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The impurity composition of natural and isotopically enriched silane obtained from magnesium silicide and silicon tetrafluoride is studied by gas chromatography-mass-spectrometry. The impurities characteristic of silane with natural and isotopically enriched composition are atmospheric gases; carbon dioxide; hydrides; saturated, unsaturated, and aromatic hydrocarbons; halogenated hydrocarbons; alkyl derivatives and silane homologues, siloxanes. The impurity content of high-purity silane does not exceed 10.sup.-7-10.sup.-5 mol % After synthesis, the concentrations of impurities in the silane and fractions isolated by its distillation purification lie in the range n x 10.sup.-6 - n x 10 mol % The limits of detection for impurities are 1 x 10.sup.-8-9 x 10.sup.-4 mol %, Author(s): A. Yu. Sozin [sup.1], V. A. Krylov [sup.2], O. Yu. Chernova [sup.1], T. G. Sorochkina [sup.1], A. D. Bulanov [sup.1], O. Yu. Troshin [sup.1], A. P. Kotkov [sup.3], N. [...]

Increased storage of carbon in the oceans has been proposed as a mechanism to explain lower concentrations of atmospheric carbon dioxide during ice ages; however, unequivocal signatures of this storage have not been found.sup.1. In seawater, the dissolved gases oxygen and carbon dioxide are linked via the production and decay of organic material, with reconstructions of low oxygen concentrations in the past indicating an increase in biologically mediated carbon storage. Marine sediment proxy records have suggested that oxygen concentrations in the deep ocean were indeed lower during the last ice age, but that near-surface and intermediate waters of the Pacific Ocean--a large fraction of which are poorly oxygenated at present--were generally better oxygenated during the glacial.sup.1-3. This vertical opposition could suggest a minimal net basin-integrated change in carbon storage. Here we apply a dual-proxy approach, incorporating qualitative upper-water-column and quantitative bottom-water oxygen reconstructions.sup.4,5, to constrain changes in the vertical extent of low-oxygen waters in the eastern tropical Pacific since the last ice age. Our tandem proxy reconstructions provide evidence of a downward expansion of oxygen depletion in the eastern Pacific during the last glacial, with no indication of greater oxygenation in the upper reaches of the water column. We extrapolate our quantitative deep-water oxygen reconstructions to show that the respired carbon reservoir of the glacial Pacific was substantially increased, establishing it as an important component of the coupled mechanism that led to low levels of atmospheric carbon dioxide during the glacial. A downward expansion of oxygen depletion in the eastern Pacific Ocean during the last ice age suggests an increase in the respired carbon reservoir, contributing to the lower levels of atmospheric carbon dioxide during this period., Author(s): Babette A. A. Hoogakker [sup.1] [sup.2] , Zunli Lu [sup.3] [sup.4] , Natalie Umling [sup.5] , Luke Jones [sup.2] , Xiaoli Zhou [sup.6] , Rosalind E. M. Rickaby [sup.2] [...]

The terrestrial biosphere can release or absorb the greenhouse gases, carbon dioxide (C[O.sub.2]), methane (C[H.sub.4]) and nitrous oxide ([N.sub.2]O), and therefore has an important role in regulating atmospheric composition and [...]

No single mechanism can account for the full amplitude of past atmospheric carbon dioxide (C[O.sub.2]) concentration variability over glacial-interglacial cycles (1). A build-up of carbon in the deep ocean has [...]

The latest science news, in brief. The latest science news, in brief., Author Affiliations: Coronavirus nixes conference, twilight zone beckons and a faded star brightens Although thought to be the most abundant vertebrates on Earth, little is known about the species of [...]

The rising atmospheric concentration of carbon dioxide (C[O.sub.2]) should stimulate ecosystem productivity, but to what extent is highly uncertain, particularly when combined with changing temperature and precipitation (1). Ecosystem response to C[O.sub.2] is complicated by biogeochemical feedbacks (2) but must be understood if carbon storage and associated dampening of climate warming are to be predicted (3). Feedbacks through the hydrological cycle are particularly important (4) and the physiology is well known; elevated C[O.sub.2] reduces stomatal conductance and increases plant water use efficiency (the amount of water required to produce a unit of plant dry matter) (5). The C[O.sub.2] response should consequently be strongest when water is limiting (6); although this has been shown in some experiments (7), it is absent from many (8-11). Here we show that large annual variation in the stimulation of aboveground biomass by elevated C[O.sub.2] in a mixed [C.sub.3]/[C.sub.4] temperate grassland can be predicted accurately using seasonal rainfall totals; summer rainfall had a positive effect but autumn and spring rainfall had negative effects on the C[O.sub.2] response. Thus, the elevated C[O.sub.2] effect mainly depended upon the balance between summer and autumn/spring rainfall. This is partly because high rainfall during cool, moist seasons leads to nitrogen limitation, reducing or even preventing biomass stimulation by elevated C[O.sub.2]. Importantly, the prediction held whether plots were warmed by 2°C or left unwarmed, and was similar for [C.sub.3] plants and total biomass, allowing us to make a powerful generalization about ecosystem responses to elevated C[O.sub.2]. This new insight is particularly valuable because climate projections predict large changes in the timing of rainfall, even where annual totals remain static (12). Our findings will help resolve apparent differences in the outcomes of C[O.sub.2] experiments and improve the formulation and interpretation of models that are insensitive to differences in the seasonal effects of rainfall on the C[O.sub.2] response (7,13,14)., Anthropogenic emissions of C[O.sub.2] have been increasing, reaching 9.7billion tonnes of carbon (C) in 2012 (ref. 15). The biosphere absorbs approximately 50% of anthropogenically emitted carbon per annum (16), so [...]

Author(s): Kristie L. Ebi 1,*, Lewis H. Ziska 2 Summary points Higher atmospheric concentrations of carbon dioxide (CO[sub.2] ) increase the growth of cereal crops. At the same time, CO[sub.2] [...]

