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Table of Content

    25 February 2006, Volume 21 Issue 1 Previous Issue    Next Issue
    Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Studies on Material Metabolism Response of Regional Land Use Change
    HUANG Xian-jin, YU Shu-tong, MA Qi-fang, LI Lu-lu, ZHAI Wen-xia
    2006, 21 (1):  1-8.  doi: 10.11849/zrzyxb.2006.01.001
    Abstract ( )   PDF (375KB) ( )   Save
    Based on descriptions of correlative studies,this paper firstly reveals the overall flows of food,energy,water,material and wastes into and out of the Greater Jiangsu Area quantitatively.At present,as the material resources are rapidly reducing,the increase in material metabolism efficiency has become more and more important to the development of human society.Then it analyzes the mechanism of the impact of land use change process(such as the change of land use manner,land use intensity and allocation of land use) on material metabolism taking Jiangsu province as a case.A driving force model has been established.It turns out that with constant increase in land use intensity the material metabolism flux has also increased rapidly since 1989.The higher the land use intensity is,the greater the flux value of material metabolism.Hence,the more the resources consumed and the pollutant discharged,the greater impact on the environment will be exerted.In other words,the smaller efficiency value of material metabolism is related to the less unit GDP resources consumed and pollutant discharged.When land use intension rises by 10%,the material metabolism flux will rise by 5.62%.Every 10% rise in land use intensity can lead to a ascend of 5.03% of the material metabolism efficiency.Though the efficiency of material metabolism has been improved,the scarcity of material resources became more and more serious.So it is necessary to further improve the efficiency of material metabolism.Finally,the direction of the study is put forward about the material metabolism response to regional land use change.
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    The Changing Characteristics of the Agricultural Land Use Intensity in China Based on the Production Cost
    LIU Cheng-wu, LI Xiu-bin
    2006, 21 (1):  9-15.  doi: 10.11849/zrzyxb.2006.01.002
    Abstract ( )   PDF (269KB) ( )   Save
    Based on the value cost databases of the main crops such as paddy,wheat,maize,cotton,flue-cured tobacco,sugarcane and beet,this paper studied the changing characteristics of the agricultural land use intensity in China during the period 1980-2002.The results showed that:(1)The degree of intensity of the agricultural land use has increased in the last two decades in China,but the degree of intensity declined three times in 1985,1993 and 1998.(2)The increase of the degree of intensity of land use was mainly resulted from the increase of the material cost,but the change of the labour force was the key factor leading to the change of the degree of intensity.(3)There was no essential difference in the intensity changes between different crops;but the characteristics of the degree of intensity of the cultivated land use changes differed from each other between different regions.(4)The increase of the land use intensity in undeveloped regions was greater than in developed regions.The increase of the land use intensity in the developed regions mainly depended on the input of the material cost,and the addition of the labour force cost is not evident.However,in the undeveloped regions the input of the labour force cost equalled the material cost,especially since 1991,the input of the labour force cost has exceeded the input of the material cost.In the period of the decline of the degree of intensity,the decline extent of land use intensity in the developed regions was greater than in the undeveloped regions.
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    Comparative Study on Potential Water Resources for Tianjin
    LI Xiao-feng, ZHANG Hong-ye, DENG Xiao-wen, GAO Lu, WANG Yuan
    2006, 21 (1):  16-23.  doi: 10.11849/zrzyxb.2006.01.003
    Abstract ( )   PDF (198KB) ( )   Save
    As a city with serious water shortage problem,Tianjin has an urgent need to find new water sources in order to meet the growing demand for water supply.The standby water sources schemes in Tianjin include middle and east routes of south to north water transferring from Yangtze River,importing water from Yellow River,redeploying water from upstream reservoirs of Haihe River,effluent reuse,seawater for direct use,seawater desalination,saline ground water development,etc.In our research,we use analytic hierarchy process to evaluate these schemes with a comprehensive analysis on nine factors,including water supply,difficulty of water source sharing,annual volume of water supply,cost of engineering construction,quality of water,cost of water treatment,cost of water supply pipelines reticulation,handicap of wastewater disposal process and risk of eco-environment.First we analyzed each scheme with the nine factors.Then we used Delphi technique to decide the relative importance of these factors and got a judgment matrix to acquire the weight of them.As a result,seawater desalination got the highest value with the virtue of huge quantity of reserves,high quality of water supply,low ecological and climatic risks and short distance of intake.The middle route water transfer project,saline ground water and direct use of seawater also got higher mark profiting from large reserves,extensive and lower cost.The comparative assessment result indicates that these four schemes are felicitous water sources for municipal utilization in Tianjin.The east route water transfer project,redeploying water from upstream reservoirs and importing water from Yellow River got lower values with disadvantage of water pollution or serious regional contest.They can be only treated as contingent water sources.Although sewage disposal got the lowest mark because of high cost of treatment and supply pipelines construction,sewage treatment must be given priority to be used in irrigation,ecological and landscape demand.
