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91.
A variable density sampling pattern based on Bayesian statistics is presented and compared to a uniform density statistical pattern and a judgmental approach in a real case study. The Bayesian statistics, supported by a software tool, supplied a soil sampling plan similar to the judgmental one, especially for the number of sampling points and their location. It allowed statistical goals to be set and expert judgment to be included in the sampling strategy in a transparent and systematic procedure. For these reasons, it appears quite suitable for inclusion into Quality Assurance Quality Control plans. 相似文献
92.
我国北方植被指数对土壤湿度的敏感性分析 总被引:7,自引:0,他引:7
土壤湿度对植被指数起着重要的作用。利用NOAA-AVHRR数据中的植被指数(NDVI)和我国气象台站所监测的土壤湿度数据,对我国北方地区的NDVI与土壤湿度的关系进行了研究。结果表明,近18年来,北方地区土壤湿度不同区域其变化趋势存在差异,西北地区土壤湿度在增加,而华北和东北地区土壤湿度在下降。NDVI对土壤湿度的响应也存在着明显的区域差异,我国西北地区植被对土壤湿度的敏感性最强,其次是华北地区,敏感性弱的是东北地区;对于不同层次的土壤湿度,也表现为同样的区域特点。但随着土壤深度的增加,敏感性减弱。这种敏感性也表现在不同季节变化上,春季华北地区土壤湿度对植被指数影响较大,其次是西北和东北地区,夏季和秋季北方地区土壤湿度与植被指数都有较好的相关性,以西北地区的相关系数最大,而冬季北方地区植被指数对土壤湿度都不敏感。 相似文献
93.
《Journal of Industrial Ecology》2004,8(1-2):11-21
Land use is an increasingly important component of sustainability evaluations, and numerous performance metrics have evolved to meet this need. The selection of appropriate land-use metrics for decision makers, however, remains an ongoing challenge. Additionally, life-cycle practitioners often struggle to provide meaningful impact assessment because of challenges associated with traditional land-use impact metrics. This article is intended to assist decision makers and life-cycle practitioners who wish to more effectively measure and evaluate one aspect of land use: surface area occupation. Existing performance metrics are discussed, and the specific circumstances under which each is appropriate are identified. Building on leading-edge research and analysis in the field of life-cycle impact assessment, a modified methodology for evaluating surface area occupation is proposed. This approach is demonstrated for a series of mining practices including three individual gold mines, a bauxite mine, and a copper mine. The specific data requirements and resulting equivalency factors for each mine are discussed. Results indicate that equivalency factors for gold (average of 700 acre-yr/ton) are expected to be several orders of magnitude higher than for either bauxite (0.004 acre-yr/ ton) or copper (0.03 acre-yr/ton). These dramatic differences in results demonstrate that equivalency factors are appropriate and necessary for including land-use impact potential as part of a life-cycle assessment that includes several different minerals or material requirements. 相似文献
94.
Cáassia?M.?L.?UgayaEmail author Arnaldo?C.?S.?Walter 《The International Journal of Life Cycle Assessment》2004,9(6):365-370
Data acquisition to perform LCA is time and capital consuming. There is already international data about environmental aspects
in several processes. This study aims to verify the possibility of adapting international data to Brazilian conditions. Therefore,
a Life Cycle Inventory was conducted to compare the use of national and international data for steel used in automobiles.
This was done in three steps: objective and scope definition, inventory analysis and interpretation. LCI is a simplification
of Life Cycle Assessment (LCA) as impact assessment is not taken into account. Even so, LCI takes into account all life cycle
stages of a product, that is, from its extraction through its deposition. In this study, three phases of the life cycle were
considered: steel manufacturing, automobile use and disposal. In the case studied, the amount of steel evaluated was 263 kg,
which would be possible to be replaced by other materials in a 1,300 kg automobile. Resources and energy consumption, atmospheric
emissions and solid residues production were taken into account within the analysis done. Results show that automobile use
and materials manufacturing are responsible for the bulk of energy and resources consumption. Solid residues occur mainly
in the discard phase, due to the low level of recycling. Several differences were also achieved between national and international
data, which implies the need of environmental databases development. 相似文献
95.
