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Table of Content

    25 February 2005, Volume 20 Issue 1 Previous Issue    Next Issue
    Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Calculation of Groundwater Recharge Volume after the Fifth Emergency Water Transfer to the Lower Reaches of the Tarim River, Xinjiang
    YANG Peng-nian, DONG Xin-guang, Omerjan
    2005, 20 (1):  1-6.  doi: 10.11849/zrzyxb.2005.01.001
    Abstract ( )   PDF (926KB) ( )   Save
    Tarim River is the longest inland river in China.It is located at the north of the Tarim Basin.However,the river flow in the 357-km-long section of the lower reaches had been cut off since 1972.The groundwater level had declined from 2.9~7.0m to 8.1~12.9m.In order to protect the eco-environment and save the existing vegetation in the lower Tarim River,a total volume of 13.8×108m3 of water was delivered to the lower reaches from May 2000 to July 2003, in five times.Based on groundwater monitoring data before and after the fifth water transfer,this paper analyses the features of responses of groundwater table pre- and post-delivery of water to the lower reaches of the Tarim River.Before water transfer,the groundwater table was generally a horizontal line but after that,it presented a binary polynomial curve. The relationgship of ground-water table and distance from the river was thus expressed binary polynomial.Furthermore,the calculative formula of groundwater recharge volume was established by means of groundwater balance.The results of calculation showed that the average depth of groundwater has come back respectively from 9.0m to 3.0m and from 9.0m to 7.4m at Yingsu section and Yiganbujima section in the vicinities of the river(0~1000m).The total volume of groundwater recharged was 8.01×108m3 after the fifth water transpfer.All these can provide referenced index for the evaluation of benefits from water transfer.
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    The Model of Resources and Environment Management of Urban Dry-up River in Northern China-A Case Study of Ecological Restoration and Reconstruction of Hutuo River
    CHANG Qing, LI Hong-yuan, HE Ying
    2005, 20 (1):  7-13.  doi: 10.11849/zrzyxb.2005.01.002
    Abstract ( )   PDF (372KB) ( )   Save
    With the development of economy and urbanization,urban rivers have been changed at different levels,such as channelisation,pollution and natural and cultural resource disappea-rance.The studies and practices concerning the alleviation and prevention of the degradated fresh-water ecosystems,and the restoration of the damaged ecosystems have drawn world-wide attention since the 1960s.Many studies have been carried out in recent years,but most of them were focused on monomial studies such as the treatment of lake and river eutrophication, protection and restoration of wetlands,etc,and the studies on urban river damaged most intensely by human were not enough.In light of the problems caused by the urbanization,such as river drying-up,the loss of landscape and biodiversity,deterioration of eco-environment,etc,this paper studied the model of ecological restoration and environment management of urban dry-up rivers based on the theories of restoration ecology,landscape ecology,and watershed ecology,and the measures of remote sensing,GIS,and environmental monitoring were used as the technique sup-port systems. The study took Hutuo river in Shijiazhuang as a case.Hutuo river is 61.335km long with an area of 199.51km2,consisting of such topographical units as riverbed,floodplain,etc.The average width of the river is 1.1km and the area of riverbed is about 66.69km2.Hutuo river belongs to Ziyahe drainage system which is the tributary of Haihe river,and it has become a typical urbandry-up river in northern China because of perennial flow breaking and deterioration of eco-envi-ronment year by year. Following the investigation and analysis of actual status of the eco-environment of Hutuo river,the paper raised the"green for water model".While meeting the ecological water require-ment,managing and modulating water resource rationally,the paper proposed the"Green Hutuo"model for restoring natural vegetation in the drainage area on the basis of suitable research criteria,that is:the river central district-indigenous herbage of flood retardance and water comp-lementarity;buffering area-bushes of water control and diversion,willow and poplar of bank prote-ction and construction;transition region-forests and fruit trees for controlling wind and fixing shifting sand.Finally,suggestions on resources and environment management were put forward. The paper provided a new notion and approach for resources and environment management of urban dry-up rivers in northern China.
