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991.
Soil erosion and non-point source pollution impacts assessment with the aid of multi-temporal remote sensing images 总被引:10,自引:0,他引:10
Soil erosion associated with non-point source pollution is viewed as a process of land degradation in many terrestrial environments. Careful monitoring and assessment of land use variations with different temporal and spatial scales would reveal a fluctuating interface, punctuated by changes in rainfall and runoff, movement of people, perturbation from environmental disasters, and shifts in agricultural activities and cropping patterns. The use of multi-temporal remote sensing images in support of environmental modeling analysis in a geographic information system (GIS) environment leading to identification of a variety of long-term interactions between land, resources, and the built environment has been a highly promising approach in recent years. This paper started with a series of supervised land use classifications, using SPOT satellite imagery as a means, in the Kao-Ping River Basin, South Taiwan. Then, it was designed to differentiate the variations of eight land use patterns in the past decade, including orchard, farmland, sugarcane field, forest, grassland, barren, community, and water body. Final accuracy was confirmed based on interpretation of available aerial photographs and global positioning system (GPS) measurements. Finally, a numerical simulation model (General Watershed Loading Function, GWLF) was used to relate soil erosion to non-point source pollution impacts in the coupled land and river water systems. Research findings indicate that while the decadal increase in orchards poses a significant threat to water quality, the continual decrease in forested land exhibits a potential impact on water quality management. Non-point source pollution, contributing to part of the downstream water quality deterioration of the Kao-Ping River system in the last decade, has resulted in an irreversible impact on land integrity from a long-term perspective. 相似文献
992.
将华莺山建设成为川东生态屏障 总被引:2,自引:0,他引:2
生态环境保护是环保工作的重要内容,是实地西部大开发的主要工程之一。本文就控制环境污染、保护生物多样性、提高植被覆盖率论述了环境保护与生态环境建设的关系,并依据华蓥山系存在的生态环境问题,阐明了加强环境保护与川东生态屏障建设的基本对策。 相似文献
993.
Edwin T. Engmun 《Journal of the American Water Resources Association》1974,10(3):512-521
ABSTRACT: According to a concept known as partial area hydrology, watershed areas are separated into hydrologically active and passive subareas. The literature relating to the development of the partial area concept is reviewed briefly and the relationship of partial area hydrology to geology, soils, and micrometeorology is illustrated. The potential application of partial area hydrology is discussed with respect to present hydrologic techniques, future hydrologic models, urban hydrology, water quality, and water management. Suggestions for identifying and delineating the contributing areas are discussed. 相似文献
994.
日本于2012年10月1日正式颁布了《环境教育等促进法》,此法由2003年颁布的《有关增进环保意愿以及推进环保教育的法律》修改而来,是一部充分调动各个社会主体协同合作,用环境教育开展环境保护工作的法律。通过分析该法多角度分层次的教育措施及特点,借鉴日本多年来环境教育推广经验,对我国加快环境教育立法进程,实现全民环境教育,增强全民节约意识、生态意识、环保意识,全力建设美丽中国有着重大意义。 相似文献
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996.
通过分析目前环境监测站监测档案建立和运用中存在的问题,探讨了档案的建立方法及在环境监测和环境管理中的运用。 相似文献
997.
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999.
Brian P. Leaderer Rebecca T. Zagraniski Jan A. J. Stolwijk 《Environmental management》1977,1(1):31-37
A method is presented here by which the actual numbers of individuals in the U.S. population who would be expected to suffer respiratory illness as a result of exposure to ambient nitrogen dioxide (NO2) concentrations in excess of the Federally-designated ambient air quality standard can be estimated. At the same time we have attempted to quantify how these adverse health effects would be alleviated by various degrees of reductions in current ambient concentrations. In addition, the health benefit expected to be derived by various NOx emission control strategies will be examined utilizing the health benefit estimation method presented.It is estimated that there were approximately 33.2×106 excess cases of respiratory illnesses in the U.S. in 1973 associated with ambient NO2 concentrations in excess of the national ambient standard. A reduction of approximately 50 to 60 percent below 1973 NO2 levels is needed to essentially eliminate excess respiratory illness associated with ambient NO2 concentration. 相似文献
1000.