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The International Journal of Life Cycle Assessment - The EU environmental footprint (EF) is a life cycle assessment (LCA)-based method which aims at assessing the environmental impacts of... 相似文献
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根据生态足迹方法,建立了种植业生态足迹模型,计算了2001—2006年沈阳地区种植业生态足迹,分析了单位重量农产品生态足迹构成变化规律及其原因。结果表明:2001—2006年,沈阳地区种植业生态足迹呈现先下降后上升趋势,单位重量农产品生态足迹总体呈下降趋势;耕地足迹是沈阳种植业生态足迹的主要成分,水足迹次之,能源足迹所占比重最小。2001—2006年间,耕地足迹从56.8%降到54.4%;水足迹在27.6%~32.1%波动;而能源足迹从14.0%增加到16.2%;农产品单产的提高伴随着钾肥、复合肥、农药、农膜、农用钢材和柴油投入量的增加。表明近年来沈阳地区种植业生产对化石能源的依赖程度在加大。 相似文献
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In August 1998, Texas A&M University implemented on campus a trap-test-vaccinate-alter-return-monitor (TTVARM) program to manage the feral cat population. TTVARM is an internationally recognized term for trapping and neutering programs aimed at management of feral cat populations. In this article we summarize results of the program for the period August 1998 to July 2000. In surgery laboratories, senior veterinary students examined cats that were humanely trapped once a month and tested them for feline leukemia and feline immunodeficiency virus infections, vaccinated, and surgically neutered them. They euthanized cats testing positive for either infectious disease. Volunteers provided food and observed the cats that were returned to their capture sites on campus and maintained in managed colonies. The program placed kittens and tame cats for adoption; cats totaled 158. Of the majority of 158 captured cats, there were less kittens caught in Year 2 than in Year 1. The proportion of tame cats trapped was significantly greater in Year 2 than in Year 1. The prevalence found for feline leukemia and feline immunodeficiency virus ELISA test positives was 5.8% and 6.5%, respectively. Following surgery, 101 cats returned to campus. The project recaptured, retested, and revaccinated more than one-fourth of the cats due for their annual vaccinations. The program placed 32 kittens, juveniles, and tame adults for adoption. The number of cat complaints received by the university's pest control service decreased from Year 1 to Year 2. 相似文献
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Purpose A complete assessment of water use in life cycle assessment (LCA) involves modelling both consumptive and degradative water use. Due to the range of environmental mechanisms involved, the results are typically reported as a profile of impact category indicator results. However, there is also demand for a single score stand-alone water footprint, analogous to the carbon footprint. To facilitate single score reporting, the critical dilution volume approach has been used to express a degradative emission in terms of a theoretical water volume, sometimes referred to as grey water. This approach has not received widespread acceptance and a new approach is proposed which takes advantage of the complex fate and effects models normally employed in LCA. Methods Results for both consumptive and degradative water use are expressed in the reference unit H 2Oe, enabling summation and reporting as a single stand-alone value. Consumptive water use is assessed taking into consideration the local water stress relative to the global average water stress (0.602). Concerning degradative water use, each emission is modelled separately using the ReCiPe impact assessment methodology, with results subsequently normalised, weighted and converted to the reference unit (H 2Oe) by comparison to the global average value for consumptive water use (1.86?×?10 ?3 ReCiPe points m ?3). Results and discussion The new method, illustrated in a simplified case study, incorporates best practice in terms of life cycle impact assessment modelling for eutrophication, human and eco-toxicity, and is able to assimilate new developments relating to these and any other impact assessment models relevant to water pollution. Conclusions The new method enables a more comprehensive and robust assessment of degradative water use in a single score stand-alone water footprint than has been possible in the past. 相似文献
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电力碳足迹旨在测度发电过程中所引起的生命周期CO2排放水平.本研究从地球碳循环的角度入手,在综合大量研究数据的基础上,针对不同电力来源的碳排放特征,结合地表覆被的碳吸收能力,分类测算了全球平均电力碳足迹当量(即单位电力消费量所产生的生命周期碳足迹),并实证分析了2000-2008年全球电力碳足迹的构成及变化.结果表明:煤炭类火电(以下简称煤电)、石油类火电、天然气类火电、水电和核电的全球平均碳足迹当量分别为131.3×10-6、95.8×10-6、56.6×10-6、38.8×10-6、1.9×10-6 hm2·(kW·h)-1,火电特别是煤电的环境影响显著大于水电和核电;2000-2008年,全球电力碳足迹由730.7×106 hm2增至1101.8×106 hm2,其中火电占比由60.0%增至68.1%,煤炭取代石油成为火电碳足迹的主要构成部分,而水电和核电占比则分别降至30.7%、1.3%;全球电力结构总体趋于劣化,平均碳排放系数由265.8×10-3kg·(kW· h)-1增至315.4×10-3 kg·(kW·h)-1,火电特别是煤电在很大程度上决定着电力碳排放的强度与规模. 相似文献
