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    2012年, 第22卷, 第2期 刊出日期:2012-03-05 上一期    下一期
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    论文
    Spatial Scale Effects of Water Erosion Dynamics: Complexities, Variabilities, and Uncertainties
    WEI Wei, CHEN Liding, YANG Lei, FU Bojie, SUN Ranhao
    2012 (2):  127-143. 
    摘要 ( 1158 )   PDF(1374KB) ( 2168 )  

    Severe water erosion is notorious for its harmful effects on land-water resources as well as local societies. The scale effects of

    water erosion, however, greatly exacerbate the difficulties of accurate erosion evaluation and hazard control in the real world. Analyzing

    the related scale issues is thus urgent for a better understanding of erosion variations as well as reducing such erosion. In this review

    article, water erosion dynamics across three spatial scales including plot, watershed, and regional scales were selected and discussed.

    For the study purposes and objectives, the advantages and disadvantages of these scales all demonstrate clear spatial-scale

    dependence. Plot scale studies are primarily focused on abundant data collection and mechanism discrimination of erosion generation,

    while watershed scale studies provide valuable information for watershed management and hazard control as well as the development of

    quantitatively distributed models. Regional studies concentrate more on large-scale erosion assessment, and serve policymakers and

    stakeholders in achieving the basis for regulatory policy for comprehensive land uses. The results of this study show that the driving

    forces and mechanisms of water erosion variations among the scales are quite different. As a result, several major aspects contributing

    to variations in water erosion across the scales are stressed: differences in the methodologies across various scales, different sink-

    source roles on water erosion processes, and diverse climatic zones and morphological regions. This variability becomes more complex in

    the context of accelerated global change. The changing climatic factors and earth surface features are considered the fourth key reason

    responsible for the increased variability of water erosion across spatial scales.

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    Runoff Change of Naoli River in Northeast China in 1955–2009 and Its Influencing Factors
    SONG Xiaolin, LU Xianguo, LIU Zhengmao, SUN Yonghe
    2012 (2):  144-153. 
    摘要 ( 1618 )   PDF(577KB) ( 1185 )  

     Runoff change and trend of the Naoli River Basin were studied through the time series analysis using the data from the

    hydrological and meteorological stations. Time series of hydrological data were from 1957 to 2009 for Bao′an station, from 1955 to 2009

    for Baoqing station, from 1956 to 2009 for Caizuizi station and from 1978 to 2009 for Hongqiling station. The influences of climate change

    and human activities on runoff change were investigated, and the causes of hydrological regime change were revealed. The seasonal

    runoff distribution of the Naoli River was extremely uneven, and the annual change was great. Overall, the annual runoff showed a

    significant decreasing trend. The annual runoff of Bao′an, Baoqing, and Caizuizi stations in 2009 decreased by 64.1%, 76.3%, and 84.3%,

    respectively, compared with their beginning data recorded. The wet and dry years of the Naoli River have changed in the study period.

    The frequency of wet year occurrence decreased and lasted longer, whereas that of dry year occurrence increased. The frequency of

    dry year occurrence increased from 25.0%–27.8% to 83.9%–87.5%. The years before the 1970s were mostly wet, whereas those after

    the 1970s were mostly dry. Precipitation reduction and land use changes contributed to the decrease in annual runoff. Rising temperature

    and water project construction have also contributed important effects on the runoff change of the Naoli River.

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    Impact Factors on Distribution and Characteristics of Natural Plant Community in Reclamation Zones of Changjiang River Estuary
    SUN Yongguang, LI Xiuzhen, HE Yanlong, JIA Yue, MA Zhigang, GUO Wenyong, XIN Zaijun
    2012 (2):  154-166. 
    摘要 ( 1219 )   PDF(821KB) ( 1403 )  

