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    Earth Surface Processes
  • Earth Surface Processes
    YANG Xiu-chun, XU Bin, ZHU Xiao-hua, TAO Wei-guo, LIU Tian-ke
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    There is an ecotone connecting farming region and pasturing region for northern agro-grazing ecotone. Its ecological function consists of conserving water sources, checking the wind and fixing the shifting sand, purifying air and maintaining biodiversity.Grassland is not only one of the important ecosystems, but also a background vegetation. Over the past decades, human activities have caused great land cover changes, such as desertification, grassland degradation, and sandy. Therefore, accurate and timely monitoring grassland is of critical importance for utilizing and administering grassland, developing pasturage and improving ecological environment. Using MODIS remote sensing data for the year 2005 and the ground measured grass yield of the corresponding period, linear regression model,non-linear regression models and BP neural network model were respectively established, to express the regression relationships between ground truth data and vegetation indices in this paper. Some conclusions are drawn as follows: (1) Regional models are better than whole-area general models. It is reasonable for the four grassland areas, and the regional models can better describe grass production.(2) Models based on BP neural network are better than linear regression models and non-linear regression models in fitness accuracy. Its decision coefficient increases by more than 3%, and the highest is 6.92%. Moreover, by precision validating, we find its root mean square error and relative errors are smaller, the models precision increases by more than 2.5%, and the maximum increases 23.22%. It is obvious that models based on BP neural network are most suitable for monitoring grass production of northern agro-grazing ecotone, and it can meet the need of estimating of grass production in northern agro-grazing ecotone.(3) The suitable vegetation indices for monitoring grass production of northern agro-grazing ecotone are NDVI and SAVI.(4) With the accumulation of the temporal scales data, further studies may focus on input data for BP neural network model. For example, input data may adopt soil moisture index and temperature and precipitation, and so on, which may further increase precision of models, and approach actual grass production for monitoring results.
  • Earth Surface Processes
    ZHANG Qing-nian
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    The theoretic and methodological research of map generalization is an important field in cartography and geographical information systems. The difficulties of map generalization lie in selectively omitting some features while maintaining the overall characteristics of their spatial distribution. Simplifying drainages is an important aspect of map generalization.Structural patterns and density differences are salient characteristics of drainages, which should be maintained in generalized versions. This paper proposed a new method to generalize dendritic drainages while maintaining the density differences between sub-drainages, which is based on the layered division of the number of retained rivers in river trees. We analyzed the layered structure of dendritic drainages and their density differences, and found the density differences inside a drainage come from the differences of the number of tributaries of its sub-drainages. A method to allocate the number of retained rivers is accordingly proposed, which divides the overall retained number of sub-drainages of a drainage according to the ratio of the number of the tributaries. The structured drainage generalization is executed in three steps. Firstly, the river entities and river trees are constructed, and the number of tributaries for each river is counted. Then the number of rivers to be retained in the generalized version is computed according to the Square Root Law. Lastly the number of retention is divided among all of the drainages according to the number of their tributaries, the mainstream of a drainage with big length and spacing is selected, and the allocation and selection are recursively executed in the lower layer until the number of the selected rivers reaches the limit of the drainage. The method was implemented as plug-ins in Java Environment. Experimental results are compared with the hand-made generalized maps. A case study of drainage generalization showed that the method created acceptable results and the density differences among drainages were maintained effectively.
  • Earth Surface Processes
    YANG Qing-sheng, LI Xia
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    This paper presents a new method to calibrate urban cellular automata (CA) using genetic algorithms(GA).The GA is used to find the optimal parameter values so that CA models can simulate urban expansion in a more realistic way. Traditional multi-criterion evaluation (MCE) and logistic methods have limitations for deriving the transition rules of CA models. The variables should be independent so that the parameter values (coefficients) can be properly estimated by regression analysis. This assumption is not true in most situations. The limitations can be overcome by using GA to estimate these parameter values for these correlated variables. When calibrating urban cellular automata with GA, the parameters of CA models are set to the chromosomes in GA program.The real number encoding way is used to encode chromosomes. The fitness function is defined with mean square error between simulated and actual urban forms.The initial population is set to be 50 randomly. And crossover probability is set to be 0.9, and mutation probability is set to be 0.01. The elitist selection is used to heredity the better individual.If the fitness does not change in the past 50 generations, the genetic procedure will be finished. After properly encoding the chromosomes, the optimal parameter values are automatically found by the evolutionary approach. This method is applied to the simulation of urban expansion in Dongguan, a fast developing city in the Pearl River Delta in South China. The model is able to simulate urban development in 1988-2004 by using the training data from remote sensing data. The analysis indicates that the proposed model can produce better simulation results than MCE-based CA models and logistic calibrated CA models. Moreover, the parameter values can be used to explain the relationships between spatial variables and urban development.
