ALBERT

Description: The general aim of setting up a central database on benthos and plankton was to integrate long-, medium- and short-term datasets on marine biodiversity. Such a database makes it possible to analyse species assemblages and their changes on spatial and temporal scales across Europe. Data collation lasted from early 2007 until August 2008, during which 67 datasets were collected covering three divergent habitats (rocky shores, soft bottoms and the pelagic environment). The database contains a total of 4,525 distinct taxa, 17,117 unique sampling locations and over 45,500 collected samples, representing almost 542,000 distribution records. The database geographically covers the North Sea (221,452 distribution records), the North-East Atlantic (98,796 distribution records) and furthermore the Baltic Sea, the Arctic and the Mediterranean. Data from 1858 to 2008 are presented in the database, with the longest time-series from the Baltic Sea soft bottom benthos. Each delivered dataset was subjected to certain quality control procedures, especially on the level of taxonomy. The standardisation procedure enables pan-European analyses without the hazard of taxonomic artefacts resulting from different determination skills. A case study on rocky shore and pelagic data in different geographical regions shows a general overestimation of biodiversity when making use of data before quality control compared to the same estimations after quality control. These results prove that the contribution of a misspelled name or the use of an obsolete synonym is comparable to the introduction of a rare species, having adverse effects on further diversity calculations. The quality checked data source is now ready to test geographical and temporal hypotheses on a large scale.

Description: Seismic profiles from a venting area on the western margin of Paramushir Island (Sea of Okhotsk) reveal a local complex structure and an interesting, unusual pattern of the bottom simulating reflector (BSR). The BSR is gradual rising towards the venting area. The geothermal gradient and the bottom temperature confirmed the methane hydrate. The temperature appears to be the most important factor controlling the hydrate stability. A locally higher heat flow caused the upward migration of the hydrate stability field and the subsequent degradation of the hydrated sediments, causing gas vent formation and the flux of methane gas into the water column.

Description: Two strains of budding purple bacteria. Rhodobium sp. KR-36m and KR-54m, were isolated from freshwater sulfur-rich hot springs (Kunashire Island, the Kurils) and found to belong to facultative halophiles with a salinity optimum of 1-3%. By most of phenotypic criteria, these bacteria were close to the seawater species Rbi. marinum. They oxidized sulfide to sulfur in the course of photosynthesis, and were in this respect similar to Rbi. marinum: although Rbi. marinum had been described as oxidizing sulfide to sulfur and thiosulfate, the type strain Rbi. marinum DSM 2698 used in this work was found to oxidize sulfide only to sulfur. Based on phenotypic features and data on DNA-DNA homology, strains KR-36m and KR-54m were assigned to the species Rbi. marinum. Accordingly, the diagnosis of this species should be revised as follows: (I) Rbi. marinum oxidizes sulfide to sulfur in the process of photosynthesis, (2) requires thiamine and p-aminobenzoate, (3) and can inhabit freshwater environments, specifically, freshwater sulfur-rich hot springs.

Description: The aim of this study was to determine whether the experimental nutrient enrichment of littoral rocky shore communities would be followed by a predicted accumulation of fast-growing opportunistic algae and a subsequent loss of perennial benthic vegetation. Inorganic nitrogen (N) and potassium (P) was added to eight concrete mesocosms inhabited by established littoral communities dominated by fucoids. The response to nutrient enrichment was followed for almost 2 1/2 years. Fast-growing opportunistic algae (periphyton and ephemeral green algae) grew significantly faster in response to nutrient enrichment, but the growth of red filamentous algae and large perennial brown algae was unaffected. However, these changes were not followed by comparable changes in the biomass and composition of the macroalgae. The biomass of opportunistic algae was stimulated only marginally by the nutrient enrichment, and perennial brown algae (fucoids) remained dominant in the mesocosm regardless of nutrient treatment level. Established rocky shore communities thus seem able to resist the effects of heavy nutrient loading. We found that the combined effects of the heavy competition for space and light imposed by canopy-forming algae, preferential grazing on opportunistic algae by herbivores, and physical disturbance, succeeded by a marked export of detached opportunistic algae, prevented the fast-growing algae from becoming dominant. However, recruitment studies showed that the opportunistic algae would become dominant when free space was available under conditions of high nutrient loading and low grazing pressure. These results show that established communities of perennial algae and associated fauna in rocky shore environments can prevent or delay the accumulation of bloom-forming opportunistic algae and that the replacement of long-lived macroalgae by opportunistic species at high nutrient loading may be a slow process. Nutrient enrichment may not, in itself, be enough to stimulate structural changes in rocky shore communities.