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    Preliminary Analysis of Hydrological and Water Resources Effects under the Impact of Water and Soil Conservation Engineering in Fenhe River Basin
    QIU Ya-qin, WANG Shui-sheng, JIA Yang-wen, WANG Hao, ZHOU Zu-hao, HU Dong-mei, YAN Deng-hua, LI Juan
    2006, 21 (1):  24-30.  doi: 10.11849/zrzyxb.2006.01.004
    Abstract ( )   PDF (376KB) ( )   Save
    According to the application of the distributed hydrological model(WEP-L model) with physical mechanism to the simulation of the hydrological cycle under different underlying surface data,this paper analyzes the quantitative influence of water and soil conservation engi-neering on hydrological cycle and water resources taking Fenhe River Basin as an exapmle.Two cases were described.Case I,the simulated underlying surface data in 2000 was used.Case II,the underlying surface data displacing the water and soil conservation engineering in 2000 with bare soil was used in the model.By contrast between Case I and Case II,the change and evolution of hydrological cycle and water resources have been investigated.The results showed that the local hydrological cycle as well as the quantity and compositions of water resources change distinctly under the impact of water and soil conservation engineering.Three main variations are as follows:(1)the vertical process of hydrological cycle was strengthened,each part of which including interception of surface,infiltration to soil,evaporation of soil and recharge of groundwater increased by 9.4%,1.8%,2.2% and 0.5%,respectively;(2)the horizontal process of hydrological cycle was weakened,each part of which such as direct surface runoff and base runoff decreased by 51.7% and 1.8% but interflow increased 4.9%;and(3) the surface water resources decreased 29.7% but groundwater resources nonoverlapped with surface water increased 5.1%,the special water resources reduced 23.2% but the general water resources increased 32.5% accompanied with 50.4% increase of the effective evaporation,namely,effective utilization of precipitation.The research achievement can be referenced to the studies on hydrological and water resources effects under impact of water and soil conservation engineering in other large watersheds.
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    Change in Pan Evaporation and the Influential Factors over China: 1956-2000
    REN Guo-yu, GUO Jun
    2006, 21 (1):  31-44.  doi: 10.11849/zrzyxb.2006.01.005
    Abstract ( )   PDF (741KB) ( )   Save
    Trend of pan evaporation and the related climate factors for the entire country and ten discharge basins of China are analyzed using a data set of total 600 stations.A significant decreasing trend in pan evaporation for the country as a whole has been found for the period from 1956 to 2000,with eastern,southern and northwestern China experiencing the most marked decrease.Eight of the ten discharge basins are found to be weaker in evaporating presently as compared to 1950's and 1960's,while two of them,the Songhuajiang Basin and the rivers of southwestern China,witnessed no significant change.The most significant decline occurred in the Yangtze River,Haihe River,Huaihe River,Zhujiang River,and northwestern rivers basins.The decrease is most obvious in summertime in the Yangtze and Huaihe rivers,in springtime in the Zhujiang and Liaohe rivers,and in both summertime and springtime in the Haihe River and northwestern rivers.The Yellow River,southeastern rivers and southwestern rivers are characterized by a decrease with no season being dominant,and the Songhuajiang River has no season when pan evaporation decreased significantly.In most parts of the country,a significant positive correlation of pan evaporation with sunshine duration,average wind speed and daily temperature range can be found.With the change of pan evaporation,these variables also experienced an evident negative change,indicating that they might have played an important role in the change of pan evaporation.It is more uncertain for air temperature and relative humidity,which show a good relationship with pan evaporation only in areas where no significant decrease occurred,indicating that they are generally not the main climate factors affecting pan evaporation.Possible causes for the evident decrease of sunshine duration and mechanisms for the climate factors to affect pan evaporation are also discussed in the paper.
