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151.
For lowering sediment, nitrogen (N) and phosphorus (P) pollution of surface water bodies at the catchment scale, environmental legislation require programs of pollution abatement measures. To be able to ensure the cost-effectiveness of such programs we first need to identify high risk areas, which give rise to increased pollutant runoff. Process-based GIS models provide the opportunity to identify such critical areas and hence better target diffuse pollution abatement actions. However, these models are data intensive and their spatially-distributed parameterization in poorly monitored catchments is not feasible without extensive input data pre-processing and significant simplifying assumptions. This study implements the widely-used SWAT river basin model (Soil Water Assessment Tool) to study a medium-sized Greek catchment with the typical data limitations met at the national level, in order to identify critical diffuse pollution source areas that may serve as the key areas for meeting the objective of ‘good ecological status’ of water bodies set by the European Water Framework Directive (WFD). Model parameterization and evaluation are presented along with the decisions made to overcome problems related to data representation in the catchment, in an effort to provide guidance on SWAT modeling in areas with similar characteristics. The results show that sediments and nutrients could be adequately reproduced in large time steps (monthly or seasonal) and that even with the current data limitations, the seasonal variation and the most critical areas of pollutant losses to waters could be adequately identified. The study proposes a transparent modeling approach under data limitations without neglecting possible deficiencies; however, it maintains that the SWAT model, if appropriately parameterized with respect to the land-use and soil differentiation within a limited-gauged catchment, can still facilitate the selection and placement of suitable practices across the landscape for a cost-effective diffused pollution management.  相似文献   
152.
PROBLEM: Traumatic brain injury (TBI) is a public health problem but little is known about the nature of that problem in the working population. METHOD: The author used a national definition to identify cases in Washington State from workers' compensation (WC) hospital billing data, quantified the cost of WC insurance benefits using actuarial cost estimates, and identified high risk industries using ANSI Z16.2 typology. RESULTS: There were 928 cases of TBI with a lifetime claim cost of $159 million from the Washington State Fund (1994-2001). Sixty percent of injuries resulted in death or disability. The highest risks of TBI are concentrated in 16 industrial insurance risk classes and the highest costs in 19 North American Industry Classification codes. Injury scenarios were identified for nine industrial insurance risk classes. CONCLUSIONS: TBI is a disabling and costly workplace injury in the state of Washington, affecting even teenagers and seniors who are not generally considered to be part of the workforce. Injury typology codes provide useful information for improving workplace safety. IMPACT ON INDUSTRY: This research provides industry with quantitative information regarding the cost of work-related traumatic brain injury and the usefulness of using workers' compensation claims data to reduce the burden of workplace injury.  相似文献   
153.
Abstract: Environmental synergisms may pose the greatest threat to tropical biodiversity. Using recently updated data sets from the International Union for Conservation of Nature (IUCN) Red List, we evaluated the incidence of perceived threats to all known mammal, bird, and amphibian species in tropical forests. Vulnerable, endangered, and extinct species were collectively far more likely to be imperiled by combinations of threats than expected by chance. Among 45 possible pairwise combinations of 10 different threats, 69%, 93%, and 71% were significantly more frequent than expected for threatened mammals, birds, and amphibians, respectively, even with a stringent Bonferroni‐corrected probability value (p= 0.003). Based on this analysis, we identified five key environmental synergisms in the tropics and speculate on the existence of others. The most important involve interactions between habitat loss or alteration (from agriculture, urban sprawl, infrastructure, or logging) and other anthropogenic disturbances such as hunting, fire, exotic‐species invasions, or pollution. Climatic change and emerging pathogens also can interact with other threats. We assert that environmental synergisms are more likely the norm than the exception for threatened species and ecosystems, can vary markedly in nature among geographic regions and taxa, and may be exceedingly difficult to predict in terms of their ultimate impacts. The perils posed by environmental synergisms highlight the need for a precautionary approach to tropical biodiversity conservation.  相似文献   
154.
本文旨在探讨集合最优插值(EnOI)同化方法对MM5-STEM空气质量模式污染物浓度预报场的修正能力,先从局地化尺度(L)及经验系数(α)的敏感性试验中获得NO2、SO2和PM10各自的"最优L和α组合",然后对此参数设置下的同化结果进行分析.研究结果显示,EnOI在NO2、SO2及PM10的同化试验中均取得较好的效果,检验站点均方根误差(RMSE)的平均下降比例分别可达33%、32%和42%,RMSE值下降的站点占检验站点总数的比例分别为86%、84%和91%.表明该方法能够有效地应用在珠三角空气质量模拟中,产生与实际更为接近的污染物浓度预报场.  相似文献   
155.
