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982.
Kazuo Kamura Yu Hara Bulent Inanc Masato Yamada Yuzo Inoue Yusaku Ono 《Journal of Material Cycles and Waste Management》2005,7(2):66-70
It is always possible for impermeable layers to exist in landfills. When they do, the properties of the solution at the exit of the leachate-collection system might not accurately reflect the overall properties of the landfill. This study examines whether resistivity monitoring is effective for determining the influence of impermeable layers on the leachate. The test cell used in this study was filled with waste made up mainly of incinerator ash and shredded incombustible material. Three lines of resistivity sensors were laid in the uppermost layer of the fill. A resistivity profile was recorded periodically from each of these lines. The water-table level and leachate properties were measured concurrently. Leachate conductivity was mainly controlled by concentrations of the main ions, and it correlated inversely to variations in resistivity. Temporal changes in the resistivity of the fills are an excellent means of assessing the leaching in fills. Monitoring the properties of leachate, combined with resistivity profiling, is extremely useful for interpreting the temporal changes of properties in landfills containing impermeable layers. 相似文献
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987.
针对传统的污染排放数据指标计算方法存在的问题,提出污染物排放指标应根据排污强度和经济指标确定的新思路,同时提出污染物排放指标数据的快速测算模型设计.建议通过环境监测数据或物料衡算数据确定每个排污单位的平均排污强度,作为计算机处理的参数,再由该排污单位申报每月的经济指标(产量或产值),输入计算机计算其产污量、排污量和去除量.实施计算机管理的关键是选取适当的数据计算模型.新思路应该能够规范计算程序,建立污染源动态数据库,对排污数据实行有效的统计分析. 相似文献
988.
大气环境影响评价工作分级要求要点 总被引:1,自引:0,他引:1
根据大气环境影响评价工作的分级要求,提出了针对性的工作要点,以满足大气环境评价工作的需要. 相似文献
989.
A study of a watershed planning process in the Cache River Watershed in southern Illinois revealed that class divisions, based
on property ownership, underlay key conflicts over land use and decision-making relevant to resource use. A class analysis
of the region indicates that the planning process served to endorse and solidify the locally-dominant theory that landownership
confers the right to govern. This obscured the class differences between large full-time farmers and small-holders whose livelihood
depends on non-farm labor. These two groups generally opposed one another regarding wetland drainage. Their common identity
as “property owner” consolidated the power wielded locally by large farmers. It also provided an instrument – the planning
document – for state and federal government agencies to enhance their power and to bring resources to the region. The planning
process simultaneously ameliorated conflicts between government agencies and the large farmers, while enhancing the agencies’
capacity to reclaim wetlands. In this contradictory manner, the plan promoted the environmental aims of many small-holders,
and simultaneously disempowered them as actors in the region’s political economy.
An erratum to this article is available at . 相似文献
990.
The Water Fluxes of the Yellow River to the Sea in the Past 50 Years, in Response to Climate Change and Human Activities 总被引:12,自引:1,他引:12
Jiongxin X 《Environmental management》2005,35(5):620-631
Since the 1970s, the water fluxes to the sea of the Yellow River have declined significantly. Based on data of precipitation, air temperature, the measured and “natural” river flow, the water diversion and consumption, and the areas of erosion and sediment control measures over the drainage basin, water fluxes to the sea of the Yellow River are studied in relation with the influences of changing climate and human activities. The Yellow River basin can be divided into different water source areas; multiple regression indicates that the variation in precipitation over different water source areas has different effect on water fluxes to the sea. In the period between 1970 and 1997, averaged air temperature over the whole Yellow River increased by about 1.0°C, from 16.5°C to 17.5°C, a factor that is negatively correlated with the water yield of the Yellow River. Water diversion and consumption has sharply increased and resulted in a significant decline in the water fluxes to the sea. Since the 1960s, erosion and sediment control measures have been practiced over the drainage basin. This factor, to a lesser degree, is also responsible for the decrease in water fluxes to the sea. A multiple regression equation has been established to estimate the change in water fluxes to the sea caused by the changes in precipitation, air temperature, water diversion and consumption, erosion, and sediment control measures, indicating that the contribution of water diversion and consumption to the variation in annual water flux to the sea is 41.3%, that of precipitation is 40.8%, that of temperature is 11.4%, and that of erosion and sediment control measures is 6.5%. 相似文献