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    25 February 2003, Volume 18 Issue 1 Previous Issue    Next Issue
    Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Groundwater resource evaluation and development in affected zone of downstreams of the Yellow River
    SHAO Jing-li, ZHAO Yun-zhang, CUI Ya -li, YAN Zhen-peng, JIAO Hong-jun
    2003, 18 (1):  1-7.  doi: 10.11849/zrzyxb.2003.01.001
    Abstract ( )   PDF (301KB) ( )   Save
    The paper focuses on groundwater evaluation and development in the AZYRD(Af-fected Zone of the Yellow River Downstream),the section in Henan province.Since the1970s,the constant cut off of the downstream s of the Yellow River and the aggra vated pollution prob-lem have led to shortage of water supply which seriously threatened the irrigation area and cities in Henan Province along the Yellow River.Reasonable development of groundwater becomes more and more important for this region.The study area is an alluvial plain of the Yellow River,which consists of a phreatic aquifer and several confined aquifers in an area of about 104km2 .The main recharge comes from infiltration of rainfall,irrigation ditches and Yellow Riv er runoff.The main discharges are evaporation and extraction from the groundwater system.The current groundwater exploitation is about 1.152×109m3 /a from shallow and deep aquifers.A3-D groundwater flow model is built with FEFLOW to simulate and forecast the aquifer re sponses to different conditions for groundwater development.The model estimates the average recharge rate of groundwater in this area is about 2.835×10 9 m3 /a and the security yield is about 1.943×10 9 m3 /a.Nine sites are selected as prospective large-scale pumping-well-fields and the hydrogeological conditions of each site are described in brief.On condition that the prospective increased total pumping rate is0.486×10 9 m3 /a,the modeling results can indicate:(1)the maximal drawdown in the center of pumping cone is less than20m;(2)the groundwater table tends to be stable within5~10years;(3)the regional groundwater flow does not change;and(4)62.58%of the pumping rate will be recharged from the Yellow River runoff.Taking the aquifer as a huge adjustable storage for Yellow River runoff to groundwater recharge and exploitation,the surface water use amount can be increased,the water quality can be improved and the wa-ter treatment costs reduced.At the end of this paper the countermeasures for sustainable groundwater development are discussed.The research results show that the Yellow River plays an important role in surface water-groundwater ecosystems.The paper also pointed the importance of protecting the wetland s in AZYRD.
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    The geothermal resource of the northern Songliao Basin and direction for its development and utilization
    WANG Zai-jun
    2003, 18 (1):  8-12.  doi: 10.11849/zrzyxb.2003.01.003
    Abstract ( )   PDF (221KB) ( )   Save
    Rich low-to-moderate temperature geothermal resource is an important clean energy in the Songliao Basin.It can be widely used in heating,planting,aquatic breeding and sightseeing.According to synthetic interpretation and processing of varied geological,hydrogeological,inte-grated geophysical and drilling data,analysis of geothermal fields of different depths and studies of characteristics of geothermal pools,geothermal hot water energy resources in northern Songliao Basin are comprehensively evaluated in this paper.Favorable enriched stratohorizon,favorable enriched zones and favorable place for resources prospecting of geothermal resource occurred ex-tensively in endosphere of the Binbei region are generally indicated,and finally the amount of the resource is also calculated.
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    Land use/cover change of catchment and its landscape ecological effects:a case of Xitiaoxi Catchment in Zhejiang Province
    YU Xing - xiu, YANG Gui - shan, LI Heng - peng
    2003, 18 (1):  13-19.  doi: 10.11849/zrzyxb.2003.01.004
    Abstract ( )   PDF (313KB) ( )   Save
    Environmental effects of land use /cover change will become a focus in this research field in the future.Based on remote sensing images of Xitiaoxi Catchment in1985,1995and2000,land use /cover change map and land use matrix were made.This paper analyzes the tem-poral - spatial regulation of land use /cover change during the15years followed by the analysis of the corresponding relationship s between the land use /cover change and landscape ecology.The results are as follows.First,the area of arable land decreased continuously while the settlement area expanded all the time.The woodland area increased slowly after a period of going down.Second,the variation trends of landscape structure and landscape heterogeneity are patch frag-menting,shape of patch becoming regular and types of landscape simplifying.Third,the land use /cover change of Xitiaoxi Catchment has caused distinct landscape effects,such as environ-ment al quality declining,edge effects intensification,land degradation and landscape elements reducing.Finally,the paper suggests that land use manners should be improved in landscape scale so as to rehabilitate and reconstruct landscape ecosystems in Xitiaoxi Catchment.
