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    Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    MA Jin-yu, LIU Jing-miao, LI Shi-kui, LIANG Hong, JIANG Chao-yang, WANG Bing-zhong
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    The photosynthetic active radiation(QPAR)is an important parameter in biology,ecology and agriculture,but in routine meteorological data no QPAR is observed and the observation data are also relatively less.So,the previous calculation of QPAR often uses experiential climatology method.In this paper,the characteristics of photosynthetic active radiation are analyzed by using radiation data from Gucheng Experimental Station.The results show that the ratio of photosynthetic active radiation to global radiation(η PAR)presents an approximate campanulas distribution with 60% ofη PAR ranging between 0.35-0.45.The tendency of daily variation forη PAR in sunny day presents a single-peak pattern that theη PAR is high at noon and low in morning and evening.At the same time,in cloudy day,the daily variation of theη PAR fluctuates while the cloud cover changes,and theη PAR in cloudy day is higher than that in sunny day.In addition,the yearly variation ofη PAR presents a tendency that it is lower in winter and spring but higher in summer and autumn.QPAR and Q show an evident tendency of single-peak patterns.The mean annual value ofη PAR is 0.40 and 0.41 during growth period.The relationships of QPAR and Q are as follows: for a whole year,QPAR=0.40Q;and for a growth period,QPAR=0.41Q.Generally,the result is similar to some measurement results in China.The potentiality of photosynthetic production is evaluated by using theη PAR in this paper.The results shows that the potentiality of photosynthetic production evaluated previously by usingηPAR(0.47~0.50) is obviously higher than the measurement results.In addition,the causes of the variation of the photosynthetic active radiation are related to the solar altitude,cloud cover,water vapor and dust in atmosphere.In conclusion,some causes are very complicated,so further studies are needed.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    XIE Xian-qun, WANG Ling
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    The authors estimated the changes of potential evaporation in northern China over the past 50 years (1950-2000) by using the Penman-Monteith model and also analyzed the observation pan evaporation data in the same regions in this paper.The results showed that the potential evaporation and pan evaporation amount had a same decreasing tendency in recent 50 years.The main reasons for the decrease of potential evaporation and pan evaporation amount were due to the decrease of sunshine percentage and wind speed and increase of air humidity during this period of time.From the viewpoint of the energy,the solar radiation reduction was also one of the main reasons for evaporation decrease.The present research indicated that the air humidity increase and the increase in energy resources consumption owing to anthropogenic activities were the two important factors affecting total solar radiation reduction.According to the estimation by Penman-Monteith model the decreased amount of potential evaporation induced by reduction of solar radiation reaching the earths surface accounted for 78% of the total amount of evaporation decreased.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    LI Yue, JIA Shao-feng
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    There are three kinds of water resources allocation model,government allocation,market allocation and quasi-market allocation.Within the process of institutional reformation of water rights,the institution of water resources allocation is changing from government allocation to market allocation.In neoinstitutional economics,transaction cost theory and theory of rent dissipation can offer gist for the design and choice of new water allocation system.Because of the different systems of the water rights allocation,there are various transaction costs,better institution will get more social net rent after deducting transaction costs.At the present,the most exigent task for Chinese water resources management is to define the public and private rights of water resources scientifically,and then to transit from complete control of government to market system.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    GU Xiao-kun, CHEN Bai-Ming, DAI Bing
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    Following the Chinese government’s increasing attention to the three dimensional rural issues and building a new socialist countryside,land consolidation of rural habitat has been turned into a hot issue.Now the key is,compared with a great lot arable land consolidation projects completed in just a few years,few land consolidation projects of rural habitat are successful. Different from most other parts of China,683 of 1146 administrative villages had successfully completed the land consolidation projects of rural habitat in 2001-2005 in Shengzhou,Zhejiang.So,it’s necessary to analyze the driving force and model of these projects and recommend the successful experience to the similarity regions in China. The rural habitat area reduced after a process of expansion from 1996 to 2004,and some differences in features of land space are analyzd with ARCGIS and fragstats3.0.Land-use policy and rural economic and social factors