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    Resources Utilization and Management
  • Resources Utilization and Management
    TAN Ming-hong, LI Xiu-bin
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    The urban land per capita always inspires researchers working in the fields of urban planning, geography and urban/regional planning, because it is a basic parameter for urban planning and land use planning. In 1991, the standard of urban land per capita came into operation, which has become one of the important indexes for judging whether urban planning is reasonable at the different levels in China. However, after the rapid urbanization and economic development of 20 years, can the standard still meet the increasing demand of urban land in this country? In response to the question, this study discusses the differences of urban land per capita for 80 countries with the largest population in the world, using the data from the Demograhia website, FAO and World Bank, etc. Furthermore, the factors causing the differences are examined, using the cross-sectional data of these countries. The results show that urban land per capita has a positive relationship with land resources per capita and GDP per capita. And the latter has more influence on the differences than the former. In addition, the percentage of arable land and permanent crop land to the total land also has a relationship with urban land per capita. In China, urban land per capita will increase with economic development and might approach 165 m2 in 2020, which is higher than that of the present level (155 m2) and much higher than the upper limit of the standard of urban land per capita (120 m2).
  • Resources Utilization and Management
    LI Xue-mei, ZHANG Xiao-lei, DU Hong-ru, CAO Jian-biao
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    Mineral resource exploitation has important impact on regional economic development, industrialization level and urbanization. Taking Xinjiang as an example, this paper analyses the basic feature of mineral resource exploitation, economic development, industrialization level and urbanization. On this basis, dynamic computation model is established to discuss the relativity of mineral resource exploitation, economic development, industrialization level and urbanization by the method of Granger causality test and co-integration analysis. The conclusions are as follows: Over the years, the development of mineral resources has affected economic development, industrialization and urbanization level. Whenever the mineral resource exploitation index increases by 1%, it will lead to a 0.24% increase of industrialization level and 1.25% increase of urbanization level. Mineral resource exploitation is the causation of development of industrialization level and urbanization level, urbanization level and development of industrialization level is the causation of mineral resource exploitation; economic development and urbanization level is the causation of mineral resource exploitation, but mineral resource exploitation is not the causation of economic development. At present, resource superiority is the favorable condition to the development of Xinjiang’s economiy, which is not plunge into the trap of "resource curse". The four systems of mineral resource exploitation, economic development, the level of industrialization and the level of urbanization interact, and jointly promote the mutual development in Xinjiang. How to perfect land provision system to meet the demand of economic growth,industrialization and urbanization at present are very pressing strategic issues.
  • Resources Utilization and Management
    MA Qun, ZHAO Geng-xing
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    Based on field investigation, laboratory analysis and SPSS software, this paper took Shouguang city of Shandong Province as a case, systematically analyzed the distribution, variation and relevance of soil nutrients to research soil nutrient change under different land use types. The results showed that there was an obvious order in the distribution of soil nutrient content under different land use types: the distribution of organic matter was vegetable land>irrigable land>garden>farmland>saline-alkaline land; the distribution of total-N, available-N, K, P and Zn was vegetable land>garden>irrigable land>saline-alkaline land>farmland; the distribution of pH value and exchangeable-Mg was saline-alkaline land>farmland>irrigable land>garden>vegetable land; the distribution of exchangeable-Ca under different land use types was saline-alkaline land>farmland>irrigable land>vegetable land>garden; the distribution of available-B was garden>vegetable land>saline-alkaline land>irrigable land>farmland; the distribution of available-Fe was vegetable land>garden>irrigable land>farmland>saline-alkaline land; and the distribution of available-Cu and available-Mn was garden>vegetable land>irrigable land>saline-alkaline land>farmland. The variance of nutrient content between irrigable land, vegetable land and garden was comparatively low, and the variance of nutrient content between farmland and saline-alkaline land was similar. Except for pH, the variance coefficients of the other 12 kinds of soil nutrients under different land use types were all comparatively high, of which the highest variance coefficient was for available-P. Except for exchangeable-Mg and B with other nutrients, the relevance among the others was almost significant or marked significant. The relevance between pH value and the other soil nutrients was significant or highly significant negative correlation, while the relevance of organic matter with other nutrients showed significant or highly significant positive correlation.
