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Table of Content

    20 March 2012, Volume 27 Issue 3 Previous Issue    Next Issue
    Resources Utilization and Management
    Management Efficiency and Participatory Mechanism of Farmland Water Conservancy in China: An Empirical Analysis Based on Stochastic Frontier Approach
    ZHANG Ning, LU Wen-cong, DONG Hong-ji
    2012, 27 (3):  353-363.  doi: 10.11849/zrzyxb.2012.03.001
    Abstract ( )   PDF (680KB) ( )   Save
    In order to improve the management efficiency of water resource in China, and realize a reasonable collocation of irrigated water resources, the farmland water conservancy management is an important means to achieve the agricultural water saving and using. The research is based on the stochastic frontier production function to evaluate the management technique efficiency of water conservancy, and select the linear inefficient regression and Logistic model to explain the participatory mechanism which influences more obviously water management efficiency. The result shows that the management efficiency of water conservancy in China has yet to be improved to a large extent. The level of water management efficiency differs in different economic and natural regions as well as different management modes adopted. Increasing non-collective property, establishing water fee system and improving farmer's participation could contribute to the improvement of the efficient use of agricultural water resources. The research results can help different regions construct a suitable farmer's participatory mode and promote continuous use of agricultural water in China, which all have a great practical significance and reference value.
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    Wind Energy Resources Assessment in Global Ocean
    ZHENG Chong-wei, PAN Jing
    2012, 27 (3):  364-371.  doi: 10.11849/zrzyxb.2012.03.002
    Abstract ( )   PDF (652KB) ( )   Save
    In this paper, wind energy resources in global ocean from January 1988 to December 2009 were analyzed by using high resolution CCMP (Cross-Calibrated, Multi-Platform) wind field. By synthetically considering the size of wind energy density, the frequency of energy level, scale frequency, effective wind speed and the stability of energy density, the resources of wind energy in global ocean were analyzed and zonation was conducted, providing guidance to wind power plant location. Results show that the global ocean is rich in wind energy, with rich areas located in the waters of westerlies of the Northern Hemisphere and the Southern Hemisphere, poor areas mainly distributed in the waters nearby the equator and scattered sectors of the two poles, and the sub-rich area located in the waters of low latitude, eastern sector of the low latitude in the Pacific Ocean, and most waters of the two poles.
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    Analysis on Decision-making Mechanism of Farmer Household in Sangong River Watershed on Logistic Model
    ZHU Hui, ZHANG Xin-huan, JIAO Guang-hui, WANG Zhe
    2012, 27 (3):  372-381.  doi: 10.11849/zrzyxb.2012.03.003
    Abstract ( )   PDF (920KB) ( )   Save
    This paper, based on survey data of 27 administrative villages and 240 households around Sangong River Basin in Xinjiang (the companies),through the establishment of farmers' willingness to grow oil crops and logistic regression variables and measurement models, analyses influential factors of farmers planting willingness from factors of household characteristics,factors of resource endowments,factors of household economy and other 13 factors in four major oil crops producing areas.Studies have shown that: the total household population,the agricultural technology service attitude and farmers planting willingness are positively correlated,and the attitude of the standardization coefficients of agricultural technology service factor has more significant impact; the annual number of employed in agriculture, education level and block-headed are negatively correlated, and the greater the cultural level of the head of the household's standardized coefficient, the greater the impact. However,reflection of the land input into the farm family economy,farming income,and per capita income does not pass inspection,it can not gain the relationship between these variables and farmers' willingness to grow oil crops.Finally,the article discusses the differences of impact on farmers' willingness between companies and administrative villages.
