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781.
中国水资源管理问题及对策   总被引:19,自引:0,他引:19  
水资源管理是当今大多数国家资源管理的难题。中国由于其自身的具体国情,在水资源管理上又有新的管理困境。本文对这一困境进行剖析并提出解决问题的对策。  相似文献   
782.
Chemical properties and pollution of water resources were studied in the Hunchun basin, which is located in northeast China and borders directly North Korea and Russia along the Tumen river. Water quality was characterised according to its major constituents and geological features. Ground waters could generally be grouped into (Ca+Mg)-HCO3 type and (Ca+Mg)-(SO3+Cl) type in first and the second terrace areas, respectively. The mixing of these two types depends on the local conditions, such as pumping or permeability variations.Hunchun city is a pollution source for local water resources due to its uncontrolled sewage and urban discharge. In a previous study of the southwestern part of the Hunchun basin, groundwater contamination by Fe, Mn and NO3-N was reported. In addition, this study identified Cd and F as prevailing contaminants in the water resources. Pollution of water resources by these contaminants appeared to be affected by the application of fertilisers, irrigation practice, variation of aquifer characteristics, solubility of mineral phases, and discharge of domestic sewage. Wide distribution and high levels of Cd and F in surface- and ground waters could pose significant problems if they are utilised as major water supply sources.  相似文献   
783.
位于云南省西北哈巴雪山中的三坝纳西族自治乡,由于历史原因,其人口组成中的汉族和纳西族分别聚居于境内的格基河和白水河2条小流域,从而形成了各有特点的景观利用格局. 应用景观生态学和文化人类学的研究方法,对三坝纳西族自治乡内2条小流域的景观格局进行了研究和分析. 结果表明:白水河流域的景观优势度比格基河流域高,且差异显著;白水河流域的景观破碎度比格基河流域高;白水河流域的景观多样性比格基河流域低,但差异不显著. 同时对其民族分布及其耕作文化的调查显示,纳西族的神山崇拜、聚居和梯田耕作文化对其居住的白水河流域景观格局的形成有直接联系.   相似文献   
784.
年楚河流域是西藏发达的农业区,有"西藏粮仓"之称,对区域经济发展起着决定性的作用.然而对该流域水体水化学的系统研究鲜见报道.为揭示年楚河流域水化学特征及其控制因素,本研究于2018年11月(平水期)对年楚河主干流及其主要支流的水体理化参数、主要离子和微量元素进行分析研究.结果表明,年楚河流域水体总体呈弱碱性,总溶解性固...  相似文献   
785.
洮儿河流域农业生态地质环境研究   总被引:1,自引:0,他引:1  
系统分析了吉林西部洮儿河流域的农业生态地质环境特征,揭示了流域内影响农业可持续发展的五大农业生态地质环境问题;按照地质、地貌、自然资源状况、生态环境灾害、环境质量等综合要素对流域进行了环境分区;最后论述了流域内农业生态地质环境的演化过程和影响因素。  相似文献   
786.
皇甫川丘陵沟壑区小流域生态用水实验研究   总被引:15,自引:1,他引:14  
一个强烈水土流失小流域(准格尔五分地沟),经过20多年水土保持植被建设,乔灌草人工植被镶嵌分布,覆盖率达80%,在有效遏制水土流失的同时,也消耗相当量的水资源---生态用水。2002年生长季节,采用实验研究方法,测定了该小流域各不同类型植被蒸散量、各不同类型土壤贮水量及降水量等,计算出该小流域四大类型植被生态用水(按大小顺序):①农田为5321.3m3/hm2;②乔木林为4654.8m3/hm2;③灌木林为4047.8m3/hm2;④草原为3244.3m3/hm2。估算出全小流域生态用水量:①各类植被生态用水量约150×104m3;②水库湿地生态用水量约26×104m3;③居民点生态用水量约4000m3。三项合计,即五分地沟小流域总生态用水量约176×104m3。值得重视的问题是:该小流域植被生态用水量和总生态用水量均超出同期降水量(130×104m3)达20×104~40×104m3。这意味着土壤贮水量耗减20~30mm。因此,在生态环境建设中,构建适宜的植被模式,调控生态用水量,将对维持生态系统稳定及其环境改善起重要作用。  相似文献   
787.