Author(s): Don A. Cowan; Thulani P. Makhalanyane It might be surprising to some people that the Antarctic continent is not entirely covered by ice. Ice-free areas represent less than 0.4% [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2010.06.016 Byline: Nguyen Phuc Thanh, Yasuhiro Matsui, Takeshi Fujiwara Abstract: This study was undertaken to evaluate the quantity and composition of household solid waste to identify opportunities for waste recycling in Can Tho city, the capital city of the Mekong Delta region in southern Vietnam. Two-stage survey of 100 households was conducted for dry season and rainy season in 2009. Household solid waste was collected from each household and classified into 10 physical categories and 83 subcategories. The average household solid waste generation rate was 285.28g per capita per day. The compostable and recyclable shares respectively accounted for 80.02% and 11.73%. The authors also analyzed the relations between some socioeconomic factors and household solid waste generation rates by physical categories and subcategories. The household solid waste generation rate per capita per day was positively correlated with the population density and urbanization level, although it was negatively correlated with the household size. The authors also developed mathematical models of correlations between the waste generation rates of main physical categories and relevant factors, such as household size and household income. The models were proposed by linear models with three variables to predict household solid waste generation of total waste, food waste, and plastic waste. It was shown that these correlations were weak and a relationship among variables existed. Comparisons of waste generation by physical compositions associated with different factors, such as seasonal and daily variation were conducted. Results presented that the significant average differences were found by the different seasons and by the different days in a week; although these correlations were weak. The greenhouse gas baseline emission was also calculated as 292.25g (CO.sub.2 eq.) per capita per day from biodegradable components. Author Affiliation: Graduate School of Environmental Science, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan Article History: Received 6 April 2010; Revised 12 June 2010; Accepted 16 June 2010

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2010.04.001 Byline: Vamilson PrudA*ncio da Silva (a)(c), Hayo M.G. van der Werf (a)(b), Airton Spies (d), Sebastiao Roberto Soares (c) Abstract: Soybean production and its supply chain are highly dependent on inputs such as land, fertilizer, fuel, machines, pesticides and electricity. The expansion of this crop in Brazil in recent decades has generated concerns about its environmental impacts. To assess these impacts, two representative chains supplying soybeans to Europe were identified: Center West (CW) and Southern (SO) Brazil. Each supply chain was analyzed using Life Cycle Assessment methodology. We considered different levels of use of chemical and organic fertilizers, pesticides and machinery, different distances for transportation of inputs and different yield levels. Because transportation contributed strongly to environmental impacts, a detailed study was performed to identify the routes used to transport soybeans to seaports. Additionally, we considered different levels of land occupation and land transformation to represent the impact of deforestation in the CW region. Environmental impacts were calculated for 1000 kg of soybean up to and including the delivery to Europe at the seaport in Rotterdam, at 13% humidity. Overall results showed that the impacts are greater for CW than for SO for all impact categories studied, including acidification (7.7 and 5.3 kg SO.sub.2 eq., respectively), climate change (959 and 510 kg CO.sub.2 eq.), cumulative energy demand (12,634 and 6,999 MJ) and terrestrial ecotoxicity (4.9 and 3.1 kg 1,4-DCB eq.), except eutrophication and land occupation. The same trend was observed for the crop-production stage. Efforts to reduce chemical fertilizers and diesel consumption can reduce CO.sub.2 emissions. Although deforestation for crop production has decreased in recent years, the contribution of deforestation to climate change and cumulative energy demand remains significant. In the CW scenario deforestation contributed 29% to climate change and 20% to cumulative energy demand. Results also showed that although there are different transportation options in Brazil, the current predominance of road transport causes severe environmental impacts. In CW, road transport contributed 19% to climate change and 24% to cumulative energy demand, while in SO it contributed 12% and 15% to these impacts, respectively. Improvements in the logistics of transportation, giving priority to rail and river transports over road transport, can contribute significantly to reducing greenhouse gas emissions and decreasing energy use. Future studies involving Brazilian soybeans should take into account the region of origin as different levels of environmental impact are predicted. Author Affiliation: (a) INRA, UMR 1069 Sol Agro et hydrosysteme Spatialisation, F-35000 Rennes, France (b) Agrocampus Rennes, UMR 1069 Sol Agro et hydrosysteme Spatialisation, F-35000 Rennes, France (c) Univ. Federal de Santa Catarina, Dep. de Eng. Sanitaria e Ambiental, 88040-970, Florianopolis, Brazil (d) EPAGRI/CEPA, Rod. Admar Gonzaga, 1347, 88034901 Florianopolis, Brazil Article History: Received 11 September 2009; Revised 18 March 2010; Accepted 7 April 2010

Byline: Robert McLeman (1) Keywords: Climate change; Vulnerability; Adaptation; Adaptive capacity; Climate; Migration; Demographic change; Social networks; Ontario; Addington Highlands; Environment Abstract: This article describes and analyzes the impacts of population and demographic change on the vulnerability of communities to climate change and variability. It begins with a review of existing literature on the effects of population change on anthropogenic greenhouse gas emissions, the exposure of settlements to climate risks, and on the capacity to adapt to climate change. The article explores the relationship between population change and adaptive capacity through detailed examination of empirical findings from a study of small communities in eastern Ontario, Canada currently experiencing a combination of changes in local climatic conditions and rapid demographic change caused by in-migration of urban retirees and out-migration of young, educated people. The combination of changing demographic and climatic patterns has placed increased stress on local social networks that have long been critical to climate adaptation in that region. The case study and literature review are used to create a general typology of the relationship between population change and vulnerability that may be used as a framework for future research in this field. Author Affiliation: (1) Department of Geography, University of Ottawa, Room 031 Simard Hall, Ottawa, ON, K1N 6N5, Canada Article History: Registration Date: 18/09/2009 Online Date: 17/12/2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2009.10.010 Byline: Min Zhao (a), Zheng-hong Kong (b), Francisco J. Escobedo (c), Jun Gao (a) Abstract: This study quantified carbon storage and sequestration by urban forests and carbon emissions from energy consumption by several industrial sources in Hangzhou, China. Carbon (C) storage and sequestration were quantified using urban forest inventory data and by applying volume-derived biomass equations and other models relating net primary productivity (NPP) and mean annual biomass increments. Industrial energy use C emissions were estimated by accounting for fossil fuel use and assigning C emission factors. Total C storage by Hangzhou's urban forests was estimated at 11.74Tg C, and C storage per hectare was 30.25t C. Carbon sequestration by urban forests was 1,328, 166.55t C/year, and C sequestration per ha was 1.66t C/ha/year. Carbon emissions from industrial energy use in Hangzhou were 7Tg C/year. Urban forests, through sequestration, annually offset 18.57% of the amount of carbon emitted by industrial enterprises, and store an amount of C equivalent to 1.75 times the amount of annual C emitted by industrial energy uses within the city. Management practices for improving Hangzhou's urban forests function of offsetting C emissions from energy consumption are explored. These results can be used to evaluate the urban forests' role in reducing atmospheric carbon dioxide. Author Affiliation: (a) Urban Ecology and Environment Research Center, Shanghai Normal University, Shanghai 200234, China (b) Key Laboratory of Urbanization and Ecological Restoration, East China Normal University, Shanghai 200062, China (c) School of Forest Resources & Conservation, University of Florida-IFAS, Gainesville, FL 32611, USA Article History: Received 26 March 2009; Revised 27 September 2009; Accepted 23 October 2009