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    Study on Zoning of China's Integrated Land Consolidation
    FNEG Zhi-ming, PAN Ming-qi, ZHANG Jing
    2006, 21 (1):  45-54.  doi: 10.11849/zrzyxb.2006.01.006
    Abstract ( )   PDF (222KB) ( )   Save
    Based on the comprehensive analysis of the geographical differentiations in China's land resources,its present conditions of exploitation and utilization and the problems resulting from the processes,using some scientific principles and indexes,and combining both the methods of"top down"and"bottom up",we formulate a zoning system for China's integrated land consolidation(CILC)with 11 land consolidation regions and 56 land consolidation sub-regions that covers the whole China at the county level by virtue of technologies such as computer analysis,GIS analysis,etc..The 11 land consolidation regions are:Ⅰ Qinghai-Tibet Plateau Region;Ⅱ Northwestern Arid Region;Ⅲ Middle Reaches of the Yellow River Region;Ⅳ Sichuan-Shannan Basins Region;Ⅴ Yunnan-Guizhou Plateau Region;Ⅵ Northeast Mountains and Plains Region;Ⅶ Northern China Plain Region;Ⅷ Middle and Lower Reaches of the Yangtze River Region;Ⅸ Hilly and Mountainous Area South of the Yangtze River Region;Ⅹ Southeast Coast Region;and Ⅺ Oceanic Region. Based on these conclusions,we've also put forward a preliminary assumption of"Diamond Country Land"for implementation of China's overall planning.And the general principles for regional coordinated development and some policies and suggestions or advises for CILC are given.
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    Spatio-temporal Characteristics of Urbanization Area Growth in Nantong City,Jiangsu Province
    CHU Jin-long, MA Xiao-dong, GAO Shu, XU Jian-gang
    2006, 21 (1):  55-63,165.  doi: 10.11849/zrzyxb.2006.01.007
    Abstract ( )   PDF (511KB) ( )   Save
    The spatio-temporal characteristis of urbanization area are important indices to evaluate and/or show the regional social and economic development.Nantong,a medium sized city affiliated to Jiangsu province,is located in north of the Yangtze Delta with developed economy in China and alongside the Yangtze River,whose opposite is Shanghai.Based on the Landsat TM/ETM satellite images acquired in 1984,1991,1997,2000 and 2003,as well as information extracted on urbanization areas including urban area,town area and county seat area with the help of GIS,we analyzed in details the spatio-temporal characteristics including urban expansion process,morphologic change,structure differentiation of growth speed using some indices such as growth speed,growth intensity,fractal dimension,spatial autocorrelation index and so on.Additionally,the characteristic of spatial pattern was also analyzed on the basis of the above-mentioned iodices.The result shows:(1)the growth speeds of all kinds of urbanization area are accelerated,and the growth intensities enhanced gradually from 1984 to 2003;(2)in the 1980s,the growth of urbanization areas was dominated by central city expansion,but since the 1990s by county(city) seat and the administrative towns;(3)the fractal dimensions of urban land use inc-reased gradually,which indicates that the town growth is unsteady,attributed to the acceleration of regional urbanization process and limitations of natural conditions;(4)the types of urban land growth are mainly centralized on the middle and lower speed of expansion;and(5) the spatial au-tocorrelation characteristics of urbanization area growth speed and intensity are not evident.But some individual type presents the cluster distribution tendency to some degree.For example,the high value regions of urbanization area growth speed are distributed along the Yangtze River and along some main communication lines.Whereas the high value regions of expansion intensities are distributed around the central city.
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    Zinc Accumulation and Pollution Risk in Soils Under Different Land Use Types in Beijing
    ZHENG Yuan-ming, SONG Bo, CHEN Tong-bin, ZHENG Guo-di, HUANG Ze-chun
    2006, 21 (1):  64-72.  doi: 10.11849/zrzyxb.2006.01.008
    Abstract ( )   PDF (478KB) ( )   Save
    Zinc is an essential element for animals and plants,and is of widely concern in agricul-tural sciences and environmental sciences,but the point to be concerned by the two fields aboves not always the same.Zn is commonly considered as a beneficial element by agricultural scientists who pay more attention to its positive effects on plant,while environmental scientists always take Zn as one of the heavy metals and give more attention to its negative effects on environment.According to a report by FAO in 1967,it's very common for Zn deficiency for the soil in the world,such as most of the countries in Europe,and a majority of states in USA.According to the data of the Second National Soil Survey of China,the area of Zn deficiency soil reached to 0.49×108ha,accounting for 51.1% of the total cultivated land. Beijing,capital of China,is located between 116°20′E and 39°56′N and surrounded by mountains on the west,the north and the northeast.Lying in the northern part of North China Plain,Beijing covers a total area of 16 808km2.Of which 10 418km2 are mountainous areas,or 62% of the total area of Beijing,while plain area covers 6 390km2,or 38% of the city's total. Information on the environmental effects of different land uses is lacking,especially in Beijing.Such information is important for the understanding of the sustainable development and regional agricultural planing.To identify the effects of land use on the accumulation of Zn in the soils,630 samples were obtained from 7 land-use types of Beijing,including park,vegetable field,paddy field,orchard,greenbelt,cornfield and natural soil,and their zinc was determined with Flame Atomic Absorption Spectrometry(FAAS).It was found that there was a rather large difference of the accumulation of soil Zn under different land use types.Compared with background concentration(GM=57.5mg·kg-1) of zinc in soil of Beijing,the accumulation of Zn in the park soils(GM=83.3mg·kg-1),orchard(GM=70.0mg·kg-1),paddy fields(GM=68.6mg·kg-1),greenbelt(GM=66.3mg·kg-1) and vegetable fields(GM=63.6mg·kg-1) was significant,while that of cornfields(GM=56.9mg·kg-1) and natural soils(GM=59.7mg·kg-1),accounted for the majority of the total samples,were not significantly different from background concentration.Using the Zn baseline concentration,product of geometrical mean(GM) and square of geometrical standard deviation(GSD),of soil in Beijing(97.2 mg·kg-1) as background,the ratios of soil samples exceeding the set standard in park,orchard,vegetable field,cornfield,and greenbelt were 25.8%,23.8%,9.7%,2.6% and 7.7%,respectively,while the overall ratio for the study was 6.4%.According to this investigation,some anthropogenic factors such as metal smelt,traffic,application of zinc-contained fertilizers and pesticides,sewage irrigation,and incineration of waste and landfill of waste,played quite important roles in the accumulation of soil sample Zn.According to the geometrical mean of Zn in the soil,the order of the 7 land-use types,from the highest to the lowest in Zn concentra-tion,was park soil>orchard>paddy fields>greenbelt>vegetable fields>natural soils>cornfields. In general,from the viewpoint of agricultural production and human health,there is a zinc deficiency on the whole in soils of Beijing,and zinc pollution is not obvious.
