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基于~(137)Cs技术的中国北方农牧交错带土壤侵蚀研究
作者: 姜洪涛   来源: 内蒙古师范大学 年份: 2010 文献类型 : 学位论文 关键词: 土壤侵蚀   农牧交错带   ~Cs   示踪  
描述: ttention, but also agriculture and eco-environmental sustainable development important problems. Farming-pastoral Transitional zone in north China, as our county returning farmland to forest and returning cropping land to grassland are the focus areas, natural environment and socio-economic conditions shown a clear transition characterized by the transition zone of the interpenetration and staggered distribution of agriculture and animal husbandry, which is curbing desertification important ecological barrier, but also ecologically fragile belts.
全文:、平耕地、坡灌丛地、退坡耕地、果耕间作地、坡林地、坡耕地、坡草地;大同各种土地利用类型中~(137)Cs含量从高到低的顺序为:平草地、坡草地、平林地、坡耕地、平耕地、坡灌丛地。 依据背景值确定原则
西北旱作农区农作制优先序研究
作者: 成敏   来源: 西北农林科技大学 年份: 2010 文献类型 : 学位论文 关键词: 西北旱作农区   BP神经网络   农作制优先序   抗旱减灾对策?  
描述: est region, which c ombined with the water-saving, agricultural soil and water conservation techniques, and then taken " drought resistance, reduce erosion, increase efficiency" as a principle.
全文:了以资源节约高效利用、抗旱减灾为主的农作制以及合理有效的抗旱减灾对策。主要得出以下结论: (1)通过在甘肃天水、定西、平凉、庆阳地区,宁夏银南地区、固原地区,陕西宝鸡、咸阳、渭南、铜川、延安、榆林地
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