    To identify impact factors on the distribution and characters of natural plants community in reclamation area, with survey data from 67 plant quadrats in July 2009, soil properties data from 216 sampling points in April 2009, and TM (30 m) data in 2006, the composition and characteristics of natural plants community in different time of the Fengxian area in the Changjiang (Yangtze) River estuary were analyzed with two-way indicator species analysis (TWINSPAN), multivariate analysis of variance (MANOVA), detrended canonical correspondence analysis (DCCA) and canonical correspondence analysis (CCA). The results show that: 1) The plant communities in the reclaimed area are mainly mesophytes and helophytic-mesophytic transitional communities, showing a gradient distribution trend with the change in reclamation years. Species richness (MA), species diversity (H) and above-ground biomass also increase with the increase of reclamation years. Nevertheless, they appear to decline slightly in the middle and late reclamation period (> 30 years). 2) With the rise in land use levels, the changes in species richness and species diversity tend to increase at first and then decrease; species dominance (D), however, tends to decline; and above-ground biomass increases slightly. 3) The distribution of the plant community is mainly influenced by the following factors: land use levels (R = 0.55, p < 0.05), soil moisture (R = 0.53, p < 0.05), soil salinity (R = 0.43, p < 0.05) and reclamation time (R = 0.40, p < 0.05).

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    Restoration and Rational Use of Degraded Saline Reed Wetlands:A Case Study in Western Songnen Plain, China
    WEN Bolong, LIU Xingtu, LI Xiujun, et al
    2012 (2):  167-177. 
    摘要 ( 850 )   PDF(568KB) ( 1322 )  

    The protection, restoration and sustainable use are key issues of all the wetlands worldwide. Ecological, agronomic, and engineering techniques have been integrated in the development of a structurally sound, ecologically beneficial engineering restoration method for restoring and utilizing a degraded saline wetland in the western Songnen Plain of China. Hydrological restoration was performed by developing a system of biannual irrigation and drainage using civil engineering measures to bring wetlands into contact with river water and improve the irrigation and drainage system in the wetlands. Agronomic measures such as plowing the reed fields, reed rhizome transplantation, and fertilization were used to restore the reed vegetation. Biological measures, including the release of crab and fish fry and natural proliferation, were used to restore the aquatic communities. The results of the restoration were clear and positive. By the year 2009, the reed yield had increased by 20.9 times. Remarkable ecological benefits occurred simultaneously. Vegetation primary-production capacity increased, local climate regulation and water purification enhanced, and biodiversity increased. This demonstration of engineering techniques illustrates the basic route for the restoration of degraded wetlands, that the biodiversity should be reconstructed by the comprehensive application of engineering, biological, and agronomic measures based on habitat restoration under the guidance of process-oriented strategies. The complex ecological system including reeds, fish and crabs is based on the biological principles of coexistence and material recycling and provides a reasonable ecological engineering model suitable for the sustainable utilization of degraded saline reed wetlands.

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    Thermodynamic Effects on Particle Movement: Wind Tunnel Simulation Results
    NIU Qinghe, QU Jianjun, ZHANG Kecun, LIU Xianwan
    2012 (2):  178-187. 
    摘要 ( 795 )   PDF(528KB) ( 1173 )  

    Sand/dust storms are some of the main hazards in arid and semi-arid zones. These storms also influence global environmental changes. By field observations, empirical statistics, and numerical simulations, pioneer researchers on these natural events have concluded the existence of a positive relationship between thermodynamic effects and sand/dust storms. Thermodynamic effects induce an unsteady stratified atmosphere to influence the process of these storms. However, studies on the relationship of thermodynamic effects with particles (i.e., sand and dust) are limited. In this article, wind tunnel with heating was used to simulate the quantitative relationship between thermodynamic effects and particle movement on different surfaces. Compared with the cold state, the threshold wind velocity of particles is found to be significantly decrease under the hot state. The largest decrease percentage exceedes 9% on fine and coarse sand surfaces. The wind velocity also has a three-power function in the sand transport rate under the hot state with increased sand transport. Thermodynamic effects are stronger on loose surfaces and fine particles, but weaker on compacted surfaces and coarse particles. 