  • Earth Surface Processes
    WANG Bin, SITU Shang-ji
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    Place names are certain exclusive names of the physical or humanic geographic entities of specific space locations given by people and they are important signs through which the mankind knows the nature and human activities. As the language fossils, geographic names have the instructive functions to different historical periods and different regional social cultures. Located in the southern border area of China, Guangdong province which is affected by Central Plains and overseas culture deeply at the same time has its own peculiar development courses. This article adopts the GIS technology and establishes a Guangdong geographic name Yuan database (GEODATABASE) on the mathematical statistic basis. It also deals with the databases to output the straight side topic maps and other special maps which needs other special maps through ARCGIS GEOPROCESSING,SPACIAL STATISTICS TOOLBOX and ANALYSIS TOOLBOX according to the attribute essential factors as well as carries on dividing and color chromatic aberration processing. Finally, the place name landscapes of Guangdong demonstrate the peculiar geographical environment characteristics of the south of the Five Ridges and historical development characteristics: no harmoniousness in space distribution, varieties of common names and proper names, distributing concentration of neat head(qitou) place-names which have many ethnicities and dialects. The article also carries on geographical zoning on the basis of counting, and divides the geographic names Guangdong province into four big areas according to the types, namely the Hakkas(Kejia), the lucky man(Fulao), the Zhuang language(Zhuangyu) and the Cantonese(Yueyu) geographic name area, and they also respectively displays the core-edge proliferation pattern in space.
  • Earth Surface Processes
    LU Chang-he, JIA Ke-jing, RAN Sheng-hong, QI Yong-hua
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    According to the Law of Environment Assessment of China implemented in 2003, land use planning must conduct an assessment of its potential impacts on the environment, as to avoid the adverse environmental impacts of land use restructuring when the land use planning is implemented. For this purpose, this paper developed a procedure and proposed 11 indicators to estimate possible influences of the implementation of land use planning on the ecological security, environmental health, and land resources. These indicators cover five key aspects that may be affected by the implementation of land use planning, including ecological protection, land degradation control, arable land protection, built-up land expansion and its effects, and ecological risk of land reclamation. Further, as a case study, the procedure and indicators were applied to the China's Integrated Land Use Planning of 1997~2010, to examine the feasibility and reliability of the approach and indicators. The results of the case study show that implementation of the land use planning would greatly alleviate the environmental problems particularly of land degradation, enhance the ecosystems service functions, and improve the quality of arable land although the farmland area might decrease due to the built-up land encroachment. It concluded that the indicators can well reveal the potential effects of the implementation of land use planning on the environment, ecosystems and land resources, and thus the assessment is useful and valuable in supporting the land use planners or policymakers to sufficiently consider the environment issues in the formulation and implementation of land use planning.
  • Earth Surface Processes
    WANG Jun, QIU Yang, YANG Lei, DI Chao, YU Li
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    Land consolidation plays an important role in promoting rational land use and improving ecological environments. It produces the changes of land uses and their spatial structure to result in the changes of landscape pattern and ecological effects. Therefore, it is very important for planning and designing eco-environmental evaluation of land consolidation so as to study its landscape-ecological effects. Taking Huairou District in Beijing as an example, the changes of land use structure and landscape patterns for land consolidation are analyzed using GIS combined with method of landscape ecology in this paper. The following conclusions are drawn. The land consolidation converts most of other land uses into cultivated land, whose area is more than 70% of the project area. In this process, most of the unused land was transformed into the cultivated land, some forest land was changed into cultivated land. Whereas residential and industrial areas changed indistinctively. The number of land use patches and their density decreased by over 50%, the areas of average patch, the largest patch and the least patch increased 1.2, 0.4 and 79 times compared with those before land consolidation. However, the patch variance coefficient reduced by 24.18%. In the whole landscape, the land use patches became simple and regular, landscape edge density, shape index and splitting index decreased over 29%, whereas aggregation index slightly increased, when land consolidation has been finished. Land consolidation reduces landscape fragmentation. At the same time, it also causes decrease of landscape diversity. The Shannon's and Simpson's diversity index and evenness index reduce over 30%. Based on the characteristics of land consolidation and results of the previous researchers, the common 10 indexes of landscape effect analysis including patch level and landscape level are summarized.