are the driving forces of land consolidation of rural habitat. Policy driving factors of land consolidation in rural habitat include the policy of balance of arable land and policy of regional transfer of arable land occupied index produced in land consolidation of rural habitat.Economic and social driving forces which are calculated with Principal Component Analysis by DPS(Data Processing System)include the city’s economic and social development,urbanization and rural economic and social development. The consolidation model of Shengzhou is characterized by projects which are invested and practiced by three main groups,including relevant government departments(for land consolidation and reclamation),the village collective economic organizations,and villagers.The two key questions are the finances and the voluntary support of villagers,which are restricted by rural economic and social development,and land use policy. From one typical project of Chongren we can see that,the land-use pattern was optimized, 66.67% of new farmland was produced,the average fund balance reached 228%,intensive land-use increased by 176%,agricultural employment increased 20% and land pensions 10%.Although farming radius becomes less than 500m,there are no significant change in urbanization of the rural population and traditional culture.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WANG Jin-song, GUO Jiang-yong, QING Ji-zu
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    A kind of K drought index and its criterion are made by using spring precipitation and evaporation data of 140 stations in Northwest China from 1971-2000.At the same time,the comparison is done among the defined K drought index,improved Palmer drought index and precipitation anomaly percent. From 2001 to 2005,the verifications of K drought index have done with the independent precipitation and evaporation data,which were not involved in making the drought criterion at four representative stations,namely Urumqi,Yushu,Lanzhou and Xifeng,respectively.The results show that the heavy drought areas are located in south Xinjiang,west Gansu and west Qinghai,the moderate drought areas are located in southern part of north Xinjiang,north and east Gansu,north Ningxia,southeast Qinghai and north Shaanxi,and the light drought areas are located in west Xinjiang,south Gansu,west Qinghai and east Shaanxi.The K drought index has a better function of drought monitoring,and the improved Palmer drought severity index has better monitoring effect in arid area,but it has some limitations to monitor drought in plateau area,semi-arid and sub-humid areas.Precipitation anomaly percent has good monitoring effect for light and heavy drought,but it has bad monitoring effect for moderate drought.It is verified again from 2001 to 2005 that the improved Palmer drought severity index has some limitations to monitor drought in Northwest China,but the K drought index has better monitoring effect in Northwest China.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    GUAN Zi-ling
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    This paper,using the improved"economic index" for the first time,chooses seven assessment indicators for generally characterizing the economic level of a thrifty society.It then defines the indicators weight by principal component analysis,calculates and analyses in an ordering way the economic indexes of the 31 provinces,autonomous regions and municipalities of China in 2005. Finally,by means of Arcview 3.3 software two diagrams are made:one is space distribution of the resources economic indexes of China,and the other shows the relationship between economic indexes and per-capita GDP in the provinces and autonomous regions of China.The results show that space difference of China’s resources economic indexes is significant,as a whole,the eastern part is more economical than the western,and the central is transitional except for Shanxi Province;and about two-thirds of the provinces’s economic level is lower than the nation’s average,mostly in the western part;besides,the higher the economic development level in a province,the better the performance of its resources and environment.The studies reveal that there are different economic levels of constructing a thrifty society and different resources use efficiencies in different provinces and autonomous regions of China.At the same time,it also can provide a basis for promoting balanced development among different regions and the socioeconomic sustainable development.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    YIN Le, NI Jin-ren
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    An indicator system was proposed for dynamic assessment of soil anti-erodibility by water (SAEW).A typical small watershed,Zhifanggou in Loess Hilly-gully region,was selected as a study area where dynamic change process of the SAEW was assessed in the period of 1938 to 2000. Relative SAEW index (RSAEWI) together with the concepts of ecosystem health and carrying ability were introduced to evaluate the variation degree of the SAEW,taking the SAEW in 1938 as a benchmark representing the natural conditions.Moreover,the change of the ecosystem health states and resilience characteristics was analyzed.The results showed the SAEW of Zhifanggou Watershed was in the natural state in 1938,since then,because of the human actives’ interferences,the SAEW became lower