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    Resources Ecology
    River Ecosystem Response of Impervious Surface in River Network City: A Framework of Methodology
    ZHAO Jun, SHAN Fu-zheng, XU Yun-feng, QIAN Guang-ren
    2012, 27 (3):  382-393.  doi: 10.11849/zrzyxb.2012.03.004
    Abstract ( )   PDF (601KB) ( )   Save
    The rapid expanding of impervious surface in river network city has became a more and more important factor effecting the river ecosystem health, so understanding the pressure response relationship between the impervious surface and river ecosystem is of fully necessary. The international research history of impervious surface and its effect on river ecosystem has already past 40 years, and perfect theory and method system has already established, however, our current research is still at its initial stage. Focusing on overseas research, this paper reviews the main advances of impervious surface as the following three aspects: firstly the identification technical approach of impervious surface, then the pressure response relationship between river basin impervious surface and river ecosystem conditions, finally the application of impervious surface threshold in river basin land use planning regulation and river management, in particular a detailed analysis on the threshold effect of impervious surface is summarized in literature from 1960s. From four aspects including the research perspective, research methods, study area and decision-making applications, the current problems in the literature was diagnosed. Considering the special hydro-geomorphic characteristics of river network area, this paper puts forward the main task in river network city, propose methods to solve the key technical issues advanced by the authors, such as the field survey of impervious surface and how to transition it to effective impervious surface, the hydrological units and its multi-scale system, pressure response system, as well as the data analysis methods and so on. Finally, the typical river network city Shanghai was taken as a case, and at riparian scale the relationship between impervious surface and river ecosystem was detected, in which the result showed there was an obvious non-linear relationship. The framework in this paper would be expected to provide methodology references for forwarding empirical investigations.
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    Effects of Carbon Emission by Land Use Patterns in Hefei's Economic Circle of Anhui Province
    SUN Xian-bin
    2012, 27 (3):  394-401.  doi: 10.11849/zrzyxb.2012.03.005
    Abstract ( )   PDF (756KB) ( )   Save
    Land use change is an important factor for carbon emission. According to the assessment model and by using the Landsat TM data separately acquired in 1997 and 2007 on the economic circle of Hefei, the provincial capital of Anhui, the authors utilized data of land use types such as cultivated land, woodland, grassland and land for construction in 1997 and 2007 to calculate carbon emissions and the compensation standard based on price of fixation carbon dioxide. The results shows: 1) Carbon emissions greatly varied over different land use types, in which the land for construction and cultivated land were considered as two major carbon sources. Woodland and grassland were two major carbon sinks. Carbon emissions were found to increase by 14.4% per year over the entire economic circle of Hefiei from 1997 to 2007. Carbon emissions increased most quickly in the city, with an average annual growth rate of 32.3% during the ten years. With more impacts of human activities, carbon emission from land for construction was the highest, increased from 7.4587 million tons in 1997 to 17.9409 million tons in 2007. However, carbon sink maintained generally stable during this period. 2) Two indexes describing carbon emissions, i.e., carbon emission per unit area of land and carbon emission per unit area of construction land, were proposed. These two indexes could better reflect carbon emission intensity from 1997 to 2007 and the differences among the regions. Compared with carbon emission intensity in 1997, the two indexes increased by 1.18 and 1.41 times in 2007, respectively. Carbon emissions peaked in Hefei city, and showed a relatively higher level in Chaohu city and a low level in Lu'an city, and the index of carbon emission per unit area of land and construction land indicated the same changing trend. 3) Carbon emission per unit area of land was markedly different in 15 counties or urban areas, and the three largest ones per unit area of construction land are urban area of Hefei city, Huoshan and Jinzhai counties. 4) On the basis of carbon emission and price of fixation carbon dioxide over the provincial city economic circle during the period 1997-2007, the value of the standard for ecological compensation in three cities was estimated. Based on average cost of tree planting in China, an increasing amount of the compensation standard for the three cities was 2.183, 0.431 and 0.248 billion yuan respectively, and the amount of compensation standard was different among counties or urban areas. 5)There was certain relationship between land use structure and carbon emissions. Some suggestions for reducing carbon emissions were put forward.
