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811.
为确保炼油厂设备安全而稳定地运行,各生产装置都要定期进行停工检修,在此期间排放的污染物对环境将产生一定的影响。停工检修中的环保工作包括实施环保措施;加强环境管理;并且将2000m~3隔油池由一间式变为两间式,提高污水处理率和达标率。 相似文献
812.
The National Forest Management Act (1976) specifies that multiresource inventories be conducted to provide baseline data for
development and, later, monitoring of national forest management plans. This mandate entails the most ambitious and complex
resource planning effort ever attempted. In this paper we evaluate the structure and use of current inventory-monitoring programs
and recommend a framework for gathering data to improve national forest planning. Current national guidelines are general
and provide only basic directions to forest-level planners. Forest inventories have traditionally concentrated on timber.
Although these inventories are often well designed, the questions we are now asking about forest resources have outgrown these
methods. Forest management is impeded by general confusion over definitions of resources and the interactions among them.
We outline a simple classification scheme that centers on identification of basic ecosystem elements that can be readily measured.
Furthermore, spatial and temporal scales must be considered in the design of inventory-monitoring programs. The concept of
ecological indicators is reviewed, and caution is advised in their use. Inventory-monitoring programs should be goal-directed
and based on as rigorous a statistical design as possible. We also review fundamental issues of variable selection, validation,
and sampling bias. We conclude by developing a flexible inventory-monitoring program that is designed to provide information
on individual characteristics of the environment, rather than being based on fixed definitions of resources. 相似文献
813.
Stephen P. Mumme 《Environmental management》1995,19(6):827-835
United States-Mexican transboundary water resources management is presently experiencing significant reform resulting from
long-term demographic processes in the border region and greater economic integration. The recently concluded North American
Free Trade Agreement and supplementary environmental accord modify existing agreements and provide old institution with new
mandates. Particularly affected is the International Boundary and Water Commission (IBWC), long the lead agency in binational
water management. This essay reviews the development of the new water management regime against the two preceding phases of
management reform and considers its implications for improved water management in the border region. 相似文献
814.
Carlos Wing-Hung Lo 《Environmental management》1995,19(3):331-344
Within the context of political democratization, this article explores environmental protection in Hong Kong since the government
lauched a ten-year program to “save the environment” in 1989. Examining environmental management by law from a social-choice
perspective, it argues that the government has yet to reach an integrative policy orocess. Hence the preconditions for an
integrative set of environmental legislation are absent. Institutionally, without a comprehensive green policy, the current
arrangements lack a vision as an integrative force to promote effective coordination among various sectoral environmental
coordination among various sectoral environmental programs. The dominant approach of policy and law enforcement through consultation
has rendered impossible strict enforcement of environmental rules and regulations as local economic growth enjoys a priority
over environmental protection. At a time of environmental awakening, the people of Hong Kong are not yet prepared awakening,
the people of Hong Kong are not yet prepared to participate in environmental management in a strict legal manner. The overall
observation is that Hong Kong has yet to see more mature political, legal, administrative, and social conditions for managing
its environment within a legal framework. 相似文献
815.
Venkateswara R. Rao 《Environmental management》1995,19(3):313-320
Risk management practices under the current environmental regulations is a long, complex process that considers scientific,
technologic, and management factors to develop various regulatory standards and pollution control measures. Using the mandatory
enforcement approach, sometimes referred to as “command-and-control”, a set of preliminary environmental goals, such as better
air and water qualities, were achieved. However, the information-intensive nature of the risk management process and the lack
of flexibility in conventional regulatory methods to changing economic and technologic realities of the decade has created
interest among risk managers to examine some innovative management approaches. Above all, environmental problems of a global
scale require novel management methods while striving to achieve the desired environmental goals.
As the principal analytical tool in risk management, quantitative risk assessment exerts considerable influence on the risk
management process. Therefore, advances in risk management are closely associated with scientific developments that enhance
the risk assessment process, particularly those efforts aimed at improving human exposure and toxicity assessments. Market
incentives, information dissemination, creative enforcement practices, and interagency and intergovernmental interactions
were identified as the key elements of innovative environmental risk management practices. This paper will present an overview
of the emerging innovative risk management approaches. 相似文献
816.