  • Earth Surface Processes
    LIN Mu-xuan, SHI Ying-chun, CHEN Yang-fen, YU De-qing, He Qiong-feng, WANG Liang-jian
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    Construction land expansion is one of the notable features of urbanization.Analyzing the spatial-temporal features of construction land expansion can enhance the understanding of the nature of urbanization and provide with the grounds of decision-making for urban sustainable development. Based on the review of related research on construction land expansion at home and abroad, this paper takes Changsha urban area as an example, which is one of the most important cities in Central China.First, data on the variation of construction land in Changsha are obtained by employing the statistic and analytic function of GIS on the spatial data from remote sensing image data in different periods.Then the characteristics of construction land expansion are identified by using several methods in analyzing the spatial-temporal features of Changsha urban area from 1986 to 2004, which include expansion speed, expansion elasticity, fractal dimension, and rose map. The results obtained show that, during the last 20 years, the area of construction land has almost doubled, which is more obvious during the 2002-2004 period. Considering the relationship between the construction land area and population, the expansion speed of the construction land is far beyond that of the population, of which the erosion of arable land is most prominent. At present, the city sprawls by the way of low-density fill and the main direction of city expansion is NW270°-295° and SE165°-280°. Besides economic development and population growth, policy is also one of the important driving forces in construction land expansion. Especially in recent years, policy factor turns out to be the most determinant factor. In the future, the expansion mode of Changsha city will be that of mono-centric groups, and the direction of expansion will be more rational.
  • Earth Surface Processes
    SHAO Jing-an, WEI Chao-fu, XIE De-ti
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    Using a large data set gathered in household surveys conducted in Chongqing from December, 2003 to April, 2005, this paper examines some important aspects of agricultural land use under household responsibility system(HRS). The results indicate that the general trend is that the rate of land transfer is higher in the Yuxi economic corridor than in the metropolitan area, which, in turn, has a higher transfer rate than the Three-Gorges economic zone. Gradually, the mode of subcontracting has been accepted and adopted by the local farmers, and the modes of land renting and alienation in exchange of cash are beginning to appeal to some of the households. Land renting or leasing, is the chief form of land transfer in the metropolitan area, while most farm households in the Yuxi economic corridor and the Three-Gorges economic zone prefer the form of subcontracting, which does not terminate the original contract relations. The responses of land use patterns and land use environment to land transfer are noticeable in the sampling villages. Most of the transferred farmland in the metropolitan area is allotted to non-agricultural uses. In the Yuxi economic corridor and the Three-Gorges economic zone, only a small portion of the transferred land is used for non-agricultural uses and the intensiveness of land use is enhanced for most of it without major changes in land cover.The conditions of land tenure control the scope of land transfer without great inter-regional variation. The degree of development of the rural land market not only impacts the scope of land transfer in the region, but also constitutes the fundamental causes for the inter-regional variation in land transfer scope and in the evolution of transfer modes. Social security plays a decisive role in whether the farmers are willing to quit farming and in what way they will quit farming. Management of land transfer, which includes rights security management and land use management after the transfer, is essential for standardizing the behavior of the principal agents in land transfer, for reducing disputes in transfer and ensuring the smooth proceeding of land transfer according to law. Understanding the psychology of the farm households under the changing macroeconomic environment and their responses to the driving factors for land transfer is of tremendous significance to the establishment of a market law-abiding and human-oriented system for land transfer in China.
  • Earth Surface Processes
    HUANG Song, LI Jiang-feng, HU Ming-an
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    Xinjiang, the largest provincial region in China, is abundant in geological heritages. Influenced and restricted by the geological conditions and the geographical environment, the distribution of geology heritages in Xinjiang has an obvious spatial differentiation. Considering the deep fracture and the geostructure unit, which are the key factors influencing the spatial distribution of geological heritages, this thesis innovatively established the multi-level system of spatial pattern of geological heritages in Xinjiang. This system includes Altay, Zhunggar, Tianshan, Tarim and Kunlun-Altun, the 5 divisions of grade Ⅰ-- geological heritage belt; Southern Altay, Northern Altay, Western Junggar, Middle Junggar, Eastern Junggar, Northern Tianshan, Southern Tianshan, Western Tarim, Eastern Tarim, Western Kunlun, Middle Kunlun and Eastern Kunlun Altun the 13 units of grade Ⅱ-- the geological heritage area; and 35 units of grade Ⅲ-- the sub-geological heritage area. It designed 4 categories of quantitative indicators -- quantity, grade, type, protection condition, and 8 specific indicator factors -- quantity proportion and density of geological heritages, the proportion of nation and world-class geological heritages, geological heritage abundance, the average road distance from neighboring towns, the relationship with peripheral tourism resources, the proportion of protected geological heritages, the proportion of developed geological heritages. These indicators gave a comprehensive and quantitative characterizations on the spactial pattern of geological heritages in Xinjiang, and then, it was used to classify the units of Grade Ⅱ. These jobs laid the foundation of the research on the protection and exploitation of geological heritages in Xinjiang, which was based on geological heritage resources coupled with the human-land relationship. The results show that, in the cells of grade II, Northern Tianshan, Western Kunlun, Southern Tianshan, Northern Altay are identified to be excellent sites, while Turpan-Hami, Middle Zhunggar, eastern Tarim, Eastern Kunlun-Altun, Middle Kunlun, Western Tarim to be good; Southern Altay to be medium and Western Zhunggar, Eastern Zhunggar to be poor.
