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961.
李正方 《生态与农村环境学报》1996,(2)
对有机食品的基本概念和有机食品所必需具备的条件作了概要的介绍,并对国内外有机食品的发展概况、我国发展有机食品的有利条件作了较全面的论述和分析。在此基础上,提出了我国有机食品开发的原则、策略和开发中值得注意的一些问题和建议。 相似文献
962.
揭阳市生态农业发展的思路 总被引:1,自引:0,他引:1
分析了揭阳市生态农业发展的现状、有利条件及制约囚素,总结了对该市发展生态农业有积极影响的揭东县塔西种养场生态种养模式,最后提出了该市生态农业的发展模式、发展思路和对策。 相似文献
963.
Based on the soil moisture data from the locating experiments from 1986—1990, and using the water balance method, the water supply and demand state in the field of winter wheat, and the ways for improving water condition in dryland of dry subhumid area of the Loess Plateau were studied. The results suggested that a low precipitation satisfying ratio of 42.9%—58.8% appears in the growing period of winter wheat, and the yield, to a great extent depended on the water that was stored in deep soil layer in the previous rainy season. The filed trial results showed that tillage in the summer fallow period,straw cover, soil moisture regulation with adequate fertilization, crop rotation and proper cropping system could be the efficient ways for improving the water condition,and for the exploitation and utilization of natural water resources(both precipitation and soil water) in the winter wheat field of dryland. 相似文献
964.
浙江省农业地质环境信息系统建设初探 总被引:1,自引:0,他引:1
应用计算机技术、地理信息系统技术、遥感技术以及系统科学的理论和方法建立农业地质环境信息系统,可以实现对农业地质环境信息的收集、存储、加工、使用、动态更新、统计分析和辅助决策。该系统不但为农业地质环境项目的科学管理提供标准化、信息化,为社会提供信息共享服务,也极大提升了农业地质环境动态监测管理和决策的科学性。结合浙江省农业地质环境信息系统建设实践,本文对农业地质环境信息管理系统建设的内容、方法以及应用前景进行了初步探讨。 相似文献
965.
持续农业带来现代农业的新方向,但仅局限于物理环境的改善不能实现农业的持续性。只有重视环境问题的社会性因素,寻求解决社会与环境问题的新方法,才能真正保持农业的持续发展。 相似文献
966.
Rosenzweig C. Tubiello F. N. 《Mitigation and Adaptation Strategies for Global Change》1997,1(3):219-232
Current trends in Mediterranean agriculture reveal differences between the Northern and Southern Mediterranean countries as related to population growth, land and water use, and food supply and demand. The changes in temperature and precipitation predicted by general circulation models for the Mediterranean region will affect water availability and resource management, critically shaping the patterns of future crop production. Three companion papers analyze in detail future impacts of predicted climate change on wheat (Triticum aestivum L.) and maize (Zea mays L.) production in Spain, Greece, and Egypt, and test farm- level adaptation strategies such as early planting and cultivar change with the aid of dynamic crop models. Strategies to improve the assessment of the potential effects of future climate change on agricultural production are discussed. 相似文献
967.
Fred J. Brenner James J. Mondok 《Journal of the American Water Resources Association》1995,31(6):1101-1112
ABSTRACT: A 155,947 ha portion of the Shenango River watershed in western Pennsylvania was evaluated as to the potential impact of agriculture drainage on water quality. Approximately a third of the area is being used as either cropland or pasture with approximately an equal percentage in forest lands. Eleven subwatersheds were evaluated as to their potential for nonpoint source pollution according to the criteria established by the Pennsylvania Department of Environmental Resources for the Chesapeake Bay Pollution Abatement Program. The individual components and overall rating for each subwatershed were then evaluated as to their correlation with four water quality variables based on 104 samples collected at 26 sampling stations throughout the watershed. There was a significant correlation between the overall rating factor for each subwatershed and each of the four water quality variables. In general, the watershed delivery factor, animal nutrient factor, and management factors were correlated with fecal coliform and phosphorus in the receiving streams, whereas the ground water delivery factor appeared to be more important in determining nitrate concentrations in these streams. These results indicate that manure and nutrient management, along with the exclusion of livestock from streams and the enhancement and/or replacement of riparian wetlands, are important approaches in reducing agricultural impacts in fresh water ecosystems. 相似文献
968.
Miguel A. Altieri 《Natural resources forum》2000,24(2):97-105
The great majority of farmers in Latin America are peasants who still farm small plots of land, usually in marginal environments utilizing traditional and subsistence methods. The contribution of the 16 million peasant units to regional food security is however substantial. Research has shown that peasant systems, which mostly rely on local resources and complex cropping patterns, are reasonably productive despite their small land endowments and low use of external inputs. Moreover analysis of NGO-led agroecological initiatives show that traditional crop and animal systems can be adapted to increase productivity by biologically re-structuring peasant farms which in turn leads to optimization of key agroecosystem processes (nutrient cycling, organic matter accumulation, biological pest regulation, etc.) and efficient use of labour and local resources. Examples of such grassroots projects are herein described to show that agroecological approaches can offer opportunities to substantially increase food production while preserving the natural resource base and empowering rural communities. 相似文献
969.
Because the agriculture/food sectors appear to be driven by short-term economic and political forces, cheap energy, and agricultural-chemical technologies, waste and environmental/social problems in the agricultural/food sectors are estimated to cost the nation at least $150 billion per year. Most of the waste and environmental/social problems can be eliminated through better resource management policies and the adoption of sustainable agricultural practices.Based on a paper entitled Waste in U.S. Agricultural and Food Sectors—Environmental and Social Costs presented at the Gross National Waste Product Forum, Washington, D.C. 相似文献
970.
文章综合分析了影响泸定县农业生态系统因素间的关系,建立了评价与决策分析层次模型。通过层次模型判断矩阵的运算,求出各层次因素相对目标层重要性的合成权值,并在此基础上评价泸定县农业资源生态系统的效益水平和优选该系统建设决策措施实施的最佳顺次结构。 相似文献