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    Spatial Fuzzy Assessment of Ecological Suitability for Urban Land Expansion Based on Variable Weights: A Case Study of Taicang
    SHU Bang-rong, HUANG Qi, LIU You-zhao, LI Yan, YAN Chang-qing
    2012, 27 (3):  402-412.  doi: 10.11849/zrzyxb.2012.03.006
    Abstract ( )   PDF (962KB) ( )   Save
    Assessment of ecological suitability for urban land is playing an increasingly important role in urban planning because much more pressures on regional ecosystem are put by urban expansion, which has met the needs of regional economic development. Though great achievements have been made in related researches, constant weight assessment, as normally used method, should be substituted because it possibly gets unscientific results due to the neutralization of excellent indicators and bad ones. However, the theory of variable weights proposed by Wang Peizhuang could help to overcome those problems by considering the relationship of all indicators and enhance the impacts of prominent indicators. Therefore, based on the local punishment model of variable weights, the paper presents a method of spatial fuzzy comprehensive assement in order to settle the problems of traditional methods and to reflect the characteristics of fuzziness and spatial accuracy. The evaluation index system is established by choosing seven indexes which have influence on ecological suitability for urban expansion, and a case study in Taicang city was taken under the support of GIS software, so as to guide the urban land expand rationally.It is found that the model of variable weights could calculate the weights of various indexes of every grid flexibly and reasonably, thus make initial weights of different indexes change diversely according to relationship of all indexes of different grid units. Take the index of "distance to coastline of the Yangtze River and reservoir" as an example, the index weights in different locations change from 0.0388 to 0.5774, and the weights in the locations of the Yangtze River and reservoirs reach to 0.5774, which is 198.86% higher than initial weight (0.1932), so the index could increase the comprehensive value of ecological sensitivity for urban land expansion of those grids. According to the result of ecological suitability assessment, the study area was divided into four types: suitable land, moderately suitable land, little unsuitable land and unsuitable land. The area of each type respectively is 20871.09, 6727.41, 30169.71 and 22836.51 hm2, which is 25.89%, 8.35%, 37.43% and 28.33% of the study area accordingly. Moreover, the result of ecological sensitivity value also shows that the values of the grid units range from 0 to 8.9570, and their spatial distribution accords with the fact. The study indicates that the method of spatial fuzzy comprehensive assessment based on variable weights theory could not only make scientific evaluation on the ecological suitability for urban land expansion from microcosmic and spatial perspectives, but also highlight the importance of restrictive factors and make the vetoes of bottleneck factors effective, thus it could reflect the land ecological suitability status for urban expansion more accurately and reasonably. So it is of great help to provide a scientific basis for decision-making in urban planning and land use planning.
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    Main Crops Structural Change and Its Climate Background in Gansu Province during the Past Two Decades
    WANG He-ling, WANG Run-yuan, ZHANG Qiang, LIU De-xiang, PU Jin-yong
    2012, 27 (3):  413-421.  doi: 10.11849/zrzyxb.2012.03.007
    Abstract ( )   PDF (643KB) ( )   Save
    Global warming during the 20th century, especially the impacts of the global warming in the past two decades has been paid much attention worldwide. A case study is made in this paper on the relationship between change of main crops structure and global warming in Gansu Province of Northwest China based on the statistical data of agriculture and ground based climate data during 1985 to 2005. The results showed that in the past 20 years, especially in 1990s, in Hexi Corridor corn and cotton sown area expanded obviously, the proportion of cotton and corn sown area increased significanly, but the proportion of the spring wheat dropped rapidly and retreat extensively to the Qilian shallow mountain region, corn and cotton gradually replaced the wheat in Hexi Corridor and became the main crops. In the central region, the sown area of spring wheat reduced year by year, and winter wheat planting area expanded, the proportion of maize increased year by year also, potato planting scale increased gradually; in the southeastern region, winter wheat and spring wheat planting area decreased year after year, but corn, winter oilseed rape and other cash crops increased year by year. Under global warming, it is proved that temperature change has influenced human society to a certain extent and people began to adapt to the new environment by transferring the land use patterns.
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    The Effect of Land Use Patterns on Soil Moisture Retention Capacity and Soil Infiltration Property in Eastern Qilian Mountains
    ZHAO Jin-mei, ZHANG De-gang, LIU Chang-zhong
    2012, 27 (3):  422-429.  doi: 10.11849/zrzyxb.2012.03.008
    Abstract ( )   PDF (700KB) ( )   Save
    The effect of land use patterns on the soil moisture retention capacity and soil infiltration property in Tianzhu, the alpine area in the eastern Qilian Mountains, was studied. The four land use patterns were selected in the experimental area, including natural grassland, naturally restored abandoned cropland, oats and sowed perennial grassland. The results showed that there existed significant differences in soil moisture retention capacity and soil infiltration property among the four types of land use patterns. The soil bulk density from high to low was returned farmland to naturally restorated grassland (1.104 g/cm3)>sowed perennial grassland (1.061 g/cm3)>oats (1.011 g/cm3)>natural grassland (0.781 g/cm3); the soil total porosity from high to low was natural grassland(68.196%)>oats (60.606%)>sowed perennial grassland (58.93%)>returned farmland to naturally restorated grassland (57.5%); total water holding capacity and infiltration rates of the soil of natural grassland was the largest(681.966 t/hm2, 3.02 mm/min), while the total water holding capacity and infiltration rates of returned farmland to naturally restorated grassland was the lowest (575.005 t/hm2, 1.004 mm/min). In general, the soil of the natural grassland has the best hydrological function in soil water retention capacity and infiltration property. These characteristics are better in the oats and sowed perennial grassland, while the performance of the returned farmland to naturally restorated grassland is the worst in four aspects.