Quantifying atmospheric C[O.sub.2] concentrations ([[C[O.sub.2]].sub.atm]) during Earth's ancient greenhouse episodes is essential for accurately predicting the response of future climate to elevated C[O.sub.2] levels. Empirical estimates of [[C[O.sub.2]].sub.atm] during Paleozoic and Mesozoic greenhouse climates are based primarily on the carbon isotope composition of calcium carbonate in fossil soils. We report that greenhouse [[C[O.sub.2]].sub.atm] have been significantly overestimated because previously assumed soil C[O.sub.2] concentrations during carbonate formation are too high. More accurate [[C[O.sub.2]].sub.atm], resulting from better constraints on soil C[O.sub.2], indicate that large (1,000s of ppmV) fluctuations in [[C[O.sub.2].sub.atm] did not characterize ancient climates and that past greenhouse climates were accompanied by concentrations similar to those projected for A.D. 2100. paleosol barometer | carbon isotopes | pedogenic carbonate | Phanerozoic | climate sensitivity www.pnas.org/cgi/doi/10.1073/pnas.0902323106

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1365-2745.2009.01602.x Byline: Peter H. Wyckoff (*), Rachel Bowers Keywords: climate change; drought; Minnesota; mortality; prairie-forest ecotone; Quercus macrocarpa; tree-rings Abstract: Summary 1.Quercus macrocarpa (bur oak) is the dominant tree species along much of the prairie-forest border in the northern-central United States, and movement of Q. macrocarpa in response to climate change may determine the rate at which the prairie-forest ecotone shifts. To investigate likely controls over Q. macrocarpa performance at the edge of its range, we used tree rings to establish the links between drought, growth-rate and mortality for three sites spanning the prairie-forest border in Minnesota. 2.Quercus macrocarpa growth during the 20th century correlates strongly with the Palmer Drought Severity Index (PDSI) and more weakly with raw temperature and precipitation values for all three sites. However, the sensitivity of annual growth rates to drought has steadily declined over time as evidenced by increasing growth residuals and higher growth rates for a given PDSI value after 1950 compared with the first half of the century. We hypothesize that increased atmospheric carbon dioxide concentration may lead to increased water-use efficiency, although we cannot rule out other environmental factors. 3. Because growth is an excellent predictor of Q. macrocarpa mortality, growth-climate relationships provide information on whether oak forests will contract, because of individual tree death, when climate changes. For Q. macrocarpa, declining sensitivity of growth to drought translates into lower predicted mortality rates at all sites. At one site, declining moisture sensitivity yields a 49% lower predicted mortality from a severe drought (PDSI = -8, on par with the worst 1930s 'American Dust Bowl' droughts in our study region). 4. Unless the changing relationship between growth and climate is incorporated into forest simulation models, the predicted rate of established tree dieback in a warmer, drier climate may be exaggerated. 5.Synthesis. Adult Quercus macrocarpa trees appear to be increasingly insensitive to drought-induced mortality. Because the species is dominant at the prairie-forest ecotone in the northern-central United States, movement of the ecotone in response to climate change may be delayed for decades. Article History: Received: 17 June 2009; accepted 9 October 2009 Handling Editor: Matthew Turnbull Article note: (*) Correspondence author. E-mail: wyckoffp@morris.umn.edu

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2009.09.013 Byline: David Rivest (a), Alain Cogliastro (b), Alain Olivier (a) Abstract: Tree-based intercropping is considered to be a potentially useful land use system for mitigating negative environmental impacts from intensive agriculture such as nutrient leaching and greenhouse gas emissions. Rapid early growth of trees is critical for rapidly accruing environmental benefits provided by the trees. We tested the hypothesis that intercropping increases the growth and nutrient status of young hybrid poplars (Populus spp.), compared to a harrowing alley treatment (i.e., no intercrop), in two experimental sites (St-Remi and St-Edouard) in southern Quebec, Canada. Three hybrid poplar clones (TD3230, Populus trichocarpa x deltoides; DN3308, P. deltoides x nigra; and NM3729, P. nigra x maximowiczii) were planted at St-Remi. Clones DN3333 and DN3570 were planted at St-Edouard. At St-Remi, intercropping comprised a 4-year succession of three crops of soybean (Glycine max (L.) Merr.) and barley (Hordeum vulgare L.). At St-Edouard, intercropping comprised a 3-year succession of buckwheat (Fagopyrum esculentum Moench), winter rye (Secale cereale L.), and winter wheat (Triticum aestivum L.). At St-Remi, four years after treatment began, leafless aboveground biomass of hybrid poplars in the intercropping treatment was 37% higher compared to that in the harrowing treatment. At St-Edouard, after the third growing season, leafless aboveground biomass of hybrid poplars in the intercropping treatment was significantly higher by 40%. Vector analysis of foliar nutrient concentrations and comparison with critical concentration values showed that N (both sites) and K (St-Edouard) were the most limiting nutrients. Hybrid poplar clones responded similarly to treatments, with no consistent differences in tree growth observed between clones. We conclude that tree-based intercropping systems may offer an effective means of improving the early growth of hybrid poplars planted to provide both environmental services and high-value timber. Author Affiliation: (a) Departement de phytologie, Universite Laval, Quebec (QC), Canada G1K 7P4 (b) Institut de recherche en biologie vegetale, Universite de Montreal & Jardin botanique de Montreal, 4101 est rue Sherbrooke, Montreal (QC), Canada H1X 2B2 Article History: Received 23 February 2009; Revised 10 August 2009; Accepted 1 September 2009

