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921.
ABSTRACT: The project described in this report was undertaken by the Louisiana State Planning Office to establish the extent of backwater flooding in Louisiana in April 1975. Band 7 Landsat imagery, enlarged to a scale of 1:250,000 was used to visually identify flooded areas. Inundated areas were delineated on overlays keyed to 1:250,000 U.S. Geological Survey topographic quadrangles. Tabular data identifying acres flooded, according to land use type, were derived by merging the flood map overlays with computerized 1972 land use data. Approximately 1.12 million acres of the state were inundated by flood waters. The total acreage and land use types affected by flooding were determined within 72 hours from the time the flood areas were imaged. Flooded maps were prepared for 26 parishes. Field observations were made by Louisiana Cooperative Extension Service county agents in order to determine the accuracy of parish flood maps and flood acreage figures by land use type. Results indicated that this was a fast, accurate, and relatively inexpensive method of compiling flood data for disaster planning and postflood analysis.  相似文献   
922.
通过学习贯彻《职业安全健康管理体系的指导意见》和《职业安全健康管理体系审核规范》,阐述了学习体会和实际应用中的建议。  相似文献   
923.
As freshwater becomes increasingly scarce due to population growth, urbanisation and, probably, climate change, the use of wastewater in agriculture, aquaculture, groundwater recharge and in other areas will increase. In some cases, wastewater is the only water resource available to poor, subsistence-level farming communities. Although there are benefits to using wastewater in agriculture—such as better nutrition and food security for many households—uncontrolled use of wastewater is frequently associated with significant negative human health impacts. These health impacts can be minimized when good management practices are implemented. In this paper the existing situation, in relation to water resources availability, wastewater treatment and reuse in Morocco and Palestine, is presented.  相似文献   
924.
Spatial proximity of emissions sources to receptors may affect sensitivity to potential adverse human health effects. This research investigates whether receptor sensitivity to the location of emission sources can be utilized efficiently to minimize health risk in selecting sites for industrial enterprises, thermal electric stations, etc. A sensitivity function that is independent of the location of pre-existing emission sources is derived and applied to Minsk, Belarus. The function estimates exposures based on weather and climatic conditions as well as the distribution of population density at a given locality. Arraying prospective sites based on their sensitivity function magnitude provides a technique for minimizing health risk based on receptor sensitivity to the spatial proximity of atmospheric emissions sources.  相似文献   
925.
Environmental decision-making and policy-making at all levels refers necessarily to synthetic, approximate quantification of environmental properties such as vulnerability, conservation status, and ability to recover after perturbation. Knowledge of such properties is essential to informed decision-making, but their definition is controversial and their precise characterization requires investments in research, modeling, and data collection that are only possible in the most developed countries. Environmental agencies and governments worldwide have increasingly requested numerical quantification or semiquantitative ranking of such attributes at the ecosystem, landscape, and country level. We do not have a theory to guide their calculation, in general or specific contexts, particularly with the amount of resources usually available in such cases. As a result, these measures are often calculated with little scientific justification and high subjectivity, and such doubtful approximations are used for critical decision-making. This problem applies particularly to countries with weak economies, such as small island states, where the most precious environmental resources are often concentrated. This paper discusses frameworks for a “least disappointing,” approximate quantification of environmental vulnerability. After a review of recent research and recent attempts to quantify environmental vulnerability, we discuss models and theoretical frameworks for obtaining an approximate, standardizable vulnerability indicator of minimal subjectivity and maximum generality. We also discuss issues of empirical testing and comparability between indicators developed for different environments. To assess the state of the art, we describe an independent ongoing project developed in the South Pacific area and aimed to the comparative evaluation of the vulnerability of arbitrary countries.  相似文献   
926.
Assessing Landscape Health: A Case Study from Northeastern Italy   总被引:17,自引:0,他引:17  
This article investigates the concept of biophysical landscape health for what are termed “highly governed landscapes.” It proposes a definition of landscape health along with a preliminary diagnostic model and methods. The idea of landscape health derives from the emerging integrative science of ecosystem health, which seeks to diagnose ecosystem condition as humans diagnose human health. Highly governed landscapes, such as the reclaimed areas of coastal northeastern Italy, are landscapes that have been subject to even greater degrees of human manipulation than normal cultural landscapes. These highly altered landscapes are not easily served by existing environmental paradigms and concepts of health are seen to have numerous advantages. This paper condenses a broader investigation of landscape health into three main sections. A brief review of the literature is followed by a case study, which details two different phases of landscape transformation in the Lower Piave area of northeastern Italy. A definition and general parameters of biophysical landscape health are then presented after this background stage. Some key parameters of biophysical health include absence of distress and risk factors, sustainability, biodiversity, resilience, and balance. For certain parameters, a preliminary landscape health diagnostic framework is presented that includes potential diagnostic methods and thresholds based on findings from this case study. At the paper's conclusion, a summary diagnostic model is presented, which suggests a process needed to implement landscape health assessment into practice.  相似文献   
927.
研究了含硫"类二噁英"化合物多氯代二苯并噻吩(PCDTs)中的2,3,7,8-四氯代二苯并噻吩(2,3,7,8-TCDT)在锦鲫(Carassius auratus)不同组织中的生物富集规律和对肝脏的氧化损伤.结果表明,2,3,7,8-TCDT在锦鲫各组织中的富集能力表现为肝脏>鳃>肌肉.2,3,7,8-TCDT在锦鲫...  相似文献   
928.
Multiple negotiating rounds of the General Agreement on Tariffs and Trade (GATT) and World Trade Organization (WTO) since 1947 have conferred economic benefits through liberalized international trade. A growing body of evidence also points to linkages between liberalized trade and damage to the global environment, ecology, and natural resource base. Ironically, the increased economic well-being conferred by trade liberalization ultimately provides the basis for improved environmental protection. It is the interim environmental damage due to trade liberalization that is controversial and needing amelioration. The proposition here is to promote further trade liberalization, but only as long as environmental ethics and sustainability issues are satisfactorily addressed. Trade liberalization should not be permitted at the expense of adequate environmental protection and sustainability. Future WTO rounds need to address both development benefits and environmental ethics issues in a net social welfare maximization setting.  相似文献   
929.
彗星试验的改良及其在工业废水监测中的应用   总被引:1,自引:0,他引:1       下载免费PDF全文
为了探讨彗星试验在工业废水监测中的应用,本文将常规的细胞暴露方式改良为浸泡染毒,既提高了实验的敏感性,又使得该试验直接用于监测工业废水的遗传毒性成为可能.作者用改良彗星试验直接检测了几种工业废水所引起的V79细胞DNA损伤.结果表明,所测的各种工业废水均含有DNA损伤剂,能够诱发培养的V79细胞DNA链断裂,其中以制革厂废水的DNA损伤作用最强.本研究显示出改良彗星试验在综合评价各种废水遗传毒性方面的广阔应用前景.  相似文献   
930.
推行OHSMS过程中管理责任制的探讨   总被引:1,自引:1,他引:0  
结合石油、天然气行业建立 HSE(健康、安全、环境 )管理体系的实践 ,归纳了在企业推行职业安全卫生管理体系 (OHSMS)过程中运用管理责任制的基本内容 ;根据领导科学和安全科学理论 ,采取与实际分析相结合的方法 ,论述了推行 OHSMS过程中安全管理责任制的必要性、科学性和适用性。  相似文献   
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