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    Soil Organic Carbon Accumulation and Distribution in a Small Watershed and the Effects of Soil Water
    ZOU Jun-liang, GUO Sheng-li, LI Ze, ZHANG Fang, ZHANG Yan-jun, ZHOU Xiao-gang, NAN Ya-fang
    2012, 27 (3):  430-439.  doi: 10.11849/zrzyxb.2012.03.009
    Abstract ( )   PDF (545KB) ( )   Save
    The spatial distribution patterns of soil water and Soil Organic Carbon(SOC) caused by topography and land use provide opportunities to study the coupling of water and carbon of the terrestrial ecosystem. It can help us better understand the contribution of soil water to SOC accumulation and distribution at a watershed scale, but the strong variability of soil water and relative stability of SOC bring new challenges for the work. Thereafter, a resampling approach was used to assess soil water and SOC after rainy season based on the continental water balance. Totally 37 plots covering three different landforms and three different land uses were sampled 100 cm below surface soil using a 3 cm diameter auger. When compared under the same land use, generally soil water and SOC of valley bottom was higher than ridge slope, while gully slope was intermediate; but the water-carbon transferring efficiency presented an inverse order. Under the same landform, soil water and SOC of different land uses had the opposite order, when farmland owned the highest water content, its SOC was the lowest; the same occurred at grassland and woodland. Both the woodland and grassland could transfer water to carbon faster compared to farmland. There was a positive relationship fitted well by an exponential growth model (y=y0+log a×ax) between SOC and soil water. Soil water could partially (7%-37%) explain SOC accumulation and distribution in the small watershed. This would be very crucial for the prediction of SOC accumulation and distribution based on soil water variability.
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    Research on Water-Consumption Characteristics of Calligonum arborescens under Different Irrigation Amounts
    SHAN Li-shan, LI Yi, ZHANG Xi-ming, WANG Hui
    2012, 27 (3):  440-449.  doi: 10.11849/zrzyxb.2012.03.010
    Abstract ( )   PDF (524KB) ( )   Save
    As a primary limiting factor affecting survival and growth of plants, moisture has important effects on water physiological characteristics. We studied water-consumption characteristics in the Tarim Dersert Highway Protection Forest to provide some references for local irrigative management. The heat-balance stem flow gauge was used to measure water physiological characteristics of Calligonum arborescens under different irrigation amounts (17.5, 28 and 35 kg·plant-1 once a time). The results showed that: the diurnal variation curve of stem sap flow of C.arborescens varied with irrigation amounts, when irrigating 35 and 28 kg·plant once a time, the diurnal variation of stem sap flow presented unimodal curve and the sap flow rate were higher; as for irrigating 17.5 kg·plant-1 once a time, the diurnal variation changed in two-peak curve and the sap flow rate was small, which caused stress. With irrigation amounts reduced, the predawn and midday water potential of C.arborescens all gradually decreased at the same time and the more severe climatic conditions and the less irrigation, the more significant water potential decrease. The water potential of July was the least under different irrigation amounts during the growing season. The daily water consumption was decreased with reducing irrigation amounts at the same time; the daily water consumption of July was the most under different water treatments. It can be seen that the C. arborescens adapts to the environment by coordinating water balance. Considering the stabilization of protection forest and water resources, the current irrigation volume of protection forest in the Tarim Desert Highway should be reduced, but it can not be lower than 17.5 kg·plant-1 once a time, this will satisfy the water demand of C. arborescens, and also maintain the stabilization of protection forest.
