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41.
Intention, Goal, Scope, Background Input-Output Analysis (IOA) has recently been introduced to Life Cycle Assessment (LCA). In applying IOA to LCA studies, however,
it is important to note that there are both advantages and disadvantages.
Objectives This paper aims to provide a better understanding of the advantages and disadvantages of adopting IOA in LCA, and introduces
the methodology and principles of the Missing Inventory Estimation Tool (MIET) as one of the approaches to combine the strengths
of process-specific LCA and IOA. Additionairy, we try to identify a number of possible errors in the use of IOA for LCA purposes,
due to confusion between industry output and commodity, consumer’s price and producer’s price.
Method MIET utilises the 1996 US input-output table and various environmental statistics. It is based on an explicit distinction
between commodity and industry output.
Results and Discussion MIET is a self-contained, publicly available database which can be applied directly in LCA studies to estimate missing processes.
Conclusion By adopting MILT results in existing, process-based, life-cycle inventory (LCI), LCA practitioners can fully utilise the process-specific
information while expanding the system boundary.
Recommendations and Outlook MIET will be continuously updated to reflect both methodological developments and newly available data sources. For supporting
information sec http:// wwwJeidenuniv.nl/cml/ssp/softwarc/miet. 相似文献
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43.
Alain Dubreuil 《The International Journal of Life Cycle Assessment》2001,6(5):281-284
Publicly available databases are analysed to demonstrate their relevance to life cycle inventory for energy production in
the Canadian context. Site specific emissions along with sectoral emissions data are combined with production data to construct
an energy production model, which has been applied to air emissions. The allocation procedure leads to reasonable results
for coal, natural gas and electricity. The detailed allocation of the inventory among petroleum co-products is outside the
scope of this study as it requires incorporating knowledge of physical relationship (unit process) or using economic data. 相似文献
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45.
在全球温室气体浓度升高的背景下,如何减少碳排放、增加碳吸收是当前应对气候变化研究的热点.本研究基于我国1963—2016年粗钢产量,采用温室气体清单指南编制方法,建立了钢渣碳汇核算方法,核算了我国1963—2016年钢渣碳汇量,并进行了不确定性分析.结果表明: 1963—2016年间,我国钢渣的年碳汇量总体呈上升趋势,从3.75×103 t C增加至1359.32×103 t C.1963—2016年间我国钢渣累积碳汇量为15×106 t C,钢渣碳汇的总不确定性约为±30.4%.钢渣年碳汇量由当年产钢渣碳汇量和历年产钢渣碳汇量两部分组成.由于钢渣结构致密,年碳化速率较小,导致1963—2016年间当年产钢渣碳汇量较小,占钢渣碳汇总量的37%;历年产钢渣碳汇量较大,占钢渣碳汇总量的63%.虽然钢渣年碳汇量不大,但长期累积碳汇量非常可观,其碳汇作用不容忽视.今后研究应细化不同环境条件下钢渣碳化速率,降低钢渣碳汇核算的不确定性;推动以钢渣为原材料的碳捕集与封存技术发展,增加有效碳汇,为我国应对气候变化国际谈判提供科技支撑. 相似文献
46.
Fernando Diez Marcela Cornelis JosÉ Luis Pall MarÍa Del Carmen CoscarÓn 《分类学与生物多样性》2018,16(6):565-575
The first step to understanding the species present in a particular area is to perform inventory and assemblage studies. To obtain a species inventory, it is important to determine parameters such as species richness and relative abundance. This information can be useful for future studies and decision-making purposes in the conservation area. Despite the fundamental role of the terrestrial Heteroptera in ecosystems, they remain poorly known. We expected that the terrestrial Heteroptera species assemblage would be strongly associated with plant communities. Presently, 840 samples were collected in northern Argentine Patagonia during two years, 2013 and 2014. A total of 1950 adults of terrestrial Heteroptera belonging to 12 families, 32 species, and 8 morphospecies were found. Various statistical techniques were applied to correct the observed data for undersampling bias. These suggested that the lower boundary of the summer Heteroptera species richness in northern Patagonia was about 44–54 species. We concluded that the high regional habitat heterogeneity along the west-to-east and south-to-north gradients was paralleled by the turnover of Heteroptera. However, the Patagonian steppe shared a high number of species with the Monte and Subantarctic provinces. The suction sampling technique is an efficient technique to collect Heteroptera in environments with different plant structure and should thus be used in a complementary way with the sweeping technique. 相似文献
47.