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Ecological footprint analysis (EFA) has been used since the early 1990s as a measure of sustainability for geographical regions, products, and activities. EFA is used as a measure of land and water ecosystems needed to provide the resources for a given population and process the waste that it produces in a globalized metric (global hectares), generally on an annual basis. As institutions seek ways to become more sustainable they have used a variety of metrics, ranking systems, and indicators to evaluate their baseline and progress towards those goals. An EFA for a large urban public university, the University of Illinois at Chicago (UIC), was calculated as 97,601 global hectares (2.66 global hectares per total faculty, staff and students). The breakdown of sources is energy for the built environment (73%), transportation and commuting (13%), materials and waste (12%), and food (3%). UIC's ecological footprint to actual landprint ratio has a value of 1005 which is 1–2 orders of magnitude higher than the other campuses that have performed EFAs. This is an indicator of the urban nature of the campus since the land resources in an urban environment are limited and the activities tend to be denser. A sensitivity analysis to examine the effect of climate change events on the footprint indicated that, if all other factors are held constant, climate change will increase the ecological footprint of UIC. 相似文献
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Floristic inventory of wild plants comprised of total 129 plant species belonging to 42 families and 101 genera. Location wise UAP contributed greater amount of plant species (53%), followed by PFI (29%), UoP (15%) and Islamia College (3%). Majority of the plants were annual herbs (58%), followed by perennial herbs (29%), trees (10%) and shrubs (3%), respectively. The leading families included Poaceae, contributed 18% of all the plant species. Habitat wise, 44% of them grew in grassy plains, abandoned lands and mismanaged lawns, followed by roadsides (34%), undulating grassy plains (15%) and stony grounds with uneven topography along with stream banks and drainage ditches (7%). Still some of plant species were used as ornamentals, while some shrubs were use in fencing around fields; others were utilized as green manure, for fishing, sheltering and religious purposes. Exploring and identifying the wild flora of the campus and compiling as a handbook would help to monitor new plants introductions particularly of noxious invasive weeds in the campuses in future. 相似文献
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截至2010年12月,为期2年的河南大学校园鸟类调查共记录到鸟类44种,隶属11目、25科;其中雀形目鸟类28种,留鸟20种,夏候鸟18种,冬候鸟和旅鸟各3种,分别占总数的63.6%、45.5%、40.9%、6.8%和6.8%;区系分析表明东洋种9种,古北种16种,广布种19种,分别占总数的20.5%、36.4%和43.2%。整体表现出南北混杂,古北种鸟类较东洋种比例大,广布种鸟类较多的特点。在调查基础上,提出了一些校园鸟类保护的建议。 相似文献
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Using estimates of the primary production required (PPR) to support fisheries catches (a measure of the footprint of fishing), we analyzed the geographical expansion of the global marine fisheries from 1950 to 2005. We used multiple threshold levels of PPR as percentage of local primary production to define 'fisheries exploitation' and applied them to the global dataset of spatially-explicit marine fisheries catches. This approach enabled us to assign exploitation status across a 0.5° latitude/longitude ocean grid system and trace the change in their status over the 56-year time period. This result highlights the global scale expansion in marine fisheries, from the coastal waters off North Atlantic and West Pacific to the waters in the Southern Hemisphere and into the high seas. The southward expansion of fisheries occurred at a rate of almost one degree latitude per year, with the greatest period of expansion occurring in the 1980s and early 1990s. By the mid 1990s, a third of the world's ocean, and two-thirds of continental shelves, were exploited at a level where PPR of fisheries exceed 10% of PP, leaving only unproductive waters of high seas, and relatively inaccessible waters in the Arctic and Antarctic as the last remaining 'frontiers.' The growth in marine fisheries catches for more than half a century was only made possible through exploitation of new fishing grounds. Their rapidly diminishing number indicates a global limit to growth and highlights the urgent need for a transition to sustainable fishing through reduction of PPR. 相似文献
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2008年3~7月采用样线法对长江师范学院李渡校园鸟类组成和种群数量进行了调查,共记录鸟类6目21科28种,数量1633只,物种多样性指数为3.9204,均匀性指数为1.1765,其中国家“三有”名录鸟类25种,CITES名录鸟类1种。鸟类区系以东洋界成分为主。对不同生境鸟类多样性的分析结果表明:(1)乔灌林鸟类多样性指数和均匀性指数最高,水域鸟类多样性指数最低,建筑区均匀性指数最低;(2)乔灌林与竹林的相似性指数最高,竹林与水域的相似性最低。 相似文献
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Background Recently a new class of methods for fast protein structure comparison has emerged. We call the methods in this class projection methods as they rely on a mapping of protein structure into a high-dimensional vector space. Once the mapping is done, the structure comparison is reduced to distance computation between corresponding vectors. As structural similarity is approximated by distance between projections, the success of any projection method depends on how well its mapping function is able to capture the salient features of protein structure. There is no agreement on what constitutes a good projection technique and the three currently known projection methods utilize very different approaches to the mapping construction, both in terms of what structural elements are included and how this information is integrated to produce a vector representation. 相似文献
