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981.
加入WTO后关于我国土地资源可持续利用与管理的思考   总被引:1,自引:0,他引:1  
文章首先简要介绍了加入WTO给我国带来的发展机遇,分析了加入WTO对我国农用地的数量,质量、经营规模和粮食自给率的影响,并就加入WTO对国有企业的用地效益,房地产业与土地市场的冲击以及未利用土地的影响进行了探讨。最后,提出了适应WTO我国土地资源可持续利用与管理的对策。  相似文献   
982.
Traditional environmental knowledge (usually imparted orally) is being lost from many regions of the world, requiring novel forms of transmission if this situation is to be redressed. Loss of this knowledge may be a significant contributory factor towards ecological decline. Undoubtedly, disruption to ecosystems and societies that depend on these has impacted on traditional land management practices, with negative ramifications for biodiversity. From an environmental perspective, scientists in northern Australia need to understand traditional Aboriginal methods of ‘caring for country’, such as burning regimes, so that these can be incorporated into strategies today for maintaining Australia’s rich biodiversity. However, information exchange should be two-way: as well as learning from local people, science can in turn benefit people who may have little experience of, for example, invasive species. The challenge is how can the complexity of biological knowledge from within different ontologies be represented and integrated in a way that it can be of use to scientists and local people, in order to ensure a sustainable future? The main aim of this study was to record existing local knowledge of biodiversity for the community of Aurukun (far north Queensland), integrating this knowledge with scientific data, while giving parity to both knowledge systems and protecting intellectual property rights. A cross-cultural collaboration between community members and ethnobiologists resulted in development of the Aurukun Ethnobiology Database. An interdisciplinary approach was taken to effectively model autochthonous biological knowledge and scientific data to create a database with a number of practical applications.  相似文献   
983.
荒漠交错带开发利用研究——以新疆于田绿洲为例   总被引:3,自引:0,他引:3  
绿州—荒漠交错带是一个生态环境脆弱带 ,由于其自然系统发育的先天不足 ,加上人类的开发活动 ,经济发展与生态环境保护矛盾进一步加剧 ,已成为影响绿洲发展的一个重要方面。本文以于田绿洲为例 ,通过分析于田绿洲荒漠交错带的开发利用现状 ,提出相应的交错带生态环境建设的建议和保护措施。  相似文献   
984.
ABSTRACT: A study was undertaken to determine the effect of water intensive appliances or activities on household water consumption. Activities included in the study were use of the washing machine, dishwasher, swimming pool, and lawn watering. In the majority of cases these activities increased per capita consumption and were statistically significant. Households included in the study were not familiar with water saving devices available in the retail market. Even if tehse appliances were purchased, private economic benefits to the household would be low due to the inexpensive water charges levied. However, aggregate community benefits could be large if new well drilling cost or increase in storage facilities could be avoided. In order to avoid these increased costs, regulation or subsidy programs may be the most efficient policy alternatives available to the communities. Subsidies and regulation could potentially decrease water use and offer alternatives to increasing the water supply.  相似文献   
985.
本文以江苏省江阴市为例 ,采用定性分析与定量诊断相结合的方法 ,研究了经济发达地区土地资源可持续利用水平、动态变化以及障碍因素。研究表明 :江阴市土地资源利用已进入基本可持续状态 ,但也出现了生态环境恶化、建设用地比重增大、耕地面积下降等问题。针对诊断结果 ,提出了促进土地资源可持续利用的几项对策  相似文献   
986.
ABSTRACT: Nebraska statutes give first preference for use of ground water to domestic purposes, second to agriculture, and third to manufacturing or industrial purposes. Rapid growth in the number of irrigation wells has caused an increasing number of water use conflicts. One such conflict arose from the installation and use of an irrigation well near Madison in Madison County, Nebraska. Pumping from the irrigation well coincided with head declines in nearby domestic wells screened in the same sand and gravel, but appeared unrelated to water level changes in wells screened in a higher saturated sand. A drawdown-recovery test was performed to determine the degree of hydraulic connection between the wells involved. Operation of the irrigation well was determined to be the cause of the head decline in nearby domestic wells screened in the same sand and gravel. Partly as a result of this conflict, legislation recently introduced into the state legislature would require that wells of higher preference be “reasonably” constructed if wells of lower preference are to be held liable for head loss.  相似文献   
987.
城市总体规划环境影响评价方法   总被引:4,自引:0,他引:4  
开发不同类型规划的环境影响评价技术和方法是当前国内的热点研究领域之一.围绕城市总体规划特点,在分析识别规划经济增长和用地布局方案中存在的多种不确定性的基础上,以产业和用地为基本评估单元,综合运用蒙特卡罗随机采样技术和HSY算法,并将其与地理信息系统进行整合,建立了基于结构与空间不确定性分析的城市规划环评方法和系统评估模型.  相似文献   
988.
根据对云南香格里拉县生态旅游环境友好型土地利用模式的野外调查和研究工作,分析出现象背后的模式内涵,总结形成该模式的地域特点,并指出此种土地利用模式解决的人地矛盾,为其它地区借鉴此种环境友好型土地利用模式提供实例参考,最后建设性地提出了推广此种模式应具备的条件,为具体实施提供理论指导。  相似文献   
989.
Uncertainties hamper the implementation of strategic environmental assessment (SEA). In order to quantitatively characterize the uncertainties of environmental impacts, this paper develops an integrated methodology through uncertainty analysis on land use change, which combines the scenario analysis approach, stochastic simulation technique, and statistics. Dalian city in China was taken as a case study in the present work. The results predict that the Fuzhou River poses the highest environmental pollution risk with a probability of 89.63% for COD in 2020. Furthermore, the Biliu River, Fuzhou River, Zhuang River, and Dasha River have 100% probabilities for NH3-N. NH3-N is a more critical pollutant than COD for all rivers. For COD, industry is the critical pollution source for all rivers except the Zhuang River. For NH3-N, agriculture is the critical pollution source for the Biliu River, Yingna River, and Dasha River, sewage for the Fuzhou River and Zhuang River, and industry for the Dengsha River. This methodology can provide useful information, such as environmental risk, environmental pressure, and extremely environmental impact, especially under considerations of uncertainties. It can also help to ascertain the significance of each pollution source and its priority for control in urban planning.  相似文献   
990.
中国农业用水与经济增长的Kuznets假说及验证   总被引:5,自引:0,他引:5  
提出中国农业用水与经济增长的Kuznets假说,并对此进行了分析和验证。在对改革开放以来中国经济增长与农业用水的趋势进行直观分析后,采用了中国31个省市区1999~2005年人均农业用水量和经济增长相关指标的面板数据,通过计量模型检验农业用水库兹涅茨曲线在中国是否存在,定量分析了农业用水量变动与经济增长之间的规律。研究结果表明:农业用水量最初随着人均GDP和人均农林牧渔业增加值增长而增加,当达到某一个阈值点后,开始逐渐下降,基本上符合库兹涅茨曲线的特征。中国目前已处于农业用水库兹涅茨曲线的右半段,但农业用水量下降的速度较为缓慢。因此,在促进经济增长的同时,要注重利用管理和技术等手段来发展节水农业,这将有助于在农业产业内部提升用水效率,缩减农业用水量。〖  相似文献   
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