  • Earth Surface Processes
    KANG Xiang-wu, MA Xin, WU Shao-hong
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    The assessment on regional desertification degree is very important to prevent and control desertification. However, there are some problems about the assessment method of regional desertification degree. For example, the ecological meaning of spatial distribution of different types desertified land was ignored. And the influence of spatial distribution of different types of desertified land on overall regional desertification degree was neglected. In addition, while the area of every type of desertified land in the regions assessed is equal the assessment model fails to work. Therefore, the factor of ecological meaning of land spatial distribution on different types of sand and the factor affected the regional desertification degree should be added to the regional desertification assessment methods. To solve these problems, we selected the landscape pattern index and aggregation index according to landscape ecology principle, and applied them to construct regional desertification degree assessment model through RS and GIS technology. Finally the regional desertification degree in the six counties of Hunshandake Sandy Land was assessed by applying the model. The result suggested that this method can distinguish the desertification degree in different periods. Therefore, according to the assessment result,Zhenglanqi should enhance the control of desertification,and Guyuan county and Taibus should prevent regional desertification.
  • Earth Surface Processes
    ZHU Yuan, KANG Mu-yi, Liu Quan-ru, Su Yun, Jiang Yuan
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    Coniferous forest in Helan Mountain is the relatively rare forest ecosystem in northwestern China. For the conservation of forest, the structure and floristic composition of coniferous forest have been studied. Based on principal components analysis of forest structure, mainly four kinds of forest could be obtained, that is diameter at breast height (DBH) of trees mostly less than 10 cm, DBH of trees mostly between 10 and 20 cm, DBH of trees distributed approximally equally and DBH of trees mostly greater than 30 cm. The result mainly reflected the times after prohibition of logging, and also indictated the effects imposed by altitude. Based on TWINSPAN analysis of species composition, six plant associations could be found, which were mainly influenced by altitude. The species density in spruce-moss forest was the minimum in the whole coniferous forest. Ascending from spruce-moss forest, the forest disappeared gradually and overlapped with alpine bushes and meadow, with species density increasing. Decreasing with altitude, the floristic composition changed and species density increased. Down to the lowest pine forest, the species was most abundant. The comparison of the classification of forest structure with that of species composition indicated that, though the criteria of analyses were different and the features of forest were viewed from different sides, there existed some inherent relations between foreset structure and floristic composition. The forest structure and species composition were all mainly influenced by altitude. When the forest structures were similar, several plant associations could be found, but one assicoation always belonged to single forest structural type.
  • Earth Surface Processes
    ZHANG Ke-li, PENG Wen-ying, WANG Long, FU An-ping, XU Xiang-lan
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    Soil erosion in black soil region in Northeast China leads to soil redistribution on a slope and great spatial variance in the thickness of soil humus layer. Changes of humus layer thickness will result in such physical properties variations as soil moisture and soil temperature. And soil moisture and soil temperature are important factors for freeze-thaw erosion, besides they can affect soil particles and chemical elements movement on the surface and soil profile. In order to explore the law of changes of soil moisture and soil temperature by time and depth of soil profile, two field monitoring points A and B were selected to monitor soil moisture and soil temperature simultaneously. At site A, soil humus layer is about 60 cm, and at site B, soil humus layer is about 130 cm. Soil temperature was recorded with a thermistor thermometer at eight o'clock a. m. everyday from 10 April to 14 June and twice a week from 23 January to 7 April. Soil moisture was monitored with an oven after sampling by drills. Soil moisture and temperature were measured at an interval of 10 cm from the surface to 150 cm deep on two profiles in the paper. Results show that the thickness of humus layer has significant influences on soil moisture and soil temperature. The thicker the humus layer is, the slower the rate of thaw. At site A, the rate of thaw was 2.4cm/day, however, it was 2.1cm/day at site B. Furthermore, the freeze time lags a week or so. At the same time, soil moisture of thicker humus layers is more than that of thinner humus layers in black soil region, as well as the moving extent of soil moisture is deeper. The humus layer has a great impact on the distribution of soil moisture on the profile. As a result, runoff rate during a rainstorm will occur differently from place to place because of the diversity in humus layer depth on a slope.