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    Spatio-temporal distribution of land use in relation to topography in a gully catchment of the Loess Plateau,China
    QIU Yang, FU Bo-jie, WANG Jun, CHEN Li-ding
    2003, 18 (1):  20-29.  doi: 10.11849/zrzyxb.2003.01.005
    Abstract ( )   PDF (503KB) ( )   Save
    The spatio-temporal distribution of land use and its relation to several terrain indices were studied in Da nangou Catchment (3.5km2 )on the Loess Plateau,China.The previous land use map was interpreted from an aerial photo in1975(LU75)and the present land use map was compiled based on the field survey in1998(LU98).The future land-use maps were made based on three land-use scenarios in which cropland areas are restricted to slope gradients smaller than25(FA25),20(FA20)and15degree s(FA15).The25and20-degree limit scenario can be seen as short-term(before2005)and intermediate(2005~2010)scenarios,and the15-degree limit scenario can be seen as long-term scenario(after2010).A temporal sequence of land use dy-namics in the catchment consists of these five land-use maps.Two stages were recognized based on the comparison analysis on these five maps.In the first stage from LU75,LU98to FA25,the area of the wood/shrub land increases while those of the wasteland,fallow land and cropland decrease,and the orchard/cash-tree land remains the same.During the second stage consisting of the FA25,FA20and FA15,there is a gradual decrease in the cropland and fallow land and a gradual increase in the orchard/cash-tree land;the other land-use types remain the same.Conse- quently,it is found that the topographic distribution pattern of each land use type also displays the corresponding change based on the statistical analysis on the relationships between the land use type and several terrain indices.During the first stage,the wood/shrub land changes from eastwards or northward s to westwards or southwards,from the profile - concave - slope to the profile - convex - slope,from the plan-convex-slope to the concave - slope,increases in the slope gra di ent in the relative elevation.The wasteland also increases in the slope gradient,but shows opposite changes in the slope aspect,surface curvature and relative elevation as the wood/shrub land.The fallow land and cropland keep the same condition in the slope aspect,but show a stable de-creasing trend in the profile-convex-degree,plan-concave-degree,slope gradient and relative el-evation.The orchard/cash-tree land also remain s the same aspect,but shows opposite change in the surface curvature and the slope gradient,and displays a decreasing-then-increasing trend in the relative elevation.During the second stage,the wood/shrub land and the wasteland re main the same in topography.However,the cropland and the fallow land change from the eastwards or northwards to the westwards or southwards,and gradually decrease in the profile-convex-degree,plan-concave-degree,slope gradient and relative elevation.The orchard/cash tree land also de-creases in the slope gradient,while exhibits an opposite change in the other topographical in-dices as comparing to the cropland and the fallow land.In a word,it is indicated that the land use pattern of this catchment is getting more sound in the sustainable land use during the recent decades,and especially the three land-use scenarios have advantages in ecology,economy and society.
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    N03--N accumulation and its affecting factors in small watershed in gully region of Loess Plateau
    GUO Sheng-li, HAO Ming-de, DANG Ting-hui
    2003, 18 (1):  37-43.  doi: 10.11849/zrzyxb.2003.01.006
    Abstract ( )   PDF (187KB) ( )   Save
    Chemical fertilizer input was the key factor affecting soil ecological environment and land productivity in a small watershed.Wangdonggou watershed is just the type of gully region on the Loess Plateau.The monitoring of chemical fertilizer input,land use change and land pro-ductivity started in the small watershed in1984.NO3--N accumulation in soil profiles of0~300cm was determined in croplands with continuous and rotation cropping systems,apple yard with7-and15-years of apple trees as well as fallow land in the small watershed.Fertilizer input,NO3--N accumulation,and land use structure were analyzed in the small watershed.The results showed that chemical fertilizer led to significant increase in land productivity and decrease in the area of cropland.Chemical fertilizer input was an important driver to land use structure change,the area of apple yard land increased significantly from1984to1995.Changes in land use structure further affected input of chemical fertilizer into the small watershed.NO3--N accu-mulation in soil depth of100~200cm has been significantly produced in cropland and apple yard land under current conventional fertilization practices.NO3--N accumulation in apple yard land was greater than that in cropland.NO3--N accumulation in continuous cropping systems was greater than that in rotational cropping systems.NO3--N accumulation was obviously related to fertilizer input,fertilizer uptake by crops,and soil moisture change in the small watershed.