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    Assessment of the Coordinated Development Level between Grain Production in Heilongjiang Province and Wetland in Sanjiang Plain
    YAN Dong, XIA Jun, WANG Li-xin, LI Yun-cheng
    2006, 21 (1):  73-78.  doi: 10.11849/zrzyxb.2006.01.009
    Abstract ( )   PDF (192KB) ( )   Save
    There are always contradictions between grain production and wetland protection,but the reality requires that these two aspects coexist harmoniously.In order to seek a rational proportion between the sown area of crops and wetland area in Heilongjiang Province,this paper first uses fuzzy appraisal method to evaluate the benefits of grain production in Heilongjiang Province and of the wetland protection in Sanjiang Plain in past years.On this basis,the coordinated development level reflecting the degree of harmonious coexistence of the two aspects has been assessed.The result shows that the grain production was relatively coordinated with the wetland environment from the end of the 1970s to the beginning of the 1980s.During this period,the sown area of the crops was 870×104ha and the wetland in Sanjiang Plain was 195×104ha,which can be taken as a reference standard when defining the level of wetland restoration.Under this standard,Heilongjiang Province can provide 2 930×104t of grain at high per unit area yield level and the species of plants and birds of Sanjiang Plain wetland can resume to about 70% and 80% of the level at time the PRC was founded respectively.
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    Study on the Climate Change Trend and Its Catastrophe over "Sanjiangyuan" Region in Recent 43 Years
    LI Lin, LI Feng-xia, GUO An-hong, ZHU Xi-de
    2006, 21 (1):  79-85.  doi: 10.11849/zrzyxb.2006.01.010
    Abstract ( )   PDF (427KB) ( )   Save
    Using air temperature and precipitation data in 1962-2004 of 14 meteorological stations over "Sanjiangyuan"(head waters of three rivers) region,the changing trend of climate factors and its abrupt changes in evaporation and precipitation as well as air temperature are analyzed.The results show that the seasonal mean air temperature and annual mean over "Sanjiangyuan" region has been rising in recent 43 years,the rising of annual mean air tempera-ture is caused by the rising mean air temperature in summer and autumn;the variation of precipitation in a year,summer and autumn has been slightly decreasing,while the precipitation in winter,and spring has been increasing,and the warming and wet variation is featured in different seasons;the annual and seasonal variations of evaporation have been increasing under the condition of air temperature's rising,and precipitation is regarded as the main material resource of evaporation.Its variation trend,to some extents,causes the variation characteristics of evaporation.The climate change shows significant regional difference,the orographic factor of latitude,longitude and sea level has a significant influence upon the climate change,and annual mean temperature presented abrupt change in 1987 which is consistent with air temperature over the northwest region,but the abrupt change occurred earlier than that in northern hemisphere.The precipitation in winter and spring presented an increasing trend in the 1980s and the mid 1970s,and abrupt change in annual evaporation appeared in 1986-1988.Due to global warming,the evapotranspiration on land surface and evaporation on ocean has been increasing;as a result,the water-vapour cycle was accelerated,which is the main cause of warming/wet variation over the "Sanjiangyuan" region.