We applied the floristic quality index (FQI) to vegetation data collected across a chronosequence of created wetland (CW) sites in Virginia ranging in age from one to 15 years post-construction. At each site, we also applied FQI to a nearby forested reference wetland (REF). We tested the performance of the index against a selection of community metrics (species richness, diversity, evenness, percent native species) and site attributes (age, soil physiochemical variables). FQI performed better when non-native species (C-value = 0) were removed from the index, and also when calculated within rather than across vegetation layers. A modified, abundance-weighted FQI showed significant correlation with community and environmental variables in the CW herbaceous layer and REF herbaceous and shrub-sapling layers based on Canonical correspondence analysis (CCA) ordination output. These results suggest that a “natives only”, layer-based version of the index is most appropriate for our region, and an abundance-weighted FQI may be useful for assessing floristic quality in certain layers. The abundance-weighted format has the advantage of preserving the “heritage” aspect of the species conservatism concept while also entraining the “ecology” aspect of site assessment based on relative abundances of the inhabiting species. FQI did not successfully relate CW sites to REF sites, bringing into question the applicability of the FQI concept in comparing created wetlands to reference wetlands, and by analogy, the use of forested reference wetlands in general to assess vegetation development in created sites. 相似文献
96.
Heather E. Wright Qiong Zhang James R. Mihelcic 《The International Journal of Life Cycle Assessment》2008,13(5):412-420
Goal, Scope, and Background The paper describes the integration of the economic input–output life cycle assessment (EIO-LCA) model and the environmental
fate and transport model (CHEMGL) with a risk assessment tool. Utilizing the EIO-LCA, instead of a traditional LCA, enables
a rapid, screening-level analysis of an emerging chemical of concern, decabromodiphenyl ether (DecaBDE). The risk assessment
in this study is evaluated based on the mass of chemical released, estimated concentrations, exposure, and chemical toxicity.
Methods The relative risk from ten economic sectors identified within the EIO-LCA model, 55 chemicals utilized in those sectors and
DecaBDE along with four potential DecaBDE breakdown products, were evaluated for the life cycle stages and exposure pathways.
The relative risk (expressed as toluene equivalents) of the different chemicals, sectors, and life cycle stages were compared
to assess those representing the greatest overall relative risks to humans (via inhalation and ingestion) and fish.
Results The greatest overall risk to human health resulted from the manufacturing and production stages. For fish, the manufacturing
stage represented virtually all of the risk. Of the 56 chemicals evaluated, DecaBDE represented the majority of the total
risk to humans. However, DecaBDE posed the least risk compared to its potential breakdown products.
Discussion The risk to humans from ingestion, which represented the greatest risk, from the production, manufacturing, and consumption
stages can be controlled and reduced through various safety precautions in the workplace. Additionally, the increasing concentration
of DecaBDE in anaerobic compartments represents a threat to humans and fish via the higher risk DecaBDE breakdown products.
Conclusions Overall, the manufacturing and production life cycle stages pose the greatest risk to humans and fish. The sediment compartment
received the highest DecaBDE concentration for the production, manufacturing, and consumption stages. This case study demonstrates
that the integrated EIO-LCA with risk assessment is suitable for screening-level analysis of emerging chemicals due to rapid
life cycle inventory analysis.
Recommendations The production and manufacturing stages allow for greater industry control and government regulation, compared to the consumption
stage, because there are fewer point sources. This integrated life cycle methodology may allow chemical designers to evaluate
each stage and assess areas where risks can be minimized. 相似文献
97.
98.