Differential declines in Alaskan boreal forest vitality related to climate and competition 下载免费PDF全文
Anna T. Trugman David Medvigy William R. L. Anderegg Stephen W. Pacala 《Global Change Biology》2018,24(3):1097-1107
Rapid warming and changes in water availability at high latitudes alter resource abundance, tree competition, and disturbance regimes. While these changes are expected to disrupt the functioning of boreal forests, their ultimate implications for forest composition are uncertain. In particular, recent site‐level studies of the Alaskan boreal forest have reported both increases and decreases in productivity over the past few decades. Here, we test the idea that variations in Alaskan forest growth and mortality rates are contingent on species composition. Using forest inventory measurements and climate data from plots located throughout interior and south‐central Alaska, we show significant growth and mortality responses associated with competition, midsummer vapor pressure deficit, and increased growing season length. The governing climate and competition processes differed substantially across species. Surprisingly, the most dramatic climate response occurred in the drought tolerant angiosperm species, trembling aspen, and linked high midsummer vapor pressure deficits to decreased growth and increased insect‐related mortality. Given that species composition in the Alaskan and western Canadian boreal forests is projected to shift toward early‐successional angiosperm species due to fire regime, these results underscore the potential for a reduction in boreal productivity stemming from increases in midsummer evaporative demand. 相似文献
48.
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
49.
Christian Capello Stefanie Hellweg Beat Badertscher Hugo Betschart Konrad Hungerbühler 《Journal of Industrial Ecology》2007,11(4):26-38
Abstract: The software tool ecosolvent is presented that allows for comparative environmental assessment of treatment technologies for specific, user-defined, waste-solvent mixtures. The tool is composed of models for waste-solvent distillation as well as for thermal treatment in hazardous waste-solvent incinerators and cement kilns. It was designed with a tiered structure in order to allow for a high flexibility regarding informational needs. The life-cycle assessment method was used to assess the environmental impact. The applicability of the tool is shown with two case studies from industry. In these case studies, various waste-solvent treatment technologies are compared for two specific waste-solvent mixtures. Potential use of the ecosolvent tool for its role in practical decision making in chemicals industries is illustrated by two case studies of waste-solvent systems. In the ethyl acetate case study, the tool indicates that solvent recovery by distillation is clearly better than incineration of the waste solvent. The results from the methanol case study are less clear-cut. In the subsequent article (part II), the ecosolvent tool will be used to derive general rules of thumb and specific recommendations for 45 important solvents used in chemical industries. Additionally, a framework will be presented that provides quick and easy decision support regarding environmentally optimized waste-solvent management. 相似文献
50.
Soil organic carbon changes in landscape units of Belgium between 1960 and 2000 with reference to 1990 总被引:6,自引:0,他引:6
SUZANNA LETTENS JOS VAN ORSHOVEN BAS VAN WESEMAEL† BART MUYS DOMINIQUE PERRIN‡ 《Global Change Biology》2005,11(12):2128-2140
The present study quantifies changes in soil organic carbon (SOC) stocks in Belgium between 1960, 1990 and 2000 for 289 spatially explicit land units with unique soil association and land‐use type, termed landscape units (LSU). The SOC stocks are derived from multiple nonstandardized sets of field measurements up to a depth of 30 cm. Approximately half of the LSU show an increase in SOC between 1960 and 2000. The significant increases occur mainly in soils of grassland LSU in northern Belgium. Significant decreases are observed on loamy cropland soils. Although the largest SOC gains are observed for LSU under forest (22 t C ha?1 for coniferous and 29 t C ha?1 for broadleaf and mixed forest in the upper 30 cm of soil), significant changes are rare because of large variability. Because the number of available measurements is very high for agricultural land, most significant changes occur under cropland and grassland, but the corresponding average SOC change is smaller than for forests (9 t C ha?1 increase for grassland and 1 t C ha?1 decrease for cropland). The 1990 data for agricultural LSU show that the SOC changes between 1960 and 2000 are not linear. Most agricultural LSU show a higher SOC stock in 1990 than in 2000, especially in northern Belgium. The observed temporal and spatial patterns can be explained by a change in manure application intensity. SOC stock changes caused by land‐use change are estimated. The SOC change over time is derived from observed differences between SOC stocks in space. Because SOC stocks are continuously influenced by a number of external factors, mainly land‐use history and current land management and climate, this approach gives only an approximate estimate whose validity is limited to these conditions. 相似文献