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1.
With the development of science and technology, the researches and application of water resources including the gas water have been constantly developed. Through an analysis on the flaws of the water right theory, and by executing reconstruction and renewal of the theory and system of water right in modem society, the water right position of the gas water will be established, leading to the maturity of the whole law effectiveness and substantial results of water right.  相似文献   

2.
The natural supply of land resources is limited, but the economic supply may change along with social and economic development, and its size is decided bye nature and social and economic body conditions. When the supplying ability of land resources threatens the development of society and the conflict between people and land becomes tense, it forced people to im- prove land utilization and to increase the effective supply of land resources. The paper made an overall consideration on the characteristics of the irrigated farming and the frail ecological environment in Fuhai County, Altay Area, Xinjiang Uigur Autonomous Region and explored land arrangement planning as well as water resource planning and environmental protection. The paper evaluated natural resources, land utilization and water resource of the case study areas and focused on the spatio-temporal balance between the utilization of water and land resources. In the end the paper a feasible plan was made out for the land arrangement project.  相似文献   

3.
We are accustomed to solve the problem of the water scarcity in the western region by the thought of increasing the effective supply of water to meet the needs of Go-west Campaign. After introducing the dynamic equilibrium principle on supply and demand in economy, we find that we should solve the problem of the water scarcity in the western region through reducing total demand to achieve the dynamic equilibrium of supply and demand. Finally water resources in the western region can be enlarged by an accumulated way.  相似文献   

4.
Analysis of China‘s Water Security and Virtual Water Trade   总被引:1,自引:0,他引:1  
Producing goods and services all needs water consumption. The water used in the process of an agricultural or industrial product is called the “Virtual Water“ contained in this product.Through international trade, water-scarce countries and regions could purchase water-intensive products--especially foods, from water-rich countries to balance their water deficits and achieve water safety. China is one of the 13 most water-deficit countries whose water safety have been severely challenged. This paper generalized the recent global research development and made a brief introduction about the methods calculating virtual water content in specific products. As a case study, we qualified China‘s annual virtual water flows from year 2000 to 2002 with trade in crops, and ended with some policy advice for application and practice of virtual water strategy.  相似文献   

5.
Since the 1990s, the Yellow River stream has been temporarily interrupted for several years, which affects the development of society, the economy and human life, limits the economic potential of the drainage areas, and especially causes great harm to regions on the lower reaches. Based on the analysis of the relationship between the development of society and economy and water scarcity, the author thinks it is necessary to optimize and adjust the industrial structure that has extravagantly consumed enormous amounts of water, and to develop ecological agriculture, industry and tourism which are balanced with the ecological environment. Finally, the author puts forward several pieces of advice and countermeasures about how to build the economic systems by which water can be used economically.  相似文献   

6.
The article puts forward the process and means of regional water and land balance research, and then from two scenarios which are the balances under natural regulation and human intervention, calculated and analysed the balance between water and land on Ningxia Plain. For the balance under natural regulation named farmland water balance, using farmland water resource balance equation, the research estimated the monthly farmland" water balance of 8 major crops for all of the 12 counties on Ningxia Plain in the period of 1960-2001; for the balance under human intervention, the research estimated land-use water balance equation of the counties in 2000, and calculated the balance between land use and water resources including irrigating water of all the 12 counties on Ningxia Plain. Results showed that ①precipitation can not meet the water demand of the crops for growth and development on Ningxia Plain, and water shortage is the primary character of farmland water balance under natural regulation. ②the diversity of water and land balance of different counties is distinctly influenced by the crop structure, water quantity for irrigation and irrigation level. ③Irrigation water could meet the crop water demand on Ningxia Plain in 2000, but there was not much space to expand irrigating cultivated land.  相似文献   

7.
1 INTRODUCTIONWater shortage will be one of the common risks peoplehave to face in the 21st century. China, a country withwater shortage, possesses only as much as 1/4 of the world'smean occupation for every person and is enlisted as oneof the thirteen countries where water is in a great shortage.Furthermore, in China, the water resources distributionhas been terribly unbalanced from region to region. NorthChina, covering 15 provinces, possessing 45% of thefarmland and 38% of the populat…  相似文献   

8.
1 INTRODUCTION Environmental changes caused by mankind's exploitation and regional climate changes have long been a severe problem in the world, especially in the arid and semiarid areas because of their ecosystems' vulnerability (Chen & Qu, 1992; Wang & Cheng, 1999; Liu et al., 1999). During the last half-century, especially the last 30 years, drastic environmental changes have occurred owing to exploitation and development, which have invoked society's concerns. In the Qinghai-Tibet …  相似文献   