  • Resources Utilization and Management
    JIN Guang-ze, YANG Gui-yan, MA Jian-zhang, LI Lan-jun, XU Zheng-gang, ZHAO Xue, HONG Mei-jing
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    To study the effect of anthropogenic cone picking on the seed bank and seedling bank of Korean pine (Pinus koraiensis) in the major forest types in Lesser Hing’an Mountains, mixed broad-leaved Korean pine forest, Korean pine plantation near the mixed broad-leaved Korean pine forest, Dahurian larch (Larix gmelini) plantation, white birch (Betula platyphylla) forest and spruce-fir forest were selected. In each of these forest types, sample belts with the size of 10 m×240 m were made to study the seed bank and seedling bank of Korean pine. The results showed: 1) The amount of Korean pine seed bank differed greatly with forest types. The largest amount of seed bank was shown in the mixed broad-leaved Korean pine forest, followed by the Dahurian larch plantation, spruce-fir forest, Korean pine plantation and white birch forest. 2) Seeds that were cracked or destroyed by rodents and other animals accounted for 81.9%-90.4% of the seed bank of those major forest types; intact seeds were only found in the mixed broad-leaved Korean pine forest and Dahurian larch plantation, with 4.3% and 4.9%, respectively. 3) Korean pine seeds were mostly distributed in the 0-10 cm soil layer (71.4%-91.3% of the seed bank of those major forest types). 4) The density of Korean pine seedling bank was the highest in Dahurian larch forest (1613 seedlings·hm-2), lowest in Korean pine plantation (167 seedlings·hm-2), Korean pine seedling density in the mixed broad-leaved Korean pine forest (293 seedlings·hm-2) and white birch forest (854 seedlings·hm-2) were 1/68-1/9 and 1/9-1/4.5 of the seedling bank before cone picking, respectively. 5) For the age class distribution, before cone picking, in the mixed broad-leaved Korean pine forest, the amount of Korean pine seedlings decreased as the age class increased, the age class distribution showed a reverse J-shaped distribution; in the white birch forest, density of the Korean pine seedlings was relatively the same in each of the age class. After cone picking, in the mixed broad-leaved Korean pine forest, density of the Korean pine seedlings was relatively the same in each of the age class; in the white birch forest, the age class distribution of Korean pine seedlings showed a reverse J-shaped distribution.
  • Resources Safety
  • Resources Safety
    ZHANG Shi-feng, CHEN Jun-xu, HUA Dong, MENG Xiu-jing
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    There are lots of factors influencing the water resources system, making it difficult to calculate water resources system risk accurately with a single index. In this paper, on the basis of discussing the risk transfer process and the risk factors from environment, economy and society, the index system for assessment of water resource system risk which consisted of 20 practical indexes in total from four characteristics was established. A model was established on the basis of the index system to assess the water resource system risk, system counterforce ability and risk damage. Parameter calculation of risk and the risk classification is easy to implement with the model. The water resource system risk in Beijing was evaluated with the index system and the model in this paper. The results show that the water risk index is 26.97%, lower than the risk-causing rate which is 57.13%, the difference that does demonstrate the importance of the water system counterforce ability is caused by the water resource system counterforce ability. The main risk-causing factor and system counterforce ability factor are the rate of water shortage and the water guarantee rate, being 0.4261 and 0.6476 respectively. The risk results show that Beijing falls in the second category, to guard against the risk, restrictions on the use of water resources and management of water environment should be taken into effect.
