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    2012年, 第22卷, 第5期 刊出日期:2012-10-05 上一期    下一期
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    论文
    Temporal Variations of Water Discharge and Sediment Load of Huanghe River, China
    LIU Feng, CHEN Shenliang, PENG Jun, CHEN Guangquan
    2012 (5):  507-521. 
    摘要 ( 1603 )   PDF(2649KB) ( 1868 )  

     Based on the data from gauging stations, the changes in water discharge and sediment load of the Huanghe (Yellow) River

    were analyzed by using the empirical mode decomposition (EMD) method. The results show that the periodic oscillation of water

    discharge and sediment load of the Huanghe River occurs at the interannual, decadal, and multi-decadal scales, caused by the periodic

    oscillations of precipitation, and El Niño/Southern Oscillation (ENSO) affects water discharge by influencing precipitation distribution and

    contributes to periodic varations in precipitation and water discharge at interannual timescale. The water discharge and sediment load of

    the Huanghe River have decreased since the 1960s under the influence of precipitation and huamn activities, and human activities

    attribute more than precipitation to the reduction in the water discharge and sediment load, furthermore, water abstraction and water-

    soil conservation practices are the main causes of the decrease in water discharge and sediment load, respectively. The reduction in

    sediment load has directly impacted on the lower reaches of the Huanghe River and the river delta, causing considerable erosion of the

    river channel in the lower reaches since the 1970s along with River Delta changing siltation into erosion around 2000.

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    Hydrological Impacts of Climate Change on Streamflow of Dongliao River Watershed in Jilin Province, China
    ZHANG Lei, LU Wenxi, YANG Qingchun, AN Yongkai, LI Di, GONG Lei
    2012 (5):  522-530. 
    摘要 ( 1075 )   PDF(682KB) ( 1525 )  

     The impacts of future climate change on streamflow of the Dongliao River Watershed located in Jilin Province, China have been

    evaluated quantitatively by using a general circulation model (HadCM3) coupled with the Soil and Water Assessment Tool (SWAT)

    hydrological model. The model was calibrated and validated against the historical monitored data from 2005 to 2009. The streamflow was

    estimated by downscaling HadCM3 outputs to the daily mean temperature and precipitation series, derived for three 30-year time slices,

    2020s, 2050s and 2080s. Results suggest that daily mean temperature increases with a changing rate of 0.435℃ per decade, and

    precipitation decreases with a changing rate of 0.761 mm per decade. Compared with other seasons, the precipitation in summer shows

    significant downward trend, while a significant upward trend in autumn. The annual streamflow demonstrates a general downward trend

    with a decreasing rate of 0.405 m3/s per decade. The streamflow shows significant downward and upward trends in summer and in

    autumn, respectively. The decreasing rate of streamflow in summer reaches 1.97 m3/s per decade, which contributes primarily to the

    decrease of streamflow. The results of this work would be of great benifit to the design of economic and social development planning in

    the study area.

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    Stable Isotopes in Precipitation in Xilin River Basin, Northern China and Their Implications
    WU Jinkui, DING Yongjian, YE Baisheng, YANG Qiyue, HOU Dianjiong, XUE Liyang
    2012 (5):  531-540. 
    摘要 ( 859 )   PDF(4535KB) ( 1219 )  

     Under the increasing pressure of water shortage and steppe degradation, information on the hydrological cycle in steppe region

    in Inner Mongolia, China is urgently needed. An intensive investigation of the temporal variations of δD and δ18O in precipitation was

    conducted in 2007–2008 in the Xilin River Basin, Inner Mongolia in the northern China. The δD and δ18O values for 54 precipitation

    samples range from +1.1‰ to –34.7‰ and –3.0‰ to –269‰, respectively. This wide range indicates that stable isotopes in

    precipitation are primarily controlled by different condensation mechanisms as a function of air temperature and varying sources of vapor.

    The relationship between δD and δ18O defined a well constrained line given by , which is nearly identical to the Meteoric Water Line in

    the northern China. The temperature effect is clearly displayed in this area. The results of backward trajectory of each precipitation day

    show that the vapor of the precipitation in cold season (October to March) mainly originates from the west while the moisture source is

    more complicated in warm season (April to September). A light precipitation amount effect existes at the precipitation event scale in this

    area. The vapor source of precipitation with higher d-excesses are mainly from the west wind or neighboring inland area and precipitation

    with lower d-excesses from a monsoon source from the southeastern China .