A new field of study, 'decadal prediction,' is emerging in climate science. Decadal prediction lies between seasonal/interannual forecasting and longer-term climate change projections, and focuses on time-evolving regional climate conditions over the next 10-30 yr. Numerous assessments of climate information user needs have identified this time scale as being important to infrastructure planners, water resource managers, and many others. It is central to the information portfolio required to adapt effectively to and through climatic changes. At least three factors influence time-evolving regional climate at the decadal time scale: 1) climate change commitment (further warming as the coupled climate system comes into adjustment with increases of greenhouse gases that have already occurred), 2) external forcing, particularly from future increases of greenhouse gases and recovery of the ozone hole, and 3) internally generated variability. Some decadal prediction skill has been demonstrated to arise from the first two of these factors, and there is evidence that initialized coupled climate models can capture mechanisms of internally generated decadal climate variations, thus increasing predictive skill globally and particularly regionally. Several methods have been proposed for initializing global coupled climate models for decadal predictions, all of which involve global time-evolving three-dimensional ocean data, including temperature and salinity. An experimental framework to address decadal predictability/prediction is described in this paper and has been incorporated into the coot dinated Coupled Model Intercomparison Model, phase 5 (CMIP5) experiments, some of which will be assessed for the IPCC Fifth Assessment Report (AR5). These experiments will likely guide work in this emerging field over the next 5 yr. DOI: 10.1175/2009BAMS2778.1

During the North American monsoon (NAM) season (July-September), the most severe thunderstorms that cause life-threatening flash floods in the North American Southwest are due to surges of very moist air [...]

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1365-2745.2009.01547.x Keywords: carbon; climate change; DGVM; feedbacks; GCM; models; PFT; plant; soil Abstract: Summary 1. Plant-soil interactions play a central role in the biogeochemical carbon (C), nitrogen (N) and hydrological cycles. In the context of global environmental change, they are important both in modulating the impact of climate change and in regulating the feedback of greenhouse gas emissions (CO.sub.2, CH.sub.4 and [N.sub.2]O) to the climate system. 2. Dynamic global vegetation models (DGVMs) represent the most advanced tools available to predict the impacts of global change on terrestrial ecosystem functions and to examine their feedbacks to climate change. The accurate representation of plant-soil interactions in these models is crucial to improving predictions of the effects of climate change on a global scale. 3. In this paper, we describe the general structure of DGVMs that use plant functional types (PFTs) classifications as a means to integrate plant-soil interactions and illustrate how models have been developed to improve the simulation of: (a) soil carbon dynamics, (b) nitrogen cycling, (c) drought impacts and (d) vegetation dynamics. For each of these, we discuss some recent advances and identify knowledge gaps. 4. We identify three ongoing challenges, requiring collaboration between the global modelling community and process ecologists. First, the need for a critical evaluation of the representation of plant-soil processes in global models; second, the need to supply and integrate knowledge into global models; third, the testing of global model simulations against large-scale multifactor experiments and data from observatory gradients. 5. Synthesis. This paper reviews how plant-soil interactions are represented in DGVMs that use PFTs and illustrates some model developments. We also identify areas of ecological understanding and experimentation needed to reduce uncertainty in future carbon coupled climate change predictions. Author Affiliation: (1)Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP, UK (2)Institute of Biological and Environmental Sciences, University of Aberdeen, St Machar Drive, Aberdeen AB24 3UU, UK (3)Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK (4) Environmental Change Institute, School of Geography & the Environment, University of Oxford, Oxford OX1 3QY, UK (5)Centre for Ecology and Hydrology, Bush Estate, Penicuik, Midlothian, Edinburgh EH26 0QB, UK (6)School of Geosciences, Edinburgh University, Drummond Street, Edinburgh EH8 9XP, UK (7)Soil and Ecosystem Ecology Group, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK Article History: Received 10 March 2009; accepted 22 June 2009 Handling Editor: Hans Cornelissen Article note: (*) Correspondence author. E-mail: no@ceh.ac.uk

Atmospheric carbon dioxide (C[O.sub.2]) is increasing at an accelerating rate, primarily due to fossil fuel combustion and land use change. A substantial fraction of anthropogenic C[O.sub.2] emissions is absorbed by the oceans, resulting in a reduction of seawater pH. Continued acidification may over time have profound effects on marine biota and biogeochemical cycles. Although the physical and chemical basis for ocean acidification is well understood, there exist few field data of sufficient duration, resolution, and accuracy to document the acidification rate and to elucidate the factors governing its variability. Here we report the results of nearly 20 years of time-series measurements of seawater pH and associated parameters at Station ALOHA in the central North Pacific Ocean near Hawaii. We document a significant long-term decreasing trend of -0.0019 [+ or -] 0.0002 [y.sup.-1] in surface pH, which is indistinguishable from the rate of acidification expected from equilibration with the atmosphere. Superimposed upon this trend is a strong seasonal pH cycle driven by temperature, mixing, and net photosynthetic C[O.sub.2] assimilation. We also observe substantial interannual variability in surface pH, influenced by climate-induced fluctuations in upper ocean stability. Below the mixed layer, we find that the change in acidification is enhanced within distinct subsurface strata. These zones are influenced by remote water mass formation and intrusion, biological carbon remineralization, or both. We suggest that physical and biogeochemical processes alter the acidification rate with depth and time and must therefore be given due consideration when designing and interpreting ocean pH monitoring efforts and predictive models. carbon cycle | climate change | C[O.sub.2] | pH | Station ALOHA