  • Resources Ecology
  • Resources Ecology
    MENG Jie, BU Chong-feng, ZHAO Yu-jiao, ZHANG Xing-chang
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    Biological soil crust (BSC) exerts important ecological functions in the arid and semi-arid ecosystems. In this paper, the effects of BSC on soil enzyme (urease, catalase and alkaline phosphatase) activities and nutrients (soil organic matter, total N, available N, P and K) content were studied in the revegetated lands in the water-wind erosion crisscross region on the Loess Plateau, northern Shaanxi Province of China. The results indicated that compared to no crust, BSC could significantly improve soil enzyme activities in crust,but had no significant increase effect on soil enzyme activities in subsoil. The activities of soil urease and catalase in crust layer were 1.56 and 1.31 times as high as that in 0-2 cm topsoil under crust, respectively. The increasing extent of soil alkaline phosphatase activity in crust was the biggest, which was 3.72 times of that in 0-2 cm topsoil under crust. Soil nutrients accumulation effects of BSC were obvious mainly in crust soil. In this study, BSC significantly increased the content of soil organic matter, total N and available N in crust (P<0.05),but the increase effects of available P and K were not significant (P>0.05). The contents of soil organic matter, total N and available N were 15.67 g·kg-1, 0.65 g·kg-1 and 22.51 mg·kg-1 in crust, and were 5.54 g·kg-1, 0.30 g·kg-1 and 14.6 mg·kg-1 in 0-2 cm topsoil under crust, respectively. The soil pH was 8.08 in crust, which was lower than that in 0-2 cm topsoil under crust (pH=8.32, P<0.05). The decrease effect of BSC on soil pH was helpful to improve the soil nutrients bioavailability. Therefore, it can be concluded that the formation and development of BSC would be beneficial to bettering surface soil biochemical properties, which can promote vegetation restoration and reconstruction in such arid and semiarid regions. There were many factors which influenced the formation and development of BSC. Therefore, effects of BSC on soil enzyme activities and nutrients under different environmental conditions and various vegetation types should be paid more attention in the further studies.
  • Resources Ecology
    YOU He-yuan, WU Ci-fang
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    Carbon emission efficiency is payid more attention to the effect of carbon emission which is considered as cost on desired output, but some indicators, such as total carbon emission and carbon emission per unit land area, neglect this effect. In this paper, the key consideration of carbon emission is the carbon emission brought by energy which is consumed in land use. Based on the input-oriented model of CCR and BCC, the carbon emission efficiency of land use that is composed of the total efficiency, technical efficiency, scale efficiency and returns to scale is calculated. The computed results indicate that: 1) the total efficiencies of carbon emission in Inner Mongolia, Fujian, Guangxi and Qinghai were 1.0000, and they were DEA efficient among the 30 provinces(not including Tibet, Hong Kong, Macao and Taiwan due to no data). The total efficiency of carbon emission in Shanghai was 0.0469, and it was the least among the 30 provinces. The total efficiency of carbon emission in the other provinces was from 0.0682 to 0.8965. 2) There was a relationship between the features of land use and the distribution of technical efficiency and scale efficiency, the efficiency value of carbon emission was also affected by the features of land use. The distribution of regions whose scale efficiencies were efficient, was smaller than the distribution of regions whose technical efficiencies were efficient. 3) The provinces whose scale efficiencies were efficient, different from the provinces with constant returns to scale. Therefore, the returns to scale of the provinces should be taken into account if the scale efficiency of carbon emission efficiency of land use is wanted to improve. In order to insure DEA efficiency of carbon emission of land use in all provinces, the inputs optimization and outputs optimization of land use in 26 provinces which are not DEA efficient are designed. The optimization based on the perspective of low carbon also calculates the input redundancy and output shortage. Finally, according to the results of low carbon optimization, measures are taken to make land use low carbon emission. The measures are composed of the energy input control in land use and land output optimization based on optimal allocation of land resource. Carbon emission efficiency of land use can achieve DEA efficiency if these measures are implemented.
