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  • YANG Guoliang, ZHANG Jie, AI Nanshan, LIU Bo
    Acta Geographica Sinica. 2006, 61(12): 1281-1289. https://doi.org/10.11821/xb200612005
    Baidu(72)

    The Zipf theory is the law to study the relation between word frequency and word sequence which is now extensively used in city size structure, city spatial fractal, economics, sociology, and so on. From supposition to discussion, this paper proves that tourist flow size grading structure is in conformity with the Zipf theory in aid of the Zipf and difference degree index. The scaling section feature and internal structural difference in each scaling range of domestic and inbound tourist flow size grading structure in Sichuan province were studied in this paper based on statistic data of domestic tourist flow from 1996 to 2004. The result shows that tourist flow size grading structure has possessed the Zipf feature, even could be sectioned by fractal dimension scaling in certain years, and the bifurcation points of each scaling range can be determined by regression equations. The scaling section may be divided into two types, which are effective and ineffective scaling sections. Viewing from the tourism development in Sichuan province, the space distribution area of tourist flow ineffective scaling section is reducing and effective scaling section area is increasing. The Zipf index can be used to divide the scope of each scaling section and analyze the internal structural feature of effective scaling section and the changing law of the tourist flow size grading structure. For the region without the unobvious Zipf feature, equilibrium degree and difference index can be used to study the difference of the internal structure. The study shows that the results of effective scaling section being analyzed by the Zipf index and ineffective scaling section by equilibrium degree and difference index accord with the objective reality, also clearly reflect the structure scaling section feature, the internal structural difference of each section and the changing law of the total structure system. This is very important to enrich the methods of analyzing tourist flow size grading structure. Concerning the tourist flow size structure in Sichuan province, the Zipf index "q" of domestic tourist flow is mostly between one and two before 2002, and the size grading structure system assumes Pareto distribution pattern; after 2003, the Zipf index "q" further reduces and the tourist flow size structure is turning to logarithmic regular distribution pattern.

  • WANG Zhiwei, ZHAI Panmao
    Acta Geographica Sinica. 2003, 58(7s): 61-68. https://doi.org/10.11821/xb20037s007
    Baidu(212)

    Based on China's monthly precipitation data of 629 stations during 1950-2000, we calculated Z indices and separated them into seven Dryness and Wetness grades. Furthermore, a drought area index was proposed to study changes of drought extent. The results revealed that the different grades of droughts all show expanding trends in northern China's main agricultural area. Moreover, the area coverage of droughts in different seasons and different regions displayed different trends.

  • LIU Hailong, BAO Anming, CHEN Xi, ZHANG Xiaolei, ZHANG Jinying
    Acta Geographica Sinica. 2008, 63(4): 428-436. https://doi.org/10.11821/xb200804007
    Baidu(50)