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    A Distributed Monthly Water Balance Model for Identifying Hydrological Response to Climate Changes and Human Activities
    WANG Gang-sheng, XIA Jun, WAN Dong-hui, YE Ai-zhong
    2006, 21 (1):  86-91.  doi: 10.11849/zrzyxb.2006.01.011
    Abstract ( )   PDF (298KB) ( )   Save
    A blueprint(FH69 blueprint) for a physically-based digitally simulated hydrologic response model was published by Freeze and Harlan in 1969,which initiated the studies on the distributed hydrological models(DHMs) at the watershed scale.Nevertheless,in spite of three decades of modeling development,distributed hydrological models are today being used in practice only at a fraction of their potential.The applications of DHMs based on the FH69 blueprint are confronted with difficulties because of deepening in theory,which simultaneously indicate that the complex models are not always good ones.According to the scientifically modeling protocol,a simple monthly subbasin-based water balance model is put forward,where the revised Bagrov evapotranspiration model is developed to parametrize the distinguishes between various land covers,and a parameter set is introduced to represent the impacts of human activities on runoff generation and evapotransipiration processes.In the case study of the Chaobai River Basin in North China,the model was used to quantificationally identify the impacts of climate changes and human activities on runoff.In the Bai River Basin,the annual mean precipitation of the 1980s(1980-1988) and 1990s(1989-2001) decreased by 9% and 5% com-pared with that of the 1970s(1961-1966 and 1973-1979),but the runoff reduced by 54% and 52% respectively.The simulation results indicate that the contribution rates of climate changes and human activities are 44% and 54% respectively.In the Chao River Basin,such contribution rates are 24% and 74%,i.e.,human activities are the main reason for runoff decrease.
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    Cost of Ecological Restoration in the Farming-pastoral Zone of Northern China
    XIANG Wei
    2006, 21 (1):  92-99.  doi: 10.11849/zrzyxb.2006.01.012
    Abstract ( )   PDF (286KB) ( )   Save
    The Farming-pastoral Zone of Northern China is a key region of ecological restoration,the central government has formulated relevant policies to encourage farmers and the region to convert cultivated land into forest and grassland,and for grassland fostering,including eco-compensation.The cost of ecological restoration is the scientific base for eco-compensation and the increase of the sustainability of the project.However,the former research about always pay less attention to eco-construction making more surplus working time and less working chance,which lessen the practical value of research.In view of the Scientific Concept of Development,the region is comparatively poor with simple employment structure,so the cost system should be centralized on the demand of the farmers,the conflict between economic development and eco-construction should be solved and the relationship between eco-construction region and benefited regions should be harmonized.Only the three problems are taken as a whole,can the cost system be put into use.Based on the above considerations,the paper designed a cost system which consists of cost of construction(CC),opportunity cost(OC),cost of development(CD).CC and OC are more understandable,and also have been calculated precisely.For the CD,we defined it as the cost to solve the unemployment problem resulting from land use change.Using the method on the west of Jilin province,the costs for three different measures in eco-construction,including conversion of cultivated land into forests and grasslands,and for grassland fostering,are respectively 24 150,8 090 and 967 yuan/ha,which are higher than the national and local govern-ment compensation standard,because CD is neglected by the government.As worrying about future work chances,the local farmers are not so active in eco-construction.How can solve the problem with the limited financial strength﹖Except the state subsidies,based on the principle of"who benefited,who pay",the cities of Changchun and Jilin should help to pay the CD,by means of pre-job training,technical support and so on.Finally,this paper put forward some suggestions on the specifications of compensations standard and the practice of mainstay multi-payment.
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    Change of Forest Landscape Service Function under Timber Harvest
    LI Yue-hui, HU Zhi-bin, CHANG Yu, HU Yuan-man
    2006, 21 (1):  100-108.  doi: 10.11849/zrzyxb.2006.01.013
    Abstract ( )   PDF (470KB) ( )   Save
    Analysis and evaluation on the forest ecosystem service function and the effect of anth-rotropogenic activity on it is a hot issue in both economy and landscape ecology.This paper aimed at identifying(1) how does the ecological function of forest landscape change after long-term management﹖(2) how does the spatial distribution of ecological function change﹖and(3)What is the quantitative relationship between econo-mic benefit from timber production and ecological benefit caused by timber harvest﹖To answer those questions,we employed forest stand map and timber harvest map as the source of information and used forest service model from cited paper,hen selected four service functions including water-holding,soil-and fertilizer-holding,carbon sequestration and oxygen release to valuate the forest service function change in space from 1989 to 2000 within Yalihe of Huzhong Forest Bureau in Greater Hinggan Mountains.Meanwhile,we created harvest patches distribution map in order to estimate and compare the ecological loss caused by timber harvest and economic benefit.The results show that the total forest service value within Yalihe decreased from 0.185 billion yuan in 1989 to 0.137 billion yuan in 2000.Area with more than 200 thousand yuan per ha declined from 47.75% in 1989 to 13.52% in 2000 and shrunk far away from the main river.Area with 50-100 thousand yuan per ha increased greatly from 11.63% to 28.46%;and patches became more in size and number.The decrease in function value is due to timber harvest and loss of ecological benefits is 0.067 billion,which is about 1.9 times as many as the loss from timber economic benefits.In fact the ecological loss is far more because it will be a long-term process.The loss of ecological benefits shows a similar trend to timber yield during the last 10 years.Finally,the service function distribution across three management grade areas revealed that in harvest-profited area,the function value per ha is the lowest,only 3 254 yuan,so harvest-profited measure will benefit forest reforestation,neverthe-less,hectare value is the highest,being 3 845 yuan in forest production,then the low harvest timber will ensure the high service value.So our the management policy was proved to be reasonable from the point of view of forest services value change.Classifying management grade area and controlling the harvest volume will benefit restoration of vegetation and service function.This work gives contribution to not only the forest ecosystem service function research but also landscape ecology.It is a particular way to reveal anthropogenic activity intensity in space.Additionally,this work provided new view to evaluate the forest management policy.