9.
1 INTRODUCTIONEvapotranspiration (ET) is the key process controlling theexchange of energy and hydrologic flux for vegetatedsurface. Terrestrial net primary productivity (NPP)represents the carbon available for plant allocation toleaves, stems, roots, defensive compounds, reproductionand is the basic measure of biological productivity. Treegrowth, forage available for grazing, food productivity,and atmospheric CO2 levels are all strongly controlled byNPP (White et al., 2000). The exch…  相似文献   

10.
Russian Journal of Ecology - To assess carbon dioxide exchange in the ecosystem of cowberry–lichen pine forest, 8790 eddy covariance measurements were made during the summer–autumn...  相似文献   

11.
Superfluous arsenic in drinking water can do harm to human health. In this paper, a broad overview of the available technologies for arsenic removal has been presented on the basis of literature survey. The main treatment methods included coagu- lation-sedimentation, adsorption separation and ion exchange, membrane technique, which have both advantages and disadvan- tages. It concluded that the selection of treatment process should be site specific and prevailing conditions and no process can serve the purpose under diverse conditions as each technology has its own limitations. In order to gain good results, some methods should be improved.  相似文献   

12.
In early 2009, few would have expected that the Intergovernmental Panel on Climate Change (IPCC) would come under such massive attack. The IPCC had enjoyed a pristine reputation and had even advanced to become a role model for biodiversity and food security assessments (Loreau et al. 2006; Watson 2005). However, public trust and, with it, the organization’s credibility eroded dramatically after November 2009 with the events that became known as ‘climategate’. This article seeks to contribute to current debates about how to reform the IPCC. It argues that there are major flaws in the design of the IPCC which are rooted in the linear model of expertise and which are helping to stoke the backlash against the IPCC. The article analyzes the ways in which the IPCC’s activities conform to the linear model of expertise and considers the consequences of this for integrating adaptation into the IPCC assessments. It explains why adaptation played only a marginal role up until the IPCC Third Assessment Report. It then demonstrates why the use of the linear model of expertise constrains the scientific and political debate about adaptation and leads to proxy debates about scientific evidence, which result in depoliticizing the politics of adaptation and politicizing science. Finally, the article calls for the debate to be opened up to accommodate alternatives that are both politically more feasible and at the same time more appropriate to the specific needs of adaptation policies at different levels of decision-making.  相似文献   

13.
Abstract

Water pollution is one of the major environmental problems, especially in urban areas. Due to rapid urban expansion and industrialization, water pollution in Zhengzhou City, the capital of Henan Province in central China has become a serious problem for its development. In this study, the surface water quality was evaluated using Nemerow Comprehensive Pollution Index (NCPI), and the change trend was calculated using methods of Mann-Kendall test and Sen’s slope estimator, based on the monitoring data from 1998 to 2008. The results show that the NCPI ranged from 3 to 50 in 70% of the monitoring cases, implying that most rivers were seriously polluted. However, this serious polltuon is expected to be gradually improved, as the concentration of water pollutants and NCPI declined significantly in most rivers. Water pollution in reservoirs was much lower than rivers, and the NCPI in the three monitored reservoirs was lower than 3 in most years, and shows a downward trend. Although the surface water quality was gradually improved, great efforts are still needed to enhance the protection and improvement of surface water environment.  相似文献   

14.
The presence of the synthetic estrogen 17α-ethinylestradiol (EE2) in waters at low levels is a concern due to its ability to act as an endocrine disruptor. Ozone (O3) is commonly used in water treatment and reacts with EE2 to form by-products having characteristics that are mostly unknown. The aim of this study was to identify the by-products of E2 and EE2 ozonation and determine their estrogenicity and toxicity relative to the parent compound. Ozonation by-products were identified via LC-MS analysis. The estrogenicity was measured using the YES assay, and toxicity was determined by monitoring effects on histology of fetal rat testes and testosterone secretion by these tissues. Two EE2 by-products were identified with open phenolic ring structures (masses 302 and 344 u). The Yeast Estrogen Screening (YES) assay showed a decreased but incomplete removal of estrogenicity after ozonation of EE2. Histological analysis of fetal testes revealed that neither E2 nor EE2, with or without ozonation, had any effect on seminiferous cord formation; however, a remarkable negative effect on testosterone secretion was observed, with EE2 by-products after ozonation showing the most rapid and extensive inhibition. These results show that the removal of EE2 via reaction with O3 resulted in the formation of by-products that are less estrogenic (as demonstrated by the YES assay), but have a greater negative impact on testosterone secretion. Thus, the disappearance of the parent compound is not a sufficient endpoint, as the by-products created may be more toxic. Care should be taken when implementing oxidation applications such as ozone during waste water treatment.  相似文献   