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    Study on Water Resources Compensation in Songliao River Basin
    QIN Li-jie, QIU Hong
    2005, 20 (1):  14-19.  doi: 10.11849/zrzyxb.2005.01.003
    Abstract ( )   PDF (289KB) ( )   Save
    Songliao River Basin is one of the regions in northern China where water resource is short and water pollution and waste are very serious with constant water dispute following the construction of water conservancy projects.In order to ensure the sustainable utilization of water resources,water resources compensation system should be established.Water resources compen-sation can control water pollution and waste effectively and maintain stability and development of the neighbouring areas.The measures of water resources compensation identified in the paper are:to unify distribution of water consumption in the upper,middle and lower reaches of the basin,when the consumed amount exceeds the quota allocated in the upper reaches,the upper reaches will give the compensation to the lower reaches for the passive effect;in interregional water transfer those who develop and manage water resources or derive benefit should be responsible for the protecting,restoring and remedying the environment;when the eco-recons-truction takes place in the upper reaches,the lower reaches should give the compensation to the upper reaches for the ecological benefit;to establish the unloading right market in the whole basin to promote enterprises to save water resources and control water pollution effectively;and both the beneficiaries and intake areas should give the compensation to the storage and deten-tion zones.
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    Water Management: Theory and Method
    SHEN Da-ju
    2005, 20 (1):  20-26.  doi: 10.11849/zrzyxb.2005.01.004
    Abstract ( )   PDF (363KB) ( )   Save
    Management of water arises from the water cycle and water development & use. The interactions between water cycle and water development & use define the three management areas in water:resources management,service regulation and environment management.The resources management aims to avoid the "tragedy of the commons" in water resources;the service regulation is for the public benefits and control of natural monopoly; the environment manage-ment is to overcome the externality.In managing water,two types of instruments are employed:the entry restrictions and economic incentives.While assessing the application of these management tools, effectiveness, efficiency,justice and adaptability are four criteria.
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    Analysis on Runoff Supply and Variation Characteristics of Aksu Drainage Basin
    JIANG Yan, ZHOU Cheng-hu, CHENG Wei-ming
    2005, 20 (1):  27-34.  doi: 10.11849/zrzyxb.2005.01.005
    Abstract ( )   PDF (1051KB) ( )   Save
    Aksu River is the main tributary of the Tarim River,and its upper reaches are in the territory of Kirghizstan.According to gauging discharge of five representative hydrologic stations,this paper uses several statistical parameters to analyze both intra-annual distribution law and variation characteristics over years of different supply sources runoff.The result shows that the runoff supply of Aksu basin has the characteristics of zonal perpendicularity and diversification.The characteristics of annual discharge have close relationship with different runoff supply sources.On the one hand,intra-annual distribution of runoff is extremely uneven with high concentration degree,while on the other,the variation coefficient over years charge little with relative stable runoff volume changes.This paper applies the theory and method of wavelet analysis to perform multi-scale transformation of the annual runoff time sequence.The result reveals the annual discharge increase since 1990 in mountain area.The analysis of the influen-cing factors of precipitation and temperature indicated that the rise of temperature has greater influence on runoff increase than that of precipitation.
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    A Study of the Changing Trend of Chinese Cultivated Land Amount and Data Reconstructing:1949-2003
    FENG Zhi-ming, LIU Bao-qin, YANG Yan-zhao
    2005, 20 (1):  35-43.  doi: 10.11849/zrzyxb.2005.01.006
    Abstract ( )   PDF (571KB) ( )   Save
    Studies of cultivated land change in China have long been hampered by the lack of accurate and reliable data since 1949.By analyzing the cultivated land data from different sources in different phases after 1949,the paper considers the statistics with more errors happens during 1960-1985.According to the systematic data on land use gathered in the 1996 survey,based on reverse deduction of the cultivated land area from 1986 to 1996,and deduction of the cultivated land area from 1960 to 1985 by stages by employing yield of grain,this paper redescribed the actual changing trend and character of Chinese cultivated land and analyzed the driving force of the policy relative to cultivated land to cultivated land area change.The result indicated that the Chinese cultivated land amount has been fluctuating since the founding of New China in 1949.It increased as a whole before 1979,and decreased slowly since the 1980s.The cultivated land amount decreased rapidly after 1999 because of cultivated land conversion into land for ecological purpose,hence the problems of grain security and cultivated land security result from which need to be paid more attention to.In future,the pace of ecological cultivated land conversion will be slowed down gradually after a fast ecological rescue phase,the grain security and cultivated land security will become the main influencing factors which affect changes of Chinese cultivated land amount.With the strict implementation of cultivated land protecting policy,the Chinese cultivated land amount will keep steady after 2010.