with high velocity.The trend changed in 1961,when the SAEW reached its lowest level.The SAEW began to recover around 1963,but the recovery speed was relatively slow,and the SAEW failed to meet its natural level after 39 years’ recovery.The SAEW was an important aspect of ecosystem,with the conception of ecosystem health and carrying ability,the SAEW index was graded according to the different health states of ecosystem.In the aspect of SAEW,the ecosystem of Zhifanggou watershed was in a health state during the period of 1938 to 1947,then turned to be subhealth.The health state became better since 1963,and became healthy again in 1990.Based on the analysis of the land-use structure and the recovery characteristics,the curves of R-SAEWI and relative land use structure index (R-SI) revealed the responding relationship beteew SAEWI and land use structure,which proved that the human activity had strong impacts on SAEW.Meanwhile,the time lag appeared in the response curve was discussed.The assessment results agree quite well with those reported by previous investigators,which showed that the method presented in this paper is of primary use for the SAEW prediction and the practice of soil and water conservation.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    QIAN Jun-ping, LI Xia, AI Bin, Anthony Gar-On Yeh, CHEN Xiao-Yue, LIU Kai, ZHUO Li
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    Remote sensing is one of the most efficient ways of land-use/land-cover monitoring.So far most land-use data could only be updated every one or two years by satellite.Recently,short-term land-use/land-cover change monitoring is gaining increasingly concern in urban planning, land management and ecological science.While comparing to long-term change detection,short-term land-use/land-cover change detection is relatively more difficult.In short-term change detection,both the land-surface reversible seasonal change and the in-reversible land-use change,such as man-made changes are remarkable in difference scenes of images.Hence any feasible short-term change detection method should be able to tell the difference between seasonal land-cover change and land-use change.In this paper,a time-series-case-base-reasoning (TSCBR) method was proposed to trace the dynamic variation of local land-use/land-cover change,which can extend the CBR from temporal reuse to spatial reuse.And 15 scenes of Radarsat-1 fine images were taken for trail in the Pearl River Delta,south of China.Firstly,stratified sampling was carried out and case parcels of different classes were selected.Secondly,time series image segmentation was performed on the 15 scenes of time-series images and backscatters and texture characteristic were extracted basing on the segmented objects.Then objects-based similarity comparison was performed between cases parcels and other parcels in the study area.k-NN algorithm was adopted and the most of the matched case types were assigned to the parcel compared.For each parcel a time series match matrix was generated and the parcel whose matched-case type varied from one type to another was defined as changed parcel.Finally,field collected data was used for validation.The classification error of TSCBR was about 20.5% and change detection error was about 11.8%.In all the classes,vegetable plot gains the maximum classification error (29.8%) and change detection error(15.2%). The next is development area(classification error 24.9%,change detection error 14.9%) and orchard(classification error 27.5%,change detection error 14.8%).Big error in vegetable plot owes mainly to its various plant pattern and fractal distribution in the study area.Besides,river gains the minimum classification error(7.9%) and change detection error(8.9%).In general,TSCBR proposed an applicable short-term changes detection method with only a small quantity of known cases. Comparing to traditional static case-base reasoning,TSCBR could trace the dynamic variation of land parcels in backscattering and image texture.This enable the real-time observation of short-term land-use change in fast developed area.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    FENG Zhi-ming, YANG Yan-zhao, ZHANG Jing, WANG Xiu-fen
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    Based on the situation of food security and sustainable agricultural development,this research attempts to study systematically issues of potential grain productivity and potential yield increase in China by applying theoretical models (Agro-ecological Zone,AEZ) at 1km×1km grid and county levels with geographic information system(GIS) technologies.The results shows that in general the potential grain productivity tends to be higher in Southeast than in Northwest China,and the multi-years average potential photosynthesis productivity,phototemperature productivity,precipitation productivity and land productivity is 71.73t/hm2·a,19.71t/hm2·a,15.86t/hm2·a and 11.81t/hm2·a at 1km×1km grid level in China;the potential productivity at county level shows the same distribution model as that at grid level,and the average potential phototemperature productivity,precipitation productivity,water resources productivity and land resources productivity is 16.82t/hm2·a,13.74t/hm2·a,15.27t/hm2·a and 11.07t/hm2·a;the index of potential yield increase of phototemperature,water resources and land resources is 0.55,0.50 and 0.32,which shows that the present grain productivity has more than 1 double,1 double and 1/3 increase space according to the phototemperature potential productivity,water resources potential productivity and land resource potential productivity;and the development of grain production varies significantly among the counties studied,and the development of grain production in Inner Mongolia and Losses Plateau has a big space,while in Norhtwest China,Huang-Huai-Hai Plain and Sichuan Basin the increase of grain production has a small space.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    YANG Li, LIU Ning, DAI Ming-zhong, LU Gen-fa