从建设项目环境保护管理、环境监测、环境应急、生态保护以及环境监察等方面阐述无人机遥感技术在环境保护领域中的应用现状,并对无人机影像的后期处理常用方法及最新发展动向进行了阐述。总结了目前无人机遥感技术在环境保护领域中存在的问题,对数据后处理技术研究方向作出展望。  相似文献   
156.
Reliability data acquisition and evaluation in process plants   总被引:1,自引:0,他引:1  
Based on the practical experience of assessing reliability data in two plants of the explosives industry, the organization and scope of the data collection, the component delimitation, the procedures of quality assurance and the data evaluation for their final use in PSA studies are presented. An example is given for the type of detection and repair, etc. The mathematical background for evaluating observed component lifetimes is discussed. Both frequentist and Bayesian methods are addressed. The resulting failure rate distributions and their approximations by log-normal distributions for several key components are presented. They were obtained using a Bayesian approach with a non-informative prior. Remarks on uncertainty, their treatment and a proposal for transferring data to plants other than the ones investigated conclude the presentation.  相似文献   
157.
吉林省环境数据中心管理系统建设初探   总被引:1,自引:0,他引:1  
田阳光  潘瑜  李媛  李曦 《四川环境》2011,30(1):139-142
本文简述建立环境数据中心的必要性及其在信息化建设中的地位与作用,论证了吉林省环境数据中心管理系统建立的环境基础及可行性并提出了设想和建议。  相似文献   
158.
In the hard rock areas of India, overdraft of groundwater has led to negative externalities. It increased costs of groundwater irrigation and caused welfare losses. At the same time informal groundwater markets are slowly emerging and are believed to improve water distribution and to increase water use efficiency in the irrigation sector. These claims are evaluated in this study. For this purpose data was collected from a sample containing three different groups of water users: water sellers, water buyers and a control group of non-traders. First the socio-economic characteristics of these groups are compared. Then the efficiency of water use of the three groups is studied using Data Envelopment Analysis. The results indicate that groundwater markets provide resource poor farmers access to irrigation water, giving them the opportunity to raise their productivity. Water buyers are furthermore shown to be most efficient in their water use, while water sellers are also shown to be more efficient than the control group. The differences in efficiency between the groups are statistically significant. The demonstrated potential of groundwater markets to improve the efficiency of water use and to increase equity in resource access should be taken into account by the Indian government when deciding on their attitude towards the emerging groundwater markets.  相似文献   
159.
农田施用水葫芦对水稻干物质生产与分配的影响   总被引:4,自引:0,他引:4  
为促进农田养分循环利用和农业生态环境健康,以粳稻品种运2645为供试材料,设计农田施用水葫芦(将晒干水葫芦按4 500 kg hm-2农田施用)和不施用水葫芦处理(对照),施N量为120 kg hm-2(LN)、240 kg hm-2(NN),研究其对水稻物质生产与分配的影响.结果表明:1)农田施用水葫芦使水稻移栽~分蘖中期、分蘖中期~拔节期、拔节~抽穗期、抽穗期~穗后20 d和穗后20 d~成熟期平均分别比对照8.6%、9.8%、12.2%、15.9%和3.1%,使得成熟期生物产量显著增加(+9.0%);2)与干物质生产量相似,水稻平均叶面积指数(LAI)和净同化率(NAR)对水葫芦处理的响应呈相似的季节性变化趋势,但NAR在穗后20 d~成熟期有所下降;3)农田施用水葫芦对水稻不同生育时期叶片、茎鞘和稻穗占地上部干重的比例影响不大;4)增加施N量能够明显增加水稻的干物质生产量;水葫芦×N的互作效应对水稻干物质生产与分配无明显影响.5)农田施用水葫芦使水稻生育前、中期干物质生产量增幅较大,对生育后期影响相对较小.图5表3参15  相似文献   
160.
随着烟气排放连续监测系统(CEMS)的广泛安装和验收,CEMS数据的应用将成为污染源管理最直接最有效的手段.在国家规定的数据有效性审核基础上,结合实际工作遇到的问题和长期实践经验,提出每日审核对于数据有效性的重要作用,并通过上海市特有的CEMS数据审核机制,介绍该审核机制的建立背景、内容、流程及取得的成果.  相似文献   
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