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    Effect of Land Use Changes on Soil Conditions in the Developed Areas: A Case of Kunshan in Jiangsu Province
    GAO Zhong-gui, PENG Bu-zhuo, YU Jian-hua, PU Li-jie, ZHANG Lu
    2005, 20 (1):  44-51.  doi: 10.11849/zrzyxb.2005.01.007
    Abstract ( )   PDF (621KB) ( )   Save
    In order to study soil property change in the rapid urbanization and industrialization process,6 typical land use patterns were chosen to study the effect of different land use patterns on soil nutrient,soil pollution and so on in Kunshan,Jiangsu province.We drew conclusions as follows:Firstly,it is clear of the effect of land use change on soil nutrient,soil pollution.Besides the available-K,land use change results in the increase of soil nutrient from 1981 to 2002.And the change extent of organic matter,total-N and available-N contents is different in different typical land use patterns,the order of organic matter contents in 2002 is paddy field>garden land>uncultivated land>vegetable land,the order of total-N and available-N contents is paddy field>garden land>vegetable land>uncultivated land,the order of available-K content is garden land>paddy field>uncultivated land> vegetable land,and the order of available-P content is uncultivated land>vegetable land>garden land>paddy field.Secondly,the variation coefficients of organic matter and total-N content are apparently higher than other soil nutrients,and the variation coefficient of total-N content is the highest.Thirdly,land use change impacts heavy metal concentration,the Hg,Cr,Ni and Cd contents in paddy field are higher than the background level,and the Hg,Ni and Cu contents are higher in vegetable land,heavy metal concentration is lower in garden land and uncultivated land,but Ni content in garden land and uncultivated land is at the same level with other typical land.Finally,the land economic coefficient correlates highly with soil nutrient and soil pollution.
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    Urban Land Expansion and Farmland Loss in China
    TAN Ming-hong, LU Chang-he
    2005, 20 (1):  52-58.  doi: 10.11849/zrzyxb.2005.01.008
    Abstract ( )   PDF (1155KB) ( )   Save
    China is a developing country with a huge population and limited arable land resour-ces.At present,mean arable land area per capita is less than half of the world average.This limited arable land shows a trend of continuously decreasing with the rapid economic development and quick urbanization in the future.This paper firstly reviewed arable land changes in the process of urbanization in some developed countries,and then analyzed arable land changes in the Suzhou-Wuxi-Changzhou Region in southern Jiangsu Province based on land use data of 1990 and 2000.It was found out that considerable arable land was lost in the process of urbanization.Between 1990 and 2000,arable land in the Suzhou-Wuxi-Changzhou Region was reduced by 10%,mainly lost due to urban and rural settlements expansion.It was also found out that per capita land use in urban area of China was very close to that in rural area in the near future.This implied that it is not realistic to reduce land requirement for settlement by urbanization.It is highly possible that the anticipated rapid urbanization will accelerate the arable land loss,further threatening the national aim of arable land protection.