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    One cause of the increasingly serious environment problem in China is residents’ improving living consumption,which not only brings waste water,garbage and other environmental negative effects directly,but also is the ultimate causation of eco-environmental stress as the one main part and the fundamental drive of social reproduction.Governments of every level in China are always setting it as a development goal to improve people’s standard of living,which may make us in a dilemma as the progress of heightening living standard probably means to occupy more resources and to worsen environment.More and more researchers pay attention to the environmental effects and resources consumption of residents’ living. In this paper,the authors research the eco-environmental stresses from urban and rural residents’ living consumption of Harbin city by applying the theory and method of ecological footprint(EF), and analyze the differences of the consumption structure and its eco-environmental effects between urban and rural residents’.The aim is to show the scientific argument for establishing a sustainable consumption style and modulating the urbanization progress. The concept of EF was advanced by the two Canadan ecological economists,William Rees and Wackernagel in 1991,and has been applied extensively to assess sustainable development,to evaluate regional ecological asset,to analyze residents’ consumption and so on.The authors calculate and analyse the EF of 6 items of living consumption (including food,clothes and other commodity,energy,water resource,dwelling house and waste) of Harbin city between 1985 and 2003.Because of the differences existing between urban and rural areas in living standard and consumption structure, the EFs of urban and rural residents are calculated respectively. The results show that the EF rose from 0.620 ha/person to 1.268 ha/person from 1985 to 2003,and exceeded the ecological capacity (1.102 ha) in 1998.The urban residents’ EF and that of rural residents’ were quite different.Urban EF was always more than rural EF and the increase rate of urban EF is more than that of rural EF.From 1985 to 2003, urban per capita EF rose from 0.765 ha to 1.614 ha with a yearly increase rate of 4.23%,while rural EF rose from 0.572 ha to 0.953 ha with a yearly increase rate of 2.88%.Each item of urban EFs was greater than rural respectively.For example,the order of urban EF in 2003 was:food(1.054)> commodity (0.201)>energy(0.200)> waste(0.134)> dwelling house(0.020)> water resource(0.006),and the order of rural EF was:food(0.711)> commodity(0.112)> waste(0.071)> energy(0.051) > dwelling house(0.006)> water resource(0.001).Urban and rural food EFs were the greatest in their EF structures,but the tendency of their percentages declined from 1985 to 2003 because the EFs ofcommodity and waste increased more rapidly.For the close relation with the food,the arable land was also increasing and the closest in the land structure.Urban per capita arable land increased from 0.544 ha to 0.947 ha,and that of rural from 0.467 ha to 0.700 ha. This research also reveals that the regional eco-environmental stress would increase with the growing quantity of per capita substantial consumption and the increasing population transferred from country to town,which would change the consumption style and lose the channel of natural treatment and disposal of waste.So we must control the progress of urbanization and make great efforts to establish a sustainable consumption style,which is characterized by moderation and environmental friendliness.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    YE Hao, PU Li-jie
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    As one of the Chinese economic swift growth and impacted areas,Jiangsus province’s arable land area has decreased rapidly with social and economic development in recent years.The relation between land use change and economic growth is more obvious and typical throughout the country.This paper reveals the cointegration and causality of arable land area,economic growth and urbanization level from 1981 to 2004 according to the data of long series statistics of arable land area,GDP and urbanization level.The results show that arable land area,GDP and urbanization level are nonsteady time series,hence it is not rigorous to make regression analysis directly to them.There isn’t a long-term cointegration between arable land area change and economic growth.Arable land area’s rapid decrease may be induced by some short-term causation in the exceptional period.So,we can’t think that this trend is reasonable and sustainable later.Economic growth and urbanization level are the causation of arable land area change,but arable land area change isn’t the causation of economic growth and