    Development of transport, as one of the most important causes of changing economic activity and location advantages, is essential to economy development. The purpose of this paper, is to analyze the effect of transport accessibility on regional economy. Cobb-Douglas production function modeling, spatial analysis and network analysis in ArcGIS have been used to analyze this connection. Cobb-Douglas production function (Y = A Ka Lb, Y = Income, K=Capital, L=Labor, A=Technology, a and b are positive parameters) is used to reflect mutual relation between investment and output. It has been applied to many fields such as industry, energy sources, regional economic programming and agricultural management. Accessibility is a basic index which is used to describe traffic cost. Accessibility is one of the main reasons to cause spatial difference of regional economy, because it can reflect the degree of convenience from one place to another using certain traffic system and the economic activity and location advantages at one place on a large scale. Macroeconomic development can be seen as output of social capital investment. As part of social capital investment, infrastructure construction is very important to the regional economic development. In order to analyze the effect of transport accessibility on investment performance in regional economy and its weight in the economic growth, the authors adopted Cobb-Douglas production function and its regression modeling to constructe a homeostasis equation based on the relationship between investment (transport accessibility and total investment) and output (GDP). The timescale includes 11 years from 1995 to 2005 which was divided into two stages (1995-2000, and 2000-2005, especially). Also, we integrated spatial analysis method in GIS with economic modeling theory and constructed a multifactor regression equation. According to these models, feasibility of developing transport accessibility and its roles in macroeconomy have been analyzed with the spatial-temporal change of transport network and change characteristic of macroeconomy in the same term. The result indicates that the transport accessibilities are still very low and disproportional in many places in Xinjiang. Transport accessibilities polarize in some regions. There are big gaps among the other regions. Also, it has not come into being an organic pattern in line or polygon besides some points. It also shows that economic development depends mainly on investment scale when transport accessibility is suitable for some economic level, however, investment performance would be restricted by transport accessibility when the latter is lower than the level. There exists different response relationships between fluctuation of transport accessibility and economy in different terms. The improvement of transport accessibility will be in the interests of national economy. Transport cost, one of the most important factors, differs greatly throughout Xinjiang. It is very high in most areas. The spatial distribution of difference is consistent with that of economy based on the analysis of transport cost in increasing 10,000 yuan GDP increase per capita. According to the result, we found Cobb-Douglas production function and the regression modeling can link transport accessibility with macroeconomy. A quantitative analysis has been made between the change of transport network in space and the regional economic performance with the models. The final result shows this method is valuable to decide and optimize investment scale. This study can provide basis for steady, harmonious and balanced economic development.

  • LI Jian, NING Yuemin, WANG Mingfeng
    Acta Geographica Sinica. 2008, 63(4): 437-448. https://doi.org/10.11821/xb200804008
    Baidu(23)

    The development of globalization and advancement of production technology further lead to the transformation of social production organization. New international division of labor has penetrated into the inner layer of products, and the global value chain and the global production networks have been brought into multidisciplinary research. The new theories can better explain the new changes of production organization in modern world. Based on introducing the concepts and remarks of global production networks, this paper firstly discusses the general organization of global production networks of computer industry. Secondly, according to two indexes of value increment and profitability, the paper proposes two kinds of smiling curve and takes the GPN framework to explain it, including value analysis and its spatial competition, corporation organization and power distribution. Thirdly, the paper studies the smiling curve of Chinese computer industry, and holds discussions on value and its spatial competition, and then discusses embeddness of Chinese computer industry to global production networks.

  • WANG Ji, JIANG Zhihong, SONG Jie, DING Yuguo
    Acta Geographica Sinica. 2008, 63(3): 227-236. https://doi.org/10.11821/xb200803001
    Baidu(50)

    Based on the same term observations of extreme temperature data during 1961-2000 in China, we have evaluated seven model's output product including frost days (FD), growing season length (GSL), extreme temperature range (ETR), warm nights (TN90), and heat wave duration index (HDWI) supplied by the IPCC-AR4. The results show that all the models have the capability of modeling temperature characteristics in spatial and temporal variations and there are systematic errors in each model. This result indicates that the models' simulation accuracies for the five temperature indices are in the order from the best to the worst: FD, TN90, HWDI, ETR and GSL. In terms of the spatial distribution, the bad modeling effect is TN90, the characteristic distributions of other extreme temperature indices can be modeled. Generally, GFDL-CM2.0 and MIROC3.2 (hires) can best model the extreme temperature indices in China.

  • Ailikun, GUO Weidong
    Acta Geographica Sinica. 2003, 58(7s): 108-116. https://doi.org/10.11821/xb20037s013
    Baidu(9)

    In this research, a new type of desertification index is built by using the anomalies of differences between the air temperature (Ta) and the 0cm soil temperature (Ts) over northern part (35oN north, 100oE east) of China. Depending on the data from 1956 to 2000, the most serious desertification happens over the eastern part of Northwest China (35o~45oN, 100o~110oE) in both spring and summer, which began from the 1970s, and became much remarkable from the 1980s. A tendency of desertification is also found over Northeast China (45o~52oN, 120o~135oE) from the 1990s. Although the precipitation over central North China (35o~45oN, 110o~120oE) decreased notably from 1956 to 2000, we have not found the tendency of desertification over this area. The desertification indices (Ta-Ts) over the above three areas are correlated to the precipitation very well, which indicates the key roles of precipitation to the desertification index. The high correlations between Ta-Ts and NDVI in summer of eastern part of Northwest China and both spring and summer of central North China show the feasibility of the desertification index used in this research.