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2009.04.012 Byline: A. Papageorgiou (a), J.R. Barton (b), A. Karagiannidis (a) Abbreviations: AEA, AEA Technology; AiIE, Associates in Industrial Ecology; APC, air pollution control; CHP, combined heat and power; CH.sub.4, methane; CO.sub.2, carbon dioxide; CO.sub.2-eq, carbon dioxide equivalents; DEFRA, Department for Environment Food and Rural Affairs; DOC, degradable organic carbon; DOC.sub.F, fraction DOC dissimilated; DTI, Department of Trade and Industry; EC, European Commission; EF, emission factor; EfW, energy from waste; ERM, Environmental Resources Management; FBI, fluidised bed incinerator; GCV, gross calorific value; GHG, greenhouse gas; GWP, global warming potential; HFCs, hydrofluorocarbons; IPCC, Intergovernmental panel on climate change; L.sub.0, methane generation potential; MBI, Mass Burn Incineration; MBT, mechanical biological treatment; MCF, methane correction factor; MHT, mechanical heat treatment; MSW, municipal solid waste; NCV, net calorific value; N.sub.2O, nitrous oxide; PFCs, perfluorocarbons; OX, oxidation factor; SNCR, selective non-catalytic reduction; SRF, solid recovered fuel; SF.sub.6, sulphur hexafluoride Abstract: Waste management activities contribute to global greenhouse gas emissions approximately by 4%. In particular the disposal of waste in landfills generates methane that has high global warming potential. Effective mitigation of greenhouse gas emissions is important and could provide environmental benefits and sustainable development, as well as reduce adverse impacts on public health. The European and UK waste policy force sustainable waste management and especially diversion from landfill, through reduction, reuse, recycling and composting, and recovery of value from waste. Energy from waste is a waste management option that could provide diversion from landfill and at the same time save a significant amount of greenhouse gas emissions, since it recovers energy from waste which usually replaces an equivalent amount of energy generated from fossil fuels. Energy from waste is a wide definition and includes technologies such as incineration of waste with energy recovery, or combustion of waste-derived fuels for energy production or advanced thermal treatment of waste with technologies such as gasification and pyrolysis, with energy recovery. The present study assessed the greenhouse gas emission impacts of three technologies that could be used for the treatment of Municipal Solid Waste in order to recover energy from it. These technologies are Mass Burn Incineration with energy recovery, Mechanical Biological Treatment via bio-drying and Mechanical Heat Treatment, which is a relatively new and uninvestigated method, compared to the other two. Mechanical Biological Treatment and Mechanical Heat Treatment can turn Municipal Solid Waste into Solid Recovered Fuel that could be combusted for energy production or replace other fuels in various industrial processes. The analysis showed that performance of these two technologies depends strongly on the final use of the produced fuel and they could produce GHG emissions savings only when there is end market for the fuel. On the other hand Mass Burn Incineration generates greenhouse gas emission savings when it recovers electricity and heat. Moreover the study found that the expected increase on the amount of Municipal Solid Waste treated for energy recovery in England by 2020 could save greenhouse gas emission, if certain Energy from Waste technologies would be applied, under certain conditions. Author Affiliation: (a) Laboratory of Heat Transfer and Environmental Engineering, Department of Mechanical Engineering, Box 483, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece (b) School of Civil Engineering, Faculty of Engineering, The University of Leeds, LS2 9JT Leeds, UK Article History: Received 7 August 2008; Revised 27 February 2009; Accepted 2 April 2009

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1600-0706.2009.17220.x Abstract: Growing empirical evidence suggests that aboveground and belowground multitrophic communities interact. However, investigations that comprehensively explore the impacts of above- and belowground third and higher trophic level organisms on plant and herbivore performance are thus far lacking. We tested the hypotheses that above- and belowground higher trophic level organisms as well as decomposers affect plant and herbivore performance and that these effects cross the soil-surface boundary. We used a well-validated simulation model that is individual-based for aboveground trophic levels such as shoot herbivores, parasitoids, and hyperparasitoids while considering belowground herbivores and their antagonists at the population level. We simulated greenhouse experiments by removing trophic levels and decomposers from the simulations in a factorial design. Decomposers and above- and belowground third trophic levels affected plant and herbivore mortality, root biomass, and to a lesser extent shoot biomass. We also tested the effect of gradual modifications of the interactions between different trophic level organisms with a sensitivity analysis. Shoot and root biomass were highly sensitive to the impact of the fourth trophic level. We found effects that cross the soil surface, such as aboveground herbivores and parasitoids affecting root biomass and belowground herbivores influencing aboveground herbivore mortality. We conclude that higher trophic level organisms and decomposers can strongly influence plant and herbivore performance. We propose that our modelling framework can be used in future applications to quantitatively explore the possible outcomes of complex above- and belowground multitrophic interactions under a range of environmental conditions and species compositions. Article History: Manuscript Accepted 16 March 2009 Article note: K. M. Meyer (kmeyer5@uni-goettingen.de), L. E. M. Vet and W. H. van der Putten, Netherlands Inst. of Ecology NIOO-KNAW, Centre for Terrestrial Ecology, Dept of Multitrophic Interactions, Boterhoeksestraat 48, NL-6666 GA Heteren, the Netherlands. Present address for KMM: Faculty of Forest Sciences and Ecology, Ecosystem Modelling, Univ. of Gottingen, Busgenweg 4, DE-37077 Gottingen, Germany. - M. Vos, Netherlands Inst. of Ecology NIOO-KNAW, Centre for Estuarine and Marine Ecology, Dept of Ecosystem Studies, Korringaweg 7, NL-4401 NT Yerseke, the Netherlands. Present address: Dept of Ecology and Ecosystem Modeling, Inst. of Biochemistry and Biology, Univ. of Potsdam, Am Neuen Palais 10, DE-14469 Potsdam, Germany. - W. M. Mooij, Netherlands Inst. of Ecology NIOO-KNAW, Centre for Limnology, Dept of Food Web Studies, Rijkstraatweg 6, NL-3631 AC Nieuwersluis, the Netherlands. - W. H. Gera Hol, Netherlands Inst. of Ecology NIOO-KNAW, Centre for Terrestrial Ecology, Dept of Terrestrial Microbial Ecology, Boterhoeksestraat 48, NL-6666 GA Heteren, the Netherlands. - A. J. Termorshuizen, Blgg, Nieuwe Kanaal 7f, NL-6709 PA Wageningen, the Netherlands.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2009.02.004 Byline: Ines Ahumada (a), Orianne Gudenschwager (a), M. Adriana Carrasco (b), Gabriela Castillo (c), Loreto Ascar (a), Pablo Richter (a) Abstract: The purpose of this study was assessing Cu and Zn availabilities in soils amended with a biosolid through the determination of their sequentially extracted chemical forms and their relationship with the contents of these metals in ryegrass (Lolium perenne L.) and subterranean clover (Trifolium subterraneum L.) plant tissues cultivated in a greenhouse using four soils classified as Aquic Xerochrepts and Ultic Haploxeralfs representatives of potential areas for biosolids application in the central zone of Chile. The soils were treated with sewage sludge at a rate of 0 and 30Mgha.sup.-1. The greenhouse experiment was carried out through a completely randomized block design in a 2x4 (biosolid ratexsoil) arrangement, considering three repetitions per treatment. The soils used in the greenhouse experiment before and after cultivation, were sequentially extracted with specific reagents and conditions in order to obtain the following fractions: exchangeable, sodium acetate-soluble, soluble in moderately reducing condition, K.sub.4P.sub.2O.sub.7-soluble, soluble in reducing condition, and soluble in strongly acid and oxidizing condition. It was established that Cu and Zn were predominantly found in soils in less available forms, associated to organic matter, oxides and clay minerals. Zinc concentration in ryegrass plants was higher than that found in subterranean clover plants in biosolid-amended soils. Zinc contents in ryegrass shoot and root correlated with the exchangeable, bound-to-carbonate, and bound-to-FeOx metal forms in control soil. Copper and Zn bioavailabilities were estimated through satisfactorily fitted multiple linear regression models, with determination coefficients from 0.77 to 0.99, which showed a positive contribution of the labile metal forms in soils, especially in relation to Zn in both plant species. Author Affiliation: (a) Facultad de Cs. Quimicas y Farmaceuticas. Universidad de Chile, casilla 233, Santiago, Chile (b) Facultad de Cs. Agronomicas. Universidad de Chile, Casilla 1004, Santiago, Chile (c) Facultad de Cs. Fisicas y Matematicas. Universidad de Chile, Casilla 2777, Santiago, Chile Article History: Received 29 January 2008; Revised 26 January 2009; Accepted 8 February 2009