urbanization level.There is one-directional causality between the Jiangsu province’s GDP and arable land area,and arable land area decrease isn’t the causation of economic growth.According to Jiangsu province’s land use data,the arable land area decreased 260.48 thousand ha and 184.73 thousand ha of arable land were converted into construction land from 1996 to 2004.The arable land area that has been converted into construction land occupied 71% of the decreased arable land.This shows that actual land use pattern is reasonless.So,how to slow down the arable land decrease speed by adjusting economic structure,how to use little land as much as possible to sustain economic development by improving land use efficiency and how to perfect land provision system to meet the demand of economic growth are very pressing strategic issues.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    YIN Jun, XIE Jun-qi, WANG Li, ZHANG Gui-jun, GUO Qing-shi
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    This paper puts forward the index system of evaluation of land intensive use in metropolis by using RS date which is the primary data source in this system.By analyzing the characteristics of the remote sensing image (IKONOS),we can therefore interpret the types of urban land use according to the method of RS interpretation.We compared the two methods of integrated evaluation method and artificial neural network (ANN) method by using the index information of potential evaluation of urban land intensive use and found ANN is a feasible evaluation method,which can reflect the complex nonlinear relationship between independent variables and dependent variables.We built the method system to evaluate urban land intensive use based on RS and ANN.This model is applied to evaluate the land intensive use in Shijiazhuang.Practice has proved this kind of evaluation method may be more time-effective,more practicable,more convenient and the appraisal result is more objective.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    LIU Xiao-ran, LI Guo-ping, FAN Guang-zhou, GHENG Bing-yan, LI Hong-quan
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    On the basis of the monthly precipitation data for the period 1961-2000 collected from 96 observational stations in Southwest China (SWC),the methods of principal component analysis, rotated principal component analysis,and wavelet analysis are used to analyze the spatial and temporal characteristics of annual precipitation resource.The main results show that the yearly precipitation resource in the western part of SWC increased in these 40 years,and the yearly precipitation resource decreased in most eastern areas except Chongqing.The spatial characteristics of precipitation resource in Southwest China are complex with anomaly differencebetween the south and the west,and in the east and the west of SWC.The precipitation resource abnormal area can be divided into eight subregions:southern Yunnan,western Sichuan Plateau, eastern Yunnan and western Guizhou,eastern part of Sichuan Basin,western part of Sichuan Basin,western Yunnan,northeastern Guizhou and southeastern Chongqing,and Liangshan mountain. The precipitation in the plateau of western part of SWC had a dry-wet-dry process and an increasing trend in 1990s.The precipitation in eastern part of Sichuan Basin had a wet-dry-wet process.The precipitation appeared a decreasing trend in western part of Sichuan Basin and entire southeastern part of SWC.Except the remarkable period of 14 years in the regions of western Sichuan Plateau,southern Yunnan,eastern Yunnan and western Guizhou,the main periodic and annual change laws of other regions are different from each other.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    HUANG Gao-bao, QIN Shu-hao
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    As oasis area in Hexi corridor has more and more serious problems of wind erosion,shortage of water and heavy evapotranspiration,evapotranspiration characteristics of different tillage methods of winter wheat field and their influence factors were studied in 2005-2006. Results showed that:no-tillage with stubble retention(NTS)and no-tillage with stubble standing (NTSS) could reduce markedly soil evaporation and improve water use efficiency(WUE),and NTS was even better than NTSS.However,evaporation and transpiration under treatments with stubble cover(NTS and NTSS) was even higher than non-covered treatments(T,TIS and NT) when soil water content at layer of 0-10cm of non-covered treatments was lower than 13%.Normally,evaporation under treatments of TIS and NT was higher than covered treatments,and evaporation under T was strong in morning.Transpiration rate was,in a most significant state,positively,related with Tl,Gs and Ta and negatively related with RH.Evaporation was,in a most significant state,positively related with ST and negatively related with RH.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    CAO Fei-feng, YUAN Wei, LOU Zhang-hua