  • SHI Jun, DING Yihui, CUI Linli
    Acta Geographica Sinica. 2008, 63(3): 237-246. https://doi.org/10.11821/xb200803002
    Baidu(77)

    Based on the daily highest temperature data covering the period 1961-2005, temporal and spatial characteristics and their changing in mean annual and monthly high temperature days (HTDs) and the mean daily highest temperature (MDHT) during annual and monthly HTDs in East China were studied. The results show that the mean annual HTDs were 15.1 and the MDHT during annual HTDs was 36.3 oC in the past 45 years. Both the mean annual HTDs and the MDHT during annual HTDs were negative anomaly in the 1980s and positive anomaly in the other periods of time, oscillating with a cycle of about 12-15 years. The mean annual HTDs were more in the southern part, but less in the northern part of East China. The MDHT during annual HTDs was higher in Zhejiang, Anhui and Jiangxi provinces in the central and western parts of East China. The high temperature process (HTP) was more in the southwestern part, but less in the northeastern part of East China. Both the numbers of HTDs and HTP were most in July, and the MDHT during monthly HTDs was also the highest in July. In the first 5 years of the 21st century, the mean annual HTDs and the MDHT during annual HTDs increased at most of the stations, both the mean monthly HTDs and the MDHT during monthly HTDs were positive anomaly from April to October, the number of each type of HTP generally was the most and the MDHT in each type of HTP was also the highest.

  • YUE Wenze, XU Jianhua
    Acta Geographica Sinica. 2008, 63(3): 247-256. https://doi.org/10.11821/xb200803003
    Baidu(32)

    The urban thermal environment effect resulted from urban heat island phenomena becomes prominent with the rapid urban expansion, which had adverse effect on the urban environment and the urban sustainable development. Spatial-temporal change of urban thermal environment is relevant to interactions of human activities such as the change of underlying surface, anthropogenic heat emission and environmental pollution. Due to the complexity of factors contributing to urban thermal environment, the routine observing methods and statistical methods are insufficient in acquiring data and analyzing the responses of human activities to thermal environment, especially discerning the major attributors from the others. Fortunately, the remote sensing and GIS can resolve the technical problem effectively, which can quantitatively explore the relationship of spatial-temporal change of thermal environment with human activities. Based on Landsat ETM+ images and taking the urban area inside the ring road of Shanghai as a case study, this paper employed Spatial Principal Component Analysis (PCA) method to analyze the spatial pattern and the influencing factors of urban thermal environment as a substitute of Multi-Criterion Evaluation (MCE) method. The results showed that urban construction density and population density, allocation of industries, types of underlying surface and diversity of urban landscape were the leading factors contributing to the urban thermal environment in the metropolitan area of Shanghai. The linear model including the four independent variables could reveal the response mechanism of human activities on thermal environment in Shanghai. From the model, urban building density and population aggregation were regarded as the most sensitive factors to thermal environment among these factors. Furthermore, the difference in spatial distributions of the main factors formation of the diverse urban thermal environment in different areas. The results would be of value to simulate spatial change of urban thermal environment and even put forward countermeasures to lessen the urban thermal environment intensity for policy makers.