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    Effects of Normalized Difference Vegetation Index and Related wavebands′ Characteristics on Detecting Spatial Heterogeneity
    Using Variogram-based Analysis
    WEN Zhaofei, ZHANG Ce, ZHANG Shuqing, et al
    2012 (2):  188-195. 
    摘要 ( 935 )   PDF(1069KB) ( 1191 )  

    Spatial heterogeneity is widely used in diverse applications, such as recognizing ecological process, guiding ecological restoration, managing land use, etc. Many researches have focused on the inherent scale multiplicity of spatial heterogeneity by using various environmental variables. How these variables affect their corresponding spatial he- terogeneities, however, have received little attention. In this paper, we examined the effects of characteristics of normalized difference vegetation index (NDVI) and its related bands variable images, namely red and near infrared (NIR), on their corresponding spatial heterogeneity detection based on variogram models. In a coastal wetland region, two groups of study sites with distinct fractal vegetation cover were tested and analyzed. The results show that: 1) in high fractal vegetation cover (H-FVC) area, NDVI and NIR variables display a similar ability in detecting the spatial he-  terogeneity caused by vegetation growing status structure; 2) in low fractal vegetation cover (L-FVC) area, the NIR and red variables outperform NDVI in the survey of soil spatial heterogeneity; and 3) generally, NIR variable is ubiquitously applicable for vegetation spatial heterogeneity investigation in different fractal vegetation covers. Moreover, as variable selection for remote sensing applications should fully take the characteristics of variables and the study object into account, the proposed variogram analysis method can make the variable selection objectively and scientifically, especially in studies related to spatial heterogeneity using remotely sensed data.

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    Major Function Oriented Zone: New Method of Spatial Regulation for Reshaping Regional Development Pattern in China
    FAN Jie, SUN Wei, ZHOU Kan, CHEN Dong
    2012 (2):  196-209. 
    摘要 ( 1470 )   PDF(909KB) ( 1406 )  

    Newest planning methods implemented by Chinese government are promoting a coordinated regional development and shaping an orderly spatial structure by applying the regulation of territorial function. This article analyzes the problems of spatial planning and regional strategy caused by the wrongly-set primary goal of economic development; it states that the three-fold objective of competitiveness, sustainability, and welfare fairness shall be the principal for China to implement the spatial regulation in the new era; it discusses about theoretical thoughts and technology framework of conducting the ′Major Function Oriented Zone′ based on their different major functions that each region plays in urbanization and industrialization, ecological constructions, grain productions, and protection of natural and cultural heritages; it introduces the new concept of ′Major Function Oriented Zone′ that include the major functions category, the stereo regional equilibrium mode, the two-level zoning specification, and the territorial development intensity; it offers a zoning scheme that defines development-optimized and development-prioritized zones as regions with massive urbanization and industrialization, development-restricted zones as ecological constructing or grain producing regions, development-prohibited zones as natural and cultural heritage protecting regions; and finally it addresses the main obstacle for implementing ′Major Function Oriented Zone′, which is the institutional arrangement of the supreme goal of high GDP growth rate that is currently being implemented.

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    Spatio-temporal Patterns of Intra-urban Land Use Change in Beijing, China Between 1984 and 2008
    KUANG Wenhui
    2012 (2):  210-220. 
    摘要 ( 1482 )   PDF(1114KB) ( 1344 )  

    Urban internal structure is essential information for urban geography researchers and urban planners or managers. This research aims to examine the spatial structure changes of internal urban land use based on the interpreted datasets of 1984 and 2008. Spatio-temporal patterns of internal land use conversion and urban expansion are analyzed, and then dominant driving factors (e.g., social economy, population growth and urban planning) were identified. The results indicate that Beijing′s intra-urban layout has experienced tremendous adjustment from compact to disperse configure, otherwise its function objects have shifted from the major economic and industrial development before the 1990s to the combination with cultural, high-technological and inhabitable city at present. The dominant urban land use transformations include the relocation of industrial lands from core districts to suburban or other provinces, and the accelerating expansion of residential areas and green spaces for supplying the demand of housing and ecological protection. Although Beijing′s urban planning has experienced three major adjustments and improvement since the 1980s, its optimization of urban internal patterns still remains a challenge.