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    Carbon Storage and Vertical Distribution in Three Shrubland Communities in Gurbantünggüt Desert, Uygur Autonomous Region of Xinjiang, Northwest China
    GONG Yanming, HU Yukun, FANG Fei, et al.
    2012 (5):  541-549. 
    摘要 ( 979 )   PDF(735KB) ( 1013 )  

    This study was carried out in the Gurbantünggüt Desert, Uygur Autonomous Region of Xinjiang, Northwest China in August,

    2009. To quantify the storage, contribution and vertical distribution patterns of plant biomass carbon (PBC) and soil organic carbon (SOC)

    in the study area, we investigated the carbon concentrations and its vertical distribution in three different desert shrubland communities

    dominated by Reaumuria soongorica, Haloxylon ammodendron + R. soongorica and Tamarix ramosissima + R. soongorica, respectively. We

    analyzed vertical distribution of root biomass carbon and soil carbon contents by excavating soil profiles for each dominated community.

    The results show that SOC is considerably the larger carbon pool in the soil layers of 1.0–3.0 m (the mean value of three shrubland

    communities is 38.46%) and 3.0–5.0 m (the mean value is 40.24%). In contrast, 70.74% of belowground biomass carbon storage in 0–1.0

    m layer, and its content decrease with increasing soil depth. The Haloxylon ammodendron + R. soongorica shrubland community has the

    highest belowground biomass carbon among three selected communities. This study highlights the importance of SOC stored in deep soil

    layers (lower than 3.0 m from the surface) in arid shrubland communities in the global carbon balance. In addition, it provides the data

    support for revealing deep soil solid carbon potential, and offers scientific basis for the further research in the carbon cycle of terrestrial

    ecosystem.

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    Potential Role of Feldspathic Sandstone as a Natural Water Retaining Agent in Mu Us Sandy Land, Northwest China
    HAN Jichang, XIE Jiancang, ZHANG Yang
    2012 (5):  550-555. 
    摘要 ( 821 )   PDF(180KB) ( 1155 )  

    This paper analyzed the water-retention mechanism of feldspathic sandstone (fine- (< 1 mm diam.) and gravel-sized (2–3 cm

    diam.) in Mu Us Sandy Land, Northwest China. The objective of this study is to study the effect of feldspathic sandstone amendment on

    water retention in sandy land. The results showed that as the proportion of fine  feldspathic sandstone in the sandy land soil increased,

    the soil texture changed from sand to silt loam, the capillary porosity gradually increased from 26.3% to 44.9%, and the soil saturated

    hydraulic conductivity decreased from 7.10 mm/min to 0.07 mm/min. Feldspathic sandstone gravel formed micro-reservoirs in the sandy

    land soil, playing the role of a ′water absorbent′ and ′water retaining agent′ in sandy land. Amendment with feldspathic sandstone can

    increase water retention in the arable layer of sandy land by 67%. This study provides a theoretical basis for the amelioration of sandy

    land on a large scale. It can be concluded that amendment with feldspathic sandstone can improve the physical properties of sandy land

    soil and increase soil water retention.

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    Comparative Analysis of Influence Factors on Arable Land Use Intensity at Farm Household Level: A Case Study Comparing Suyu District of Suqian City and Taixing City, Jiangsu Province, China
    LU Xiao, HUANG Xianjin, ZHONG Taiyang, et al.
    2012 (5):  556-567. 
    摘要 ( 884 )   PDF(338KB) ( 1270 )  

    Using data from the farm household survey conducted in 2009, arable land use intensity (ALUI) and its influence factors at farm

    household level were investigated by the Tobit model. Suyu District of Suqian City and Taixing City of Jiansu Province, China were chosen

    as the regions for comparison. The results show that: 1) On the average, the ALUI, labor intensity, yield-increasing input, and labor-

    saving input are 15 238.14 yuan (RMB)/ha, 192 d/ha, 7233.01 yuan/ha, and 2451.32 yuan/ha in the less economically developed Suyu

    District, and 13 020.65 yuan/ha, 181 d/ha, 5871.82 yuan/ha, and 2625.97 yuan/ha in more economically developed Taixing City. The

    figures indicate that Suyu District has higher ALUI and labor intensity input but lower labor-saving input. 2) Comparing all the influence

    factors, the total arable land area in available and average plot size have bigger effects on arable land intensive use; to a small degree,

    family′s non-farm income affects labor intensity, yield-increasing input, and labor-saving input; the yield-increasing input decreases

    significantly when the householder has higher education attainment; the commercialization rates of agricultural products and the planting

    proportion of cash crops both have unstable influence on ALUI; the share of arable land rented in has few impacts on labor intensity,

    yield-increasing input, and labor-saving input.   3) There are no differences found in the internal impact mechanism of influence factors

    on the arable land intensive use behaviors of farm households. However, there are conspicuous disparities in the impact degrees and

    statistical significance based on varying economic levels. 4) Using the results as bases, this study proposes that the government should

    implement land management and agricultural policies according to local condition. And these policies should decrease land fragmentation

    to promote scale management of land and arable land use intensification.