  • Acta Geographica Sinica. 2013, 68(11): 1587-1588.
  • LI Xiaowen, , FANG Jingyun, PIAO Shilong
    Acta Geographica Sinica. 2003, 58(5): 659-667. https://doi.org/10.11821/xb200305003
    Baidu(90)

    Based on the multi-temporal remotely sensed data of TM, this research attempted to reveal the spatio-temporal trends in landuse and landcover in Lower Yangtze Region by depicting and analyzing the process and spatial heterogeneity of landuse & landcover changes in the region, especially placing emphasis on the transformation modes and spatial behavior of landuse. In order to achieve the goal, the magnitude and spatial distribution of landuse transformation from the 1988 to the 1998 were analyzed by the transformation matrixes and the spatial layouts of landuse, then changes of landuse degree and associated traits in spatial distribution were targeted by establishing and applying the landuse index. Furthermore, the spatial shifting of landuse transformation intensity was studied by conceiving and using Landuse Transformation Index. As a hot topic, the loss of cultivated land and its driving force were also included in this step, and the top ten significant forms of landuse transformation were analyzed, in particular the trends in spatial transformation according to their Important Value individually.

  • HU Xiaomeng, XU Honggen, CHEN Meijun, LI Yi, WANG Dutao, CHEN Min
    Acta Geographica Sinica. 2008, 63(3): 270-279. https://doi.org/10.11821/xb200803005

    The features and the development law of rhyolite landforms are unique. Based on the survey and analysis data, the paper has analyzed the types, the distribution and the development of the rhyolite landforms in Yandang Mt. The study results show that the landforms in this region can be divided into two types, six sub-types and sixteen type units. The peaks, cliffs and waterfalls are all distributed vertically at different heights, and the valleys and line-cliffs extend along the faults with strikes of NE, NW and EW horizontally. The development of the landforms in the region has experienced four stages in which there developed different kinds of landforms. The study in the paper can contribute to the building of this World Geopark and flourish the local tourism.

  • SUN Aizhi, FENG Zhaodong, TANG Lingyu,MA Yuzhen
    Acta Geographica Sinica. 2008, 63(3): 280-292. https://doi.org/10.11821/xb200803006
    Baidu(16)

    Sporo-pollen records from the western part of Chinese Loess Plateau revealed a detailed history of vegetation variation and associated climate changes since 13 ka BP. Before 12.1 ka BP, steppe or desert-steppe vegetation dominated landscape, which was then replaced by a coniferous forest under a generally wet climate (12.1-11.0 ka BP). The vegetation was degenerated into steppe landscape and further into a desert-steppe landscape from 11.0 to 9.8 ka BP. After a brief episode of a cool and wet climate (9.8-9.6 ka BP), a relatively mild and dry condition prevailed during the early Holocene (9.6-7.6 ka BP). The most favourable climate of warm and humid period occurred during mid-Holocene (7.6-4.0 ka BP) marked by forest-steppe landscape, and an alternation of steppe and desert-steppe has occurred since ~4.0 ka BP.

  • WU Shaohong, YANG Qinye, ZHENG Du
    Acta Geographica Sinica. 2003, 58(5): 686-694. https://doi.org/10.11821/xb200305006
    Baidu(49)

    Eco-geographical region is a major ecosystem in geographic zonality. A hierarchical system, which is formed by division or combination of natural features based on geographic relativity and comparison of major ecosystem factors and geographic zonality, is called eco-geographic regional system. A comparison of the studies of this topic between Chinese and overseas scientists will enrich ideology of this field, facilitate academic exchange with understandable scientific language and introduce China's progress to the world. The authors compared both China's and overseas eco-geographic regional systems in development process, hierarchical units, delineating criteria, mapping procedures and regions. The results indicate that there are main common points in the subject, such as objectives, research contents and service objects connecting with environment, ecology and global change. Of the existing eco-regional systems, Robert G Bailey's systems of the United States, North America and the continent are comparatively close to China's system in hierarchical units, mapping procedure and regions.

