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浏览/检索结果: 共5条，第1-5条 帮助 限定条件 内容类型：会议论文     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Mode Choice of Residents in Large-Scale Residential Areas in the Periphery of Shanghai: A Case Study of Jinhexincheng, Jiading District 会议论文 The 16th COTA International Conference of Transportation Professionals (CICTP2016), 上海，中国 作者:  Xin Zhang;  Jinping Guan 收藏  |  浏览/下载：15/0  |  提交时间：2017/01/15 Efficiency and Economy of a New Agricultural Rainwater Harvesting System 会议论文 Wen-Hua J.; Jian-Ming C.; Van Veenhuizen M. 收藏  |  浏览/下载：11/0  |  提交时间：2012/06/30 Beijing  greenhouse agriculture  rainwater harvesting  cost-benefit   Land use dynamics and landscape change pattern in Hetao irrigation district, Inner Mongolia, China 会议论文 6th International Symposium on Digital Earth: Data Processing and Applications, Beijing, China, September 9, 2009 - September 12,2009 Zhang, Yinhui; Luo, Yi; Zhao, Wenwu 收藏  |  浏览/下载：16/0  |  提交时间：2014/12/07 This study analyzed spatial and temporal changes in land use in an irrigation district covering an area of 1.7 million ha in Northern China by GIS analyses and also investigated changes in landscape pattern using the landscape structure analysis program FRAGSTATS over the study period from 1986 to 2000. The decreases in farmland and the increases in grassland area mainly resulted from the policy of grain for green and converting slope farmland into pasture from China government. In spite of the efforts to conserve the fragile ecosystem  the land degradation  including soil salinization and grassland degradation  was spreading rapidly. The area of alkali-saline land increased by 22493 ha and about 50555 ha of dense grassland degraded into mid-density grassland. In terms of landscape fragmentation  both farmland and dense grassland showed the tendency of increased fragmentation. Both adverse natural conditions and human activities are responsible for the land degradation expansion in Hetao irrigation district  but the root causes are increasing population pressure and irrational human activities  such as flooding irrigation method and over-grazing. To prevent land degradation from spreading  population control and improvement of the management are prerequisite approaches. 2010 SPIE.   A contrast experiment based on the modification theory of toroidal worm 会议论文 2011 International Conference on Material Science and Information Technology, MSIT2011, Singapore, Singapore, 2011 作者:  Wen, Qingming;  Xu, Hua;  Tang, Weixiang 收藏  |  浏览/下载：0/0  |  提交时间：2020/01/05 Study on the outsourcing management of e-government in China 会议论文 3rd International Conference on Theory and Practice of Electronic Governance, ICEGOV 2009, Bogota, Colombia, 2009 作者:  Yuanfu, Jiang;  Jiazhen, Liu;  Peng, Du;  Tan, Yu 收藏  |  浏览/下载：2/0  |  提交时间：2020/01/13