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    Resource Investigation and Assessment of Huperzia serrata
    WU Hong, ZHUANG Ping, FENG Zheng-bo, ZHANG Chao, JIN Chang-wei
    2005, 20 (1):  59-67.  doi: 10.11849/zrzyxb.2005.01.009
    Abstract ( )   PDF (473KB) ( )   Save
    The investigation of 35 wild sample stands,located in the main distribution area of Huperzia serrata in China with a total area of 71 300m2 in combination with the studies of more than 470 specimens of Huperzia serrata stored in 12 specimen houses as well as the existing documents, show that the main distribution areas of H. serrata are in the central and southern sub-tropical zones,with a total area of 2 600 000 km2 and an actual distribution area of some 390 000 km2. H. serrata is suitable in moist and shady areas located in evergreen broad-leaved forests in the central sub-tropical zone and the monsoon evergreen broad-leaved forests in the southern sub-tropical zone and its secondary biosystem. The field biomass investigation of H.serrata makes it possible to obtain the distribution data of varied areas. Combined with the systemic analyses of direct sampling results,and with indirect reasoning data and the assessment of environmental parameter,we determined that the natural storage capacity of H.serrata in China is 4 656.6t.Bassed on this figure,with manpower considered,the theoretical exploitation capacity is 1 604t.But taking into account of the current price of 30~40 yuan/kg,the commercial exploitation capacity can not exceed 200t.Because of the scattering status,and in more cases,the relative concentrated distribution areas are in the natural reserves and scenic spots,large-scale exploitation of H.serrata is not feasible.To evade the resource shortage of H.serrata, we must rely on other scientific and suitable approaches.The article also provides some new thinking and approaches to assess storage capacity and exploitation capatity of small plants.
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    Problems, Reasons and Strategies for Sustainable Development of Mining Cities in China
    FAN Jie, SUN Wei, FU Xiao-feng
    2005, 20 (1):  68-77.  doi: 10.11849/zrzyxb.2005.01.010
    Abstract ( )   PDF (1948KB) ( )   Save
    As a significant and necessitous issue,mining cities,especially the resource-exhausted ci-ties have already been given intensive attention by academic and governmental departments. From the perspective of sustainable development of mining cities,the intrinsic and extrinsic reasons for problems of mining cities are explored in this paper.Then,the economic benefits of mining cities are quantitatively analyzed using statistical data.Through the theoretical discussion of the sustainable development law of mining cities and demonstrative study on different types of mining cities in China,relevant strategies and measures are presented.The following conclusions are drawn: (1) The contradiction between cities and mining enterprises,which has been incorrect-ly dealt with for a long time,is the primary indigenous reason for the problems of mining cities.More seriously,the development gap,compared with non-mining cities,is becoming larger due to the domestic and international competitions.(2)As a whole,the level of economic development of mining cities,compared with the averaged level of countrywide cities,is lower.The economic benefit of miming cities is increasing owing to the economy of scale,and the economic situations of the oil-gots cities and iron-steel cities are comparatively better among all mining cities.(3)The premise that mining cities realize sustainable development is to fulfil the transformation of capital superiority so as to promote non-mining economy and substitute the mining economy step by step.
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    Study on Ecological Function Division of Resourceful City: A Case in Jiaozuo
    WANG Wei, BU Wei-na, JI Jiang-hai
    2005, 20 (1):  78-84.  doi: 10.11849/zrzyxb.2005.01.011
    Abstract ( )   PDF (867KB) ( )   Save
    The environmental problem of a resourceful city is more serious than other cities be-cause its resourceful industries occupy a great proportion amongst the others.Resourceful cities cry for researching on ecological function division so as to conform the relationship between development and environment.On the basis of environmental inquisition this paper summarizes the eco-environmental characteristics of Jiaozuo city and the existing problems.Using the technique of geographical information systems,integrating the expert's opinions and the method of quantitative analysis,the data on major factors of vegetation and forest resources,water and soil loss,water resources and water environment,biodiversity,and mineral resources exploitation are overlapped and analysized.Three ecological function regions and ten ecological function sub-regions are divided in Jiaozuo city,and the corresponding protection measures are put forward for different regions so as to lay the foundation for the improvement of the eco-environmental quality of the city.