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    Urban Expansion and Its Influencing Factors in Natural Wetland Distribution Area in Fuzhou City, China
    CAI Yuanbin, ZHANG Hao, PAN Wenbin, et al.
    2012 (5):  568-577. 
    摘要 ( 1243 )   PDF(5316KB) ( 2457 )  

    This paper principally focuses on land use dynamics, urban expansion and underlying driving forces in the Natural Wetland

    Distribution Area (NWDA) of Fuzhou City in the southeastern China. Based on time series Landsat TM/ETM+ imageries and historical data,

    relationships between urban land expansion and its influencing factors from 1989 to 2009 were analyzed by using an integrated approach

    of remote sensing (RS) and geographic information system (GIS) techniques. The results showed that built-up land increased from 151.16

    km2 in 1989 to 383.76 km2 in 2009. Approximately 64.25% of the newly emerging built-up land was converted from cropland (29.47%),

    forest and shrub (25.78%), water (3.73%), wetland (4.61%), and bare land (0.66%) during 1989 and 2009. With a remarkable decrease

    in cropland, the proportion of non-agricultural population increased by 23.6%. Moreover, rapid development of infrastructures, facilities,

    industrial parks, and urban and rural settlements along the Minjiang River resulted in the eastward and southward expansion of built-up

    land. Additionally, the growth pattern of built-up land in the NWDA is highly correlated with socio-economic factors, including the gross

    domestic product (GDP), GDP per capita, and structure of industry. As a result, the observed environmental degradation such as loss of

    cropland and wetland due to heavy pressure of rapid urbanization have greatly impaired the carrying capacity of city. Thus, in addition to

    scientific and rational policies towards minimizing the adverse effects of urbanization, coordination between the administrative agencies

    should be urgently strengthened to balance the conflicts between urban development and ecological conservation to make sure the

    sustainable land use.

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    Modeling Scenic Quality of Wetland Landscape Resources in South Dongting Lake, China
    WANG Baozhong, HE Ping, AN Shuqing, et al.
    2012 (5):  578-589. 
    摘要 ( 746 )   PDF(275KB) ( 1044 )  

    This study introduces a method to quantify the scenic value of wetland landscapes and provides the guidance on the allocation

    of efforts for the purpose of preserving the most important environments. Dongting Lake, a traditional tourist location, is one of the five

    largest freshwater lakes in China and a Grade 5A National Scenic Region. This study objectively analyzes the scenic resources of South

    Dongting Lake, and presents a model based on Quantification TheoryⅠto assess wetland scenic landscapes. Employing a multilinear

    regression relationship between landscape factors and their associated scenic value, we built up the Wetland Landscape Quantification

    Model (WLQM), which was used to classify 221 landscapes into five grades. Finally, some suggestions are proposed regarding quantitative

    assessment and its use for the sustainable development of wetland environments.

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    Spatial Effect of Mineral Resources Exploitation on Urbanization: A Case Study of Tarim River Basin, Xinjiang, China
    LI Xuemei, ZHANG Xiaolei, DU Hongru, CHU Shaolin
    2012 (5):  590-601. 
    摘要 ( 1033 )   PDF(7282KB) ( 1304 )  

    Mineral resources exploitation significantly affects the spatial structure and evolutive trend of urbanization in arid areas. In this

    study, the spatial autocorrelation method and the spatial computation model were used to investigate the spatial impacts of mineral

    resources excavation and processing on comprehensive level of urbanization in the Tarim River Basin, Xinjiang, China for the years of

    2000, 2006 and 2008. The results are as follows: 1) There was a spatial correlation of the development of mineral resources industry and

    the comprehensive level of urbanization in 2006 and 2008, with the spatial concentration trend rising significantly in 2006 and decreasing

    in 2008. 2) The patterns of local spatial concentration of mineral resources industry and of the comprehensive level of urbanization were

    relatively stable, and the two patterns showed signs of spatial correlationship. The higher was the degree of the concentration of mineral

    resources industry, the stronger was its impact on the spatial clustering of urbanization. 3) In 2000, mineral resources excavation and

    processing had a significant positive impact on the comprehensive level of urbanization in the region but not in its adjacent regions.

    However, in 2008, mineral resources excavation and processing significantly raised the comprehensive level of urbanization not only in the

    region but also in its neighboring regions. This research demonstrates that the development of mineral resources industry can strongly

    affect the trends and spatial patterns of urbanization.