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    Effects of Excessive Grazing on Grassland Eco-system Services Valuation
    WANG Jing, WEI Yuan-ming, SUN Xu-ying
    2006, 21 (1):  109-117.  doi: 10.11849/zrzyxb.2006.01.014
    Abstract ( )   PDF (214KB) ( )   Save
    Grassland eco-system service provides a natural environment condition and function that grassland eco-system forms and sustains human being survival.And it does not only offer raw materials for husbandry,but also some regulating and supporting services.In fact the latter function and their values are most important,but usually neglected.In recent 20 years,excessive grazing has exerted severe negative influence on grassland eco-system services,especially on its environment sustaining service,and the resultant economic losses are very great. Thus this paper discusses the effects of excessive grazing on grassland eco-system services values,by taking Maqu county as an example and analyzes its grassland conditions by taking grassland conditions in the 1980s as pre-excessive grazing and the present conditions as post-excessive grazing.Firstly,based on the analyses of grassland eco-system,the index system of effects of excessive grazing on grassland eco-system services valuation was constructed,includingood production,atmospheric regulation,nutrition circulation and storage,erosion control,water conservation and environmental purification.Then by choosing reasonable ecological economic methods and parameters based on other's researches,assessment method of every index was established.Finally,using the above methods,the economic losses of excessive grazing were primarily estimated. The results showed that economic losses in food production,atmospheric regulation,nutrition circulation and environmental purification values of grassland in Maqu county in the 1980s were 4.28×108 yuan,2.96×109 yuan,2.84×108 yuan and 8.3×107 yuan,respectively,while at present those values were 2.78×108 yuan,1.92×109 yuan,1.85×108 yuan and 5.4×107 yuan,respectively.Due to excessive grazing,the economic losses of food production,atmospheric regulation,nutrition circu-lation and storage,erosion control,water conservation and environmental purification services were 1.50×108 yuan,1.04×109 yuan,0.99×108 yuan,1.02×107 yuan,3.94×108 yuan and 2.9×107 yuan,respectively.The total economic losses reached 1.72×109 yuan,in which direct economic losses accounted for 8.7%,and indirect economic losses were enormous and accounted for 91.3%.Among these services,the values of atmospheric regulation and water conservation services were higher,while those of erosion control and environmental purification services were lower.
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    Simulation of Carbon Sequestration Potential of Paddy Soils in Hunan Province,China
    LIU Shou-long, TONG Cheng-li, ZHANG Wen-ju, WU Jin-shui
    2006, 21 (1):  118-125.  doi: 10.11849/zrzyxb.2006.01.015
    Abstract ( )   PDF (370KB) ( )   Save
    Organic carbon sequestration of paddy soils plays an important role in mitigating the global warming.China is the largest country of rice production in the world,and for UNFCCC,carbon sequestration status,potential and corresponding measures to enhance the carbon stocks of rice cultivation system should be investigated independently and urgently.With SCNC model we developed independently,this paper simulated the potential of carbon sequestration in paddy soils in Hunan province,and the aim is to illustrate the carbon sequestration potential of paddy soils and find the countermeasures to improve the current conditions.The simulated results showed that saturated carbon storage of paddy soils ranged from 39.75-64.90t/ha under conventional fertiliza-tion,and half of the modeling plots have been saturated,while for the remaining plots,the carbon sequestration potential ranged from 3.38-4.19t/ha.The saturated carbon storage under 50% of straw incorporation was lower than the conventional fertilization,but the storage of 50% straw incorporation combined with green manure plantation treatment was higher than the conventional fertilization(increased by 10.54t/ha averagely).The saturated carbon storage with 100% straw incorporation ranged from 55.57-94.25t/ha,compared with current carbon storage,the potential in-crement was 4.15-33.46t/ha.The saturated carbon storage of 100% straw combined with green manure incorporation was 65.77% higher than that of current carbon storage.The simulation results also showed that the saturated carbon storage would hit 12t/ha under the condition of incorporating 1t/ha fresh organic material annually into paddy field of Hunan Province.Therefore,increasing the amount of organic material and planting green manure are effective measures to enhance carbon storage of paddy field.