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    An analysis on eco-economy system health in Zhifanggou Small Watershed of Ansai on Loess Hilly-Gullied Region
    LIU Guo-bin, HU Wei-yin, XU Ming-xiang
    2003, 18 (1):  44-49.  doi: 10.11849/zrzyxb.2003.01.007
    Abstract ( )   PDF (233KB) ( )   Save
    The aim of establishing a healthy ecosystem is to rehabilitate the degenerated ecosys-tem and turn the landscapes of the Loess Plateau green.The Chinese Government has promoted integrated watershed management measures for years to control soil erosion and improve the eco-environmental conditions in a hilly-gullied region of the Loess Plateau.However,there is still no proper method for assessing the health of the ecosystem.This paper,taking Zhifanggou Water-shed in Ansai County as an example,by using the hierarchical approach and selecting evalua-tion indicators such as forest and grass coverage,area of fundamental cropland,soil anti-scoura-bility,soil organic matter content,output/input ratio,per unit area crop yield,per capita net in-comes and benefit of soil erosion control by comprehensive management,the improvement pro-cess in ecosystem rehabilitation of the watershed was analyzed.The result showed that after about 20years of soil conservation practice,the ecosystem health index of the watershed has im-proved from0.178in1985to0.707in1999after experiencing initial restoration,stable im-provement and benign circulation period.This research introduced for the first time the new in-dicators of soil anti-scourability,soil organic matter content and gave the different weight value of indicators in health index calculation in the rehabilitation process.
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    The impacts of the Laxiwa Dam on regional eco-environment
    GUO Qiao-yu, LI Chun-hui, CUI Bao-shan, YANG Zhi -feng
    2003, 18 (1):  50-57.  doi: 10.11849/zrzyxb.2003.01.008
    Abstract ( )   PDF (676KB) ( )   Save
    Although hydroelectric stations can generate great economic benefit and create de-velopment opportunities,some irreversible changes in eco-environmental system can also be caused by hydroelectric stations.Because non-pollution Ecological Impact Assessment (EcIA)in Environmental Impact Assessment (EIA)of hydroelectric stations has just initiated for a short period of time,the methods of EcIA of hydroelectric stations are still in mature.Laxiwa hy-droelectric station is an important part of North Channel of“Transmit Electricity from West to East”,at the same time,the eco - environment around the station is relatively sensitive and fri-able.Based on the illumination of the present eco-environmental status of the area around the station,the biological productivity of vegetation and the biomass have been measured and the landscape spatial patterns have been analyzed.According to the primary design of the Laxiwa hydroelectric station,the impacts on biological production of vegetation,biomass,landscape pat-terns and biodiversity were evaluated.The results show that the eco-environmental impacts of the Laxiwa hydroelectric station are quite acceptable.Finally some corresponding countermeasures are presented in the study.
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    The experimental research on slight and moderate water stress effcts on increasing yield and saving water mechanism of winter wheat
    HUO Zhi-guo, LI Shi-kui , BAI Yue-ming, WEN Min, WANG Su-yan, HU Yan-long
    2003, 18 (1):  58-66.  doi: 10.11849/zrzyxb.2003.01.009
    Abstract ( )   PDF (369KB) ( )   Save
    Using large movable rainshelters to keep off precipitation,the field experiments on the water stress treatments of different soil moistures and duration of winter wheat are conducted under controlled irrigation conditions.The soil relative moistures for different treatments were controlled at40%~50%,45%~50%,50%~55%,50%~60%,55%~60%,60%~70%and CK(80%),and the duration of water stress was5,10and15days respectively.The result indicated that:for the slight and moderate water stress treatment with soil moisture being50%~70%,the efficiency of increasing yield and saving water of winter wheat was significant;in which the yield increased by3%~17%for treatment with55%~60%and50%~60%,the average yield of two years increased by7.4%;the yield increased by1%~23%for treatment with55%~60%and60%~70%,the average yield of two years increased by6.3%.For different treatments,water consumption of winter wheat decreased significantly,than that of CK,the average water consump-tion of two years for treatments with40%~50%,50%~60%and55%~70%decreased by48.5%,34.1%and28.2%respectively,more than those of CK.Under the slight and moderate water stress treatments,the realization of winter wheat increasing yield and saving water mechanism was mainly using water stress effects to accelerate:(1)the water seeking function of roots,and water use efficiency of roots at depth of100to200cm improved markedly;(2)the optimiza-tion of yield factors,weight of thousand grains and grains per spike increased,unfertilized spike and retrogressive spike decreased;(3)the stomal resistance of leaves enlarged,tran spiration rate decreased and photosynthetic rate increased after rewatering.The best time to use the water stress effects of winter wheat was from regreening to enlongation,when it is favorable for stable yields or increasing yields of winter wheat.