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    Urban Hierarchy of Innovation Capability and Inter-city Linkages of Knowledge in Post-reform China
    LU Lachang, HUANG Ru
    2012 (5):  602-616. 
    摘要 ( 761 )   PDF(1507KB) ( 1767 )  

    The 2000s has witnessed increasing interests in cities′ role of innovation in the era of knowledge-based economy. Compared

    with substantial empirical analysis on the world city hierarchy of innovation, this paper attempts to examine the national urban hierarchy

    of innovation capability in China, in terms of ranking systems, spatial pattern and inter-city linkages of knowledge during the post-reform

    period since the late 1970s. Based on quantitative analysis such as principal component factor analysis and clustering analysis, this paper

    identifies the five-tier hierarchy of innovation, which is headed by Beijing and Shanghai, followed by the capital cities of each province

    and regional centre cities. The development of China′s urban hierarchy of innovation capability has been driven by such factors as the

    scale of innovation, scientific scale, innovation potential and innovation environment. The paper further investigates the inter-city

    linkages of knowledge measured by the number of co-authored papers among the cities. Beijing is positioned in the central position of the

    knowledge diffusion and knowledge cooperation innovation. More knowledge diffusion among high level cities has occurred than that

    among the low level cities as well as between the low level cities and high level cities, and provincial capital cities and the regional

    central cities.

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    Revisiting and Rethinking Regional Urbanization in Changjiang River Delta, China
    YANG Shangguang, Mark Yaolin WANG, WANG Chunlan
    2012 (5):  617-625. 
    摘要 ( 1930 )   PDF(440KB) ( 1324 )  

    China is entering a critical and accelerating phase of urbanization. As one of the most urbanized regions in China, the

    Changjiang (Yangtze) River Delta has experienced dramatic urbanization and urban transformation. However, in the recent years, many

    changes have taken place in this region and there is limited attention to the regional urbanization path evolution, its problems and the

    way to solve these problems. Therefore, we should revisit the urbanization process in the Changjiang River Delta again. In this paper, we

    revisited urbanization paths of the Changjiang River Delta by data analysis, influence factors of urbanization by the Gray Relational

    Analysis, and major challenges to urbanization of the Changjiang River Delta by theoretical considerations. We found that the urbanization

    of the Changjiang River Delta had experienced several stages of large-scale spatial and urban system restructuring. Within the Changjiang

    River Delta, Shanghai, Zhejiang and Jiangshu had experienced different urbanization path with local characteristics. But with their

    development model gradually converging, their urbanization model is also converging. We also found that the major influence factors

    affecting the Changjiang River Delta urbanization were dynamic change and urbanization was driven by different key factors in different

    socio-economic development stages. Meanwhile, the Changjiang River Delta urbanization is facing many problems such as existing

    institutional arrangements, including the hukou (household registration) system and others which can not meet the needs of current

    socio-economic development and urbanization. Therefore, it is imperative to promote institutional innovation and adopt a new

    urbanization development strategy for the sake of the orderly and sustainable urbanization development in the Changjiang River Delta.

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    Environmental Effects of Foreign Trade and Its Spatial Variations in Mid-eastern Provinces and Cities of China
    JIN Xianfeng, DONG Suocheng, LUO Lingjun, et al.
    2012 (5):  626-636. 
    摘要 ( 1014 )   PDF(5987KB) ( 1429 )  

    The studies on environmental effects of foreign trade and its spatial variations are helpful to design and implement

    environmental protection countermeasures. In order to eliminate the adverse effects of insufficient observation values on the accuracy of

    regression results and dynamic information quantity of fitting equation during empirical study, panel data of the mid-eastern provinces

    and cities of China from 1985 to 2007 were selected based on the adjustment of classical regression model in this paper. Panel unit root

    test and panel cointegration analysis method were applied to investigating the environmental effects of foreign trade and its spatial

    variations in the mid-eastern provinces and cities of China and its three groups divided by foreign trade dependence. The results show

    that all scale effects are positive, while all technical effects are negative and unable to counteract positive scale effects. Foreign trade

    development is regarded as an important cause for outstanding eco-environmental problems in the mid-eastern provinces and cities of

    China. Total effects and structural effects are significantly different among different groups because of spatial variations in environmental

    policies, export destinations, source of FDI, etc. Following the principle of ′coordinating generality and considering differences

    comprehensively′, it is essential to issue a series of policies and countermeasures corresponding to differences in regional environmental

    effect of foreign trade, in order to coordinate the relationship between foreign trade development and eco-environment in each region.

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