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    Effect of Alfalfa Growth on Soil Water Environment in Hill-Gully Area of the Loess Plateau
    ZHAO Yao-yang, LIU Wen-zhao, PU Li-jie
    2005, 20 (1):  85-91.  doi: 10.11849/zrzyxb.2005.01.012
    Abstract ( )   PDF (723KB) ( )   Save
    Soil moisture plays a critical role in crop growth and vegetation restoration in the Loess Plateau.In order to analyze soil moisture's variation of the alfalfa plot and its impact on the soil water eco-environment,field experiments were conducted in 2002.At the same time, evapotranspiration of fallow land and some other crop fields were also studied as a contrast.The main results are as follows:(1)Precipitation in the rainy season plays an important role in the supplement of soil water in alfalfa plot.The soil moisture's dynamic period was identical with the rainy season,but the trend is getting dry.(2)Through a rainy season,the soil water content and soil moisture was declined in the alfalfa plot,but to the fallow land which were equal with the levels in April.(3)The same rainy season has different replenishment results on different crop fields.Alfalfa plot's evapotranspiration calculated in the top 3m soil layer was close to the millet and maize fields,higher than bean field,but lower than sorghum field.(4)The drying layer caused by long term's alfalfa's growing should be noticed.It's hard to recover the soil moisture in the dryed layer.
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    Experiment on Vegetation Rehabilitation and Optimization of Agro-forestry System in Karst Fengcong Depression (Peak Cluster) Area in Western Guangxi, China
    LI Xian-kun, LÜ Shi-hong, JIANG Zhong-cheng, HE Cheng-xin, LU Shu-hua, XIANG Wu-sheng, OU Zu-lan
    2005, 20 (1):  92-98.  doi: 10.11849/zrzyxb.2005.01.013
    Abstract ( )   PDF (505KB) ( )   Save
    There are about more than 54×104km2 of exposed karst areas in Southwest China where the serious karst rocky desertification is not only a geoecological disaster but also a main factor constricting the social and economic development of Southwest China.The karst fengcong depression area is the most difficulty one to control the rocky desertification and tackle the environmental problems.Longhe karst fengcong depression was selected to demonstrate rehabi- litation and restoration.Following the principles of ecology relating to rehabilitation of forest vegetation,the measures of structural adjustment of rural enterprises,optimization of agriculture internal developing proportion,and establishment of various effective models for sustainable agricultural development are the basic ways to remedy and reconstruct the ecosystem of karst area in Southwest China.The ecological restoration is a kind of ecological integrated engineering. According to the types of the barren hills and local weather conditions,the specific procedures are taken such as to close hillsides to facilitate afforestation, to construct pioneer communities,to practise optimized combination of indigenous species of arbor,shrub,grass,and vine,to select excellent local tree species,especially the fast-growth evergreen broad-leaved tree species as main species for woodland reconstruction,to develop special local products to promote economic development and environmental improvement.After 3 years experiment,the vegetation coverage of Longhe karst fengcong area increased by 27%,and the per capita farmer's income by 20%.
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    Research on Changes in Value of Ecosystem Services in Xilin River Basin
    XU Zhong-qi, LI Wen-hua, MIN Qing-wen, XU Qing
    2005, 20 (1):  99-104.  doi: 10.11849/zrzyxb.2005.01.014
    Abstract ( )   PDF (381KB) ( )   Save
    The change in value of ecosystem services in Xilin River Basin was studied using the ways that Costanza et al evaluated ecosystem services.The result showed that from 1987 to 2000, the total value of ecosystem services in Xilin River Basin decreased by 31.6%.Of all the ecosys-tems,the ecosystem services value of grassland dropped to 4.38×108$ from 5.13×108$;the ecosystem services value of wetland dropped to 0.9×108$ from 2.62×108$,and that of cropland rised to 0.03×108$ from 0.01×108$. Among the total value of grassland ecosystem services,the ratios of F.sibiricum steppe,S.baicalensis steppe,A.lymus + bunchgrass steppe and A.lymus + forbs steppe decreased from 1987 to 2000 and those of S.krylavii steppe and Ar.frigida steppe increased,indicating clearly that the steppe ecosystem in Xilin River Basin is degenerating seriously.It was concluded that the decline in value of ecosystem services in Xilin River Basin was resulted from the degradation of ecosystems and the decrease in area of the natural ecosys-tems.