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    Dynamic Monitoring of Vegetation Fraction by Remote Sensing in Changting County of Fujian Province
    JIANG Hong, WANG Qin-min, WANG Xiao-qin
    2006, 21 (1):  126-132,166.  doi: 10.11849/zrzyxb.2006.01.016
    Abstract ( )   PDF (294KB) ( )   Save
    Vegetation index(VI)and the transformation method of VI are two key factors in estimating vegetation fraction by Remote Sensing.Based on the common VI and the FCD(Forest Canopy Density)Model principle put forward by ITTO(International Tropical Timber Organization),VBSI vegetation index was proposed in this paper that can decrease the interferences from mountain shadows,soil background,rocks and building.It is expressed as VBSI=f(VI,BI,SI)=VI+n·BI+SI which is suitable for estimating vegetation coverage in mountainous areas.Furthermore,mixed pixel model is one of the good transformation methods from VI to vegetation fraction,which can apply to images from different phases.The expression is:fc=(S-Snon)/(Sveg-Snon).Vegetation fraction estimation in 1994-2003 was processed with ERDAS software system aimed at Chang-ting County,Fujian Province,China.The results show that(1)With VBSI,the error of vegetation fraction resulted from the area of image shadow can be decreased,and the error is 50% of that from Normalized Difference Vegetation Index(NDVI).The overall accuracy from the vegetation fraction estimation based on VBSI and mixed pixel model is more than 80%,which meets the requirements for vegetation fraction dynamic monitoring in region.(2)The coverage of high vegetation in the study area increased by 150.47km2,or an increase of 4.9% of the total land area from 1994 to 2003.This is correlative with the work of soil and water conservation in recent years in Changting County.
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    Studies on the Effect of Recreational Activities on Soil Enzyme and Microbial Activities in Zhangjiajie National Forest Park
    TAN Zhou-jin, XIAO Qi-ming, YANG Hai-jun, HE Xiao-xiang, ZHOU Hong-li
    2006, 21 (1):  133-138.  doi: 10.11849/zrzyxb.2006.01.017
    Abstract ( )   PDF (148KB) ( )   Save
    Ecological environment can be destroyed by all kinds of recreation activities,such as animal-feeding and people's touching.In order to probe into the effect of visitors' activities on soil biological properties and provide useful suggestion for ecological recreation,studies on soil microbial and enzyme activities of Zhangjiajie National Forest Park were conducted.The results showed that the soil enzyme activities in control zone were the highest,and the soil enzyme activities in buffer zone were the moderate,and the soil enzyme activities in active zone were the lowest.The soil ammonification intensities and microbial activities were:the control zone >buffer zone >active zone.The soil nitrification intensities were:the active zone>buffer zone>control zone.The microbial activities and enzyme activities in 0-5cm soil was affected prominently by recrea-tional activities.The results also showed that microbial and enzyme activities in 5-15cm soil and 15-25cm layer soil from control zone and buffer zone were not affected prominently by recrea-tional activities,but were different prominently from active zone.The ammonification intensities,cellulase activities,xylanase activities and protease activities,which were associated to the decomposition of organic matter,were mainly affected by the quantities of organ matter.The nitification intensities were mainly affected by soil physical and chemical properties,which could improve the nitrite content.The soil microbial and enzyme activities were:0-5cm>5-15cm>15-25cm.All these results showed that the soil microbial and enzyme activities in Zhangjiajie National Forest Park were destroyed,and it's necessary to take measures to protect Zhangjiajie National Forest Park from being destroyed.
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    Research on the Calculating of Surface Net Radiation in China
    LIU Xin-an, YU Gui-rui, HE Hong-lin, CAI FU, ZHU Qing-lin
    2006, 21 (1):  139-145.  doi: 10.11849/zrzyxb.2006.01.018
    Abstract ( )   PDF (331KB) ( )   Save
    Surface net radiation is an important driving force to climate change or even global change,and one of the important parameters for establishing various kinds of ecological models.However,the relatively few surface net radiation stations in China can not meet the needs of scientific research and operation.There is an urgent need to establish or screen out a method suitable for calculating surface net radiation in China.Therefore,by use of 1993-2000 radiation and related meteorology data from 50 net radiation stations in China,net radiations monthly were calculated using 5 methods,independently.By comparing the error of each method,we found that synthesis method including multi-factors constructed in this paper was proved to be a perfect method with mean relative error of 50 stations is 0.348,and <0.20 from April to September,which can be applied in the calculation of net radiation every month.In addition,methods of Chang JenHu formula and Penmann formula with the mean relative error of 50 stations is <0.64,<0.25 from April to September and the number of months <0.20 account for about half of the year can be applied in the calculation of surface net radiation during growth period.Mean relative errors induced using various methods have a temporal and spatial distribution characteristic that the values in northern China are bigger than those of the southern China and summer month(March to October) are bigger than winter month(November to January).
