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461.
Strategies to involve agribusiness in the development of sustainable agricultural systems have been limited by the lack of a comprehensive conceptual framework for identifying the most critical supportive policies, programs and regulations. In this paper, we propose an efficiency/substitution/redesign framework to categorize strategies for modifying agribusiness practices. This framework is then used to identify a diverse range of short, medium, and long-term strategies to be pursued by governments, community groups, academics and agribusiness to support the transition. Strategies discussed include corporate greening, ethical investment, changing the legal status of the corporaton, new business forms and the development of ecological economics.  相似文献   
462.
ABSTRACT: Short-term fluctuations in agricultural markets necesitate adjustments in market prices for use in water resources planning. Two procudures for this price normalizing are described and evaluated. The linear treand and weighted average normalizing procedures perform reasonably well, except in cases of dramatic price oscillations.  相似文献   
463.
ABSTRACT: The increased agricultural efficiency of the American farmer has been a substantial impetus to this nation's rapid urbanization. In many western regions where total water supplies are limited, urbanization has required the transfer of heretofore agricultural water rights to the urban use. A major problem in such transfers has been the value or price of the water. A management level model of a typical urban water system was developed to optimize water supply, distribution, and wastewater treatment alternatives. The values of agricultural transfers were determined as the cost advantages of increasing allowable reuse levels of urban effluents which imply the use of a downstream right. This procedure is justified by the economic theory of alternative cost. Results for a test application to the Denver, Colorado area indicate values on the order of $1,000 per acre-foot of transferable water depending on effluent water quality restrictions and operational policies.  相似文献   
464.
Considerations of virtue and character appear from time to time in the agricultural biotechnology literature. Critics of the technologies often suggest that they are contrary to some virtue (usually humility) or do not fit with the image of ourselves and the human place in the world that we ought to embrace. In this article, I consider the aretaic or virtue-based objection that to engage in agricultural biotechnology is to exhibit arrogance, hubris, and disaffection. In section one, I discuss Gary Comstock's treatment of this objection. In section two, I provide an alternative interpretation of the objection that more accurately reflects the concerns of those who offer the criticism than does Comstock's standard interpretation. In sections three and four, I assess the objection. I argue that despite its merits, the objection does not justify global opposition to agricultural biotechnology. Instead, it favors a limited endorsement position not unlike the one defended by Comstock.  相似文献   
465.
ABSTRACT: The term flashiness reflects the frequency and rapidity of short term changes in streamflow, especially during runoff events. Flashiness is an important component of a stream's hydrologic regime. A variety of land use and land management changes may lead to increased or decreased flashiness, often to the detriment of aquatic life. This paper presents a newly developed flashiness index, which is based on mean daily flows. The index is calculated by dividing the pathlength of flow oscillations for a time interval (i.e., the sum of the absolute values of day‐to‐day changes in mean daily flow) by total discharge during that time interval. This index has low interannual variability, relative to most flow regime indicators, and thus greater power to detect trends. Index values were calculated for 515 Midwestern streams for the 27‐year period from 1975 through 2001. Statistically significant increases were present in 22 percent of the streams, primarily in the eastern portion of the study area, while decreases were present in 9 percent, primarily in the western portion. Index values tend to decrease with increasing watershed area and with increasing unit area ground water inputs. Area compensated index values often shift at ecoregion boundaries. Potential index applications include evaluation of programs to restore more natural flow regimes.  相似文献   
466.
本文分析了福建省农业自然资源利用中存在的突出问题及其形成原因,并根据持续发展新模式提出了持续利用的对策。  相似文献   
467.
陕南秦巴山地农业资源立体专业化开发利用   总被引:4,自引:0,他引:4  
本文对秦巴山地农业环境特点、资源构成和分异规律进行了系统分析,提出了农业地域专业化开发利用的原则和模式.  相似文献   
468.
本文提出了农业生产潜力指数评价的基本理论和方法,并利用这一评价方法对内江市主要家业作物的生产潜力的进行了评价分析。  相似文献   
469.
谢良成 《四川环境》1994,13(4):45-48
本文论述了水土水流失对生态环境的影响和对农业生产的危害,阐明增强环境意识,加强水土保持时防止生态恶化,是我国振兴农业的重要性与紧迫性的任务。  相似文献   
470.
A cash-flow viability model is used to evaluate the impacts of land-use zoning on farm households in New Jersey. Findings suggest that zoning results in increased production expenses, lower efficiency and profitability, and the devaluation of land assets. Cash flow and economic viability are, thus, reduced. Impacts of zoning on farm incomes, off-farm incomes, revenues from land sales, indebtedness, and farm sizes were not statistically significant. The results suggest that the use of land-use zoning statutes to guarantee the existence of agriculture may not be equitable unless transferable development rights or other methods of compensating farmers for their losses are simultaneously implemented.  相似文献   
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