817.
电解法处理高含硫气田水 总被引:1,自引:0,他引:1
本文详细介绍了川南矿区含硫气田水电解法处理的试验情况,用自己研制的电解反应器对电解时间、pH值、电流密度等工艺条件进行了考察,提出了电解法处理含S~(2-)200mg/L的气田水的最佳工艺条件。试验结果表明:该方法是成功的,它可以使气田水中硫化物的脱除率达99%以上,达到国家排放标准(GB8978—88:S~(2-)<5mg/L)。该方法的主要特点是投加处理药剂少,操作简便,设备小型,占地面积小,特别适用于产水量不大的井站使用。 相似文献
818.
ABSTRACT: Because of its importance and the perceived inability of private sector sources to meet water demands, many countries have depended on the public sector to provide water services for their populations. Yet this has resulted in many inefficient public water projects and in inadequate supplies of good quality and reliable water. Decentralization of water management, including the use of water markets, cannot solve all of these water problems, but it can improve the efficiency of water allocation. When given adequate responsibility and authority, water user associations have effectively taken over water management activities at a savings to tax payers. Moreover, water markets add the potential benefit of improving water efficiency within a sector as well as providing a mechanism for reallocating water among sectors. The key question involves developing innovative mechanisms for reducing the transaction costs of organizing water users and of making water trades. Water rights need to be established which are recorded, tradable, enforceable, and separate from land if markets are to operate effectively. Also, institutions are needed that effectively resolve conflicts over water rights, including third party impacts and water quality concerns. 相似文献
819.
Lee H. MacDonald James A. Hoffman 《Journal of the American Water Resources Association》1995,31(1):79-95
ABSTRACT: Both catchment experiments and a review of hydrologic processes suggest a varying effect of forest harvest on the magnitude of peak flows according to the cause of those peak flows. In northwestern Montana and Northeastern Idaho, annual maximum flows can result from spring snowmelt, rain, mid-winter rain-on-snow, or rain-on-spring-snowmelt. Meteorologic and physical data were used to determine the cause of annual maximum flows in six basins which had the necessary data and were smaller than 150 mi2. Rain-on-spring-snowmelt was the most frequent cause of annual maximum flows in all six basins, although there was a strong gradient in the magnitude and cause of peak flows from southwest to northeast. Less frequent mid-winter rain-on-snow events caused the largest flows on record in four basins. Mid-winter rain-on-snow should be distinguished from rain-on-spring-snowmelt because of differences in seasonal timing, the relative contributions of rain vs. snowmelt, and the projected effects of forest harvest. The effects of mixed flood populations on the flood-frequency curve varied from basin to basin. Annual maximum daily flows could not be reliably predicted from rainfall and snowmelt data. 相似文献
820.
William W. Walker 《Journal of the American Water Resources Association》1995,31(4):671-685
ABSTRACT: The State of Florida (1994) has adopted a plan for addressing Everglades eutrophication problems by reducing anthropogenic phosphorus loads. The plan involves implementation of Best Management Practices in agricultural watersheds and construction of regional treatment marshes (Stormwater Treatment Areas or STA's). This paper describes the development, testing, and application of a mass-balance model for sizing STA's to achieve treatment objectives. The model is calibrated and tested against peat and water-column data collected in Water Conservation Area-2A (WCA-2A), where phosphorus dynamics and eutrophication impacts have been intensively studied. The 26-year-average rate of phosphorus accretion in peat is shown to be proportional to average water-column phosphorus concentration, with a proportionality constant of 10.2 m/yr (90 percent Confidence Interval = 8.9 to 11.6 m/yr). Spatial and temporal variations in marsh water-column data suggest that drought-induced recycling of phosphorus was important during periods of low stage in WCA-2A. Maintaining wet conditions will be important to promote phosphorus removal in STA's. Sensitivity analysis of STA performance is conducted over the range of uncertainty in model parameter estimates to assess the adequacy of the model as a basis for STA design. 相似文献