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    A study on landscape sustainability for agri-pastural ecotone in Horqin Sandy Land
    CHANG Xue-li, LU Chun-xia, GAO Yu-bao
    2003, 18 (1):  67-74.  doi: 10.11849/zrzyxb.2003.01.010
    Abstract ( )   PDF (553KB) ( )   Save
    Aimed at measuring the change trend and characters of landscape pattern in the past forty years,this paper analyzed the landscape sustainability of agri-pastural ectone in Horqin Sandy Land by using Landsat TM images data.The results showed that the sustainability index of landscape diversity increases some 1.038(±0.033)and the sustainability index of landscape dominance decrease about 0.873(±0.112)on different temporal scales.The data suggested that the fixed sand-dune landscape as the main part in1958have changed into the mosaic landscape pattern consisting of shift sand-dunes,semi-fixed sand-dunes,fixed sand-dunes and cropland in1998.Because of the influence of agricultural and the grazing activities on the landscape,the sustainability of landscape patterns in spatial scale became more complicated and the sustain-ability of fractal dimensions was1.008,meanwhile the juxtaposition decreased and the modified fractal dimension was0.953.The analysis of different time scales indicated that the sustainabili-ty of patch areas of mobile sand-dunes and semi-fixed sand-dunes increased and that of fixed sand-dunes and cropland decreased.In terms of patch pattern,the sustainability of semi-fixed sand-dunes increased more obviously and its index reached1.038(±0.087)while the sustainabili-ty of fixed sand-dunes decreased most obviously and its index was0.806(±0.032).The impacts of agricultural and grazing activities on sustainability of modified fractal dimensions appeared to decline,which suggested a decrease of the patches juxtaposition in the past years in Horqin re-gion.
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    Landscape patterns and dynamics in the upper reaches of the Dadu River
    BAI Wan-qi, ZHANG Yi-li, BAO Wei-kai
    2003, 18 (1):  75-80.  doi: 10.11849/zrzyxb.2003.01.011
    Abstract ( )   PDF (132KB) ( )   Save
    Based on satellite imagery,this paper has analyzed the landscape patterns and dynamics in the upper reaches of the Dadu River,which consists of3counties of Jinchuan,Rangtang and Maerkang,covering an area of18665km2 .The results show a decreasing landscape fragmentation process,increased landscape diversity and irregularity of patch shape between1995and2000.The whole region is characterized by grassland being matrice and changes in forest land.Within5years between1995and2000,forested land decreased53687ha,most of which were converted to shrub and sparse woodland.The decreased density and increased regu larity of forest patches indicate that the decreased forests were due to a planned logging taken by local forestry enterprises.Meanwhile,a decreased cultivated land indicates that the governmental policy of“returning farmland to forest land and grassland”has taking effects.
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    On adjustment of the rural energy development policy in China
    ZHAI Fu-dong
    2003, 18 (1):  81-86.  doi: 10.11849/zrzyxb.2003.01.012
    Abstract ( )   PDF (205KB) ( )   Save
    The policy for rural energy development in China is“to suit measures to local condi-tions with multienergy complementing each other and comprehensive utilization to strive for ben-efit”.It was posed in the background of solving the energy crisis related to less-developed econo-my.But at present,the supply and demand of rural energy has changed from planned economy to market economy and from shortage of traditional biological energy to coal energy surplus in market.So the old policy could no longer suit to the situation of new rural energy sustainable development.In order to guide further sustainable development strategy of rural energy,the ar-ticle poses the new development policy—“Suit measures to local conditions,build energy e-cosystems,market preferential treatment and strive for comprehensive benefit”.The paper pre-sents a new theory of sustainable development of integrating biological secondary energy with commodity energy,makes an exposition of argument of the new policy and poses policy.