  • Resources Ecology
    WANG Ji-jun, LI Hui, SU Xin, DU Na
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    Coupling relationship of agricultural eco-economic system is a complex process, and it is an interactive result of latent variable and latent variable, latent variable and measurable variable and measurable variable and measurable variable. The complex relationship can be described sufficiently by construction of structural equation model. The results of the structure equation model of three typical areas of Wuqi County, mesoscale eco-agricultural demonstration experiment built by Ansai County and Baota District, and Mizhi county represent loess hilly-gully region, and the establishment and operation of each region indicate that the operation mode of agricultural eco-economic system reveals essential pattern of mutual coupling of agricultural industry and agricultural resources basically with the outside force of Grain for Green Project,but the status of coupled model does not make full use of agricultural resources, and the system coupling effect is low, the impact coefficients of agricultural industry and agricultural resources to the system coupling are 0.54 and 0.16, correlation coefficient between the agricultural industry and agricultural resources is only 0.28, that is to say, industrial development is not well supported by agricultural resources, which resulted in a nonobvious agricultural eco-economic system coupling effect, the existence of local "contrary to" posture, the potential loss phenomenon of forest and pasture resources associated with the industrial chain net. Therefore, the continuous improvement of the system coupling effect and increase economic benefits, the interactive process of agricultural industry and agricultural resources should be strengthened, in particular, the grass and trees and related industries should be developed. The effective use of forest and pasture resources should be promoted.
  • Resources Evaluation
  • Resources Evaluation
    HAO Li-sha, ZHAO Yuan
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    Taking proved oil reserves as indicator, this paper analyzes the spatial distribution pattern of global oil resources and its evolution in 1980-2009. According to the staged increase trend of global proved oil reserves during 1980-2009, the evolution process can be divided into five stages, and their characteristic time points could be selected correspondingly; then, the spatial rank distribution pattern and spatial organization of global oil resources at each time point can be discussed based on the function of spatial classification and visualization of ArcView GIS. The results are as follows. 1) The overall spatial distribution pattern of global oil resources can be characterized as irregular multi-centric layer structures, thereinto, Persian Gulf oil region and Mexico Gulf-Caribbean Sea oil regions are the two global oil poles in the Eastern and Western Hemispheres respectively, and their central roles were increasingly strengthened, while the other local oil regions, such as North American continent oil region, Caspian Sea oil region, Eurasia oil region, North Africa oil region, West Africa oil region, North Sea oil region and Java Sea oil region, experience different growth patterns. 2) The evolution of global distribution of oil resources is characterized as rise in the East and fall in the West, and the overall distribution pattern experienced an evolution process of diversification during 1980-1985, centralization during 1986-1990, re-diversification during 1991-1997, re-centralization during 1998-2001, and diversification again during 2002-2009, which eventually results in centralization in the North and diversification in the South. 3) The distribution space of oil resources in Western Hemisphere splited gradually into two layer structures with Venezuela and Canada as their reserve centers respectively, while four oil regions of North Africa, Persian Gulf, Caspian Sea and Eurasia lying through the mid-Eastern Hemisphere have been spatially joining together to form a huge crescent-like oil reserve belt, which could extend southward from Far East in the future.
  • Resources Evaluation
    ZHOU Bin, JIANG You-xu, ZANG Run-guo
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    The first time we defined the term of Gold Purchased by GDP (GPG) and regarded it as a new indicator of economic growth. GPG means the gold weight purchased by GDP according to the annual average exchange price and the annual average international gold price. Exploring the relationship between natural resource consumption and economic growth will contribute to improve the efficiency of resource utilization. This paper analyzed the data of commercial timber harvested, population, GDP and GPG of Southwest China since 1949, tested the hypothesis of Resource Curse and Kuznets Curve, the results showed: 1) with the increasing of GDP by 422 times from 1952 to 2008, the population, GPG and commercial timber harvested grew by one times, 4.5 times and 12 times respectively; 2) the commercial timber decreased by 80% resulted from the Natural Forests Protected Program from 1997 to 2000, but the figure of 9.5 million m3 in 2008 reached the level of 1997 and its increasing trend has not been changed since 1949; 3) the economic development experienced three GPG platforms and it stood at the third one currently. The linear correlation between GPG and timber consumption in the first 20 years was significant (P<0.01); 4) the per capita GPG increased by 1.5 times with the per capita GDP growing by 162 times. The linear correlation between commercial timber consumption and population was significant (P<0.01). The nonparametric correlation between GPG and population was true (P=0.005). The Resource Curse and Kuznets Curve did not exist between timber consumption and per capita GDP or per capita GPG; and 5) the commercial timber consumption per 10 thousand yuan or per kilogram GPG appeared inversed U-shaped curve, and the economic growth went through the period which has promoted by intensive labor and timber consumption.
