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71.
在计划经济体制下.农业不是也不可能成为一个独立产业,其结果只能是社会效益可观、经济效益甚微甚至倒贴,吃苦的是农民。社会主义市场经济体制的逐步确立,为农业走向市场带来了希望,首要的是确立市场经济观念。丘陵地区大搞农业资源的综合开发是使农业走向市场的重要途径,综合开发上了水平,实现“三高”农业就大有希望。搞农业综合开发的途径很多,但都必须以市场为导向、科技为先导、经济效益为中心,大搞农业产加销一条龙、贸工农一体化是提高农业综合开发整体水平、实现“三高”农业的必要途径。 相似文献
72.
Application of a GIS-based stream buffer generation model to environmental policy evaluation 总被引:3,自引:0,他引:3
Wei-Ning Xiang 《Environmental management》1993,17(6):817-827
In this article a GIS method is presented for riparian environmental buffer generation. It integrates a scientifically tested
buffer width delineation model into a GIS framework. Using the generally available data sets, it determines buffer widths
in terms of local physical conditions and expected effectiveness. Technical burdens of data management, computation, and result
presentation are handled by the GIS. The case study in which the method was used to evaluate the stream buffer regulations
in a North Carolina county demonstrates its capability as a decision support tool to facilitate environmental policy formulation
and evaluation, and environmental dispute resolution. 相似文献
73.
ABSTRACT. In 1970, the Canadian Federal Government passed the Canada Water Act which provides for a co-operative federal-provincial approach to water resource management. The purpose of this paper is to outline our definition of comprehensive planning and the approach being taken under the new legislation. Two basic premises underly the definition. They are that resource management consists of an array of problems and that the prime function of planning is to provide information for decision making. The definition of comprehensive planning is embodied in a general statement and a set of principles. The principles define the approach that should be taken to provide adequate information for decision making in today's complex environment. A brief resume of the jurisdictions for water management in Canada leads to a discussion of a joint federal-provincial comprehensive study of the Qu'Appelle River Basin in Southern Saskatchewan. The basin and the study are described briefly. This is followed by an outline of the economic and social considerations which are being incorporated into the comprehensive planning study for the basin. 相似文献
74.
Resource managers require objective methodologies to optimize decisions related to forest road deactivation and other aspects of road management, especially in steep terrain, where road-related slope failures inflict extensive environmental damage. Decision analysis represents a systematic framework that clearly identifies real options and critical decision points. This framework links current decisions with expected future outcomes and provides advantages such as a common currency to systematically explore the liability consequences of limited budget expenditures to road deactivation and other road-related activities. Furthermore, the decision framework prevents the analysis from becoming hopelessly entangled by the vast number of possibilities generated by the alternative occurrences, magnitudes, and consequences of landslide/debris flow events and provides the information required for the first step of an adaptive management process. Here, a structured analysis of potential environmental risks for a road deactivation project in coastal British Columbia, Canada is presented. The application of decision analysis generates a ranking of the expected benefits of proposed deactivation activities on various road sections. The ranking distinguishes between road sections that offer high expected benefit from those that offer moderate to low expected benefit. Seventeen of 171, 100–m road segments accounted for 18% of the cumulative cost and 98% of the cumulative expected net benefits from road deactivation. Furthermore, the cost of deactivating a section of road is related to the expected benefit from such deactivation, thus providing the basis for more effective resource allocation and budgeting decisions. 相似文献
75.
It is now widely accepted that members of the public should be involved in environmental decision-making. This has inspired
many to search for principles that characterize good public participation processes. In this paper we report on a study that
identifies discourses about what defines a good process. Our case study was a forest planning process in northern New England
and New York. We employed Q methodology to learn how participants characterize a good process differently, by selecting, defining,
and privileging different principles. Five discourses, or perspectives, about good process emerged from our study. One perspective
emphasizes that a good process acquires and maintains popular legitimacy. A second sees a good process as one that facilitates
an ideological discussion. A third focuses on the fairness of the process. A fourth perspective conceptualizes participatory
processes as a power struggle—in this instance a power play between local landowning interests and outsiders. A fifth perspective
highlights the need for leadership and compromise. Dramatic differences among these views suggest an important challenge for
those responsible for designing and carrying out public participation processes. Conflicts may emerge about process designs
because people disagree about what is good in specific contexts. 相似文献
76.