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    Modeling Light Use Efficiency of an Alpine Meadow on Northern Tibetan Plateau Using Evaporative Fraction and Air Temperature
    FU Gang, SHEN Zhen-xi, ZHANG Xian-zhou, SHI Pei-li, HE Yong-tao, SUN Wei, WU Jian-shuang, ZHOU Yu-ting
    2012, 27 (3):  450-459.  doi: 10.11849/zrzyxb.2012.03.011
    Abstract ( )   PDF (771KB) ( )   Save
    Light use efficiency (LUE) is defined as the ratio of primary production and absorbed light energy by vegetation canopy. The quantifying modeling of primary production is based on the quantifying modeling of LUE. A light use efficiency model developed from eddy covariance (EC) measurements, called EC-LUE, was used to model LUE of alpine meadows on Northern Tibetan Plateau in 2004-2005. The EC-LUE is driven by evaporative fraction (EF) and air temperature (Ta). EF and Ta were the water attenuation scalar (Wscalar) and temperature attenuation scalar (Tscalar) of maximum light use efficiency (LUEmax), respectively. In this study, LUEmax was set to be 0.85 g C/MJ. The integrated attenuation effect of Tscalar and Wscalar on LUEmax could be multiplied or following the Liebig's law. The LUE values simulated by the two approaches were labeled by LUEmultipEC and LUEminEC. The LUE derived from eddy covariance measurements was labeled by LUEEC. The LUEminECwas significantly larger than LUEEC, but the difference between LUEEC and LUEmultipEC was not significant. LUEmultipEC and LUEminEC explained both significantly above 89% seasonal changes of LUEEC. EF significantly explained soil water content (SW) at the depths of 0.05 m and 0.10 m, and specific humidity. Besides, EF also explained relative humidity to some extent. Compared to Wscalar, Tscalar might explain more seasonal variations of LUE based on correlation analysis and multiple stepwise linear regression analysis. Therefore, EC-LUE model could quantify the seasonal change of LUE and EF could quantify the seasonal change of environmental water for alpine meadows.
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    Resources Evaluation
    The Application of a New Model in Intensive Use Evaluation of Agricultural Land
    HE San-wei, PAN Peng, ZHU Yun-qiang, CHEN Peng-fei
    2012, 27 (3):  460-467.  doi: 10.11849/zrzyxb.2012.03.012
    Abstract ( )   PDF (459KB) ( )   Save
    As a large agricultural nation, China is faced with low efficiency of agricultural land use and sharp reduction of the quantity of agricultural land. It is urgent to alleviate the relationship between population and land, and improve the efficiency of agricultural land intensive use when China embarks on solving problems of agricultural land. Therefore, it reveals great significance to evaluate the intensive use of agricultural land. Taking Shaanxi Province as an example, the dynamic fuzzy neural network is applied to evaluate the intensive use of agricultural land in order to overcome the low learning process and rule disasters existed in traditional methods. Aiming to improve the accuracy of evaluation, combination of qualitative and quantitative analysis is used to select evaluation index system without high level of redundancy through eliminating cropland balancing index and labor force per hm2 quantitatively and the model receives fine convergence without exceeding 3×10-16 in errors. In order to analyze evaluation results, evaluation scores obtained from the new model are clustered into four classes using the K-means method. Compared with the actual situation of agricultural land intensive using, the results reveal that intensive degrees of agricultural land distribute with spatial division in accordance with actual situations in Shaanxi and Yangling is the highest in intensive degrees of agricultural land. Finally, intensive degrees of agricultural land and per capita net income of farmers have positive significance correlation through stepwise regression analysis. The correlation coefficient is 0.74, and is higher than intensive degrees and GDP per capita and urbanization degrees, coming to a conclusion that per capita net income of farmers is the primary factor of affecting intensive degrees of agricultural land.