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    Relationship Between Social Economic Agglomeration and Labor Productivity of Core Cities in Northeast China
    ZHANG Peng, YANG Qingshan, ZHAO Yichun
    2012 (2):  221-231. 
    摘要 ( 1331 )   PDF(639KB) ( 1426 )  

    Dalian, Shenyang, Changchun and Harbin are the four core cities which play an essential role in terms of promoting the economic development in Northeast China. In this paper, the impact of urban agglomeration on labor productivity is explored by making comparisons among these four cities. The model used for analysis is a classical model derived from previous studies. Some indicators, such as population density and economic density, were selected to examine the impact of urban agglomeration on the labor productivity based on the time-series data for the four cities from 1990 to 2007. The four main conclusions are: 1) The promotion from the growth rate of population density on the growth rate of labor productivity is limited. 2) The negative relationship exists between the growth rate of employment density and the growth rate of labor productivity. 3) Agglomeration effect exists in the four cities, the highest one is Dalian, Shenyang takes the second place, followed by Changchun and Harbin, and the predominant promotion exerted on the labor productivity is the output density.

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    Agricultural Land Use Optimal Allocation System in Developing Area: Application to Yili Watershed, Xinjiang Region
    ZHANG Ying, ZHANG Hongqi, NI Dongying, SONG Wei
    2012 (2):  232-244. 
    摘要 ( 722 )   PDF(1357KB) ( 1165 )  

    In developing countries, land productivity involves little market, where the agricultural land use is mainly determined by the food demands as well as the land suitability. The land use pattern will not ensure everywhere enough land for certain cropping if spatial allocation just according to land use suitability. To solve this problem, a subzone and a pre-allocation for each land use are added in spatial allocation module, and land use suitability and area optimization module are incorporated to constitute a whole agricultural land use optimal allocation (ALUOA) system. The system is developed on the platform .Net 2005 using ArcGIS Engine (version 9.2) and C# language, and is tested and validated in Yili watershed of Xinjiang Region on the newly reclaimed area. In the case study, with the help of soil data obtained from 69 points sampled in the fieldwork in 2008, main river data supplied by the Department of Water Resources of Xinjiang Uygur Autonomous Region in China, and temperature data provided by Data Center for Resources and Environmental Sciences, Chinese Academy of Sciences, land use suitability on eight common crops are evaluated one by one using linear weighted summation method in the land use suitability model. The linear programming (LP) model in area optimization model succeeds to give out land area target of each crop under three scenarios. At last, the land use targets are allotted in space both with a six subzone file and without a subzone file. The results show that the land use maps with a subzone not only ensure every part has enough land for every crop, but also gives a more fragmental land use pattern, with about 87.99% and 135.92% more patches than the one without, while at the expense of loss between 15.30% and 19.53% in the overall suitability at the same time.

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    Rise and Fall of Recent Chinese Coastal Resort Development: Case of Beihai Silver Beach, Guangxi, China
    LIU Jun, BAO Jigang
    2012 (2):  245-254. 
    摘要 ( 700 )   PDF(717KB) ( 1362 )  

    Based upon a case study of Silver Beach coastal resort of Beihai, Guangxi Zhuang Autonomous Region, this article examines the rise and fall of Chinese coastal tourist resort development since the 1980s. It explores the causes for and responses to the decline of Chinese coastal resorts. The data were collected through in-depth interviews with twelve local key information providers, and secondary information sources such as government archives, survey reports, and resort plans. It was found that the rise and fall of Chinese coastal resorts in the last three decades is closely linked to the transitional reform from a central planned economy to a market economy. Three stages of coastal tourism development were identified in a sequence of rapid growth, decline and redevelopment. It was government financial funds and high local government involvement that promoted the rapid expansion of coastal resorts during the 1980s. However, coastal resort decline occurred when transitional reform was intensified and deflationary policy executed after 1992. Institutional failure is found to be the main reason of Chinese coastal resorts decline since the mid-1990s. The government-dominated pattern could not be sustained and should be restructured in forthcoming coastal tourism development in China. Revival strategies should emphasize enhancing market-oriented reform in the declining resorts on both supply and demand sides.

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