  • Acta Geographica Sinica. 2013, 68(12): 1736-1736.
  • MAO Longjiang, MO Duowen, JIANG Leping, JIA Yaofeng,LI Minglin, ZHOU Kunshu, SHI Chenxi
    Acta Geographica Sinica. 2008, 63(3): 293-300. https://doi.org/10.11821/xb200803007

    According to field investigations and sampling as well as laboratory analysis of magnetic susceptibility, grain size, optically stimulated luminescence (OSL) and AMS 14C dating of archaeological site profile of Shangshan in Pujiang area, Zhejiang, this paper revealed the process of environmental change since Mid-Pleistocene and discussed the background of Shangshan cultural development. The results show there were fluvial gravel sediments in Shangshan area in the earlier period of Mid-Pleistocene. But at about 173 ka BP of the late period of Mid-Pleistocene, uplift happened in Shangshan area because of the impact of the climate, sea level change and neotectonic action, movement, thus forming the second terrace of the river. Between 173-75 ka BP, the terrace received aeolian sediment, a layer of reticulate laterite about 80-100 cm thick deposited, and developed under a relatively high temperature. A layer of  Xiashu Loess about 1.0-1.5 m thick deposited on Shangshan terrace in late glacial, containing 80% of the loessal dust. At the beginning of the Holocene (11500 a BP-), temperature went higher gradually with more precipitation, the pre-historic human moved on the Shangshan terrace (11400-8600 a BP), which may connect the paleolithic culture and Neolithic culture. The lower place to the west of the Shangshan Site has been the two cycles process of the fluvial facies, lake and moor facies, indicating that the water source of the Shangshan pre-history is the river water or lake water. Moreover, two AMS 14C ages indicated the water resource disappeared more than 1000 years at most.

  • QIAN Jinxia, LI Na, HAN Pu
    Acta Geographica Sinica. 2014, 69(5): 672-680. https://doi.org/10.11821/dlxb201405010
    Baidu(14)
    Based on the daily mean temperature data of 70 meteorological stations in Shanxi Province from 1970 to 2012, the negative accumulated temperature in winter, average monthly temperature in January and extreme minimum temperature were computed and their changing trends were analyzed in this paper using linear trend estimation method, and their abrupt change points were observed by means of accumulated variance method and contours of the negative accumulated temperature in winter, average monthly temperature in January and extreme minimum temperature were compared respectively after being divided into two groups according to the abrupt change points. The results showed that the negative accumulated temperature in winter showed a remarkable decrease, and the average monthly temperature in January and extreme minimum temperature did not increase significantly. Changes were found between the two groups, the negative accumulated temperature decreased by 103.4℃, and the average monthly temperature in January and extreme minimum temperature rose by 0.7℃and 0.9℃, respectively. The negative accumulated temperature and extreme minimum temperature played a key role, which are the thresholds that the winter wheat Province could be planted or not. Under climatic warming, the winter wheat cultivable area and the reliable planting area expanded by 2.9×106 hm2 (increased by 52%) and 2.3×106 hm2 (rose by 79%), respectively.
  • MAO Jiangxing, YAN Xiaopei, LI Zhigang, ZHOU Suhong
    Acta Geographica Sinica. 2008, 63(3): 311-320. https://doi.org/10.11821/xb200803009
    Baidu(13)
    Research on the implementation effect of urban planning has developed from qualitative study to quantitative study. In this way, this paper uses GIS technology, both quantitatively and qualitatively, along with related official materials as well as survey data, to understand the impact of urban planning upon land use of Shenzhen city. Accordingly, marked impacts of planning upon land use have been identified. After the 1980s, for instance, though the speed of the practical population increase is far beyond that estimated in urban plans, land use increase is effectively managed according to the plans of both 1982 and 1996. (1) Urban planning has effectively controlled and guided urban spatial structure of the city. Under the backdrop of high speed urbanization, urban structure has successfully kept an optimized structure. (2) Urban planning has successfully controlled the expansion of land use of the inner city, the so-called special economic development zone (SEDZ). The expansion of the new construction proceeds according to the planning. Nevertheless, the control of land use of the outer city is by no means success. The construction of the size besides the SEDZ has been largely out of control. Urban planning fails to adjust and control the sprawl of land use there. (3) Urban planning management also has significant impact upon the adjustment as well as control of land use. Specifically, the impacts of the authorization of the Construction Land Planning Permission Certificate is prominent, which results in massive engrossment of agricultural land, greens, trees, and waters, and therefore brings about massive change of land use across districts. In addition, a division between the inner city and the outer city is identified in terms of urban planning management. On the one hand, the control of land use within the SEDZ is very successful; on the other hand, however, land use out of the SEDZ is largely ineffective.
  • GUO Qiyun, CAI Jingning, SHAO Xuemei, SHA Wanying
    Acta Geographica Sinica. 2003, 58(4): 569-576. https://doi.org/10.11821/xb200304011
    Baidu(295)