  • Resources Evaluation
    HAO Jing-feng, LIU Hong-yu, LI Yu-feng, HU He-bing, AN Jing
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    Jiangsu Province is one of the dominant areas with broad coastal wetland which accounts for 14.2% of the whole coastal wetland in China, and moreover the yearly growth of the shoals are the important potential resources of Jiangsu. Coastal wetland landscape maps of the year 1987, 1997 and 2007 were figured from the three related maps. This study mainly investigates the spatio-temporal variation and driving forces of the coastal wetland resources of Jiangsu Province during 1987 to 2007 based on the remote sensing and GIS techniques and the method of conversion matrix. The results indicate: 1) in the past 30 years (from 1987 to 2007) the trend of evolvement of the coastal wetland was that the natural wetland transferred into artificial wetland. The natural wetland area decreased by 247.37km2 and 465.64 km2 respectively in the two periods(from 1987 to 1997 and from 1997 to 2007), while during the whole study period the artificial wetland and non-wetland areas increased by 204.01 km2 and 261.56 km2 respectively. The decrease of the natural wetland is mainly due to the remarkable reduction of reed-swamp and Suaeda-swamp while the Spartina-swamp was increasing as an invasive species during the whole study period. By 1997, the area of Suaeda-swamp had decreased by 33.38%, and the area of it in the year 2007 was just 7.10% of that in 1987. In the first period reed-swamp decreased by 37.97% with an overall decrease of 47.12% by 2007. The increase of the artificial wetland was mainly from the fish pond culture and during the study period it increased by 14.25%. The variations of the non-wetland were the increases in the cultivated land and residential land and the decrease of the forest land. 2) What influence the evolution of the coastal wetland resources of Jiangsu Province are the human activities and the invasive species. The factors of human activities are mainly about the national state policies, the expanding populations and the transfer of the industrial model. The expanding of the area of Spartina altemiflora was the vital natural driving force for the evolution of the coastal wetland resources of Jiangsu Province and the invasion of the Spartina altemiflora would restrain other ordinary species to survive. By 2007, the area of Spartina-swamp had increased by 71.94%, becoming a banding landscape in the coastal zone of Jiangsu Province.
  • Resources Evaluation
    TU Xin-jun, CHEN Xiao-hong
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    River runoff is a significant assessment index for surfer water resources. In this paper, based on the change-point theory and methods, the likelihood ratio method testing in the mean and the Schwarz Information Criterion testing in the variance, change points of time series of the river runoff such as the full year runoff, the flood season runoff, the dry season runoff, and the least monthly runoff are recognized for the main gauge stations of Guangdong Province from 1957 to 1999(hydrological year). Temporal and spatial locations of these tested change points are described in detail and key features of the characteristics variability of time series of the river runoff are concluded on the whole. In general, it is found that change point is widely tested in the existence of the dry season runoff and of the least monthly runoff, which annual runoff increases significantly and fluctuates remarkably after the change-point time, otherwise of the full year runoff and of the flood season runoff, and the change point location of these stations obviously occurred in 1972-1973 and 1981. Furthermore, change point in the mean of the dry season runoff happens in the Dongjiang Basin, and change point in the variance in the Beijiang Basin, the Hanjiang Basin, the Western Guangdong, and the Pearl River Delta. Change point in the mean of the least monthly runoff presents in the Dongjiang Basin and the Hanjiang Basin. Particularly, change point in the mean and in the variance are tested in the existence of these four kinds of annual series in the Sanshui station, the controlling gauge station of the Beijiang River flowing to the Pearl River Delta.
  • Resources Evaluation
    LIU Chao-shun, SHI Run-he, GAO Wei, GAO Zhi-qiang
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    Evaportranspiration(ET) of Shandong Province was assessed by MODIS satellite image coupling with meteorological data based on SEBAL model herein. It was revealed from the analysis results that ET derived from MODIS data was in very good agreement with the measurement by lysimeter and the calculation recommended by FAO Penman-Monteith method, with the consistency index of 0.917, correlation coefficient of 0.872, and daily relative error of about 11.34%. Further, the monthly and seasonal water budget of different land use/land cover types during 2005 and 2006 have been analyzed by coupling retrieved regional ET and spatial interpretation of precipitation. Results show that the total average of actual ET and precipitation during the month of March to November in the year 2005 were about 637.45 mm and 639.61 mm, respectively. The mean precipitation can almost meet the water consumption of ET. While in the year 2006, the actual ET and precipitation for the same period were respectively averaged 578.48 mm and 443.98 mm. The water loss reached 134.50 mm. It was also found that water deficit and drought were more serious in spring and autumn compared to that in summer.