  • Earth Surface Processes
    ZHANG Bo, ZHANG Hua, ZHANG Kai, ZHANG Ming-jun, LIN Qing, LU An-xin, GUO Zheng-gang
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    Taking Pingchuan and Liuba oases in the middle reaches of the Heihe River as examples, the spatial diversification of soil moisture content in oasis and ecotone is analysed using methods of combination of field sampling with laboratory analysis. The results show that the level diversification of soil moisture content along the oasis-desert is distinct in nonirrigated areas, the soil moisture content is higher than that of ecotone and desert. The soil moisture content shows a declining trend from the oasis to ecotone and desert, that is, the soil moisture content decreases from 20% in oasis to 2.9% in the oasis-desert ecotone. Firstly, the differences of soil moisture content are mostly influenced by soil characteristics and soil texture, secondly, influenced by microclimate conditions such as level airflow near ground of oasis-desert belts where soil can transport vapor from oasis area to near desert, and thirdly, the oasis soil moisture content likely moves levelly to desert soil. The active layer soil moisture content at soil profile in the oasis shows an increasing trend from surface layer to understratum. In the range of 0~60cm, the trend of soil moisture content increases in evidence from surface layer to understratum, and the change extent is about 3.12%~21.77%. Whereas in the ecotone and desert soil profiles, the soil moisture contents in surface layer and understratum are lower than that in the middle layer of 20~30cm, this is likely related with the formation and movement of condensation water of desert soil. It is proved that there is dry sand bed in 0~20cm that has distinct restrained effect to evaporation in substrate.It is beneficial to soil moisture content maintenance in that layer. It has important ecological meaning for sandy vegetation. Because of over extracting of groundwater in the oasis and obvious impact of human activities in the ecotone, the ecological gap has been formed, constituting a threat to the ecosystem security. The changes of soil moisture content in the oasis-desert ecological ecotone reflect the extents of water utilization of human being.
  • Earth Surface Processes
    YANG Pei-guo, YANG Qin-ye, WU Shao-hong, MA Xin, KANG Xiang-wu, XIA Fu-qiang, DAI Er-fu
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    Flood disaster is still a threat in the lower Yellow River due to unusual precipitation caused by the deposit of channel, the hidden danger in the embankment and unfavorable riverbed in the lower Yellow River. Study on the embankment-break flood characteristics of the lower Yellow River can afford the scientific basis for flood disaster mitigation. According to the characteristics of the embankment-break flood in the Yellow River,flood routing characteristics of embankment-break is simulated at four different locations of the lower Yellow River by inputting terrain data, typical historical flood data and land use data of the study area to two-dimensional unsteady-state flow model. Simulated results show that: Firstly, routing flood encroach the rivers on the way and enter into the rivers after reaching the lower reaches;secondly, in the same river reach, flood submerged area of north band is bigger than the corresponding location of south bank towards the same historical flood;thirdly, it is different in flood submerged degree of different regions due to the different spatial locations of floodplain; and fourthly, the area of mainstream where flood depth is high and flood velocity is quick is relatively small, but the area of non-mainstream where flood depth is low and flood velocity is slow is relatively big. Flood disaster risk in the protected zone of the embankment will be analyzed by using the results of the simulated flood in this paper, on the basis of the simulated results, the spatial pattern of the flood disaster risk in the protected zone will be analyzed in the lower Yellow River in the future. The attempt on the simulated methods and technique of the flood routing can serve as a reference to the researches in other similar regions. In this study, some factors such as the sediment, infiltration and evaporation weren't considered, which is a limitation to research the hydraulic characteristic of the levee-breaking flood in the Yellow River. In the succeeding simulation, the sediment should be considered to research the long-term influence on the local environment of preventing flood due to the deposit of the sediment in the riverway. At the same time the surface features should the whole way be close to the reality.
