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  • Original Articles
    CHEN Liqun,LIU Changming,LI Fadong
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    Base flow has important implications in water resources allocation, water security, food security, non point pollution assessment and investigation and water resource assessment. Base flow recession curves contain a lot of information related with hydro-settings. The paper first overviews the definitions of base flow. Then, base flow generation and loss mechanism and impact of hydrogeographical factors, rock kinds, climate condition, terrain, hydrologic condition and underlay ground were analyzed systematically. Impact of human activities, such as extraction of ground water, on different hydrogeographic settings, land use cover change(LUCC) and base flow was emphasized. Various kinds of base flow recession simulation methods, such as linear reservoir method, auto-regression simulation method, empirical function and method based on groundwater movement, were presented based on the characteristics of the basin; and the merits, demerits, and applied conditions of these function were illuminated. A series researches show non linear flow recession are more suitable than linear flow recession in recession simulation, which demonsfrates the non linear characteristics of out flow form aquifer. Base flow separation methods were reviewed. Above all, the water balance methods and the run-off simulation methods are sound based; but the graph method is subjective, which precision depends on applier's knowledge on the relation between ground water and river. In addition, some comments on the construction of the recession function are stated.

  • Original Articles
    On the Nature and System of Water Rights
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    Water scarcity is a crisis which threatens the development of China. Water institution innovation of water rights and water market is necessary for China to overcome water problems. Water rights should be viewed as natural resources property, with water resources (not water product),excluding ecological water demand, as its objects. water rights is thought to be private domain with the features of public domain and quasi-property with the features of typical one. In China, the country owns water resources. In the system of water rights, the property of water resources is the mother of the other water rights including possession right, use right, profitability right and disposition right, which could be departed completely or incompletely from the mother-body and transferred in the water rights market. In China, water is also called water-drawing rights, which could be divided into water-lifting right, water-ditching right, and water-sluicing right according to the methods of water drawing, or into water demand right of agriculture, industry, family and civicism activities according to the means of water utilization. The author don't agree with the opinions that the use right of water body(or water suface), water-draining right and the administration of water sector belong to water rights.

  • Original Articles
    ZHAO Wenwu,FU Bojie,LV Yihe,CHEN Liding
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    Improper land use by mankind is one of the main causes of soil erosion. Through changing vegetation cover, soil property and runoff velocity, land use affects the occurrence and development of soil erosion. As scale changes, notable changes will occur in the interactive mechanisms between land use and soil erosion. Currently, research on land use and soil erosion is changing from slope scale to small watershed, watershed, and regional scales. Examining the influence of land use on soil erosion at different scales has become a frontier field in contemporary research in physical geography. At slope scale, vegetation offers protection against soil erosion by reducing runoff and increasing soil resistance to sediment entrainment. Research has verified that the effects of different land use types on soil erosion vary obviously, and farmland may be the most susceptible land use to runoff and soil erosion for different areas. Land management practices, such as changing micro-terrain, exert important influence on soil erosion, and the common soil erosion models used at slope scale are USEL/RUSLE and WEPP. At small watershed scale(or watershed), more attentions are paid to the impacts of land use structure and land use pattern on soil erosion. There is correlation between some land use types and sediment yields, and changes in land use structure have a significant impact on soil erosion. The spatial variability of land use pattern may change the interception ability of land parcel, the hydrological structure and soil erosion systems, which impact the final sediment load at watershed scale. In order to identify the relationship between land use pattern and soil erosion, some distributed soil erosion models are often applied to simulate soil erosion rate under different land use patterns, such as LISEM, AGNPS, EUROSEM and SEDEM. At regional scale, there are some methods to carry out soil erosion evaluation. One way is by means of up-scaling methods to study soil erosion of large area. The up-scaling methods include: combining the monitoring data at related gauges in the region, and using soil erosion model at slope, small watershed scale or watershed scales for regional scale. The other way is to select some macro-factors for soil erosion evaluation. Land use has an important impact on soil erosion, and impacts of land use on soil erosion have been regarded as a hotspot and leading issue in scientific research of physical geography. There is a long run to go for land use and soil erosion, though great progress has been achieved so far. More attentions may be paid to scaling, effects of land use policy, land use pattern, soil loss process, and etc.

