ALBERT

Description: We examine the little-known phenomenon of orbitally modulated Si i emission at 3905.523 Å and 4102.936 Å in composite-spectrum binaries, with specific reference to Aurigae (K4 Ib + B5 V). The emission is detected in the isolated spectrum of the B-type dwarf secondary, and while 4102 Å is heavily blended with H, 3905 Å falls in the B-star's featureless continuum. The narrowness of the emission ( v turb ~= 6 km s –1 ) demonstrates that it originates in the upper photosphere or deep chromosphere of the K star primary. We propose that photoexcitation by the hot star's UV continuum, followed by recombination and cascades, leads to resonant scattering and subsequent pumping of lower opacity transitions in the singlet and triplet systems of Si i . This process channels the UV continuum into select narrow emission lines. We have also identified weaker photoexcited emission of Fe ii at 3938.289 Å. The strengths, positions, and widths of the 3905 Å emission line vary with orbital phase owing to changes in the dilution of the irradiating flux and in the geometrical aspect of the irradiated hemisphere. Utilizing the inherent spatial resolution provided by the illuminated patch, and assuming that the K star is spherical with isotropic emission, yields v sin i ~ 5.7 km s –1 . Evidence of tidal distortion was deduced from the timing of the rapidly rising phase of the emission just after periastron. Increasing the diagnostic potential requires radiative transfer modelling of the formation and centre-to-limb variation of the emission.

Description: Managing multiple ecosystem services (ES), including addressing trade-offs between services and preventing ecological surprises, is among the most pressing areas for sustainability research. These challenges require ES research to go beyond the currently common approach of snapshot studies limited to one or two services at a single point in time....

Description: Increasing population and consumption are placing unprecedented demands on agriculture and natural resources. Today, approximately a billion people are chronically malnourished while our agricultural systems are concurrently degrading land, water, biodiversity and climate on a global scale. To meet the world's future food security and sustainability needs, food production must grow substantially while, at the same time, agriculture's environmental footprint must shrink dramatically. Here we analyse solutions to this dilemma, showing that tremendous progress could be made by halting agricultural expansion, closing 'yield gaps' on underperforming lands, increasing cropping efficiency, shifting diets and reducing waste. Together, these strategies could double food production while greatly reducing the environmental impacts of agriculture.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Foley, Jonathan A -- Ramankutty, Navin -- Brauman, Kate A -- Cassidy, Emily S -- Gerber, James S -- Johnston, Matt -- Mueller, Nathaniel D -- O'Connell, Christine -- Ray, Deepak K -- West, Paul C -- Balzer, Christian -- Bennett, Elena M -- Carpenter, Stephen R -- Hill, Jason -- Monfreda, Chad -- Polasky, Stephen -- Rockstrom, Johan -- Sheehan, John -- Siebert, Stefan -- Tilman, David -- Zaks, David P M -- England -- Nature. 2011 Oct 12;478(7369):337-42. doi: 10.1038/nature10452.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institute on the Environment (IonE), University of Minnesota, 1954 Buford Avenue, Saint Paul, Minnesota 55108, USA. jfoley@umn.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21993620" target="_blank"〉PubMed〈/a〉