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1523-1739.2008.01096.x Keywords: biofuel plantation; compensation point; oil-palm plantation biodiversity; oil-palm plantation emission; palm-oil production impact; peatland conversion; plantation development Abstract: Abstract: The growing demand for biofuels is promoting the expansion of a number of agricultural commodities, including oil palm (Elaeis guineensis). Oil-palm plantations cover over 13 million ha, primarily in Southeast Asia, where they have directly or indirectly replaced tropical rainforest. We explored the impact of the spread of oil-palm plantations on greenhouse gas emission and biodiversity. We assessed changes in carbon stocks with changing land use and compared this with the amount of fossil-fuel carbon emission avoided through its replacement by biofuel carbon. We estimated it would take between 75 and 93 years for the carbon emissions saved through use of biofuel to compensate for the carbon lost through forest conversion, depending on how the forest was cleared. If the original habitat was peatland, carbon balance would take more than 600 years. Conversely, planting oil palms on degraded grassland would lead to a net removal of carbon within 10 years. These estimates have associated uncertainty, but their magnitude and relative proportions seem credible. We carried out a meta-analysis of published faunal studies that compared forest with oil palm. We found that plantations supported species-poor communities containing few forest species. Because no published data on flora were available, we present results from our sampling of plants in oil palm and forest plots in Indonesia. Although the species richness of pteridophytes was higher in plantations, they held few forest species. Trees, lianas, epiphytic orchids, and indigenous palms were wholly absent from oil-palm plantations. The majority of individual plants and animals in oil-palm plantations belonged to a small number of generalist species of low conservation concern. As countries strive to meet obligations to reduce carbon emissions under one international agreement (Kyoto Protocol), they may not only fail to meet their obligations under another (Convention on Biological Diversity) but may actually hasten global climate change. Reducing deforestation is likely to represent a more effective climate-change mitigation strategy than converting forest for biofuel production, and it may help nations meet their international commitments to reduce biodiversity loss. Abstract (Spanish): Plantaciones de Biocombustible en Terrenos Boscosos: Doble Peligro para la Biodiversidad y el Clima Resumen: La creciente demanda de biocombustibles esta promoviendo la expansion de activos agricolas, incluyendo la palma de aceite (Elaeis guineensis). Las plantaciones de palma de aceite cubren mas de 13 millones de ha, principalmente en el sureste de Asia, donde han reemplazado a bosques tropicales directa o indirectamente. Exploramos el impacto de la expansion de las plantaciones de palma de aceite sobre la emision de gases de invernadero y la biodiversidad. Evaluamos los cambios en las reservas de carbono con el cambio de uso de suelo y comparamos esto con la cantidad de emisiones de carbono de combustibles fosiles que se evitarian con su reemplazo por carbono de biocombustibles. Estimamos que pasarian entre 75 y 93 anos para que las emisiones de carbono ahorradas por el uso de biocombustible compensen el carbono perdido por la conversion de bosques, dependiendo de como fue removido el bosque. Si el habitat original era turbera, el balance de carbono tardaria mas de 600 anos, Por el contrario, sembrando las plantaciones de palma en pastizales degradados llevaria a una remocion de carbono en 10 anos. Estas estimaciones estan asociadas con incertidumbre, pero su magnitud y proporciones relativas parecen creibles. Realizamos un meta analisis de los estudios de fauna publicados que comparan bosques con palma de aceite. Encontramos que las plantaciones soportan comunidades de baja riqueza con pocas especies de bosque. Debido a que no se dispuso de datos de flora publicados, presentamos los resultados de nuestro muestreo de plantas en parcelas de palma de aceite y de bosque en Indonesia. Aunque la riqueza de especies de pteridofitas fue mayor en las plantaciones, contenian pocas especies de bosque. Arboles, lianas, orquideas epifitas y palmas nativas estuvieron totalmente ausentes de las plantaciones de palma de aceite. La mayoria de plantas y animales individuales en las plantaciones de palma de aceite pertenecian a un pequeno numero de especies generalistas de bajo interes para la conservacion. A medida que los paises pugnan por cumplir las obligaciones de reduccion de emisiones de carbono en el marco de un acuerdo internacional (Protocolo de Kioto), no solo pueden fallar en cumplir sus obligaciones en el marco de otro (Convencion de Diversidad Biologica) sino que incluso pueden acelerar el cambio climatico. La reduccion de la deforestacion probablemente represente una estrategia mas efectiva para la mitigacion del cambio climatico que la conversion de bosques para la produccion de biocombustibles, y puede ayudar a que las naciones cumplan sus compromisos internacionales para la reduccion de la perdida de biodiversidad. Author Affiliation: (*)NORDECO, Skindergade 23-III, Copenhagen DK-1159, Denmark, emailfd@nordeco.dk ([dagger])University of Groningen, P. O. Box 14, 9750 AA Haren, Netherlands ([double dagger])Conservation Science Group, Department of Zoology, University of Cambridge, Cambridge, United Kingdom (s.)World Wildlife Fund USA, 1250 24th Street NW, Washington, D.C. 20090-7180, U.S.A. (**)Global Environment Centre, 2nd Floor, Wisma Hing, 78, Jalan SS2/72, Petaling Jaya, Selangor, Malaysia ([dagger][dagger])Institute for Environmental Sciences, University Koblenz-Landau, Fortstra[sz]e 7, D-76829 Landau, Germany ([double dagger][double dagger])RSPB, The Lodge, Sandy, Bedfordshire, United Kingdom (s.s.)CIFOR, P.O. BOX 6596, JKPWB, Jakarta, Indonesia (***)IBED, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, Netherlands ([dagger][dagger][dagger])Queen Mary University of London, London, United Kingdom ([double dagger][double dagger][double dagger])Institute of Zoology, Zoological Society of London, Regent's Park, London, United Kingdom (s.s.s.)School of Environmental Services, University of East Anglia, Norwich, United Kingdom Article History: Paper submitted February 4, 2008; revised manuscript accepted August 20, 2008.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2007.12.011 Byline: Gregory J. McKee (a), Rachael E. Goodhue (b), Frank G. Zalom (c), Colin A. Carter (b), James A. Chalfant (b) Abstract: In agriculture, relatively few efficacious control measures may be available for an invasive pest. In the case of a new insect pest, insecticide use decisions are affected by regulations associated with its registration, insect population dynamics, and seasonal market price cycles. We assess the costs and benefits of environmental regulations designed to regulate insecticide applications on an invasive species. We construct a bioeconomic model, based on detailed scientific data, of management decisions for a specific invasion: greenhouse whiteflies in California-grown strawberries. The empirical model integrates whitefly population dynamics, the effect of whitefly feeding on strawberry yields, and weekly strawberry price. We use the model to assess the optimality of alternative treatment programs on a simulated greenhouse whitefly population. Our results show that regulations may lead growers to 'under-spray' when placed in an economic context, and provide some general lessons about the design of optimal invasive species control policies. Author Affiliation: (a) Department of Agribusiness and Applied Economics, North Dakota State University, 205 A Morrill Hall, Fargo, ND 58102, USA (b) Department of Agricultural and Resource Economics, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA (c) Department of Entomology, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA Article History: Received 27 April 2007; Revised 15 November 2007; Accepted 8 December 2007