  • Resources Research Methods
  • Resources Research Methods
    BAO Chao, FANG Chuang-lin, LIU Wen-hua
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    Restricted by the frail eco-environments and scarce water resources, the arid areas in Northwest China are crying for water transfer from rural to urban areas to accelerate the process of urbanization and industrialization. However, food security in the arid areas in Northwest China should also be guaranteed, and the rural and urban areas should both develop sustainablely with rational water reallocation. Consequently, it is urgent to find a way to resolve this problem. Zhangye City, which is located in the Heihe River Basin, is typical in the arid areas of Northwest China, was chosen as a case study. According to the problems Zhangye City are facing, such as low urbanization and industrialization level, low proportion of water utilization of the secondary and tertiary industries in the whole economy, low economic efficiency of water utilization and limitation of water supply for socio-economic system, the overall design of water utilization modes linked with urban and rural arid areas was made. Subsequently, five kinds of water utilization modes linked with urban and rural arid areas restricted by eco-environments were constructed, ie., increasing urban water use by returning farmlands to forests and grasslands with stable grain production, increasing urban water use by agricultural science and technology progress, transferring water from rural to urban use by agricultural industrialization, reusing urban reclaimed water in agriculture, and paying compensation when transferring water from rural to urban use. If these five kinds of water utilization modes are exercised together, it can help Zhangye City and the arid areas in Northwest China to innovate in water resources management and promote the rural and urban areas to develop harmoniously and rapidly.
  • Resources Research Methods
    PAN Jing-hu, LI Tian-yu
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    Land desertification has been a worldwide environmental problem. Desertification monitoring and evaluation is a very important content in desertification context. Scientific and accurate evaluation of desertification can provide scientific basis for decision-making in combating desertification. Because of the advantage of large amount of information, short cycle and broad scope of data, less restrictions on the human and material resources and so on,remote sensing has become an important technology to monitor land desertification in the past 30 years. Desertification is the most typical and serious form of desertification in China, especially in the oasis zone distributed along inland rivers or in the lower reaches of inland rivers in northwestern China. Quantitative evaluation of the current desertification remote sensing methods used are mostly obtained through the vegetation index and vegetation cover, to gain information on the extent of desertification. As the arid and semiarid sparse vegetation cover, soil and soil moisture on the most common vegetation index have a greater effect. Firstly, based on the SMA(Spectral Mixture Analysis)model,three kinds of endmember consisting of vegetation,water and bare soil were selected. The image dimensionality was reduced by the minimum noise fraction(MNF). The pixel purity index (PPI)transformation was used to narrow the range of the endmember. On the scatterplot of MNF,three kinds of endmember were selected, and relative abundance distribution of each component was obtained by using linear spectral mixture model. Secondly, a spectral feature space composed of vegetation component and land surface albedo retrieved from Landsat TM Imagery was constructed to evaluate desertification present condition and degree quantificationally. Finally, an empirical study was carried out taking the middle reaches of Heihe River as an example. Results indicated that this method makes full use of multi-dimensional remote sensing information, reflecting the desertification land cover, water, thermal environment and its changes,with a clear biophysical significance,and the index is simple, easy to obtain, high in precision, and is conducive to quantitative analysis, monitoring and assessment of desertification. It was rather ideal to assess desertification on the basis of Albedo-Vegetation feature space: correct prediction proportion of testing samples reached 90.3% and the prediction error of desertification degree was less than two grades. This method can be applied to the practical project.