  • Original Articles
    CHEN Jianyao,WANG Ya,ZHANG Hongbo,ZHAO Xinfeng
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    More than 90 papers of the last 20 years on nitrate pollution in groundwater were reviewed, and the issue both in China and abroad was found focusing on the following aspects: the transform processes and mechanism of nitrate in groundwater, the form of pollution and the sources of nitrate, and the methods to avoid and treat nitrate pollution. The transform processes include: mineralization-immobilization, fixation, nitrification and denitrification. All kinds of nitrate are classified into point origin and area origin. There are two approaches, structural approache and non-structural approache, reported to deal with nitrate pollution in groundwater. The structural approach was well reported to dispose of nitrate in a local or point scale, while the non-structural approach could be adopted in the regional scale, but few case studies were reported. Techniques to treat nitrate pollution were well reported in China, e.g. carbon dioxide regenerated ion exchanger, bio-film-electrode process, etc. Nitrate pollution in groundwater is closely related to human activities, and the main sources of nitrate were identified as excessive application of commercial fertilizers, manure, and the irrigation by non-treated wastewater, etc. The main factors affecting the occurrence, distribution and change of nitrate in groundwater were identified as: · Dramatic increasing in population that requires much more food supply, · Urbanization that discharges too much waste to be absorbed by soil and water bodies, · Over use of fertilizer, · Poor management in water and land resources, · Land use and land cover change, · Public concern and policy issues, · Change in global food production and trade Three themes were thus proposed for further study in nitrate, given as follows: 1. Integration of nitrogen and water cycle and processes, with respect to nitrogen aspects of hydrological cycle (NAHC); 2. Interface processes and mechanism regarding nitrate transformation in soil, plant, atmosphere and groundwater; 3. Impacts of nitrate in groundwater in the interaction of land and ocean, and assessment of human activities, such as urbanization, food production and trade, on the change of nitrate in groundwater in the global perspective.

  • Original Articles
    DUAN Xiaofeng,XU Xuegong
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    As an ecologically vulnerable region where atmosphere, hydrosphere, geosphere and biosphere interact, the Yellow River Delta plays an important role both in economy and environment in China. The emergy theory is based on the theory and methods of the System Ecology. Forming 1J higher quality energy will need a large amount of lower quality energy. In other words, different forms of energy have different attributions. By dealing with the energy-value-process of ecosystem, the theory provides us with a new approach to the economic ecology. Based on emergy analysis, this article systematically analyzes energy, resource flowage and condition of eco-economy system in the Yellow River Delta. On the basis of the evaluation indicator system, resources-environment-economy system in the Yellow River Delta is assessed comprehensively. The results indicate that the total emergy consumption of the study region is about 1.76×1022sej,or about US$ 8.42×109. The waste emerge evacuated from the study region reaches about 5.74×1021sej,or about US$ 2.74×109, which indicates that environment in the Yellow River Delta degenerates rapidly because of the industrialization and economic increasing. Finally, based on the calculation of the emergy sustainable indices (ESI), we find that economy increasing of the study region depends on resources consumption. Although the value of resource reserves in the Yellow River Delta reaches US$ 4.45×1012 (about 529 times larger than GDP), it is difficult to use it adequately because of technical limits. So enhancing the resources utilization efficiency and reducing waste are the primary tasks in the future in order to realize sustainable development in the Yellow River Delta.