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2007.10.011 Byline: H.W. Lu (a), G.H. Huang (a)(b), L. He (a), G.M. Zeng (c) Abstract: Municipal solid waste (MSW) should be properly disposed in order to help protect environmental quality and human health, as well as to preserve natural resources. During MSW disposal processes, a large amount of greenhouse gas (GHG) is emitted, leading to a significant impact on climate change. In this study, an inexact dynamic optimization model (IDOM) is developed for MSW-management systems under uncertainty. It grounds upon conventional mixed-integer linear programming (MILP) approaches, and integrates GHG components into the modeling framework. Compared with the existing models, IDOM can not only deal with the complex tradeoff between system cost minimization and GHG-emission mitigation, but also provide optimal allocation strategies under various emission-control standards. A case study is then provided for demonstrating applicability of the developed model. The results indicate that desired waste-flow patterns with a minimized system cost and GHG-emission amount can be obtained. Of more importance, the IDOM solution is associated with over 5.5 million tonnes of TEC reduction, which is of significant economic implication for real implementations. Therefore, the proposed model could be regarded as a useful tool for realizing comprehensive MSW management with regard to mitigating climate-change impacts. Author Affiliation: (a) Faculty of Engineering, University of Regina, Regina, SK S4S 0A2, Canada (b) Chinese Research Academy of Environmental Science, North China Electric Power University, Beijing 100012-102206, China (c) College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China Article History: Received 18 October 2006; Revised 30 September 2007; Accepted 30 October 2007

An electrostatic discharge test was carried out on a solar array paddle (SAP) for the Greenhouse gases Observing SATellite (GOSAT) on a simulated polar Earth orbit (PEO) environment. To simulate the spacecraft charging conditions in a PEO with an auroral band, when electrons with higher energy than LEO plasma flow to the Earth, three conditions of dielectric charging can be considered on each side of the SAP. At first, the threshold voltage differences of discharge inception were measured experimentally using solar array coupons simulating both the beginning and the end of life under six charging conditions. Next, the Multiutility Spacecraft Charging Analysis Tool was employed to analyze the spacecraft surface potential and the time needed for charging. From the threshold value and the charging analysis, the probability and the number of discharges were estimated in each charging condition during a lifetime of the GOSAT. Finally, the performance of the coupons against discharges was evaluated for each charging condition. All coupons had no sustained arc during these tests; however, there was some electrical degradation of the solar cell. The power degradation during the lifetime of the GOSAT was estimated from these results, and the design of the solar array coupon was confirmed to satisfy the power demand even if the estimated number of discharges occurs in the lifetime. Index Terms--Electrostatic discharge (ESD) test, polar Earth orbit (PEO), solar array, spacecraft charging.