15.
Over 2500 species of invertebrate macrofauna and over 177 species of avifauna live in the forest–tundra of the Lower Ob region and adjacent areas of the northern taiga and shrub tundra. About half of the invertebrate species of the study area are northern—mostly hypo- and hemiarctic—tundra species; the rest are boreal and arctomontane-boreal Holarctic and trans-Palearctic species. The anthophilic and aerobiont insect assemblages include many boreal forest forms. A total of 153 species have been observed nesting at the taiga–foresttundra boundary; 81 species have been observed nesting at the tundra–forest-tundra boundary. The avifauna of the forest–tundra becomes enriched with taiga species in floodplain forests and with tundra species on the flat interfluve, in areas of tundra and tundra-like wetlands. The forest–tundra of the Lower Ob region has no avifauna and entomofauna of its own and contains a mixture of taiga and tundra faunas. It has been found that the ecotone effect is not pronounced in the taxonomic composition of birds and insects in the forest–tundra, where only some particular groups (such as amphibiont insects) have increased abundance.  相似文献   

16.
Russian Journal of Ecology - This study has been carried out to determine water quality of Sang? Stream (West Anatolia, Turkey) and to compare the performance of indices used. Five biotic and...  相似文献   

17.
River Nile is one of the longest transboundery rivers and it is shared and used by Burundi,Democratic Republic of Congo,Egypt,Ethiopia,Eritrea,Kenya,Rwanda,Sudan,Tanzania and Uganda.As of today,the Nile is a crucial resource for the economic development of the Nile Basin countries and a vital source of livelihood for 160 million inhabitants as well as 300 million people living in the 10 riparian countries.The Nile Basin Initiative(NBI) is one of the international cooperative river basin management program and regional partnership where all the Nile Basin countries except Eritrea unite to pursue long-term sustainable development,improved land use practices and management.This review therefore focused on the challenges not faced on NBI in terms of integrated use of the river and conducted analysis of strengths,weaknesses,opportunities and threats(SWOT) based on secondary data.The result of the review revealed that for decades,the Nile Basin people have been facing many complex environmental,social,economic and political challenges that have made it difficult for the proper management and sustainability of Nile water.The initiative provides training to develop skills in government ministries,non-governmental organizations and local communities in each country.It is also working to raise awareness of critical environmental issues by strengthening networks of environmental education practitioners;developing curriculum in the education sector.The challenges of NBI include the involvement and funding of World Bank,lack of sufficient staff,procedural and policies conflicts,lack of coordination and linkage with other regional institutions and lack of recognition as river basin organization.Considering the complex nature of the project,it is recommended that the NBI should come up with a strong multi-disciplinary monitoring and evaluation team to follow up all implemented projects.The NBI should carry out participatory land use planning in communities along the river basin.Moreover,livelihood analysis should be carried out especially in communities along the Nile to come up with poverty eradication projects which are socially acceptable,applicable,economically viable and affordable.  相似文献   

18.
An obvious need for an updated and comprehensive study prompted this investigation of the complex of environmental costs resulting from the nation’s dependence on pesticides. Included in this assessment of an estimated $10 billion in environmental and societal damages are analyses of: pesticide impacts on public health; livestock and livestock product losses; increased control expenses resulting from pesticide-related destruction of natural enemies and from the development of pesticide resistance in pests; crop pollination problems and honeybee losses; crop and crop product losses; bird, fish, and other wildlife losses; and governmental expenditures to reduce the environmental and social costs of the recommended application of pesticides.The major economic and environmental losses due to the application of pesticides in the USA were: public health, $1.1 billion year−1; pesticide resistance in pests, $1.5 billion; crop losses caused by pesticides, $1.4 billion; bird losses due to pesticides, $2.2 billion; and groundwater contamination, $2.0 billion.*Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   

19.
The horizontal distribution and quantitative characteristics of macrozoobenthos were studied in small lakes of the Darwin Nature Reserve (southern Vologda oblast). The aggregation index varied in the open areas of acid lakes, which indicated that communities of small acid water bodies were unstable. The aggregation was the lowest in the open area of a neutral lake. In acid lakes, the number and biomass of macroinvertebrates were the highest near the coasts. In the neutral lake, conversely, these values were maximum in open areas and low near the coast due to a strong pressure of predatory invertebrates and fish. An aggregating effect of invertebrate predators was observed near the coasts of lakes of different types.  相似文献   

20.
Residential water use is gradually becoming the focus in China‘s municipal water supply planning and management in recent years. Little is known, however, about the residential water use in modem China due to the transition of economy and enhancement of management on water conservation. In order to better understand the characteristics of residential water use in North China, a model for identifying the determinants of residential water use was established and analyzed by using panel data and cross-section data methodologies. Then Taiyuan city, the capital city of Shanxi Province in Northern China was selected as a case study. Both the analyses and field investigation indicate that the relatively slow increase of residential water use in recent years may result from the implementation of strict laws and regulations on water conservation. And through the investigation,first-hand information about water consumption pattern, water reuse/conservation, people‘s attitude toward water quantity and quality, etc. have been obtained.  相似文献   

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