coptis chinensis, Kadsura longipedunculata, Arctium lappa, Panax ginseng, Panax notoginseng and Saposhnikovia divaricata inhibited T. b. brucei. Moreover, among fifteen water extracts that combined high antiproliferative activity (IC50 0.5–20 µg/mL) and low acute in vitro toxicity (0–10% reduction in cell viability at IC50), Coptis chinensis presented the best beneficial characteristics. In conclusion, traditional herbal medicine from Europe and China still has a potential for new therapeutic targets and therapeutic applications.
    Electronic ISSN: 1424-2818
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  • 94
    Publication Date: 2012-05-03
    Description: Recently, the Census of Marine Life has explored methods to assess coral reef diversity by combining standardized sampling (to permit comparison across sites) with molecular techniques (to make rapid counts of species possible). To date, this approach has been applied across geographically broad scales (seven sites spanning the Indian, Pacific and Atlantic Oceans), focusing on similar habitats at all sites (10–12 m forereef). Here we examine crustacean spatial diversity patterns for a single atoll, comparing results for four sites (comprising forereef, backreef, and lagoon habitats) at French Frigate Shoals (FFS), Northwestern Hawaiian Islands, Hawaii, USA, within the Papahanaumokuakea Marine National Monument. The Bray-Curtis index of similarity across these habitats at FFS was the same or greater than the similarity between similar habitats on Heron Island and Lizard Island in the Great Barrier Reef and much greater than similarity between more widely separated localities in the Indo-Pacific Ocean (e.g., Ningaloo, Moorea, French Polynesia or the Line Islands). These results imply that, at least for shallow reefs, sampling multiple locations versus sampling multiple habitats within a site maximizes the rate at which we can converge on the best global estimate of coral reef biodiversity.
    Electronic ISSN: 1424-2818
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  • 95
    Publication Date: 2012-05-03
    Description: Knowledge of factors that are important in reef resilience and integrity help us understand how reef ecosystems react following major anthropogenic and environmental disturbances. The North Jamaican fringing reefs have shown some recent resilience to acute disturbances from hurricanes and bleaching, in addition to the recurring chronic stressors of over-fishing and land development. Factors that can improve coral reef resilience are reviewed, and reef rugosity is shown to correlate with coral cover and growth, particularly for branching Acropora species. The biodiversity index for the Jamaican reefs was lowered after the 2005 mass bleaching event, as were the numbers of coral colonies, but both had recovered by 2009. The importance of coastal zone reef management strategies and the economic value of reefs are discussed, and a protocol is suggested for future management of Jamaican reefs.
    Electronic ISSN: 1424-2818
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  • 96
    Publication Date: 2012-05-03
    Description: The long tradition of common bean cultivation in Italy has allowed the evolution of many landraces adapted to restricted areas. Nowadays, in response to market demands, old landraces are gradually being replaced by improved cultivars. However, landraces still survive in marginal areas of several Italian regions. Most of them appear severely endangered with risk of extinction due to the advanced age of the farmers and the socio-cultural context where they are cultivated. The present contribution is an overview of the state of the art about the knowledge of Italian common bean germplasm, describing the most important and recent progresses made in its characterization, including genetic diversity and nutritional aspects.
    Electronic ISSN: 1424-2818
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  • 97
    Publication Date: 2012-05-03
    Description: The starting point is the principle that there is no immigrant culture, but rather, different ways of living, coexisting and identifying oneself within the cultural worlds that each subject crosses on his or her social path. Here we study Brazilian immigrants in Portugal, working with the first wave (starting at the end of the 1980s) and the second wave (at the turn of the 20th to 21st century). We intend, firstly, to show how identity is reconstructed between two banks: the departure culture and the arrival culture. Secondly, we intend to give a voice to the most silent in the understanding of immigrants: the process of identity reconstruction of Brazilian immigrants is presented, resulting from ethno-biographic interviews. We will consider the cultural transfusion theory and observe the heterogeneous ways of living between cultures, whether by rejecting the departure culture (the Oblato‘s case), refusing the arrival one at a given moment (the mono-cultural subject according to the source culture), living in an ambivalent manner between the two (the multicultural self), or, finally, inventing a third bank, as the poets say, which corresponds to an attitude of including the cultural differences through which one crosses during his or her life history in an intercultural self (the Intercultural Transfuga).
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  • 98
    Publication Date: 2012-05-03
    Description: Threatened species often exhibit low genetic diversity as a result of selective sweeps, historical bottlenecks, or persistent small population size. Whereas selective sweeps create localized reduction of variation at a chromosome, population bottlenecks result in the loss of rare alleles throughout the genome. Heterozygosity is lost more slowly and is severely impacted only when populations are small for an extended period of time. We test the hypotheses of selective sweep, historical bottleneck and persistently small population size to explain extremely low genetic diversity in the critically endangered Hawaiian monk seal (Monachus schauinslandi). Of 163 microsatellite loci isolated from the species’ genome, only 17 are polymorphic. Mapping 98 monomorphic and 12 polymorphic loci to 35 chromosomes throughout the dog genome, we reject the selective sweep hypothesis. Genotyping 2,423 Hawaiian monk seals at the 17 polymorphic loci plus a locus previously isolated from another pinniped species, we find evidence for a recent bottleneck (P = 0.04). This is consistent with historical records describing intense hunting in the 19th century; however, the bottleneck was not of sufficient severity and duration to explain the genome-wide depletion of genetic diversity (HO = 0.05; A = 1.1). Long-term population size restriction is a more likely explanation. Though at least two of the polymorphic loci appear to be candidates for selection, the low genetic diversity of the species may further threaten chances for survival of this critically endangered species in a changing world.
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  • 99
    Publication Date: 2012-05-03
    Description: ‘Biodiversity’ means the variety of life and it can be studied at different levels (genetic, species, ecosystem) and scales (spatial and temporal). Last decades showed that marine biodiversity has been severely underestimated at all levels. In order to investigate diversity patterns and underlying processes, there is a need to know what species live in the marine environment. An emerging tool for species identification, DNA barcoding can reliably assign unknown specimens to known species, also flagging potential cryptic species and genetically distant populations. This paper will review the role of DNA barcoding for the study of marine biodiversity at the species level.
    Electronic ISSN: 1424-2818
    Topics: Biology
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  • 100
    Publication Date: 2012-05-03
    Description: In forest ecosystems, fungal mats are functionally important in nutrient and water uptake in litter and wood decomposition processes, in carbon resource allocation, soil weathering and in cycling of soil resources. Fungal mats can occur abundantly in forests and are widely distributed globally. We sampled ponderosa pine/white fir and mountain hemlock/noble fir communities at Crater Lake National Park for mat-forming soil fungi. Fungus collections were identified by DNA sequencing. Thirty-eight mat-forming genotypes were identified; members of the five most common genera (Gautieria, Lepiota, Piloderma, Ramaria, and Rhizopogon) comprised 67% of all collections. The mycorrhizal genera Alpova and Lactarius are newly identified as ectomycorrhizal mat-forming taxa, as are the saprotrophic genera Flavoscypha, Gastropila, Lepiota and Xenasmatella. Twelve typical mat forms are illustrated, representing both ectomycorrhizal and saprotrophic fungi that were found. Abundance of fungal mats was correlated with higher soil carbon to nitrogen ratios, fine woody debris and needle litter mass in both forest ecotypes. Definitions of fungal mats are discussed, along with some of the challenges in defining what comprises a fungal “mat”.
    Electronic ISSN: 1424-2818
    Topics: Biology
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