按文献类别分组
关键词
甘肃省黄河沿岸地区水资源承载能力分析
作者: 刘建兰   来源: 兰州大学 年份: 2010 文献类型 : 学位论文 关键词: 甘肃省   沿黄地区   水资源   承载能力   系统动力学  
描述: th, the demand of water resource is continuously increasing. That is to say water shortage has become a global problem. Water resources carrying capacity is the basis and prerequisite of regional socio-economic development, which is significant to realize the coordinated development of regional "water resources- ecological environment-socio-economy" composite system. So it has become the focus and hot topic in water science field nowdays.
全文:水资源是人类生存和社会发展最重要的基础资源,随着世界各国经济和人口的增长,水资源的需求量不断增加,水资源短缺已经成为全球性问题。水资源承载能力对于实现区域“水资源一生态环境一社会经济”复合系统
甘肃省黄河沿岸地区水资源承载能力分析
作者: 刘建兰   来源: 兰州大学 年份: 2010 文献类型 : 学位论文 关键词: 甘肃省   沿黄地区   水资源   承载能力   系统动力学  
描述: th, the demand of water resource is continuously increasing. That is to say water shortage has become a global problem. Water resources carrying capacity is the basis and prerequisite of regional socio-economic development, which is significant to realize the coordinated development of regional "water resources- ecological environment-socio-economy" composite system. So it has become the focus and hot topic in water science field nowdays.
全文:水资源是人类生存和社会发展最重要的基础资源,随着世界各国经济和人口的增长,水资源的需求量不断增加,水资源短缺已经成为全球性问题。水资源承载能力对于实现区域“水资源一生态环境一社会经济”复合系统
西部干旱地区农户旱地种植行为实证研究
作者: 叶晶晶   来源: 南京农业大学 年份: 2010 文献类型 : 学位论文 关键词: 农户   旱地   水资源   决策   干旱风险  
描述: ncentrated v}}ith 85% of the total dry lands. and it is important for the national economy and the countr<0's strategic agricultural growth. Northwest arid areas basically depend on natural precipitation. water shortage has seriously affected the farmers practices. The decision of farmers to plant dry land is a two-stage decision-making behavior: They first have to decide whether to plant dry land, and then decide what kind of crops planted in the dry lands. It is essential to find effective ways to raise the enthusiasm of farmers planting and reasonable arrangements for dry land crop structure. However. ver}} few people study dry land farming practice from the perspective of water shortages.
全文:作物结构是十分必要的,但是很少有人从水资源短缺的角度对农户的旱地种植行为进行研究。 基于以上背景,本文选择了水资源短缺比较明显的甘肃省张掖市民乐县为研究区域。文章通过干旱条件下分析影响农户种植决策
气候变暖趋势下甘肃省粮食供需问题研究
作者: 王海强   来源: 甘肃农业大学 年份: 2010 文献类型 : 学位论文 关键词: 甘肃省   粮食供需   气候变暖  
描述: Climate change have been one of the most important factors that influence the global development.
全文:气候变化已经成为影响全球发展的重要因素之一。世界政府间气候变化委员会发布的《气候变化综合报告2007》中指出气候变化将对经济、社会产生重大影响,中纬度地区的农业生产将面临较为严峻的水资源匮乏等困难
秦汉时期中原地区环境的变迁与农耕技术的选择
作者: 王大宾   来源: 郑州大学 年份: 2010 文献类型 : 学位论文 关键词: 环境变迁   农耕技术选择   中原   秦汉  
描述: 环境对农耕区域及其技术的形成有明显影响。除去社会生产关系因素,制约农耕技术的环境因素大体有气候、水资源、土地和土壤、植被以及人口环境,耕作技术处于多种环境因素的中心。中原地区的农业技术代表传统农业的技术发展水平,秦汉时期中原地区的技术水平及其发展程度是我们认识其分布规律的基础。这一基础形成于先秦时期
全文:环境对农耕区域及其技术的形成有明显影响。除去社会生产关系因素,制约农耕技术的环境因素大体有气候、水资源、土地和土壤、植被以及人口环境,耕作技术处于多种环境因素的中心。中原地区的农业技术代表传统农业
文明传播视野下的汉代河西开发
作者: 刘俊玲   来源: 青海师范大学 年份: 2010 文献类型 : 学位论文 关键词: 河西   汉代   开发   文明  
描述: ral environments make the cultural dissemination possible. In archeological materials we can see plenty of Neolithic culture and Bronze culture,which may be nomads. Ywati, Wusun, Hun were lived here.Befor Han Dynastie ,the area was regarded as wild and woolly place.the Hun sprang up during Qin and Han Dynastie, Gansu Corridor became more and more imporant in military and politics affairs. After the establish of Western Han Dynasty ,the imperium rehabilitated for tens of years . Emperor han wudi change the plant to the Hun. I n the second year of yuanshou of Emperor han wudi(121BC),Huoqubing go on an expedition to Gansu Corridor,and wan,because the Hunye king killed the Xiutu king . The Hunye king surrenderred and leaded his man about 40000 .This is significant to the history of culture diaaemination. From then on,Han culture hold the dominant position in the war.The pattern of dissemination were war,politics and valueas.And the policy which Han made decision of the dissemination and the speed. After long time Interaction,the two change the hisroy of this area.Although some rejection and degradation happened,the new trail was certainty. Agricultural civilization took new tools to the area,and finally the Silk Road was freely.It made a contribution to culture dissemination.However,the aggressive e x p a n s i o n m a d e t h e immigrate and armies too huge,and led the crisis of ecologyand resource. Qiang civilians uprising during the Eastern Han Dynastie made the land desertificated. The process was not at one stroke,but a long time. Rely on force was to set up a unified ,multinational country.
全文:原本并不丰富的地区,水资源、森林、草原资源被人为的破坏,河西开始荒漠化。到东汉后期,羌民起义,农耕民族有退出河西之举,抛弃屯田,这样荒漠化进一步推进,为河西的生态发展带来隐患。 文明的传播不是一蹴而就
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:本文针对西北地区降水资源短缺、旱灾频发、土壤侵蚀严重和农村经济贫穷落后的现状,结合已有的旱作节水、农田水土保持等单项技术,以“抗旱、减灾、增效”为原则,通过实地调研,并结合已有技术成果的分析、农户
< 1
Rss订阅