Increasing water scarcity is increasing pressure on water management institutions, particularly in the area of water rights. A common response is to formalise water tenure, one of several options for securing access and resolving conflicts concerning water allocation. This article looks at four contexts where negotiation, self-governance and concepts of legal pluralism may help improve water resource management. Existing users and potential new users need to negotiate before water resources are developed. Users can participate in forums with authority to solve basin management problems through self-governance. Negotiated water transfers offer an alternative to water acquisition by expropriation.  相似文献   
788.
This paper identifies a line of reasoning based on a number of concepts and tools to facilitate river basin management, which have been applied in a case study. For long-term sustainable river basin management, a balance is needed between the human use of the river and its basin, the ecological functioning of the river and receiving waters, and the river's capacity to supply goods and services. To find such a balance a framework is needed that illustrates and clarifies possible trade-offs between economic use and environmental supply by integrating scientific information on cause–effect chains on a catchment scale. A number of concepts and tools are proposed as a basis for this framework. The tools are: (1) indicators that describe the complex interactions and processes in rivers; (2) a suite of linked models that predict the economic, environmental and ecological effect of management measures; (3) an evaluation framework to rank different management alternatives on the basis of three objectives: economic efficiency, spatial equity in costs and benefits and environmental quality of the river and receiving lakes. The concept of environmental quality defines the potential of the river environment (i.e. natural capital) to contribute to human welfare. The concept of environmental functions is used to identify societal interest in natural capital. The concept and tools have been applied in a case study involving the evaluation of four management strategies on nutrient abatement in the Rhine basin. The result of the case study is that economic efficiency is in conflict with spatial equity and environmental quality. Spatial equity is in agreement with environmental quality. Electronic Publication  相似文献   
789.
ABSTRACT: The model bankfull discharge recurrence interval (annual series) (Ta) in streams has been approximated at a 1.5‐year flow event. This study tests the linkage between regional factors (climate, physiography, and ecoregion) and the frequency of bank‐full discharge events in the Pacific Northwest (PNW). Patterns of Ta were found to be significant when stratified by EPA Ecoregion. The mean value for Ta in the PNW is 1.4 years; however, when the data is stratified by ecoregion, the humid areas of western Oregon and Washington have a mean value of 1.2 years, while the dryer areas of Idaho and eastern Oregon and Washington have a mean value of 1.4 to 1.5 years. Among the four factors evaluated, vegetation association and average annual precipitation are the primary factors related to channel form and Ta. Based on the results of the Ta analyses, regional hydraulic geometry relationships of streams were developed for the PNW, which relate variables, such as bank‐full cross‐sectional area, width, depth, and velocity, to bankfull discharge and drainage area. The verification of Ta values, combined with the development of regional hydraulic geometry relationships, provides geographically relevant information that will result in more accurate estimates of hydraulic geometry variables in the PNW.  相似文献   
790.
煤层瓦斯形成的构造地质条件及瓦斯灾害预防   总被引:8,自引:1,他引:7  
煤盆地的地质构造条件是研究煤层瓦斯形成、富集区分布规律的重要因素。通过对我国含煤盆地的地球动力学背景分析,及储层、盖层中构造裂隙对煤层瓦斯控制因素的研究,阐明了中国大陆是一个由若干陆块和褶皱带组成的复合大陆,煤盆地构造稳定性差,煤层瓦斯赋存条件复杂,这是造成煤层瓦斯突发的根本原因;我国煤盆地大都经历了印支、燕山和喜马拉雅运动,煤盆地受到不同程度的改造,影响了煤层瓦斯的保存条件;弱改造型煤盆地的瓦斯含量较高;强改造型煤盆地瓦斯含量较低。同时指出,面对煤矿瓦斯灾害事故的频繁发生,必须加强对瓦斯事故发生机理等重大理论问题的研究,加强生产、技术人才的培养,坚持“先采气,后开矿”的原则。  相似文献   
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