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    Evaluate to Water Resources Vulnerability Using SWAT-WEAP Model in Tributary of Xiliaohe River
    HAO Lu, WANG Jing-ai
    2012, 27 (3):  468-479.  doi: 10.11849/zrzyxb.2012.03.013
    Abstract ( )   PDF (640KB) ( )   Save
    The impact of climate change and human activities on the water cycle and water security are the new areas of research directions and a topical issue within international hydrological science in the 21st century. Laohahe River Basin (LRB) was selected as the research area. Used the coupling hydrological model method (SWAT-WEAP), the hydrology simulated by the Soil and Water Assessment Tool (SWAT) was used to drive Water Evaluation and Planning System (WEAP) for simulating water demand and supply under potential future climate change scenarios based on the framework of "climate change-water resources-environment-society and economy". Water vulnerability is the degree to which a water system is susceptible to, or unable to cope with, adverse effects of climate change, including climate variability and extremes. Water vulnerability is a function of the character, magnitude and rate of climate variation to which a water system is exposed, its sensitivity, and its adaptive capacity. The unmet water demand was applied to the vulnerability index (VI) to quantitatively analyze the water vulnerability to the climate and human activities change. The results show that: 1) predicted temperature increase 2 ℃ together with a 10% reduction in precipitation has a disproportionately greater impact on the vulnerability of water resources, that is, warm and dry weather increased significantly the vulnerability of water resources in LRB. 2) The impact of climate change on irrigation water shortage is greater than on domestic and industrial water shortage. 3) The main problem in the area is caused by number of identified water uses in agriculture sector, which is the driving force in the area. Over irrigation is a strong constraint to the integrated water resource management. The main problem is not the shortage of water but the management of the lake. To develop animal husbandry, change planting structure, and increase the efficiency of water-saving irrigation are the most effective measures to adapt to climate change. 4) In most scenarios, warm and dry climate intensifies and aggravates the impact of human activities on water resources vulnerability. Reservoir can effectively reduce the vulnerability of water resources. However, the effectiveness of such conventional supply-oriented measures weakens due to limited water supply source in dry and warm climate. In short, the impact of climate change on water resources not only depends on the river runoff and groundwater recharge volume, changes in the allocation of time, but also depends on the characteristics of the water system, the pressure changes of water system, and what kind of system management and measures are in place to adapt to climate change. Non-climate change factor may have a greater impact than climate change factor on water resources vulnerability.
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    A Study on Content and Balance of Moisture in the Southern Tengger Desert
    ZHAO Jing-bo, XING Shan, SHAO Tian-jie, DONG Zhi-bao, YU Ke-ke, YUE Ying-li, CHEN Bao-qun
    2012, 27 (3):  480-488.  doi: 10.11849/zrzyxb.2012.03.014
    Abstract ( )   PDF (837KB) ( )   Save
    In order to reveal sand moisture content, water movement and balance of the Tengger Desert, the moisture content of different types of dunes in Minqin and Zhongwei was studied. The results show that the spatial variation of sand moisture content is remarkable. The layered structure is clear in vertical direction while the moisture content of mobile dune is higher than that of half-fixed dune and fixed dune in horizontal direction, and the moisture content of southeastern edge of the desert is higher than that of southwestern. The phenomena, which the higher moisture content lies the upper part in Minqin and above capillary water sand layer in Zhongwei, indicate the sand moisture mainly comes from meteoric water. The moisture form is mainly film water in this area. There is high moisture content of film water in the southeastern edge of the Tengger Desert, which has more precipitation. The characteristic of sand moisture is special positive equilibrium, which is defined by water physical properties of sand layer. It can correctly explain why there are many lakes and abundant groundwater in the extreme dry desert. This paper also presents two modes of water movement.
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    Spatial Pattern of Urban Land Use in the Mountain Area: A Case Study of Liupanshui in Guizhou Province
    MA Shi-bin, ZHANG Yong-rong, AN Yu-lun
    2012, 27 (3):  489-496.  doi: 10.11849/zrzyxb.2012.03.015
    Abstract ( )   PDF (585KB) ( )   Save
    Based on the following remote sensing satellite images: TM images obtained in 1990, ETM images in 2000 and CBERS 02B images in 2010, with the terrain niche index and distribution index, using human-computer interactive interpretation and the spatial overlay analyst of Geographical Information System, the land use variation data of Liupanshui Prefecture in Guizhou Province from 1990 to 2010 was obtained and its spatial distribution characteristics were quantitatively analyzed. The results showed that: 1) The spatial distribution of various land use types changed definitely during the two decades: the superiority of construction land in lower terrains increased and it had a trend of extending to higher terrains; the superior distribution range of paddy fields decreased to sections 1-7 from setions 1-9 but its superiority in low terrains increased; as a result of the increase of the superiority of construction land and paddy fields in low terrains, the superior distribution region of dry crop land and shrub land diminished and shifted up one or two sections. 2) During the 20 years, the whole spatial distribution pattern of land use in the study area did not change obviously, the terrain niche index curve still kept its three-section model; various land use types distributed alternatively, the obvious concentric ring and zonal distribution pattern centered on construction land was not formed. 3) Because of the particular geological environments in the study area and the contradiction relationship between human and land, the terrain suitability elastic of land use types partly intervened by human beings was stretched, which made the spatial distribution of some land use types such as dry crop land and construction land violated its natural quality, they appeared in higher terrain sections and had the trend of shifting up to higher sections.