  • Earth Surface Processes
    RAN Sheng-hong, LI Xiu-bin, LU Chang-he
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    Based on remote sensing images in three different years (1986, 1994 and 2002), patch-dynamics model is used to simulate the annual land use/cover change (LUCC) from 1986 to 2004 in Yuzixi catchment. Using the modeling results of LUCC, the linear regression model and multivariate nonlinear regression model are employed to analyze the relationship between runoff, rainfall and LUCC at different time scales. The results show that: (1) The correlation coefficients between rainfall and runoff at different time scales are significantly different. The coefficient at monthly scale is the largest, which is 0.807. The coefficient at daily scale is the smallest (0.311). The results also show that, at daily scale, the time lag of rainfall and runoff has to be taken into account. (2) The results of partial correlation analysis show that, at different time scales, LUCC has significant impacts on the relationship between rainfall and runoff. At yearly scale, the impact of rainfall on runoff is larger than that of temperature on runoff, while the results at monthly scale are the reverse. The relationships between runoff and LUCC in Yuzixi catchment at different time scales are also different. Only at monthly scale, the significance of partial correlation analysis is acceptable. (3) At different time scales, the modeling accuracies of multivariate nonlinear regression analysis are higher than that of linear regression analysis. The nonlinear characteristics of different factors at different time scales are different. For example, the nonlinear index of rainfall at monthly scale is the largest (8.3) and the nonlinear index at daily scale is the smallest (0.4) (runoff is the dependent variable). The nonlinear index of temperature is 2.2 at month scale and the nonlinear index is 1.6 at daily scale. The nonlinear index of resident area is 0.725 at monthly scale and the nonlinear index is 1.01 at daily scale.
  • Earth Surface Processes
    XU Hai-liang, WANG Xiao-ping, YE Mao, Aihemti, Wumairjiang
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    The ecological protection and environmental treatment are the main goal of implementing the eco-water transfer project (EWTP) in the lower reaches of the Tarim River. Whether it can improve environment and promote local economic development or not has become a concerned problem. This paper adopts the questionnaire investigation to reflect the social benefits of the eco-water transfer to the lower reaches of the Tarim River. The results show: (1)above 90% of the investigators accept that the EWTP is closely related to themselves, and has a favorable impact on their income, local economy and eco-environment. Thus, 82% of the households hope implementing continually the EWTP. (2) The annual incomes of more than 76% of the households have an increasing trend to some degrees after eco-water transfer.The result indicates that the favorable changes of eco-environment after water transfer have a positive function on the local economic development. (3) In terms of households willingness to pay, above 70% of the households will pay for their labors to support continual water transfer while 15% will pay for money, and 6% will pay for both of them. The result shows that the households' willingness to continual water transfer is obvious, which is relative to the local economic development and people's living standard. (4) Seen from the environmental changes perceived by the households and shepherds, the changing degree of the eco-environmental factors is in the order of the decrease of the times of blowing wind-sand> the favorable growth of the natural vegetation> the increase of the wild animals> the increase of the plants species. The result is also consistent with the monitoring result in field. On all accounts, the EWTP plays forward a positive role in both households and shepherds' living and eco-environment. The social benefits caused by the EWTP are obvious in the lower reaches of the Tarim River.
  • Earth Surface Processes
    MENG Xiao-chen, ZHAO Xing-shuo, MAIMAI Ti-jiang
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    Since the formal use by Prof. Pierre Bourdieu, the concept of social capital has been discussed and expanded in international academic field.In this paper, the authors definite social capital as social network and take it as the channel of resources distribution. The study paid attention to the impact of capital flow through the social network on local economy and its change with time. The social network chosen in the study is overseas relationship and the case studied is Xinhui, the famous overseas Chinese hometown in Guangdong province, with 713,000 overseas fellows that is 82% of the total population. Based on the analysis of statistical data, questionnaires and interviews, the authors found there are three ways of capital flow into local economy through social network, emigrant remittance,donation and direct investment. Emigrant remittance is the source of civil capital accumulation. Donation improved the local infrastructure. Direct investment contributes to the local economic growth directly. The importance of the three ways is different with time, but all played the key roles in the taking off of local economy. The authors also found that the impact of social network has a trend of weakening down. The amount of emigrant remittance and donation increased in the 1980s and then decreased in the 1990s. At the same time, direct investment has over past the former two ways.Considering the background of China's economic reform from planned economy to market economy since the early 1980s, social network played a compensation role between weakened planning and immature market. With the improvement of market institution, social network is withdrawing from the resources distribution. For local sustainable development, market building and environment improvement are more important in the future.
  • Earth Surface Processes
    YANG Zhen-shan, CAI Jian-ming
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    As a brand-new type of agricultural development, urban agriculture has gained its deserved attention in the world since the 1980s. With the irresistible trend of urbanization and serious urban-rural relationship, it theoretically is expected as a new concept and a route to create multi-function: economic, ecological, and social. In practice, however, the more important, but less discussed question is on how to make urban agriculture powerful and how to make it adaptable to the urban economic system. Empirical experiences tell that enterprise is the most effective form to organize and develop urban agricultural industry under the market economic system. It can organize the productive elements and balance the power and the interest among the stakeholders, such as the government, the farmer and other enterprises, all of which are playing crucial roles in the urban agricultural development. Based on the investigation of Mutual Benefit International Food Group Co. ,Ltd.(MBIF), this paper explores the mechanism and dynamics of the food processing oriented.urban agriculture enterprises.By aid of first-hand information and data, the discussion on the enterprise operation is expanded at three levels, from outside to the core. The outer mechanism discusses how the enterprise obtains the government and community support; the inner mechanism focuses on its production and management; the core mechanism is on the enterprise competitiveness formation by innovation and cultivating control power. Besides, the relationships among the above mechanisms are disclosed. According to the findings, the paper abstracts the development mechanism of food processing oriented urban agriculture enterprises as a"fish model". The paper further provides suggestive instructions on developing urban agriculture enterprises and makes amendatory measures on the existing problems. The authors finally come up with several key issues for the new but very promising industry, to strengthen the future urban agriculture development.

