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791.
针对四川石油天然气工业环境统计中存在的非稳定污染源监测数据的统计价值不高,统计调查方法单一,个别统计指标计算未使用国家统一标准等现状,从环境监测站改组入手,改革统计调查方法,建立以必要的周期性普查为基础,以经常性的抽样调查为主体,同时辅之以全面统计报表,重点调查和科学推算综合运用的统计调查方法体系。  相似文献   
792.
/ This study intended to explore the perceptions of mountain bikingmanagement through a mail survey of state park directors in all 50 states.With a 100% response rate, it was found that 47 states permit mountainbiking in their state parks, however, few state parks have formalized plansto manage this outdoor activity. The management policies that do exist arenot followed on a statewide basis but vary within each state and at eachstate park. Many states have worked cooperatively with local mountain bikingclubs to develop and maintain mountain bike trails, promote rider education,and provide volunteer patrols on trails. The issue of user conflict surfacedwith almost three-fourths of the managers responding that conflict existedbetween mountain bikers and other trail users. This preliminary study shouldprompt further research with on-site managers focusing on the use ofmanagement plans for mountain biking, cooperation between managers and usergroups, and user conflict. It is recommended that an Internet-basedinformation clearinghouse or discussion group be made available to landmanagers by a national bicycling organization.KEY WORDS: Mountain biking; State parks; State park directors;Recreation resource management  相似文献   
793.
This paper develops the idea that the principle of equitable utilization must be applied in concert with sustainable water use not only in the resolution of specific disputes but in the cooperative management of water resources in general. It illustrates this point with two different cases involving the use of the Danube River. The first is the conflict over the Gabcikovo Nagymaros Dam, which now rests before the International Court of Justice. The author argues that a narrow legal ruling that fails to take into account broader issues of equitable utilization as they relate to sustainable development will not satisfactorily address the long-term questions at stake between the parties. The second involves the situation in the Danube Delta where the potential for conflict exists, but may be minimized through the convention and institutional framework developed to address the environmental degradation and pollution of the Danube River basin, which is based in part on the principle of equitable utilization and the goal of achieving more sustainable water use. The paper provides a brief overview of the geographical features of the Danube River and international water law. It then explores the principle of equitable utilization and sustainable water use in light of the two cases and discusses the implications for the resolution and management of conflicts involving internationally shared water courses.  相似文献   
794.
A Sensitivity Analysis of Nitrogen Losses from Dairy Farms   总被引:2,自引:0,他引:2  
International attention has focused on agricultural production systems as non-point sources of pollution affecting the quality of streams, estuaries and ground water resources. The objective of the current study was to develop a model of nitrogen management on the dairy farm, and to perform sensitivity analyses in order to determine the relative importance of manipulating herd nutrition, manure management and crop selection in reducing nitrogen (N) losses from the farm. The importance of the method of N input to the farm (purchased feed, legume fixation, inorganic fertilizer, imported manure) was investigated, and the potential to reduce N losses from dairy farms was evaluated. Nitrogen balance equations were derived, and related efficiency coefficients were set to reference values representing common management practices. Total farm N efficiency (animal product N per N input), and N losses per product N were determined for different situations by solving the set of simultaneous equations. Improvements in animal diet and management that increase the conversion of feed N to animal product by 50% would increase total farm N efficiency by 48% and reduce N losses per product by 36 to 40%. In contrast, reducing losses from manure collection, storage and application to improve the percentage of manure N that becomes available in soil by 100% would only improve total farm N efficiency by 13% and reduce total N losses by 14%. Selecting crops and management that can use soil nutrients 50% more efficiently would improve total farm efficiency by up to 59% and reduce N losses by up to 41% depending on the predominant nitrogen sources to the farm. Legume production would reduce N losses per product compared with non-legumes. There was more than a five fold difference in N losses per animal product N between the most extreme scenarios suggesting considerable opportunity to reduce N losses from dairy farms.  相似文献   
795.
大庆地区水体环境的水生生物调查结果与评价   总被引:2,自引:0,他引:2  
结合区域工业污染源的构成特点,对分布在油田的13个湖库进行了浮游生物和底栖动物的调查,从生物学角度,科学地评价了各类水体的污染程度,为保护和合理开发利用地表水资源,污染源的优化管理,实现污染物的总量控制提供了科学依据。  相似文献   
796.
从综合治理,合理利用采出污水的长远利益出发,针对东部油田高含水阶段的新特点,提出地面高效处理,地下控水稳油相结合的治理策略,探讨了相关的技术和方法,并讨论了采出污水回注利用中应加强研究的几个问题。  相似文献   
797.
本文论述了淮河下游地区常绿针叶林、落叶阔叶林,落叶常绿阔叶混交林,竹林等森林资源类型的特征,分析了该地区森林资源在经营管理中存在的问题,提出了应采取的森林资源经营管理对策。  相似文献   
798.
环境医学:人类生存发展战略的大课题   总被引:1,自引:0,他引:1  
王承鳌 《四川环境》1997,16(1):23-26
文章用大量翔实数据,分析论证:人类由于淡化环境意识,坚持急功近利的片面发展观,造成整个地球环境质量正在全面下降和恶化,全球已有1/5的人口受到环境污染之害的基点上,作者提出了只有跳出以自我生存为中心的狭隘圈,确立发展环境医学为主体的预防医学战略,并提示要遵循中国古代强调的“天人合一”论概念和钱学森提出的“开放的巨系统方法论”在当代科技领域进行“天地生人巨系统的综合集成研究”,树立“天地与我并生,万物与我同运”的自然生态观,为创建“生物心理社会自然”为模式的全科新医学,这是实现21世纪“人类健康工程”的开拓性目标。  相似文献   
799.
本文通过对岷江干流(成都段)地表水和地下水的综合研究,分别提出了地表水污染防治对策和地下水水质防护措施,划分出了地表水防治不同时期的目标以及地下水开采管理目标。  相似文献   
800.
ABSTRACT: Accurate data about nutrient concentrations in wastewater treatment plant effluents are needed for river basin water-quality studies. As part of the U.S. Geological Survey's National Water-Quality Assessment Program in the South Platte River Basin, nutrient data were requested from 31 wastewater-treatment plants located in the basin. This article describes the types of nutrient data available from the plants, examines the variability of effluent nutrient concentrations, and discusses methods for estimation of nutrient concentrations where data are lacking. Ammonia was monitored at 88 percent of the plants, nitrite plus nitrate was monitored at 40 percent of the plants, and organic nitrogen and phosphorus were monitored at less than 25 percent of the plants. Median total nitrogen concentrations and median total phosphorus concentrations were small compared to typical literature estimates for wastewater-treatment plants with secondary treatment. Nutrient concentrations in effluent from wastewater-treatment plants varied widely between and within plants. For example, ammonia concentrations varied as much as 5 mg/L during a day, as much as 10 mg/L from day to day, and as much as 30 mg/L from summer to winter within a plant. In the South Platte River Basin, estimates of median annual ammonia and nitrite plus nitrate concentrations can be improved based on plant processes; and nitrite plus nitrate and organic nitrogen concentrations can be estimated based on ammonia concentrations. However, to avoid large estimation errors, more complete nutrient data from wastewater-treatment plants are needed for integration into river basin water quality studies. The paucity of data hinders attempts to evaluate the relative importance of point source and nonpoint source nutrient loadings to rivers.  相似文献   
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