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    Temporal characteristics of exchange and transit of water bodies
    LIU Lü-liu, YANG Zhi-feng, SHEN Zhen-yao
    2003, 18 (1):  87-93.  doi: 10.11849/zrzyxb.2003.01.013
    Abstract ( )   PDF (313KB) ( )   Save
    Exchange and transit of water and material in natural reservoirs and between the reservoirs and their environments occur all the time.The characteristics of different reservoirs vary.In the paper,some concepts to describe the temporal characteristics of these reservoirs are analyzed.The similarities and dissmilarities of different concepts are compared.The calculations of replacement period and re newal time are introduced especially and their relationship is ana-lyzed by formula(6)and figure1.On the basis of predecessors' studies,the relationships among replacement period,average transit time,average age and average residence time are analyzed when the locations of inlet and outlet of water bodies are different.As an application,the re-placement periods for middle and lower reaches of the Yellow River are computed.The change trends of the monthly replacement periods are analyzed.The results show that during less runoff period,the values for replace ment period are larger than values during more runoff period.The relationship between replacement period and flow are researched also.Negative correlation be-tween them is found.
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    Study on a pricing approach to environmental value of forest resources—improved Timber Demand Curve Amend Method
    CAO Jian-hua, YANG Qiu-lin
    2003, 18 (1):  94-98.  doi: 10.11849/zrzyxb.2003.01.014
    Abstract ( )   PDF (194KB) ( )   Save
    Many methods are used to evaluate environmental value of forest resources in the world.A new approach,i.e.,Timber Demand Curve Amend Method(TDCAM),was introduced by the authors.In this paper,the objective of the research is to study farther and improve TDCAM,so as to make the method more scientific and rational in evaluating environmental value of for-est resources.The approach of improvement of TDCAM is undertaken in light with the following procedure,namely,the optimal allocation of forest resources is made by equal marginal utility ac-cording to the principle of economics,the total environmental value of forest resources is inte-grated into environmental marginal utility value,and unit environmental value of forest resources is priced by average value transferred from direct marginal utility value according to the princi-ple of public goods.The method is used in a case of Jiangxi province to evaluate environmental value of forest resources.The result is that in a given condition the total environmental value of forest resources is288.7×10 8 yuan,and the unit environmental value of forest resources is1145×10 8 yuan/m3 in Jiangxi province.The improved method is better than the original,and is of logi-cality and convenience.It can reduce the errors when total environmental value of forest re-sources is calculated by the method.
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    A study on rainfall chemistry of artificial forests in red earth hilly area
    CAI Yu-lin, LI Fei, LI Jia-yong, CHEN Yong-rui , LI Hai-tao, ZHANG Hong-zhi
    2003, 18 (1):  99-104.  doi: 10.11849/zrzyxb.2003.01.015
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    This article interprets how rainfall influences the element cycling of artificial forests.Forest hydrological effect of three main artificial forests in red earth hilly area was studied with regard to precipitation chemistry based on complete data from field experiments at Qianyanzhou Ecological Station of CAS.The concentrations and amount of chemical elements including K,Ca ,Na ,Mg ,S and P in stem flow and through fall were studied in forests of sub-tropical zone,mean-while comparisons were made among three main tree species.Concentrations of six chemical el-ements of stem flow and through fall were analyzed.The results showed that different tree species own different exchange characteristics,and Mg ,K and Ca in the three tree species were easily to be leached,but P and Na were absorbed apparently.
