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381.
对钻井废物污染的全过程控制 总被引:4,自引:1,他引:4
在钻井作业过程中控制废物的排放量和毒性,变末端处理为全过程控制,采取各种措施预防钻井废物的污染是近年来国外油气田环保工作的一项重要内容。本文就采用小井眼钻井工艺;减少井眼冲蚀;强化环境管理;提高钻井液固控系统的处理效率;开发各种合成基钻井液;采用低毒无害的钻井液化学添加剂等6个方面讨论了减少钻井废物产生量的途径和降低钻井液及添加剂对环境的影响 相似文献
382.
The Toxics Release Inventory (TRI) created by the 1986 Emergency Planning and Community Right-to-Know Act initially received
limited attention. During the early years of its implementation, the TRI has become the basis for a national experiment in
voluntaristic problem solving among citizens and industry, but that process of environmental democracy hinges on citizens'
ability to actually acquire, understand, and apply the new data on industrial toxic emissions. A national study of TRI-using
organizations in the public and private sectors reveals that effective citizen access depends in part on the efforts of intermediary
public interest groups to bridge individual needs and right-to-know data. Although the TRI has had early success as a supplement
to conventional command and control regulation, questions exist about the extent to which state and federal government should
or must provide special efforts to make environmental information access work for citizens. 相似文献
383.
Sensitivity indices, which rank factors pertinent to surface and subsurface runoff pathways, were used to identify phosphorus
source areas in riparian zones of 15 northern Minnesota lakes. Watershed models were first developed using a geographic information
system (GIS). Empirical models were then developed correlating water quality with land use, lake morphometry, and riparian
sensitivity. Base models of forested, cultivated, pasture/open, wetland and residential land use within 100, 200, 400, and
2000 m of the study lakes were regressed on total phosphorus and chlorophyll-a. Area-weighted groundwater and surface runoff sensitivity indices were then incorporated into each model and tested for significance.
Within the 200-m buffer, the total phosphorus base model was improved by including the groundwater index alone. The chlorophyll-a base model at 200 m was improved by including: (1) the groundwater index alone, and (2) both the groundwater and surface
runoff sensitivity indices. Results suggest that surface and subsurface runoff analysis of potential source areas can improve
decision making for lake riparian management. 相似文献
384.
自然灾害灾情划分指标研究 总被引:6,自引:1,他引:6
本文阐述了灾情分析中的两个基本方面,即损失的规模和损失的深度,提出了灾级和灾度的概念,对于影响灾级和灾度的主要指标也进行了分析。并就时间和空间变化对灾级划分界线的影响作了论述。 相似文献
385.
Fred J. Brenner William Kanour Bruce Weston Gerald Valerio Kenneth R. Grayburn 《Environmental management》1986,10(2):241-253
A study of the impact of two flood control reservoirs and pollution influx was conducted on two streams within the Sandy Creek Watershed, Mercer County, Pennsylvania, USA. Fecal coliforms were significantly reduced in the outflows without affecting water chemistry, thereby improving the overall water quality. The size and composition of the aquatic communities as well as stream metabolism varied seasonably among the different sampling stations. Pollution influx primarily from communities and agricultural drainage had a greater impact on the stream ecosystem than did impounding of the streams. Natural wetlands and riparian vegetation were important factors in reducing the pollution load in these streams. The reestablishment and maintenance of riparian vegetation should therefore be an integral part of the land-use plan for watersheds in order to improve water quality and wildlife habitats. In the future, the maintenance of riparian vegetation should be given prime consideration in the development of watershed projects. 相似文献
386.
A comparative study of water pollution emissions of pulp and paper companies for the period 1978–1983 indicates a reduction in emissions for most firms. This improvement in pollution performance is attributed to the federal government's water pollution policy. Although there is an overall decline in water pollution, some firms have actually increased their emissions. Furthermore, there is still a wide disparity in each company's performance, although the differences are narrowing. 相似文献
387.
In the last ten years official location policy in Nigeria for urban roadside traders, an enterprising group of urban poor operating at the lowest level of the informal sector of the economy has been very negative. Government believes that they should be removed from the streets and tucked away in obscure locations because of their tendency to deface the streets with litter and for causing vehicular and pedestrian traffic congestion. This paper identifies and assesses the magnitude of pollution created by the traders as a prelude to evolving a planning policy and strategy for regulating and formally accommodating street traders in good locations while still ensuring good environmental quality. 相似文献
388.
389.
Fertilizer Management in Watersheds of Two Ramsar Wetlands and Effects on Quality of Inflowing Water
Two field experiments were carried out in the watersheds of two Ramsar wetland areas, Lakes Koronia and Volvi (area A) and
Lakes Mikri and Megali Prespa (area B), to study the effect of application of N fertilizer on wheat yields, the quality of
runoff water, and the quality of stream water. The treatments were a combination of two methods of fertilizer application
(total amount in fall, and 2/3 in fall + 1/3 in spring) at three rates (0, 100, and 200 kg N/ha) with four replications. Concentrations
of NH4
+, NO3
−, NO2
−, P, and Cl− and pH were determined in all water samples. Runoff water quality was not influenced by fertilizer application in either
area. Chemical parameters for water did not differ along the selected watercourses in area B, while in area A they were higher
in the samples taken near Lake Koronia than in the samples taken upstream, indicating that the watercourses are polluted downstream
by nonagricultural sources. The differences in wheat yields between the 100 and 200 kg N/ha application rates were not high.
These results call for better fertilizer management in order to achieve better yields and to diminish the possibility to have
negative effects to the environment. 相似文献
390.
Nazzareno Diodato 《The Environmentalist》2006,26(1):63-70
Summary Seasonal rainerosivity is important in the structure and dynamics of Mediterranean ecosystems. The present paper contributes
to the quantitative assessment of RUSLE's monthly erosion index in a data-scarce Mediterranean region. Therefore, a regionalized
relationship for estimating monthly erosion index (EI30-month) from only three rainfall parameters has been obtained. Knowledge of the seasonal and annual distribution of erosivity index,
permit soil and water conservationists to make improved designs for erosion control, water harvesting or small hydraulic structures.
Although a few long data sets were used in the analysis, validation with established monthly erosivity index values from other
Italian locations, suggest that the model presented (r2 = 0.973) is robust. It is recommended to monthly erosivity estimates when experimental data-scarce rainfall become available. 相似文献