强化处置闲置地

闲置地是当前土地资源利用和管理中值得关注的重要问题。闲置地弊端甚多，严重地威胁了子孙后代的生存和社会经济的可持续发展。闲置地本质上是二元土地制度的产物，也是投机因素作祟的结果。强化闲置地的处置须从改革土地制度、规范地方政府行为、无偿收回闲置地、健全政策法规等多方面努力。     

辽宁省节水型社会建设的发展与思考

辽宁省人均水资源占有量远低于全国和世界平均水平,是水资源严重缺乏的省份。为了保证经济社会发展的用水需求,辽宁省在开发水资源的同时,逐步加大了节水力度,相继建立了各级节水机构,开展节水宣传,逐渐提高人们的节水意识,制定实施了计量收费、计划管理、超计划加价收费等节水政策措施,初步实现了用水定额管理,启动了节水型社会建设试点。     

宜兴抽水蓄能电站环保及水土保持工程的综合利用

介绍了宜兴抽水蓄能电站建设过程中对环保及水土保持工程综合利用的做法.项目利用实施4#拦渣坝环保及水土保持工程,根据所处区域的地形、地貌,通过对4#拦渣坝的设计优化,不但使其具有拦挡冲沟的泥沙进入下水库的功能,又利用改进坝型形成一定供水能力的小水库解决了可以提供符合标准的生活用水的难题,从而提升了4#拦渣坝的复合功能,实现了该电站环保及水土保持工程的综合利用.     

Triple jump about urban land potential release in China

Recent two decades, the great changes take place in China, especially in land use area. After the marketization, the urban land potential of China releases gradually. Three models in this paper show the three stages of reforming land use system. This paper will give a clear picture of urban land use in China that spans nearly thirty years.     

Stop and Go Agricultural Policies with a Land Market

This article studies the design of farm policy in the presence of asymmetric information about farmers' productivity, a government objective to insure farmers a minimum "parity" income, an endogenous land rent, and diminishing returns on alternative (nonprogram crop) land uses. In this setting, acreage set asides are never part of an optimal farm policy, although compensated acreage limits are. When there are new farmer entrants who cannot be excluded from farm programs, optimal policy takes the form of a pure voluntary acreage limitation—or "buyout"—program in which high-cost producers participate and low-cost producers do not.     

Land tenure and rental in Western Sudan

This paper reports on aspects of land tenure in western Sudan, especially the nature of tenure insecurity and the functioning of the land rental market. The active land rental market accounted for about one-third of cultivated land. Patterns of land rental transactions, and tests of the importance of insecurity in renting land, where the owner may not be able to reclaim land rented out, do not support the presumption that rental markets perform poorly. The role of the sheikh as administrator of village land, and the claims of large landowners to vast tracts, are, however, important political problems that must be resolved before attempts at ‘rationalizing’ land tenure.     

农村经济的“第二个飞跃”与农用土地制度改革

土地制度的安排与改革决定着农村经济发展的前程。我国农业的改革和发展,要有两个飞跃:第一个是实行以家庭联产承包经营为主的责任制;第二个是发展适度的规模经营,发展合作经济。现行土地制度制约着第二个飞跃的实现,需要调整和完善。土地私有化不是我国土地制度改革的方向。土地制度改革在于适应现代农业建设的需要,构建农地财产权新的框架,以利于农业产业化经营,发展多种形式的适度规模经营。     

构建农村和谐社会的思考

构建农村和谐社会,应当树立正确的农民增收观,促进农民持续快速增收,缩小城乡差别;加快农地产权制度改革,解决农地矛盾和纠纷;加快农村基层组织制度和县乡行政改革,解决农村干群矛盾;加快农村教育发展,改进农村教育质量,提高农民素质;加大再造秀美山川工程监管力度,消除工作中存在的不实、不公等因素;加快农村社会保障制度建设,消除农民的后顾之忧.     

Developing habitat associations for fishes in Lake Winnipeg by linking large scale bathymetric and substrate data with fish telemetry detections

Understanding relationships between freshwater fishes and habitat is critical for effective fisheries and habitat management. Habitat suitability indices (HSI) are commonly used to describe fish–habitat associations in rivers and other freshwater ecosystems. When applied to large lakes however, standard sampling procedures are inadequate because of larger sampling areas and an increased risk of fish collection bias through one-time observations. Here, we use lake bathymetry, substrate, and multiple fish telemetry detections collected from a systematically deployed receiver grid to develop HSI for four fish species (lake sturgeon, freshwater drum, common carp, and walleye) in Lake Winnipeg. Seasonal variations in habitat use based on water depth and substrate were observed in three of four species. Lake sturgeon remained in shallow locations with predominantly gravel substrate near the mouth of the Winnipeg River regardless of season. Freshwater drum persisted over fine substrate in both summer and winter but had a broader depth range in the summer compared to winter. Common carp shifted from mid-range depths and silt substrate in the summer to shallow depths and gravel substrate in the winter. Walleye showed an unchanging association to fine substrate but expanded from primarily mid-range depths in the summer to include shallower depths in the winter. These findings show how multiple telemetry detections per fish can be combined with hydroacoustic data to provide informative habitat associations for fishes in a large lacustrine ecosystem.