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A highly-conserved binding pocket on HIVgp41 is an important target for development of anti-viral inhibitors. Holden et al. ( Bioorg. Med. Chem. Lett. 2012, 22, 3011) recently reported 7 experimentally-verified leads identified through a computational screen to the gp41 pocket in conjunction with a new DOCK scoring method (termed FPS scoring) developed in our laboratory. The method employs molecular footprints based on per-residue van der Waals interactions, electrostatic interactions, or the sum. In this work, we critically examine the gp41 screening results, prioritized using different scoring methods, in terms of two main criteria: (1) ligand pose properties which include footprint and energy score decompositions, MW, number of rotatable bonds, ligand efficiency, formal charge, and volume overlap, and (2) ligand pose stability which includes footprint stability (changes in footprint overlap) and rmsd stability (changes in geometry). Relative to standard DOCK scoring, pose property analyses demonstrate how FPS scoring can be used to identify ligands that mimic a known reference (derived here from the native gp41 substrate), while pose stability analyses demonstrate how FPS scoring can be used to enrich for compounds with greater overall stability during molecular dynamics (MD) simulations. Compellingly, of the 115 compounds tested experimentally, the 7 active compounds, as a group, more closely mimic the footprints made by the reference and show greater MD stability compared to the inactive group. Extensive studies using 116 protein–ligand complexes as controls reveal that ligands in their crystallographic binding pose also maintain higher FPS scores and smaller rmsds than do accompanying decoys, confirming that native poses are indeed ‘stable’ under the same conditions and that monitoring FPS variability during compound prioritization is likely to be beneficial. Overall, the results suggest the new scoring method will complement current virtual screening approaches for both the identification (FPS-ranking) and prioritization (FPS-stability) of target-compatible molecules in a quantitative and logical way. 相似文献
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A theoretical approach to the quantitative estimation of the energy of hydrophobic interactions on the molecular level has been developed. The model is based on the fundamental relationship between the probability of shaping of a cavity of the excluded volume in liquid water that results from fluctuations of density and free energy of prime hydrophobic solvates, hard spheres. This probability was estimated with the use of the probabilistic method in combination with experimentally observed data on density and radial distribution function of allocation. Free energy of hydrophobic interactions for a complex consisting of several hard spheres was determined. The critical value of the particles included in the complex was estimated. 相似文献
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PurposeAn indicator of nutrient use efficiency through the entire food chain has been lacking. This article proposes a nutrient footprint method to estimate the efficiency of using both nitrogen (N) and phosphorus (P) in animal production chains following Life Cycle Assessment (LCA). MethodsFollowing the nutrient footprint method of Grönman et al. (2016), we applied the nutrient footprint method to the Finnish beef production and consumption chain. We defined N and P flows associated with the beef chain from a product-specific point of view. The nutrient footprint is a resource efficiency indicator which combines the amount of nutrients captured for use in the production and consumption chain and their nutrient use efficiency (NutUE) either in the primary product or in both the primary + secondary products. Results and discussionEach 1000 kg of Finnish beef consumed requires 1700 kg N and 189 kg P during its life cycle. The percentage of virgin nutrient is more than 50% for N, but only 25% for P. NutUE in the primary product and in both primary + secondary products for N is 1% and 47% and for P is 0.2% and 74%, respectively. ConclusionsThe nutrient footprint offers information about NutUE in a simple and comparable form. In transition towards systems with sustainable nutrient use, it is essential to identify hot spots of nutrient leakage to be able to close them and improve food chains. 相似文献
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The relationship between molecular structure and odor character is one of the most complex structure-activity problems in biology. Despite over a century of effort, it remains unsolved, and synthesis of new odorants still proceeds largely by trial and error. In previous work, I have argued that the reason for this failure lies in a mistaken assumption, namely that molecular shape determines odor character. Instead, I have taken up and extended an old idea (Dyson, 1938) according to which vertebrate olfactory receptors detect odorants by their molecular vibrations. I propose that the detection mechanism is inelastic electron tunnelling. If this is correct, there should be a correlation between the tunnelling vibrational spectra of odorants and their odor character. Here, using semi-empirical quantum chemistry methods and a simple calculation method for tunnelling mode intensities, I calculate the spectra of structurally diverse odorants belonging to various odor categories. With few exceptions, the calculated spectra of bitter almonds, musks, ambers, woods, sandalwoods and violets strongly correlate with odor character. 相似文献
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