    Interdecadal variabilities of East-Asian summer monsoon are studied according to the sum of sea level pressure gradient which is ≤-5 hPa between the land (110oE) and sea (160oE) from 10oN to 50oN. The sum for each year from 1951 to 2000 is divided by the mean sum averaged for the total 50 years, to form a series of Summer Monsoon Index (SMI). It shows a systematic reduction during the period of 1951-2000. Strong monsoon (SMI ≥1.0) was predominated during the first half of the studied period. SMI was less than 1.0 since 1976. Association of the climate in China to the SMI is examined based on the calculation of correlation coefficients between monthly mean temperatures and precipitations in each of 160 stations covered the whole land area of Chinese territory. It indicates that summer (June to August) precipitation increased in North China and decreased along the lower reaches of the Changjiang River when summer monsoon was stronger than the normal, and vice versa. Summer temperatures were higher along the Huaihe and Changjiang rivers when summer monsoon was stronger than the normal.

  • LI Cuizhen, KONG Xiangbin, SUN Xianhai
    Acta Geographica Sinica. 2008, 63(3): 321-329. https://doi.org/10.11821/xb200803010
    Baidu(117)

    The paper quantifies cultivated land resources economic value, social insurance value and ecological service value in Beijing from 1990 to 2005. The results indicate that: (1) The economic value per hectare increased rapidly from 12.57×104 yuan in 1990 to 108.12× 104 yuan in 2005. (2) In Beijing region, the social insurance value supplied by cultivated land resources is low, but the demand for the social insurance value of the rural residents is high. The supply is 49.19 ×104 yuan/hm2 in 1997 and 74.82 ×104 yuan/hm2 in 2005, while the demand is 160.56 ×104 yuan/hm2 in 1990 and 305.48 ×104 yuan/hm2 in 2005. As the most important basic resources for rural population, cultivated land resources have been overexploited, thus the rural social insurance system should be established as soon as possible, shifting land insurance function out. (3) The total ecological service value went up at first, then decreased greatly, being 142.75 ×108 yuan in 1990, 171.21 ×108 yuan in 1994 and 70.87 ×108 yuan in 2005, respectively, which is due to the decrease of cultivated land resources in Beijing region. But the total ecological service value demand and diversification demand increased because of population growth and living standard raising. In order to keep and improve the vegetation cover, the government should make some ecological compensation for the rural residents. Finally, the paper puts forward that in order to preserve cultivated land resources, the interests of every value subject need to be taken into account, especially the farmers' interest, and that the three values of cultivated land resources would be coordinated.