Global climate models predict that the strongest dependences of surface air temperatures on increasing atmospheric carbon dioxide levels will occur in the Arctic. A systematic study of these dependences requires accurate Arctic-wide measurements, especially of cloud coverage. Thus cloud detection in the Arctic is extremely important, but it is also challenging because of the similar remote sensing characteristics of clouds and ice-and snow-covered surfaces. This article proposes two new operational Arctic cloud detection algorithms using Multiangle Imaging Spector Radiometer (MISR) imagery. The key idea is to identify cloud-free surface pixels in the imagery instead of cloudy pixels as in the existing MISR operational algorithms. Through extensive exploratory data analysis and using domain knowledge, three physically useful features to differentiate surface pixels from cloudy pixels have been identified. The first algorithm, enhanced linear correlation matching (ELCM), thresholds the features with either fixed or data-adaptive cutoff values. Probability labels are obtained by using ELCM labels as training data for Fisher's quadratic discriminant analysis (QDA), leading to the second (ELCM-QDA) algorithm. Both algorithms are automated and computationally efficient for operational processing of the massive MISR data set. Based on 5 million expert-labeled pixels, ELCM results are significantly in terms of both accuracy (92%) and coverage (100%) compared with two MISR operational algorithms, one with an accuracy of 80% and coverage of 27% and the other with an accuracy of 83% and a coverage of 70%. The ELCM-QDA probability prediction is also consistent with the expert labels and is more informative. In conclusion, ELCM and ELCM-QDA provide the best performance to date among all available operational algorithms using MISR data. KEY WORDS: Classification; Clustering; Feature selection; Multiangle imaging spectroradiometer; Quadratic discriminate analysis; Remote sensing.

A stomatal frequency record based on buried Tsuga heterophylla needles reveals significant centennial-scale atmospheric C[O.sub.2] fluctuations during the last millennium. The record includes four C[O.sub.2] minima of 260-275 ppmv (ca. A.D. 860 and A.D. 1150, and less prominently, ca. A.D. 1600 and 1800). Alternating C[O.sub.2] maxima of 300-320 ppmv are present at A.D. 1000, A.D. 1300, and ca. A.D. 1700. These C[O.sub.2] fluctuations parallel global terrestrial air temperature changes, as well as oceanic surface temperature fluctuations in the North Atlantic. The results obtained in this study corroborate the notion of a continuous coupling of the preindustrial atmospheric C[O.sub.2] regime and climate. Keywords: carbon dioxide, paleoclimatc, Holocene, conifers, climate controls, paleoecology.

Air bubbles which were trapped in polar ice have been analysed and the concentrations of CO2 over various periods have been calculated. Changes in the climate over many thousands of years tend to change the concentrations of CO2 in the atmosphere. However, CO2 concentrations during rapid climate changes are less certain. Research into CO2 from Greenland and Antarctic ice has been inconclusive. An accurate time scale is required to compare the data from Greenland with the Antarctic and a method has been developed which uses concentrations of atmospheric methane from both the ice samples.

A systems approach is necessary to fully assess the impacts of land clearance and crop production on atmospheric carbon dioxide (CO2). Based on long-term carbon changes and fossil fuel energy inputs, it is evident that increased crop productivity will lessen the amount of atmospheric CO2. However, future self-containment of the energy requirements of high-yield crop production may displace on the order of 1.0 Pg C per year of fossil fuel carbon. The avoidance of land cultivation also allows high-yield crop systems to preserve natural ecosystems.

At a time when all continents were finally arrayed in their Pangea supercontinental configuration (250 [+ or -] 50 Ma), Earth's stratigraphy records a global and very abrupt coal discontinuity. From the Tartarian stage of the Late Permian to the Middle Triassic, reduced coal productivity and/or preservation overlaps with a period of anomalous oceanic and atmospheric decrease in 13C, as recorded in marine carbonates and organic matter, and terrestrial plant and animal fossils from the Northern and Southern hemispheres. During the same short period, the peripheral margin of the entire supercontinent Pangea, except for the southern shores of Tethys, was effectively under compressive stress. This unique tectonic state caused deformation and uplift of coal-bearing foreland basins and oxidation of Pangea's vast peat deposits. The latter resulted in a rapid, massive 13C-depleted C[O.sup.2] flux into the atmosphere, which in turn may have forced global warming.

An experimental study of the response of an intact native ecosystem to increased CO2 reveals that native ecosystems do not always show positive responses to increased CO2 and that these responses might often be complicated. A CO2 level doubling reinstates total homeostasis of the CO2 flux while CO2 doubling and exposure of ecosystems to high temperatures result in a continuous fertilization impact on total carbon sequestration. The difference is due to increased sink activity due to high temperature effects on growth and to increased nutrient supply due to elevated mineralization.

Studies on palaesol carbon isotope ratios show the shift from C4-influenced grasses to C3-influenced shrubs 7 to 9 thousand years ago. The shift occurred in the alluvial fauna system in the Chihuahuan desert, NM. The shift created rapid increase in the atmospheric carbon-dioxide concentration. The increased acidity in the ice cores of the Antarctic is recorded by these geomorphic reconstructions and palaeosol oxygen isotope investigations.

Author(s): K. M. Walter Anthony (corresponding author) [1]; S. A. Zimov [2]; G. Grosse [3, 10]; M. C. Jones [1, 4]; P. M. Anthony [1]; F. S. Chapin III [5]; [...]

Simulations of the flux of atmospheric carbon dioxide into the ocean show that changes in flux associated with human activities are currently masked by natural climate variations, but will be [...]

Carbon dioxide emission scenarios do not influence the global warming potential of CO2 with respect to other radioactive trace gases. Six scenarios are examined to indicate that atmospheric CO2 concentration is inversely proportional to the variation in climate. The sea absorbs less CO2 from the atmosphere due to increased concentrations of dissolved carbon in the sea's surface.