Lake Erie water quality has improved dramatically since the degraded conditions of the 1960s. Additional gains could be made,
but at the expense of further investment and reductions in fishery productivity. In facing such cross-jurisdictional issues,
natural resource managers in Canada and the United States must grapple with conflicting objectives and important uncertainties,
while considering the priorities of the public that live in the basin. The techniques and tools of decision analysis have
been used successfully to deal with such decision problems in a range of environmental settings, but infrequently in the Great
Lakes. The objective of this paper is to illustrate how such techniques might be brought to bear on an important, real decision
currently facing Lake Erie resource managers and stakeholders: the choice of new phosphorus loading targets for the lake.
The heart of our approach is a systematic elicitation of stakeholder preferences and an investigation of the degree to which
different phosphorus-loading policies might satisfy ecosystem objectives. Results show that there are potential benefits to
changing the historical policy of reducing phosphorus loads in Lake Erie. 相似文献
77.
Using Multicriteria Methods in Environmental Planning and Management 总被引:12,自引:0,他引:12
In environmental planning and decision processes several alternatives are analyzed in terms of multiple noncommensurate criteria,
and many different stakeholders with conflicting preferences are involved. Based on our experience in real-life applications,
we discuss how multicriteria decision aid (MCDA) methods can be used successfully in such processes. MCDA methods support
these processes by providing a framework for collecting, storing, and processing all relevant information, thus making the
decision process traceable and transparent. It is therefore possible to understand and explain why, under several conflicting
preferences, a particular decision was made. The MCDA framework also makes the requirements for new information explicit,
thus supporting the allocation of resources for the process. 相似文献
78.
79.
Aslı Aksoy 《International Journal of Green Energy》2019,16(1):34-48
All economic sectors are associated with energy use; therefore, government organizations aim to supply sustainable energy for human needs and economic growth. In particular, increased environmental concerns of the public in Turkey have impacted policymaking for renewable energy (RE) management in Turkey. The primary objective for RE sources of the Turkish Ministry of Energy is to ensure that 30% of the share of electricity production is from RE resources in 2023. In this paper, the integrated multi-objective, multi-period linear programming model is presented to determine effective allocation of RE supply for seven different geographical regions in Turkey for the period of 2017 to 2024. The integrated model consists of two different stages. The first stage involves qualitative evaluations of RE sources for seven geographical regions. Analytical Hierarchy Process (AHP) is applied to determine criteria priorities and overall ratings of geographical regions across determined criteria for RE sources are computed. The second stage of the integrated model consists of a multi-objective, multi-period linear programming model. The proposed multi-objective linear programming model is coded in MPL (Mathematical Programming Language) and solved using the GUROBI 5.1.0 solver. The output of the integrated model presents the total supply amount of RE sources for geographical regions in planning period. The ε-constraints method is applied to compute the total supply amount of RE from geographical regions for the period of 2017 to 2024. In this study, a systematic decision-making model is generated to allocate renewable energy sources to the geographical regions. The presented model integrates qualitative evaluations and quantitative parameters of different geographical regions to determine the optimal supply amount of RE. The obtained results are consistent with the potential quantities of RE alternatives in geographical regions, regional specifications, and social requirements. 相似文献
80.
Noel D. Uri 《Environmental management》1980,4(5):375-380
A myriad of factors, both economic and political, influenced the voting by members of the United States Congress on the 1978 National Energy Act. Determinant factors considered in our analysis included the percentage of residents in the Congressman's district residing in the central city or on farms; the percentage of residents who belong to labor unions; the average level of education of the residents; oil, coal, and natural gas production in the state relative to total domestic production. The results, determined by means of logit analysis, indicate that the impact on low-income energy consumers, the effect on overall employment, the impact on farmers, and the benefits to energy interests, as well as ideology and the subjective perception that the need exists to do something about the energy situation in the United States, were all important explanatory factors.The author is an economist with the United States Department of Energy. The views expressed are those of the author and do not necessarily represent the policies of the Department of Energy or the views of other Department of Energy staff members. 相似文献