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    Analysis of Coupling Degrees of Urbanization and Ecological Environment in China
    LIU Yao-bin, LI Ren-dong, SONG Xue-feng
    2005, 20 (1):  105-112.  doi: 10.11849/zrzyxb.2005.01.015
    Abstract ( )   PDF (454KB) ( )   Save
    Based on Synergistic Theory and the coupling rule of urbanization & ecological envi-ronment,the coupling degree model (CDM) of urbanization & ecological environment has been put forward,which is divided into coupling degree function and coupling coordination degree fun-ction.The temporal & spatial distribution of the coupling degrees and the coupling coordinationdegrees in China has been analyzed with CDM.The results show that:firstly,the coupling coordination degrees of urbanization & ecological environment are lower and the time sequence of their coupling degrees is basically at resisting stage from 1985 to 2002.Secondly,there obviously exists regional disparity of the coupling degrees and coupling coordination degrees,i.e., the coupling degrees in the eastern regions are higher than those in the middle & western regions;meanwhile,there exists spatial corresponding relationship between the coupling coordination degrees and the levels of economic development,which the coupling coordination degrees are higher in the provinces (regions) where the levels of economic development are higher,otherwise,the coordination degrees are lower.Thirdly,the spatial distribution of coupling degrees and coupling coordination degrees is inconsistent because of differences in economic development,historical evolution,natural environment and policies.Hence,people should adjust its relationship to avoid adverse effect of urbanization development on resources & environment.
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    Healthy Life of the Yellow River
    LIU Xiao-yan, SUN Yang-bo
    2005, 20 (1):  113-118.  doi: 10.11849/zrzyxb.2005.01.016
    Abstract ( )   PDF (137KB) ( )   Save
    Based on the study of evolution of the Yellow River,it's concluded that keeping healthy life of the Yellow River is important to promote harmonious co-existence of human and nature,and the river's healthy life very much depends on the social and economic conditions of human society.This paper analyzes the major challenges facing the Yellow River Basin Management nowadays,and describes the strategies and focus to harness the Yellow River at present stage.This study indicates that it is of higher priority to sustain sufficient Yellow River flow to ensure sediment transportation,self-purification and ecological water demand,and water saving and water transferring projects were necessary to optimize the water balance between water supply and water demand.Furthermore,the sediment management and river training works are also important approaches to keeping the healthy life of the Yellow River.
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    Impact of Climate Warming on Agriculture in Northwest China
    LIU De-xiang, DONG An-xiang, DENG Zhen-yong
    2005, 20 (1):  119-125.  doi: 10.11849/zrzyxb.2005.01.017
    Abstract ( )   PDF (916KB) ( )   Save
    Using data of 171 observations from 1961 to 2003 in Northwest China,mean monthly temperature,highest temperature,lowest temperature,accumulated temperature ≥0℃,≥10℃,and negative accumulated temperature <0℃ were collected to analyze response of climate warming on heat resource and impact of climate warming on agricultural production.The results showed that mean monthly temperature,highest temperature,lowest temperature and accumulated temper-ature ≥0℃ and ≥10℃ of 1987~2003 were significantly higher than that of 1961~1986,especially the lowest temperature increment markedly increasing and the increment of winter greater than that of summer,the lowest temperature rising played a main role on climate war-ming over Northwest China.The negative accumulated temperature <0℃ reduced obviously.As the trends of climate change appeared warming since the late 1980s in Northwest China,thermal resource increased,planting areas of heliophilous crops expanded,the planting area of north boundary of crops would extend northward which is favorable for animals to overwinter and spend spring.The negative impacts of climate warming on agriculture is greater than the positive.
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    Calculation and Analysis of the Value of Water Resources of Huaihe River
    ZHU Jiu-long, TAO Xiao-yan, WANG Shi-jun, TONG Jin-ping
    2005, 20 (1):  126-131.  doi: 10.11849/zrzyxb.2005.01.018
    Abstract ( )   PDF (197KB) ( )   Save
    The Huaihe River running through the eastern part of China is the main water source of the five provinces of Hubei,Henan,Anhui,Shandong and Jiangsu,and has great effect on the economic development of these regions.In this study,the Huaihe River is divided into five reaches according to the actual conditions of the river basin.The shadow price of water resources,that is theoretical water resources value for different water use departments in each channel reach is obtained by means of developing and seeking solutions of the model for optimizing allocation of the basin's water resources,which can provide scientific basis for the formulation of the level of water resources value of Huaihe River.