Description: The investigation on the geology of the Sierra Leone Rise contains seismic, petrographic and sedimentological data from the Soviet expedition of R/V »Professor Shtokman«. New results on bottom relief and structure of the Sierra Leone Rise (SLR) are documented in Figs. 1–7. Detailled descriptions of dredge samples of trachyandesites, trachytes, trachyte tuffs, trachybasalts and their tuffs and their chemical composition (Tab. 2) together with the seismic structure of the SLR allow some assumptions on the age and origin of the Rise. The SLR is part of the equatorial Atlantic oceanic crust, that formed in the initial phase of break-up of Gondwana (110–80×106y). During the period 80–90×106 years, when volcanic eruptions were highly intensified in the area, major parts of the SLR have been formed. Some of the volcanic seamounts appeared as islands above sea-level in the Late Cretaceous/Paleocene: the magmatic rocks are more similar to ocean island basalt than to normal oceanic crust. Cenozoic sediments of the SLR reveal continuous sedimentation, which was controlled by surface water productivity, carbonate dissolution and terrigenous matter supply. The Eocene chert sedimentation phase was followed by a period of cyclic carbonate sedimentation. In the Neogene tectonic activity lead to vertical displacements. On several peaked seamounts coral reefs grew. The reef phase was followed by a sinking of the area. At the end of the Neogene the SLR became aseismic. The Late Quaternary sediment cover is studied by means of grab samples and sediment cores from various water depths. The main finding is varying CaCO3 content with depth and with time, controlled mainly by dissolution.

Description: Sharks are a diverse group of mobile predators that forage across varied spatial scales and have the potential to influence food web dynamics. The ecological consequences of recent declines in shark biomass may extend across broader geographic ranges if shark taxa display common behavioural traits. By tracking the original site of photosynthetic fixation of carbon atoms that were ultimately assimilated into muscle tissues of 5,394 sharks from 114 species, we identify globally consistent biogeographic traits in trophic interactions between sharks found in different habitats. We show that populations of shelf-dwelling sharks derive a substantial proportion of their carbon from regional pelagic sources, but contain individuals that forage within additional isotopically diverse local food webs, such as those supported by terrestrial plant sources, benthic production and macrophytes. In contrast, oceanic sharks seem to use carbon derived from between 30° and 50° of latitude. Global-scale compilations of stable isotope data combined with biogeochemical modelling generate hypotheses regarding animal behaviours that can be tested with other methodological approaches.

Description: Populations of fishes provide valuable services for billions of people, but face diverse and interacting threats that jeopardize their sustainability. Human population growth and intensifying resource use for food, water, energy and goods are compromising fish populations through a variety of mechanisms, including overfishing, habitat degradation and declines in water quality. The important challenges raised by these issues have been recognized and have led to considerable advances over past decades in managing and mitigating threats to fishes worldwide. In this review, we identify the major threats faced by fish populations alongside recent advances that are helping to address these issues. There are very significant efforts worldwide directed towards ensuring a sustainable future for the world's fishes and fisheries and those who rely on them. Although considerable challenges remain, by drawing attention to successful mitigation of threats to fish and fisheries we hope to provide the encouragement and direction that will allow these challenges to be overcome in the future.

Description: The present study demonstrates that a distinct land-associated community of mesopelagic micronekton exists around the Hawaiian Islands. This “mesopelagic-boundary community” replaces the oceanic mesopelagic community over bottom depths of approx 400 to 700 m and includes about 14 species of fishes, 5 of shrimps and 4 of squids. Similar species of the mesopelagic micronekton have been reported in association with other landmasses at the boundary between the oceanic mesopelagic realm and upper continental or island slopes. These species may form a cosmopolitan “mesopelagic-boundary community” which shows regional differences in taxonomic composition, abundance and diversity. Boundary communities, with populations which are both tightly constrained geographically and relatively accessible to shore-based research programs, offer unique opportunities for studying biological processes of the mesopelagic realm and the interactions between neritic and oceanic populations. Data is presented from three midwater and two neuston sampling projects undertaken around the main Hawaiian Islands between 1987 and 1989; additional evidence from the literature is also discussed.

Description: Coupling of physical, biological and chemical processes associated with particle resuspension and seston flux was investigated at three sites in the North Sea with contrasting water column (mixed/stratified) and seabed (cohesive/non-cohesive) characteristics.

Description: Background and rationale The coastal zone is the interface through which land-ocean exchanges in the Arctic are mediated and it is the site of most of the human activity that occurs at high latitudes. Arctic coastlines are highly variable and their dynamics are a function of environmental forcing (wind, waves, sea-level changes, sea-ice, etc.), geology, permafrost and its ground-ice content and coastline morphometry. Environmental forcing initiates coastal processes, such as the sediment transport by waves, currents and sea-ice and the degradation of coastal permafrost. The coastal response (erosion or accretion) results in land and habitat loss or gain and thus affects biological and human systems. Figure 1 schematically illustrates the major processes involved in Arctic coastal dynamics. Coastal processes in the Arctic are strongly controlled by Arctic-specific phenomena, i.e. the sea-ice cover and the existence of onshore and offshore permafrost. ... (Excerpt)