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排序方式: 共有1311条查询结果,搜索用时 15 毫秒
91.
我国农业县(市)绿色食品发展对策研究   总被引:8,自引:1,他引:7  
发展绿色食品是实现区域可持续发展和发展生态农业的一条有效途径。本文分析了我国农业县(市)发展绿色食品普遍存在的问题,在此基础上提出了发展绿色食品的对策。  相似文献   
92.
长江流域商品粮基地建设与农业持续发展   总被引:6,自引:4,他引:2  
长江流域横跨我国中亚热带,光、热、水气候资源及其时空组合优势明显,土地自然生产力较高。粮食生产在全国占有重要地位。但由于流域内山地比重大,人口稠密,人均土地资源偏少,在现有耕地资源有限和粮食市场不稳等的多重压力下,历史时期内形成的“南粮北调”正逐渐被“北粮南调”所取代。在分析长江流域粮食生产现状和近二十年来商品粮基地建设对粮食生产的促进作用的基础上,从流域经济持续发展角度,提出了发挥长江流域粮食生  相似文献   
93.
三峡库区山地可持续农业发展的问题与对策   总被引:1,自引:0,他引:1  
三峡库区山地农业的发展与三峡工程的命运休戚相关。本文在详细分析库区山地可持续农业发展的主要制约因素的基础上,提出了库区山地可持续农业发展的主要途径  相似文献   
94.
该文就常熟市农业资源的实际出发,从改造中低产田、开发长江滩地、复耕零星废弃地、利用庭园空间、立体利用水面、开发杂草资源、加工植物蛋白饲料及发展棉田套作等8个方面的途径,评价了农业开发潜力,说明在经济发达地区的农业开发是大有可为的。文章提出了相应的实施对策。  相似文献   
95.
The following paper examines the main factors determining long-run agricultural land expansion in Latin America compared to other tropical regions. Given the importance of natural resource-based sectors for most economies in Latin America, the impact of price-induced "resource booms" on economic growth in the region is explored. In addition, the paper examines whether there is an inherent "boom and bust" pattern of economic development associated with agricultural land expansion in Latin America, and the extent to which economic policies in the region exacerbate this problem. The paper concludes by examining the role of targeted policies in alleviating the structural obstacles to Latin American agricultural and economic development.  相似文献   
96.
我国农业自然灾害与农业政策性保险   总被引:6,自引:0,他引:6  
刘荣茂  邱敏 《灾害学》2007,22(3):109-113,138
在详细分析了我国当前主要农业自然灾害情况的基础上,探讨了通过建立农业政策性保险来应对自然灾害风险的必要性以及我国农业保险目前面临的问题,提出了加大政府支持力度、加快农业保险立法、提高保险意识、加强保险人才培养等方面的政策建议。  相似文献   
97.
ABSTRACT: A partial production function for corn that considers the time and amount of water applications is determined. Examples are worked out by using data on site specific parameters for nine soil sites in the Great Plains Region repesenting various combinations of water holding capacity, pan evaporation, and average rainfall. It is found that soils with a low water holding capacity are more water and energy intensive in crop production and thus more vulnerable to fluctuations in net returns due to declining water tables or energy shortages. Despite this, farmers of low water holding capacity soils are likely to opt for irrigation. This points to the existence of a necessary, but sufficient, condition for socially inefficient use of ground water resources. This calls to question the property right concept in water created through the appropriation doctrine and the “law of capture.” This paper indicates the type of analysis that must be undertaken in order to make appropriate changes in laws governing water use.  相似文献   
98.
ABSTRACT: This paper discusses the consumptive water needs of the various energy conversion processes including oil shale retorting, coal gasification and liquefaction, electric power generation, and slurry pipelines. Projected energy development water needs in the upper Colorado River and Upper Missouri River basins are compared with projected agricultural needs and water available. The comparative cost and values of water to energy and agricultural development are discussed to emphasize this as well as the political and social factors entering into the picture.  相似文献   
99.
ABSTRACT: Faced with the necessity of meeting growing municipal water requirements in areas where available supplies are completely allocated, numerous cities throughout the West are turning to their eminent domain powers to affect a reallocation of water from less preferred uses to municipal uses, thus bringing about a sharp conflict with agricultural interests. As a basis for discussing these eminent domain powers, this paper begins with a brief review of the development of property rights. The existence of both private and public (social) rights in the “bundle of rights” is noted. In recent years the Public Trust Doctrine has been used to limit private rights in property, and to protect and strengthen social rights. A case study which focuses on a conflict between individual and social interests in water rights is discussed. This case involves the City of Thorton, Colorado which initiated municipal condemnation proceedings to acquire the water rights and structures of two nearby irrigation companies. The case represents an attempt to incorporate the spirit of the Public Trust Doctrine into legislation which sets forth procedures for resolution of similar water rights conflicts that will inevitably become more numerous throughout the West in the future.  相似文献   
100.
ABSTRACT: Rapid population growth in the metropolitan area of Denver, Colorado, is causing conflicts over water use. Two cities, Thomton and Westminster, have begun condemnation proceedings against three irrigation companies to secure agricultural water rights for municipal use. This is the first condemnation proceeding against irrigation water rights for municipal use. Should the suit succeed, over 30,000 acres of presently irrigated land will lose its water supply. There are about four hundred landowners in the area; two hundred of these are commercial farmers, including truck, dairy and specialty farms. Total agricultural production amounts to about $8 million per year. About 561 jobs related to agriculture will disappear along with about $4 million in not income. Only 6.4 percent of the farmland along the Front Range is irrigated. Continued urban growth will put pressure on the water supply of much of this land. The interested parties of the region should cooperate to lessen the impact of urban growth on agricultural lands and water by forming a metropolitan water district. Such a district could share costs of development of additional municipal water and develop systems where municipalities would recycle waste water back to the irrigated lands.  相似文献   
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