  • Earth Surface Processes
    ZHANG Yu-feng, LI Jing
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    On the basis of introducing the connotation of the reference land price(RLP)and by adopting the comparative and analysis method,this paper analyzes the characteristics of RLP of the town in five counties of Hohhot from the aspects of nature, society and economy. The regional distribution of RLP and the relation between RLP of the towns and its influencing factors is expatiated. The conclusion is that no matter what level and what type of land, the direction is that the town RLP of Tumd Left Banner, Togtoh County and Horinger County is higher than that in Wuchuan County and Qingshuihe County. If the land level is high, the RLP is high, which shows their positive correlative connection of each town and reflects the difference in land locational condition and land use benefit. The RLP of land for business, housing and industrial purposes presents a decreasing trend, with an average ratio of 4.22∶1.50∶1. The distribution of RLP of business forms a higher price area because of facing primary road. The RLP for housing purpose becomes lower with distance accretion from town center. The RLP for industrial purpose is lower than that of land for business and housing, because benefit from industrial land use is much lower than the latter two and its locational request is relatively low. Town layout factor has important function in the evaluation of RLP of the towns. The RLP of the towns is closely related with the localional factors.Of the influencing factors of the town RLP, the natural condition mostly includes landform, climate, hydrology, the social condition mostly includes population status, perfect degree of public infrastructure and the economic condition mostly includes per capita GDP data, financial earning, per capita disposable income, traffic condition, etc. They collectively affect the RLP from different aspects. They show an identical changing trend with land price. The influencing factors should be improved to reduce difference of the RLP and promote development of regional economy. The research will play a stimulative role to develop land market of Hohhot in the future, guide reasonable, intensive and efficient exploitation of the land, and bring into play the land potential value, and afford gist and method for the grading of the urban land in Inner Mongolia. It will accelerate management of land market.
  • Earth Surface Processes
    DU Guo-ming, ZHANG Shu-wen, ZHANG You-quan
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    For detecting the applicability of classical urban population density models on the microcosmiclevel, this paper calculates grid-based population landscape density of Shenyang city, analyzes it's spiatial auto-correlation and variability using theories and methods of geostatiatics. It is found out that all semivariogram functions of populatin density fit with spherical model with negget in ten kinds of grains from 100m to 1000m, indicating that population distribution presents structural characteristics in the spatial extension of Shenyang city. But because of different grains, the auto-correlation scales, neggets, and stills, the rate of negget and still is different. This means that spatial auto-correlation of population distribution depended on the scale intensively, resulting in scale effects.By calculating semivariogram functions curves of different directions, it can be found that population density takes on a classical zonal anisotropy, which means that there were different structural characteristics in different directions for poplation distribution. The analysis of population density auto-crrelation and variability should be taken as bases for researching urban population density distribution. The impacts of grain on population density auto-correlation and anisotropy are objective, so more attention should be paid to choosing feasible scale and identifying structure of population distribution. In the specific time for a certain city, the condition of population distribution is objective, while population density models are abstract expressions of population distribution characteristics, whose parameters are only quantitative indexes of expressing population distribution pattern. So, when researching spatial structure of population distribution in a city, the emphases should be put on how to identify spatial structural characteristics of population distribution, rather than on how to apply classical population density models mechanically.