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    With Fuyang Area as a case,the main component analysis method is adopted to find out the main driving factor that influences the water resources nature supporting-ability by reducing the dimension of the related indexes influencing the water resources nature supporting-ability in the high dimensional variant space in the premise that the data information is the least.Then,based on the linear relationship between the amount of the water resources(following variant)and its driving force(self-reliant variant) during a certain period in Fuyang area,this paper makes use of the statistical documents to establish a multiple linear regression model of the driving factor of the water resources nature supporting-ability changes.It lastly draws the conclusion that the indexes that influence greatly the water resources nature supporting-ability in Fuyang area are the available water resources amount,surface water resources,groundwater resources,remaining exploitation degree of the water resources and the chemical oxygen demanding amount.These indexes constitute the driving factors of the water resources nature supporting-ability.It can be seen from the calculation results that the water resources nature supporting-ability of Fuyang area is on the whole decreasing because in recent years,the paper making industry has developed too rapidly and the water consumption has been increasing sharply with increasing waste water discharge.Finally,some measures which improve nature supporting-ability of water resource in the area of Fuyang according to the present water resource state are put forward.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    YU Kong-jian, HAN Xi-li, ZHU Qiang
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    The speedy urbanization processes in China caused various ecological and environmental problems,and the degradation of water associated environment is one of the biggest issues.These problems were more than often resulted from"small decisions" and single minded engineering approaches in dealing with urban environment.It is highly recommended that a multifunctional and synthetic approach is required in order to solve the ecological and environmental problems in Chinese cities.Using the city Dongying as a case,this paper proposes a three-step approach to develop synthetic solutions to the ecological and environmental problems:(1)The synthesis of problems and definition of goals using Delphi method;(2)the development of strategic landscape structures which are integrated into the ecological infrastructure to solve the problems with multifunctional goals; and(3)the impact analysis regarding the proposed ecological infrastructure.A number of landscape strategies were proposed.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    LIU Hong-yu, LI Zhao-fu, LI Xiao-min
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    The northeastern Sanjiang Plain was once a largest fresh water wetland distribution area in China and an important habitat for Oriental White Storks (Ciconia boyciana)as well.But,with several large-scale land reclamation activities taking place in this region,large area of wetlands was converted into farmlands.As a result,wetlands were in very serious fragmented state,and very few Oriental White Storks were found in the heart of the study area since the 1980s.This phenomenon seems to be clearly related to wetlands changes in landscape scale. So, based on detailed field surveys on wetland landscape and habitat factors for Oriental White Storks,we established a GIS model to analyse the effect of wetland changes on habitats of Oriental White Storks in the study area.We got conclusions as follows:(1) The habitats of Oriental White Storks were composed of complex landscape of wetland types, in which island-like forest swamps were as nesting area and marshes,lakes and ponds as feeding area for Oriental White Storks in the study area.(2) Wetland landscape fragmentation has very serious impacts on habitats of Oriental White Storks. Patch area of wetlands had more effects on habitats when landscape matrix was in a lower fragmented state,that is,wetland area accounted of more than 50% of the total study area and landscape connectivity was higher than 50;and isolation in landscape,patch shape as well as landscape structure had more effects on habitats when wetland landscape was in higher fragmented state, that is,wetland landscape area accounted for less than 30% of the total study area and landscape connectivity was lower than 30.(3)Marsh wetland had more negative effects in area loss on habitats and lakes and ponds as well as island-like forest swamp had more negative effects in loss of patch number on habitats in the process of landscape fragmentation.(4)The restoration of habitats for Oriental White Storks needs to restore the key landscape types such as island-like forest swamp,ponds and marshes,to increase the connectivity between landscape of wetlands,to enlarge landscape matrix area and to restore landscape structure in landscape scale in the Sanjiang Plain for the feature.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    ZHAO Jin, CHEN Xi, BAO An-ming, DUAN Yuan-bin