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    Resources Research Methods
    Simulation on Optimized Allocation of Land Resource Based on GECM and CA+ANN Model
    ZHENG Rong-bao, DONG Yu-xiang, CHEN Mei-ying
    2012, 27 (3):  497-509.  doi: 10.11849/zrzyxb.2012.03.016
    Abstract ( )   PDF (620KB) ( )   Save
    Optimal allocation of land resources is becoming a hot spot in land scientific research. Based on the results of previous studies, the authors build up the model of the Gradual Easy Constraint Method (GECM) with the multi-objective dynamic programming method. This model aims on social, economic and ecological benefits, and sets up eight aspects as GECM constraints to research on the optimized allocation of land use structure in Huadu District in 2020. Then through the results of structural optimization as constraints, we can use the artificial neural networks and cellular automata (ANN+CA) model to simulate and predict the change of land use from 2008 to 2020. The results indicate that: 1) GECM is a good method on land use structure optimization research, the built-up area in 2008 (23097 hm2) will reach the rational level in 2020 (28800 hm2), and this district must select the direction of land intensive use in the future years. 2) CA+ANN can achieve the target of spatial allocation and simulation on land resources. Coupling with GECM and ANN+CA models, the research results are more suitable and reasonable to the actual situation in Huadu District. It also can achieve the unity of time and space in optimal allocation of regional land use.
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    Characteristics of Water Vapor Transportation and Budget over the Heihe Drainage Basin
    LU Gui-hua, XU Dong, HE Hai
    2012, 27 (3):  510-521.  doi: 10.11849/zrzyxb.2012.03.017
    Abstract ( )   PDF (870KB) ( )   Save
    Based on the NCEP/NCAR re-analysis daily mean data from 1948 to 2008, the characteristics of water vapor transportation and budget over the Heihe Drainage Basin were analyzed in this passage. The results showed that, influenced by westerly circulation, Atlantic and Arctic oceans were the main water vapor source over the Heihe Drainage Basin. Water vapor was mainly latitudinally transported from west to east, and the intensity of water vapor exported from east boundary of the Heihe Drainage Basin was greater than that imported from west boundary, the intensity of water vapor imported from north boundary was also greater than that exported from south boundary. In the layer of 700 hPa, convergence and divergence of the southern Heihe Drainage Basin changed seasonally, it is a water vapor divergence area in winter, but a convergence area in summer. The northern Heihe Drainage Basin had no such obvious characteristics all the year round. The annual influent water vapor amount is about 997.3 km3, effluent water vapor amount is about 1046.1 km3, and the net water vapor amount is about 48.8 km3. The net water vapor amount tended to increase since the 1960s. Water vapor in the northern desert area of the Heihe Drainage Basin exported whole year, and it mainly exported from middle and lower atmosphere (surface to 500 hPa). June to September was the water vapor net influent period in the southern mountain area of the Heihe Drainage Basin, and lower atmosphere (surface to 700 hPa) was the main influent layer, middle and upper atmosphere (700 to 300 hPa) was the main enffuent layer. Annual evaporation amount is about 84 km3 according to the atmospheric water balance.
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    Special Forum
    The Origin, Characteristics and Prospect of Fishing Quota Legal System
    BAI Yang
    2012, 27 (3):  522-528.  doi: 10.11849/zrzyxb.2012.03.018
    Abstract ( )   PDF (399KB) ( )   Save
    Fishing quota legal system is an output control management based on ecological characteristics of fisheries resources, which the historical background is over-fishing and input control management failed. It is the development basis for TAC (total allowable catch), and is successfully implemented in Iceland and New Zealand. The system is exclusive, sustainable, transferable and incentive in the layer of law. Scholars have different views for the legal characteristics of quotas, of which the quasi-property was approved by majority. Its resources attribute essentially decides the quotas system which is a common duty that cannot overpass the total allowable catch. Through the implementation of a limited access, deepening international cooperation and strengthening the supervision means, we could secure mutual obligations, and then realize the sustainable utilization of resources.
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