  • Earth Surface Processes
    WU Wei, CAO You-hui, CAO Wei-dong, LIANG Shuang-bo
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    Choosing weighted average travel times as indicator, county as research unit, this paper analyses the accessibility patterns of highway, railway, waterway and civil aviation respectively in the Yangtze River Delta under opening conditions, with these results, the accessibility patterns of integrated transportation are elaborated. The accessibility of highway takes on a layered pattern with Shanghai, Suzhou and Jiaxing as the center, which implicates the transport convenience of nodes within the region. Most nodes are better but those located in the south of Taizhou and Zhoushan (Zhejiang province) are worse in railway accessibility. In waterway transport, the accessibility shows an arc belt pattern, with better accessibility, in the center composed of Shanghai, Ningbo and Zhoushan, the belt along the Yangtze River in the north and along the East China Sea in the south but it decreases southwestwards and northwards (northeastwards).The accessibility of civil aviation takes on a south-north symmetry pattern approximately, having nodes with better accessibility concentrated in the middle part. Shanghai is the best node in civil aviation accessibility, Hangzhou, Nanjing and Ningbo are better than those nodes around them, which form the "islands-shaped" pattern. As to integrated transportation, Shanghai and nodes around it are best in accessibility, centered around this area, the accessibility decreases to the periphery, and the area with better accessibility forms "Z-shaped" pattern, which is consistent with the regional transport and megalopolis pattern, and the accessibility of the nodes in the south and north edge are worse, as a whole, the north is better than the south and the east is better than the west in accessibility. According to the analysis of accessibility coefficient, the highway is the best one in equilibrium of accessibility distribution, integrated and civil aviation transportation takes the second place, waterway is worse, and railway is the worst. For the sake of integration of this region, the consummation of integrated transportation system should be focused on improving the accessibility of the edge nodes in the future.
  • Earth Surface Processes
    LIN Lan, KANG Zhi-lin, GAN Meng-yu, YE Jin-yu
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    To put up with the lack of flow and current direction data among tourism destinations, which are important for research, this paper illustrates the different spatial field effects of tourist flow of Taiwanese visiting Mainland China due to the choice of different ports, by taking the database technique based on the principle of network analysis. It was found that the tourist flow relation among tourists taking Guangzhou-Guangzhou and Shanghai-Shanghai respectively as their entry and exit ports is comparatively better developed; then comes Beijing-Beijing, Shanghai-Guangzhou. However, the spatial field development of tourist flow among tourists taking Beijing-Shanghai(or Shanghai-Beijing) and Beijing-Guangzhou(or Guangzhou-Beijing) respectively as their entry and exit ports is much weaker. Such a pattern of spatial field effect should be attributed to the combined impacts of factors like regional supply of tourist resources, the tourist market demand (such as preference for products and limited time for traveling), transport media for traveling (intensity and tightness of airline network linkage) and marketing of travel agencies. The result of such a research could provide reference for the cooperation and development of regional tourism of Taiwanese visiting Mainland China. This paper only analyzes some factors such as the subjective initiative of tourist flow(the disposable time for traveling), the intermediary condition (transportation intermediary, marketing of travel agencies) and so on, which make the spatial effect of tourist flow of Taiwanese visiting Mainland China based on airports change. But the paper neglects the influence of some attribute factors of tourism destination, for example economic, political and social structures, geopolitical relations and so on, which decides the intensity and range of the tourist flow's spatial effect to a certain extent. How to bring these factors into the quantitative research on the tourist flow's spatial effects is still awaiting to be further explored and make breakthroughs.
  • Earth Surface Processes
    XU Lin, DONG Suo-cheng, AI Hua, QI Xiao-ming, WANG Pei-xian
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    In order to satisfy the traveling demand which grows unceasingly and tends to be diversified and multilevel, the traveling industry chain is extending unceasingly and forming comprehensive tourism which has high interrelations with other industries and has multiple combined earnings. Comprehensive tourism is a kind of mature pattern of the tourism industrial development, which is broader and more comprehensive than the traditional tourism industriy in aspects of connotation. In this paper, the connotation, the characteristic and the industrial system of comprehensive tourism are discussed explicitly, especially from the viewpoint of the exploitation of advantageous resources, the resources substitution and the industrial substitution. Furthermore, the impacts, effects and benefits of comprehensive tourism industry are analyzed from both theoretical and empirical study, based on the case of Gansu Province.The authors emphasized in this paper that tourism can accelerate less-developed areas to win the multiple benefits in regional economy, society and ecology, as well as resources comprehensive utilization. Compared with traditional industry, comprehensive tourism has obvious advantages and prospects in regional development. In terms of theory, the comprehensive tourism industry imposes its impacts on the economy, the society and the ecology which are universal and multilevel, reflecting in three aspects: impacts on national economy, impacts on social development and impacts on environment. In terms of empirical study, on the basis of theoretical study, the data analysis of Gansu Province has been carried out, which showed that comprehensive tourism, as a new high growing industry, had strong economical, social and ecological impacts in the province. The paper concluded that being an environment-friendly industry with multi-benefits and impacts, comprehensive tourism has the functions of driving regional economic development, increasing employment, mitigating ecological pressure, especially in the less-developed areas. Some policy suggestions have been made to the development of comprehensive tourism in a more scientific and effective way.