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381.
本文介绍了农业产业化的基本理论,分析了汕头经济特区的经济现状与问题,并提出了汕头经济特区发展农业产业化的建议。 相似文献
382.
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
383.
黄河三角洲农业开发与可持续发展研究 总被引:2,自引:0,他引:2
本文分析了黄河三角洲农业开发的有利条件、开发现状和存在的主要问题,探讨了农业生产的合理布局,提出了农业可持续发展的对策. 相似文献
384.
J. G. Arnold R. Srinivasan R. S. Muttiah J. R. Williams 《Journal of the American Water Resources Association》1998,34(1):73-89
ABSTRACT: A conceptual, continuous time model called SWAT (Soil and Water Assessment Tool) was developed to assist water resource managers in assessing the impact of management on water supplies and nonpoint source pollution in watersheds and large river basins. The model is currently being utilized in several large area projects by EPA, NOAA, NRCS and others to estimate the off-site impacts of climate and management on water use, non-point source loadings, and pesticide contamination. Model development, operation, limitations, and assumptions are discussed and components of the model are described. In Part II, a GIS input/output interface is presented along with model validation on three basins within the Upper Trinity basin in Texas. 相似文献
385.
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
386.
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
387.
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
388.
Adesoji Adelaja Donn Derr Karen Rose-Tank 《Journal of Agricultural and Environmental Ethics》1989,2(2):97-112
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
389.
ABSTRACT: A soil erosion simulation model that considered the physical conditions of agricultural watersheds and that interfaced with the modified USDAHL-74 watershed hydrology model was developed. The erosion model simulates the detachment and transport of soil particles caused by raindrop impact and overland flow from rill and interrill areas. The model considers temporal and spatial variation of plant residue, crop canopy cover, snow cover, and the moisture content of surface soil as modifying factors of the erosive forces of raindrop impact and overland flow. The hydrology model simulates overland flow and some of the physical parameters that are used in the erosion model. The simulation is executed in the time interval determined by the rainfall rate or snowmelt rate. The erosion model compares the transport capacity of the overland flow and the sediment loaded in the overland flow to determine the fate account for the free soil particles that have already been detached and are readily available to be transported by the overland flow. The model was tested with data from two small agricultural watersheds in the Palouse region of the Pacific Northwest dryland. The model was calibrated by trial-and-error to determine the coefficients of the model. 相似文献
390.
The Thar Desert of western India is known for its rich and ancient culture system and traditions. The communities have long
been part of the Thar Desert ecosystem and have evolved specific strategies to live in harmony with its hostile environment.
This culture has provided several miracle plants of immense food and medicinal value to modern civilisation. The ancient rural
livelihood knowledge system reflects time-tested techno-scientific knowledge with a proven track record of sustainability,
especially during natural hazards like drought and famines. In addition, several of the traditional skills of local communities
in arts and crafts, music and instruments have made modern man aware of the art and techniques of sustainably utilising local
biological resources and preserving their biodiversity along with using waste products of the forests, without harming the
desert ecosystem. Traditional cultural and socio-religious values are fast dwindling under the impact of materialistic approach,
industrialisation and development. This paper endeavours to illustrate the need to assist and propagate indigenous rural livelihood
systems rather than mindlessly replace or abandon them as a result of state bureaucracies. 相似文献