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    A case study on wetland restoration from paddy fields to fishing pools in the waterlogged area of South ern China
    TIAN Xiao-hai, HUANG Yong-ping, JIN Wei-bin, HUANG Zhi-min, LI Bi-hua, LIU Wei
    2003, 18 (1):  105-111.  doi: 10.11849/zrzyxb.2003.01.016
    Abstract ( )   PDF (465KB) ( )   Save
    Taking a typical farming micro-zone from the reclamation of a small lake in the waterlogged area in Jianghan Plain as an example,we discussed the necessity and the working plan for the wetland restoration from paddy fields to fishing pools.An investigation to the soil and the rice growth showed that the soil and the landforms retained some properties of the influences from the lake when the land reclamation was inadequately done in drainage and land leveling.The soil at the lower part of the original lake was featured by severe gleying.The yield of rice growing there decreased by16%~26.8%in contrast to the nearby regions with normal soil.Apart from the lower yield,the rice was often subjected to flooding.By using the model of Quantification TheoryⅠ,a plan to identify the specific sites and area of the land converting from paddy fields to fishing pools was fulfilled.The implementation of the plan showed that the total fishing area restored from the paddy fields increased9times in comparison to that of the year in1996when the project started5years ago.The benefits of fishing was5~10times more than that of rice growing.The drainage pressure in the farming microzone was mitigated by fishing in the summer and winter at the same time.
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    The laws of the information entropy values of land use composition
    TAN Yong-zhong, WU Ci-fang
    2003, 18 (1):  112-117.  doi: 10.11849/zrzyxb.2003.01.017
    Abstract ( )   PDF (242KB) ( )   Save
    Land use system is a complicated and macro system with dissipative structure.It has orderly characteristics of function and structure.The order degree of land use system is applied to express information entropy values and the applications in the regulation of the land use struc-ture in a region are discussed in this paper.The information entropy values of land use structure in different periods of time and regions sare calculated,and the laws and causes are analysed.Firstly,the information entropy values of land use structure of Lishui city in Zhejiang Province and the province itself covering the peri-od of1990to1999are calculated.The results show that the information entropy values in1990are the lowest and then rise.They fall after they arrive at the highest values.This indicates that the land use systems go through a course from order to disorder and returning to order.Secondly,the information entropy values of land use structure of the whole country and the East region,the Central region,the West region,Zhejiang Province and the cities of the province,Hangzhou city and the five counties under the jurisdiction of the city are calculated.The information en-tropy values decrease progressively from the coastal area to inland.This indicates that the order of land use system increases progressively from the coastal area to inland.The applications of the information entropy values of the land use structure are discussed in the paper.The information entropy values are of guiding significance to the regulation of the land use structure in a region as they can reflect the dynamic change and transformation degree of land use types in a region in a certain period of time.However,the point is how to set remains to be researched with the optimum information entropy value of the land use structure in differ-ent region s.
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    The impact of human activities on ecosystem services
    ZHENG Hua, OUYANG Zhi-yun, ZHAO Tong-qian, LI Zhen-xin, XU Wei-hua
    2003, 18 (1):  118-126.  doi: 10.11849/zrzyxb.2003.01.018
    Abstract ( )   PDF (327KB) ( )   Save
    Ecosystem services are the foundation of man's sustainable development.But when human take advantages of many kinds of ecosystem services in providing natural resources and living environment,they also affected ecosystem services intensively.Although a part of human activities are helpful to stabilize and improve ecosystem services,more of them result in a series of eco-environmental crises and disasters that endanger man's survival and development.The damage of ecosystem services due to anthropogenic effects and its consequence are increasingly becoming outstanding problems in the world.The impact of human activities on ecosystem ser-vices has received much attention of human society at present.It is urgent to make clear the de-gree and ecological mechanism that human activities impact ecosystem services.The patterns and mechanisms and changing trend of ecosystem services affected by human activities were ex-plored in this paper.The impacts of human activities on ecosystem services include negative effects and positive effects.The former weaken ecosystem services through changing habitat and changing ecosystem structure and changing biogeochemical cycle.The main patterns include land reclamation,ur-banization,industrialization,grazing,hunting,international trade,agriculture and so on.The lat-ter play a significant role in improving eco-environment condition.The study of these passive factors,such as ecosystem management,ecological engineering,ecological restoration and reha-bilitation,ecological planning and evaluation,is also undertaking in a more and more deep-going way and has become the hot spot of ecological research.Although many researchers have carried out substantial studies on the impact of human ac-tivities on ecosystem services,much work still need to be conducted in the formation mechanism of ecosystem services,the threshold of ecosystems in bearing the human interference and the simulation and predication of human impacting ecosystem services.These problems were posed in this paper.
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