Description: The planetary boundaries framework defines a safe operating space for humanity based on the intrinsic biophysical processes that regulate the stability of the Earth system. Here, we revise and update the planetary boundary framework, with a focus on the underpinning biophysical science, based on targeted input from expert research communities and on more general scientific advances over the past 5 years. Several of the boundaries now have a two-tier approach, reflecting the importance of cross-scale interactions and the regional-level heterogeneity of the processes that underpin the boundaries. Two core boundaries-climate change and biosphere integrity-have been identified, each of which has the potential on its own to drive the Earth system into a new state should they be substantially and persistently transgressed.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Steffen, Will -- Richardson, Katherine -- Rockstrom, Johan -- Cornell, Sarah E -- Fetzer, Ingo -- Bennett, Elena M -- Biggs, Reinette -- Carpenter, Stephen R -- de Vries, Wim -- de Wit, Cynthia A -- Folke, Carl -- Gerten, Dieter -- Heinke, Jens -- Mace, Georgina M -- Persson, Linn M -- Ramanathan, Veerabhadran -- Reyers, Belinda -- Sorlin, Sverker -- New York, N.Y. -- Science. 2015 Feb 13;347(6223):1259855. doi: 10.1126/science.1259855. Epub 2015 Jan 15.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Stockholm Resilience Centre, Stockholm University, 10691 Stockholm, Sweden. Fenner School of Environment and Society, The Australian National University, Canberra, ACT 2601, Australia. will.steffen@anu.edu.au. ; Center for Macroecology, Evolution, and Climate, University of Copenhagen, Natural History Museum of Denmark, Universitetsparken 15, Building 3, 2100 Copenhagen, Denmark. ; Stockholm Resilience Centre, Stockholm University, 10691 Stockholm, Sweden. ; Department of Natural Resource Sciences and McGill School of Environment, McGill University, 21, 111 Lakeshore Road, Ste-Anne-de-Bellevue, QC H9X 3V9, Canada. ; Stockholm Resilience Centre, Stockholm University, 10691 Stockholm, Sweden. Centre for Studies in Complexity, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa. ; Center for Limnology, University of Wisconsin, 680 North Park Street, Madison WI 53706 USA. ; Alterra Wageningen University and Research Centre, P.O. Box 47, 6700AA Wageningen, Netherlands. Environmental Systems Analysis Group, Wageningen University, P.O. Box 47, 6700 AA Wageningen, Netherlands. ; Department of Environmental Science and Analytical Chemistry, Stockholm University, 10691 Stockholm, Sweden. ; Stockholm Resilience Centre, Stockholm University, 10691 Stockholm, Sweden. Beijer Institute of Ecological Economics, Royal Swedish Academy of Sciences, SE-10405 Stockholm, Sweden. ; Research Domain Earth System Analysis, Potsdam Institute for Climate Impact Research (PIK), Telegraphenberg A62, 14473 Potsdam, Germany. ; Research Domain Earth System Analysis, Potsdam Institute for Climate Impact Research (PIK), Telegraphenberg A62, 14473 Potsdam, Germany. International Livestock Research Institute, P.O. Box 30709, Nairobi, 00100 Kenya. CSIRO (Commonwealth Scientific and Industrial Research Organization), St. Lucia, QLD 4067, Australia. ; Centre for Biodiversity and Environment Research (CBER), Department of Genetics, Evolution and Environment, University College London, Gower Street, London WC1E 6BT, UK. ; Stockholm Environment Institute, Linnegatan 87D, SE-10451 Stockholm, Sweden. ; Scripps Institution of Oceanography, University of California at San Diego, 8622 Kennel Way, La Jolla, CA 92037 USA. TERI (The Energy and Resources Institute) University, 10 Institutional Area, Vasant Kunj, New Delhi, Delhi 110070, India. ; Stockholm Resilience Centre, Stockholm University, 10691 Stockholm, Sweden. Natural Resources and the Environment, CSIR, P.O. Box 320, Stellenbosch 7599, South Africa. ; Division of History of Science, Technology and Environment, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25592418" target="_blank"〉PubMed〈/a〉

Description: Decline in agricultural biodiversity (cultivated species and wild species used for food or that support agro-ecosystem functioning) at the farm scale has fueled concerns about potential negative effects of this biodiversity loss on the ecological and economic sustainability of agro-ecosystems. Despite these concerns, formal assessment of how agro-biodiversity has historically changed at scales larger than individual farms is fragmented. We quantified the changes in the abundance of 10 crop and livestock species, their overall diversity, and the way they were mixed in ‘baskets’ of agricultural products from 1911 to 2006, at a sub-regional (15 Regional County Municipalities) and regional scales. We found that the diversity of agricultural products increased at the regional scale. From 1911 to 1966, the region produced fodder, milk and maple, mixed in two low-diversity baskets. After 1966, the region provided a greater variety of baskets composed of newly introduced cash crops and ...

Description: Understanding how landscape structure, the composition and configuration of land use/land cover (LULC) types, affects the relative supply of ecosystem services (ES), is critical to improving landscape management. While there is a long history of studies on landscape composition, the importance of landscape configuration has only recently become apparent. To understand the role of landscape structure in the provision of multiple ES, we must understand how ES respond to different measures of both composition and configuration of LULC. We used a multivariate framework to quantify the role of landscape configuration and composition in the provision of ten ES in 130 municipalities in an agricultural region in Southern Québec. We identified the relative influence of composition and configuration in the provision of these ES using multiple regression, and on bundles of ES using canonical redundancy analysis. We found that both configuration and composition play a role in explaining var...

Description: 〈p〉Soil organisms, including earthworms, are a key component of terrestrial ecosystems. However, little is known about their diversity, their distribution, and the threats affecting them. We compiled a global dataset of sampled earthworm communities from 6928 sites in 57 countries as a basis for predicting patterns in earthworm diversity, abundance, and biomass. We found that local species richness and abundance typically peaked at higher latitudes, displaying patterns opposite to those observed in aboveground organisms. However, high species dissimilarity across tropical locations may cause diversity across the entirety of the tropics to be higher than elsewhere. Climate variables were found to be more important in shaping earthworm communities than soil properties or habitat cover. These findings suggest that climate change may have serious implications for earthworm communities and for the functions they provide.〈/p〉

Description: 〈p〉The magnitude and pace of global change demand rapid assessment of nature and its contributions to people. We present a fine-scale global modeling of current status and future scenarios for several contributions: water quality regulation, coastal risk reduction, and crop pollination. We find that where people’s needs for nature are now greatest, nature’s ability to meet those needs is declining. Up to 5 billion people face higher water pollution and insufficient pollination for nutrition under future scenarios of land use and climate change, particularly in Africa and South Asia. Hundreds of millions of people face heightened coastal risk across Africa, Eurasia, and the Americas. Continued loss of nature poses severe threats, yet these can be reduced 3- to 10-fold under a sustainable development scenario.〈/p〉