《Revista espa?ola de geriatría y gerontología》2023,58(1):35-42
Last decade, the Government of Catalonia have urged an integrated care strategy for planning the care model to older populations living with frailty, multimorbidity and advanced illnesses. Based on international evidence that was reviewed by a group of experts from the Catalan Society of Gerontology and Geriatrics, we summarised some recommendation to adapt hospital-at-home care to older populations in our system. We defined Comprehensive Geriatric Assessment (CGA) hospital-at-home (HaH) as a specialised home hospitalisation service formed by interdisciplinary teams, characterised by using the clinical methodology of CGA, and by adapting geriatric units’ protocols for the provision of person-centred care at home. Main benefits of CGA-HaH in these populations are: response to heath crises according to individualised care plans based on the situational diagnosis carried out by Primary Care teams; provision of a comprehensive health and social approach tailored to the complexity of cases and situations; and adaptation of multipurpose hospitalisation, by working on different person-centred care, aspects, such as caregivers support on care provision, focusing on function or home adaptation. 相似文献
99.
Exploration of environmental changes relates to lifestyle 总被引:2,自引:0,他引:2
Mettke-Hofmann Claudia; Wink Michael; Winkler Hans; Leisler Bernd 《Behavioral ecology》2005,16(1):247-254
Decision making in informed animals is often described by optimalitymodels. However, how information about an environment is acquiredis rarely investigated. Cost/benefit considerations suggestthat species differ in this respect according to their lifestyle.We tested the hypothesis that resident species react to changesin their familiar environment earlier and explore it more intensivelythan do nomadic species by observing the response to environmentalchanges (presentation of novel objects) in 10 parrot species.Phylogenetic relationships were taken into account. Residentstouched the novel objects significantly earlier and exploredmore objects than did nomads. In addition, species with a highproportion of fruits in their food spectrum explored more thandid species with other food preferences. The results are inaccordance with different costs and benefits of informationgathering for species that differ in their lifestyle and ecologicaldemands. 相似文献
100.
Very-broad-scale assessment of human impacts on river condition 总被引:2,自引:0,他引:2
RICHARD H. NORRIS SIMON LINKE IAN PROSSER WILLIAM J. YOUNG PETER LISTON NICHOLAS BAUER NERIDA SLOANE FIONA DYER MARTIN THOMS 《Freshwater Biology》2007,52(5):959-976
1. Management of whole rivers and river catchments requires a comprehensive set of information about river condition and use, both existing and historical, and the links between them at regional, state or national scales. This paper outlines a new approach to the assessment of river condition, using a small team was able to assess 210 000 km of rivers across more than 3 million km2 of Australia in little more than a year. 2. The approach was driven by a hierarchical model of river function, which assumed that broad‐scale catchment characteristics affect local hydrology, habitat features, water quality and, ultimately, aquatic biota. The model provided the basis for selecting important ecologically relevant features that indices should represent. For each reach of each river we derived a biological index and an environmental index based on measures quantifying catchment and hydrological condition, and habitat and water quality condition. Data came from existing state and national databases, satellite images, site measurements and process models. 3. All indices were calculated as deviation from a reference condition, were range‐standardised and were divided into equivalent bands of condition. Amalgamation of index components and of sub‐indices was determined by consideration of their ecological effects; for example, general degradation might be additive, but toxic effects of one component would override all others. 4. Several internal and external validation methods were employed, with the all‐important validation of the final assessments undertaken by comparison with a similar index based on locally measured data. 5. The environmental assessment classified 14% of reaches as largely unmodified, 67% as moderately modified and 19% as substantially modified by human impacts. The biological assessment based on site assessments and modelled data using invertebrates indicated that 70% of reaches were equivalent to reference condition and that 30% were significantly impaired. Catchment disturbance, elevated sediment and nutrient loads, and habitat degradation all contributed to these results. These impacts have all occurred during the last 200 years (post‐European settlement). 6. Partly as a result of the assessments of this study the Australian Government has begun to adopt a more environmentally sustainable approach to broad‐scale water management. 相似文献