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    GIS-assisted Modeling of Temporal and Spatial Distribution of Soil Water Content in Loess Plateau- A Case Study in Anjiagou Catchment
    ZHANG Xiu-ying, FENG Xue-zhi, ZHAO Chuan-yan
    2005, 20 (1):  132-139.  doi: 10.11849/zrzyxb.2005.01.019
    Abstract ( )   PDF (1895KB) ( )   Save
    Soil water content is a key factor influencing the ecological environment in the Loess Plateau of China.Thus,modeling temporal and spatial distribution of soil water content in loess hill region is of theoretical significance in the ecological restoration and also of practical signifi-cance in land use management.This study is accomplished by employing water balance-based model.The research uses GRID data structure in the GIS software of Arc/Info and uses its AML (Arc Macro Language)to program to model the spatially distributed soil water content every ten days from April to October.First,the spatial distribution of precipitation is considered uniform according to the situation of the study area.Second,the SCS model is employed to calculate the distributed spatial runoff.Third,Butikle method is employed to model the distributed spatial actual evapotranspiration and the Hargreaves equation is used to model the spatial distribution of potential evaporation.Finally,we obtain the spatial distribution of soil water content in Anjiagou catchment area.The eligibility ratio of the simulated soil moisture is 83.146% through the measured soil data,which shows the method of dealing with the parameters of the water balance-based model is reasonable.
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    Study on Error and Its Pervasion of Temperature Estimation
    YOU Song-cai, LI Jun
    2005, 20 (1):  140-144.  doi: 10.11849/zrzyxb.2005.01.020
    Abstract ( )   PDF (1022KB) ( )   Save
    Estimation of temperature in no meteorological observation area is an important step in land surface process study.Altitude is one of the important proxies to estimate temperature. GTOPO30 is a global digital elevation model (DEM).Elevations in GTOPO30 are regularly spaced at 30-arc seconds (approximately 1 kilometer).GTOPO30 was used to meet the needs of the geospatial data user community for regional and continental scale topographic data. GTOPO30 and China meteorological data are applied in this study to analyze the estimated temperature error in each meteorological station and its pervasion during interpolation.The vertical temperature lapse rate is applied and assumed constant (0.0065℃/m) in China.The result shows that temperature error is between -5.3~+8.6℃ due to altitude difference between GTOPO30 and observed value.Error in point (meteorological station) diffuses to neighboring cells in the process of interpolation.Therefore,estimation of temperature as well as other climate parameter must take into consideration of the altitude difference between DEM and observed value.
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    Research on the Variation Characteristics of Eco-environment and Propagation Resources in Lalu Wetland
    LI Chun
    2005, 20 (1):  145-151.  doi: 10.11849/zrzyxb.2005.01.021
    Abstract ( )   PDF (499KB) ( )   Save
    During the period of 2001-2002,the variation characteristics of eco-environment and propagation resources in the last fifty years in Lalu wetland were investigated.The results showedthat influenced by human activities such as urban development,resources exploitation,agricultural production and stockbreeding,the area,water environment,plant species and communities,animal species of Lalu wetland had changed remarkably with time,differing from those in the early 1950s.The major characteristics are as follows:1) the area of wetland had been reduced from 12km2 to 6.2km2; 2) in the early times the wetland was inundated by water all the year round,but now only partial area was inundated by water with gradient of water level increased from 0.3~0.8m to 0~1.5m;3)compared with the number of plant species in the early times,32 species belonging to 31 genera and 13 families were increased in wetland,but some species of helophyte plant were reduced;4)in the early times,phragmites australis and carex communities were in domination,however,the horizontal structure of the communities in wetland today showed multiple communities intergrowth;and 5) compared with the early times,the bird number and fish species changed remarkably.Today,the bird species which can be seen frequently in wetland only totals five,the Carassius and Cyprinus carpio which didn't exist in the early times have become the only fish species in the wetland.
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