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    An Integrated Assessment Method of Water Quality and Quantity Related to Surface Water Resources Status
    XIA Jun, WANG Zhong-gen, YAN Dong, WANG Miao-lin
    2006, 21 (1):  146-153.  doi: 10.11849/zrzyxb.2006.01.019
    Abstract ( )   PDF (400KB) ( )   Save
    Along with social and economic development in China,the problems of integrated assessment and management of water quantity and quality are more important to sustainable development.Since 1981 of the first national comprehensive water resource assessment,the condition of water resource in China has significantly changed in both outside and internal.The main change focuses on the following two aspects:one is that water quantity has changed because of environmental impact;the other is that water quality has deteriorated due to human activities.To understand distribution of different water quality classes related to a certainty water resources quantity and their change,to develop a comprehensive integrated assessment approach of water quantity and quality is urgently needed.This paper addresses a new integrated assessment method for water quality and quantity based on surface water resources status.Major researches involve two aspects:(1)the assessment method of water quality and quantity applied to lumped or unit water system,in which the time series of both water quality and quantity are integrated in terms of different water quality classes and related water quantity increment;(2)the integrated assessment of water quality and quantity of lumped system is extended to the distributed water system in terms of hydrological system relation.The case study of Luanhe river basin in North China is given as a preliminary explanation of this methodology.It was shown that the new methods are feasible and can directly describe the space-time variation of water quality and quantity of a basin or a region.The integrated assessment results can provide the decision makers with important information on the actual amount of the clear water and non-clear water in a basin or a region and present status of their spatial distributions.This will be helpful for reasonable planning and management of water resources.
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    Research on Numerical Simulation and Evaluation of Riverside Source Field-A Case Study of Liguanpu Riverside Source Field in Shenyang City
    YI Shu-ping, CHI Bao-ming, WU Fa-wei, ZHOU Yan-zhang
    2006, 21 (1):  154-160.  doi: 10.11849/zrzyxb.2006.01.020
    Abstract ( )   PDF (426KB) ( )   Save
    Riverside source fields are widely employed in northern China owing to its stable supplying ability and pure water quality.So great attention has been paid and efforts have been devoted to the study of the rules of this kind source field by many experts and scholars.According to their studies,the rational evaluation of groundwater is the premise which guarantees the efficient source field running.But it is a complicated proceeding as to how to evaluate the groundwater rationally.Based on the hydrogelogical conditions of Liguanpu riverside source field in Shenyang city,this paper discusses the correlated problems of numerical simulation and groundwater resource evaluation in riverside source field.To further the study,the problem of optimizing groundwater withdrawal in riverside source field is also conducted.Visual MODFLOW was used in this study to support the research.Visual MODFLOW is the most popular groundwater system simulation software at present,it's fully-integrated package combining powerful analytical tools with a logical menu structure and easy-to-use graphical tools allows us to create,run,calibrate amd visualize the results of a groundwater model easily. Through the research,several conclusions are drawn as follows:(1)River is the most sensitive factor in riverside source field simulation,and the second sensitive factor is the artificial withdrawal,while hydrogelogical parameters such as K,μ and a are not as dominative as expected to the simulation model.(2)The key point in riverside source field simulation lies in the dealing of a river.To an incomplete river,it is useful to set a weak permeable layer under the riverbed in simulation.(3)The evaluation results indicate that the amount of groundwater resources is relatively stable between dry and rainy year.But the amount of groundwater does increase with the increase of pumping.It is also influenced by the distance between the pumping wells and the river,the smaller the distance is,the bigger the amount of groundwater will become.The prime reason of these characteristics is that the groundwater resource of riverside source field is mainly recharged by the corresponding river.(4)With the help of constructed groundwater flow model,it is convenient to visualize the modeling result and then adjust the pumping spots and the amount of groundwater withdrawal,so that the surface water can be fully induced to the groundwater,and thus optimizing the source field's production and eventually making it sustainable developed.The above findings are used mainly to deal with groundwater amount but have nothing to do with groundwater quality.Actually,in order to insure a riverside source field developing smoothly,such factors as water pollution,water environment and so on should be studied synthetically.
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