  • Resources Research Methods
    QIU Bing-wen, SUI Yin-po, CHEN Chong-cheng
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    The characteristic scales in real landscapes reflect the spatial patterns and scales of human interactions with the environment. Identifying spatial structure and its characteristic scale is very important as well as necessary for exploring the spatial variability of different landscapes within remotes sensing images. Landscapes in mountainous area of South China is characterized as with strong variability and controlled by topographic conditions to a certain degree. Further researches are needed to quantitatively identify the characteristic scale of typical landscapes in those areas and its relationship with natural and anthropogenic processes. The prime objective of this study was to explore the characteristic scale of main landscapes at mountainous area in South China with semivariogram, wavelet transform and local variance using SPOT 10 m image. The first principal component of SPOT image is used for analysis. Results of variograms, wavelet variance, local variance for forest, city, agricultural and water landscapes all demonstrate that forest landscape possesses great spatial variability as quantified by the variogram or wavelet, local variance, and it partially originated from topographic complexity. City landscape also exhibits strong spatial variability and it's principally influenced by anthropogenic processes. Agricultural landscape is more heterogeneous than forest and city landscapes, but water landscape is most heterogeneous and no further variogram modeling conducted. Two different spatial structures were detected from wavelet analysis and semivariogram modeling in forest, city and agricultural landscapes individually. Results from variogram modeling are more precise and show that the range of the first spatial structure of city, agricultural and forest landscape is 16 m, 79 m and 95 m, and the second one is 133 m, 1031 m and 483 m respectively. Only one smaller characteristic scale is spotted from local variance. The mean characteristic scale quantified by mean length scale varies from 111 m to 569 m over city, forest and agricultural landscapes. The characteristic scale of forest in mountainous areas is relatively smaller than usual with the introduction of complicated landform. The largest spatial structure is detected in agricultural landscape which is the mosaic of agricultural crop fields surrounded by rivers and roads. In conclusion, a combined process for identifying characteristic scale with wavelet and semivariogram analysis is proposed. Firstly, wavelet method could be applied to distinguish the different spatial structures and the rough value of characteristic scale; then semivariogram modeling might be utilized to gain the exact value, with the number of combined models and parameters derived from results of wavelet analysis.
  • Special Forum
  • Special Forum
    ZHAO Xiao-feng, HUANG Xian-jin, CHEN Yi, CHEN Zhi-gang
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    Urban land intensive use is regarded as an important content for the research of urban land use change. Understanding the mechanism, process, and effects of urban land intensive use is helpful to optimize the urban spatial structure, improve the efficiency of urban land use, ease the pressure of urban development brought by resource and environmental constraints, and promote sustainable urban development. In this paper, scale, contents and methods which were presented in urban land intensive use research are concluded elaborately: 1) There are three kinds of scale in spatiality. Macro scale contains whole country, urban agglomeration and provinces; medium scale includes cities and functional region; while micro scale indicates parcel. Another scale is time which contains section data and panel data, and it maybe more valuable to analyse the variation and developing tendency of urban land intensive use with panel data. 2) As for the contents, connotation, theories, evaluation, driving forces, effects and approaches are mainly discussed in the literatures. Urban land intensive use has multifunctional and dynamic characteristics, and pays more attention to land use structure, land use intensity and land use efficiency. The evaluation of urban land intensive use is widely concerned, accordingly achieves considerable achievement, which mainly includes evaluation index system, spatial differentiation, comparisons between different industry trades and potential estimation. The driving forces of urban land intensive use are affected by spatial scales and time scales. The effects and approaches of urban land intensive use are weakly concerned, especially in China. 3) Some methods have been applied in researches, such as statistic analysis, econometric analysis, dynamic process model and spatial analysis. In addition, PSR model, DPSIR model and life cycle assessment are also helpful to the research. Although much progress has been made in theory and practice of urban land intensive use research, and some important results have been obtained, there still have certain problems in previous researches. Some suggestions which help to develop the research are as follows: Firstly, multi-level, multi-scale and time series research should be adequately emphasized to realize characteristics of urban land intensive use. Secondly, the theoretical foundation, intrinsic mechanism, dynamic process and comprehensive effects should be studied deeply. Lastly, econometric analysis, dynamic process model and spatial analysis should be applied extensively.