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    Selection of optimum scales is one of the key issues in the studies of ecology,geography,etc.Scale laws for land use monitoring need to be found out in different periods.The natural ecosystems are seriously degenerated in the Tarim River Basin,which was paid great attention.In this study,the scale change laws of general land use and four main land use types including woodlands,shrubbery lands,sandy lands and saline or alkaline lands in the main stream area of the Tarim River are lucubrated by interpreting the land use data in the 1950s and in 2000 using the available maps and RS images.By regarding the areas of land use types as the scales,the parameters are selected,the histograms of the areas of patches are charted,the normalized scale variances at 9 scales (1:2000000,1:1000000,1:500000,1:250000,1:100000,1:50000,1:25000,1:10000 and 1:5000) are calculated,and the spatial distribution features and scale change laws of land use in the Tarim River Basin are lucubrated using normalized scale variances.Furthermore,sensitivity of land type with scale change is analyzed.The results are as follows:(1)The difference in areas of patches in the main stream area of the Tarim River is in great disparity,the patch of sandlands is the largest and its proportion in the year of 2000 was 43.77%.(2)The frequency distribution of the areas of patches,sandlands,saline or alkaline lands,woodlands and shrubbery lands in the main stream area of the Tarim River in the two study periods was in normal distribution,however,the positions of peak values and the distribution patterns were different,the positions of the peak values of sandlands and saline lands in the year of 2000 were in a range of 0.1~1km2 and those of others were in a range of 1~10km2.(3)The normalized scale variance figure reveals that most suitable scale of land use in general in the main stream area of the Tarim River is at 1:50000 or in a range of 1:50000~1:100000.Expect for the optimal scale of sandlands at a scale of 1:100000,the optimal scale of saline,woodlands and shrubbery lands is at a scale of 1:50000.The figures of normalized scale variances in the two study periods reveal that the change of the normalized scale variances of sandlands was tempestuous and was significantly higher than those of other land use types and; sensitivity of shrubbery lands was the highest,and then woodlands,saline and sandlands.Scale change rate was higher in 2000 than in the 1950s’.It was found that sensitivity of saline,woodlands and shrubbery lands showed a marked increase in 2000.On the contrary,sensitivity of sandlands decreased in 2000.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WANG Jing-sheng, LI Wen-hua, REN Qing-shan, LIU Mou-cheng
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    Forest is one of the most important terrestrial ecosystems on the earth.Besides supplying timber and other goods,forest has vital effect on environment and provides significant ecological services for people.Forest ecosystem as renewable resource is a type of public goods,which is non-competitive and non-exclusive.These two characteristics mean that the market is a poor provider of the socially optimal quantity of public goods.This is particularly important in China,which possesses limited forest resources and a large population.With rapid economic development,resources over-exploitation and environmental deterioration have become a bottleneck to the socio-economic development in China,and forest resources loss is believed to be closely associated with ecological and environmental degradations.Therefore,forest conservation has gained increasingly attention and the Chinese government has taken a series of actions to protect forest resources.This paper evaluates Tibet’s forest ecosystem services,and the main evaluation methods include market valuation,opportunity cost,shadow price,replace project,travel- cost and so on.As a result, the storage value of Tibet’s forest ecosystem services is 4454.35 billion yuan RMB,which includes C pool,timber products and biodiversity conservation,and the ecological vale is as 2.24 times as the direct economic value.Additionally,the flow value of Tibet’s forest ecosystem services is 173.83 billion yuan,including annual ecological vale which is 156.59 billion yuan,direct economic value 17.24 billion yuan and social value 0.95 billion yuan,and the ecological vale is as 9 times as the direct economic value.It is proved by the above-mentioned results that forest ecosystem can not only provide direct economic value for society,but also provide ecological function with much higher value,and all of these will provide a solid base for study and practice of eco-compensation and Green-GDP evaluation in Tibet.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WEI Xia, LI Zhan-bin, LI Xun-gui, SHEN Bing
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    By comprehensive investigating check dams,digging soil profiles of typical check dams, measuring the thickness of each alluvium and using reservoir storage-capacity curve,the depositing sediment of each alluvium for typical check dams was obtained.Based on the theory of sediment yields produced by storm and rainfall data in depositing process,the reversal of the corresponding erosive rainfall of each depositing sediment layer was obtained.The correlations between the depositing sediment and indexes of erosive rainfall including the maximum rainfall intensity in 30 minutes (I30),rainfall amount (P),rainfall erosivity (R) and average rainfall intensity (I) are studied in the paper.The result shows that the correlation degree between rainfall erosivity(R) and depositing sediment is the highest,and the second highest is rainfall amount(P).The relationships among depositing sediment and rainfall intensity in 30 minutes (I30),the average rainfall intensity (I) are lower.The relationships among depositing sediment and rainfall erosivity(R),rainfall amount(P) were established as dualistic linear regression equation in the paper.