  • Original Articles
    WU Yingmei,ZHANG Lei,XIE Hui
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    energy production system;structural evolution;output effect;relativity analysis; energy resources in west China

  • Original Articles
    LIU Qinpu, LIN Zhenshan
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    Since 1981, the long-term vegetation data at Leymus Chinensis grassland in Inner Mongolia has been collected. This paper analyzes the triple relations among the vegetation, temperature and time based on the smoothed data that were treated with the method of moving average. The results show that the average minimum and maximum temperatures in winter (Oct. to Mar.) in this region increased faster than that in summer (Apr. to Sep.), and that the yearly average minimum and maximum temperatures increased from 1981 to 1994 mainly because of the increasing of minimum and maximum temperatures in winter, which were in line with the trend of global warming. In the meantime, the first 6 dominant species of this grassland responded to the temperature changes differently: the Importance Value (IV) and Aboveground Net Primary Productivity (ANPP) of the first, third and fifth dominant species, Leymus chinensis, Cares duriuscula, and Artemisia commutate, respectively, decreased because of global warming, and the IV and ANPP of the second, fourth and sixth species, Stipa grandis, Achnatberum sibiricum, and Agropyron michnoi, respectively, increased owing to species compensation for utilizing resources. So the Stipa grandis, the second constructive species, may replace Leymus Chinensis, the first constructive species, and gradually become the first one if these trends continue, and the structure and function of the community would change. Therefore the interaction of competition and compensation among dominant species should also be paid attention to when we study the response of species at the Leymus Chinensis grassland to the changes of temperatures, which is conducive to understanding the dynamic mechanism of individual species and entire community.

  • Original Articles
    MA Ting
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    The temporal changing trend, periodicity and spatial variation of PM10 concentration in Xiamen City measured in four different monitoring sites have been analyzed by using time series and simple statistics approaches including correlation analysis, principle component analysis and cross-correlation analysis. The results show the PM10 concentration had no significant increasing and decreasing trend from 2001 to 2002, but had significant periodicity (the most significant periods are 14 and 7 days for different monitoring sites). The spatial distributions of PM10 concentrations, however, are different with monitoring sites. The second PCA can describe the distribution difference exactly. The influences of meteorological factors, including air temperature, rainfall intensity, wind direction and rainfall days, on PM10 concentration have also been analyzed. Especially, the cross correlation analysis (CCA) was applied to estimate the influence of monthly rainfall days (MRD) on PM10 monthly average concentration (MAC). Meteorological factors can change the variation of PM10 concentration directly. The influence of MRD on MAC lags for about 2 or 3 months. Moreover, land cover types are also important to the spatial distribution of PM10 concentration. The local regions where the vegetation cover ratio (VCR) extracted from relatively remote sense data is high have relative low PM10 annual average concentration.

  • Original Articles
    HOU Shaofan,WANG Wuyi,LI Hairong,YANG Linsheng
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    High altitude area is a special eco-environmental system. The complex and changeful geographical conditions in high altitude area make the new migrations of human or animals affected by Mountain Sickness. The oxidative stress reaction induced by low of atmospheric and oxygen pressure and strong sun radiation is one of main causes of Mountain Sickness. In this paper, the relationships between different environmental factors in high altitude area and free radical reactions has been discussed in 6 areas. First, the results show that free radical reaction have significant negative relationship with atmospheric air pressure and oxygen pressure. Second, the native people in plateau can also be affected by free radical reaction as well as the new comer. Third, the native people in plateau can get an inherit adaptability. Forth, the inner nutrition materials can resist free radical reaction. Fifth, people exposure to high UV radiation would be easily affected by free radical reaction. Sixth, Low selenium and iodine in environment is also risk factors for people affected by free radical reaction. This study is not only of an important significance in understanding the free radical reactions induced by environment stress as well as the origin and evolution of native people, but also is practically valuable for studying the Mountain Sickness of crowds immigrating to high altitude areas as well as the sickness prevention and treatment. In addition, this study is valuable for the economic development and national defense construction in high altitude area. This study may provide valuable references for studying the regulatory effects of environmental factors on Mountain Sickness and their physiology in the Western Development of China.

