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机构地区:[1]中国科学院兰州沙漠研究所 [2]北京印刷学院
出 处:《中国沙漠》1993年第2期19-28,共10页Journal of Desert Research
摘 要:本文通过分析东庄营村农业系统的现状,根据系统结构决定系统功能的原则,利用生态经济平衡的原理,寻求农业系统最佳结构模式,以求土地资源利用充分、合理,农业系统结构趋于合理,系统功能改善,生态经济效益显著提高。In this paper, a linear planning model tor me agroeeosyscem in Dongzhuangying village was de gned and calculated. In the model, land resources are used fully and reasonably, the structure of the system tends to be reasonable , tne function of the system is improved and the ecu-economlc bene of the system increases markedly. Ratios of the production values of agriculture to forestry to hus-pandry are regulated from 1 : 0. 06 : 0. 25 in 1989 to 1 : 0. 72 : 0. 85 in the first phase (1995) and 1: 1. 65 : 0. 97 in the second phase(2000). The production values of the system in 1995 and in 2000 will be 2. 86 and 4. 58 times those in 1989. The coverage of forest is raised from 24. 77% in 1989 to 31. 86% in 1995 and 35. 00% in 2000. The nitrogen content in soil tending to baiance. The ratio of straw returning to farmland increased by 0% in 1989 to 45-50% in 1995 and 55-60% in 2000.
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