  • Original Articles
    LI Yu,AI Hua,FENG Feng,DONG Suocheng
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    The environmental problem has become a new focus in domestic and foreign small town study. The environmental research of small town has vital significance to constructing the new socialism village and the harmonious society. It is necessary to review its development. Based on domestic and foreign points, this paper reviewed the newest progress of environmental research of the small town since 1990s, and commented the newest tendency of small town environmental research in domestic and foreign. Firstly, the foreign scholars in the majority paid attention to the small town environmental pollution type, industrialization and environment, environmental plan, environmental policy system and human settlement environment. The research results will be significantly referenced to constitute policy of small town environment in China. Secondly, the domestic scholars mainly made scientific researches on general environment questions in the small town, such as the small town settlement environment and its spatial distribution characteristic, sustainable development appraisement, environmental plan, ecological small town construction, environmental pollution characteristic and type, rural industry pollution, interactive mechanism between small town development and environment, and so on. Thirdly, the small town environmental research in domestic and foreign cannot keep up with the small town development. Finally, based on the above analysis, the article proposed the future research field and developing trend of the small town environment in China.

  • Original Articles
    LIU Ruimin,YANG Zhifeng,SHEN Zhenyao,DING Xiaowen,WU Xing,LIU Fang
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    Today, more and more research has focused on the issues of Global Environmental Change(GEC) and sustainable development(SD), and the study of land use/ cover change is a hot subject and front issue among all the researches. The serious eco-environment problems have been an obstacle to the economic and social development in upper reach of Yangtze River Basin, and the natural degradation also restricts the sustainable development for upper reach and all regions of Yangtze River Basin. Based on the DEM data, this paper analyzed the relationship of land use with elevation, slope and aspect in 2000. It is discovered in the result that the types of land use in upper reach of Yangtze River Basin in 2000 changed with different grade of elevation, slope and aspect. It is also indicated that these topographical factors have important influence on land use in upper reach of Yangtze River Basin. In order to protect the eco-environment and to promote the sustainable development in the upper reach and all regions of Yangtze River Basin, land use management should be enhanced based on the local condition. And further research should be developed to optimize land use and improve land cover with the influenced factors such as elevation, slope and aspect.

  • Original Articles
    LI Su, ZHUANG Dafang
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    With rapid development of RS and GIS technologies, RS and GIS have become the main means of population estimation. RS- and GIS-based population estimation methods can be divided into two categories in terms of the application goal and the required data information, i.e. areal interpolation and statistical modeling. Methods depending on whether ancillary information is used, areal interpolation methods can be further grouped into two categories: areal interpolation without ancillary information and areal interpolation with ancillary information. Statistical modeling methods can be further separated into five classes according to the difference of independent variables in the model, i.e. built-up area estimation method, land use density method, dwelling unit estimation method, image pixel characteristic estimation method, and physical and socio-economic characteristic estimation method. Different kinds of population estimation methods based on RS and GIS were reviewed following the aforementioned classification criterion. The application occasion, advantage and disadvantage, and research instance of all sorts of population estimation methods were analyzed. Finally, the issues necessary to be studied further in this field were put forward.

  • Original Articles
    WEI Xia,TANG Jiala
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    This paper introduces the concept and function of urban ecological park, analyzes the necessity of developing tourism for urban ecological park, discusses the object, principle and course of the tourism planning for China's urban ecological park, and tries to apply a reasonable developing frame to it. And then this paper takes Wenzhou Ecological Park as an example, describes its current situations and problems, explains the planning proposal for its tourism orientation, production and route, and expounds the importance of the transportation system and tourist interpretation system and the planning methods for them in tourism planning for urban ecological park. Furthermore, in this paper the different ways and tactics are always emphasized between tourism planning for urban ecological park and for general tourism planning, and the environment protecting techniques are also placed in a key position in order to make a more sustainable development.