  • ZHANG Fugang, LIU Yansui
    Acta Geographica Sinica. 2008, 63(2): 115-122. https://doi.org/10.11821/xb200802001
    Baidu(103)

    The agriculture, rural and farmer development are the principal and radical problems in the recent economic and social process in China. Nowadays, aiming at building a moderately prosperous society in all respects and modernizing the country, the project of new socialist countryside construction was advanced at the Fifth Plenary Session of the 16th Central Committee of the Party, which means advanced production, improved livelihood, a civilized social atmosphere, clean and tidy villages and efficient management. Though many researches have been conducted on the new socialist countryside construction and given some suggestions, there have been relatively few studies on the research of rural development theory. It is an original approach to the analysis of the elements and configuration of the whole rural development system to provide theoretical basis for choosing rural development models based on the view of system theory. The results are as the follows: (1) The regional system is a urban-rural integration, so it is very necessary to study rural development problem in the general framework of the whole regional system. (2) Regional rural development system is a complicated synthesis, including regional rural development core system and regional rural development exterior system. The former is composed of rural natural system, rural economic system, rural social system and rural ecological system, and the latter consists of regional development policies, international trade circumstance, etc. The essence of rural development is the process of mutual coupling and coordination of the two sub-systems. (3) The regional rural comprehensive ability lies on two aspects including the rural development inner ability and the exterior drive of urbanization and industrialization. The interaction mechanism obeys parallelogram principle in physics. The evolvement characteristics of rural development system are different in the different combinations of the inner and exterior driving forces. (4) According to the difference of rural development driving forces, rural development models are classified into two types, namely the dominant type of rural self-development and the dominant type of the exterior drive of industrialization and urbanization, and six sub-types at the second level, which are industry driving, villages and towns construction driving, labor force transfer driving, characteristic industry driving, eco-tourism development and specialized market organization driving. In conclusion, it is a scientific approach to the exploration of regional rural sustainable development models, based on the analysis of elements, construction, and function of regional rural development system and characteristics.

  • GUO Zhaohui,XIAO Xiyuan,CHEN Tongbin,LIAO Xiaoyong,SONG Jie,WU Bin
    Acta Geographica Sinica. 2008, 63(1): 3-11. https://doi.org/10.11821/xb200801001
    Baidu(110)

    A total of 219 of agricultural soil and 48 of vegetable samples were collected from the midstream and downstream, Hengyang to Changsha, of Xiangjiang River of Hunan Province. The spatial distribution, accumulation characteristics and potential risk of heavy metals in the agricultural soils and vegetables were depicted in details by three different approaches, including total contents of 7 metal elements in soils and vegetables, GIS map of heavy metals in soils, and multi-analysis of the relationship between metals content of soils and egetables in this study. The results show that there are higher accumulations of heavy metals such as As, Cd, Cu, Ni, Pb and Zn in agricultural soils, and the contents of Cd (2.44 mg kg-1), Pb (65.00 mg kg-1) and Zn (144.13 mg kg-1) are 7.97, 3.69 and 1.63 times of background contents of the corresponding heavy metals in soils of Hunan Province, respectively. There are about 13.2% of As, 68.5% of Cd, 2.7% of Cu, 2.7% of Ni, 8.7% of Pb and 15.1% of Zn in all the collected soil samples from the investigated sites which have overran the contents for heavy metal of China Environmental Quality Standard for Soils (GB15618-1995, Grade II). The pollution characteristics of multi-metals in soils are mainly reflected by Cd. Contents of As, Cd, Cu, Pb and Zn in vegetable soils are significantly higher than those in paddy soils, respectively. The ratios of vegetable samples which As, Cd, Ni and Pb concentrations are higher than the Maximum Levels of Contaminants in Foods (GB2762-2005) are 95.8%, 68.8%, 10.4% and 95.8%, respectively. There are significantly positive correlations between the concentrations of Cd, Pb and Zn in vegetables and the content of them in vegetable soils (P < 0.01). It is very necessary to focus on potential risk of heavy metals for food safety and human's health in agricultural soils and vegetables in the midstream and downstream of Xiangjiang River, Hunan Province of China.

  • WU Shidai, WANG Qiang
    Acta Geographica Sinica. 2008, 63(2): 123-134. https://doi.org/10.11821/xb200802002
    Baidu(106)

    The coastal areas of southeastern China are the main force engine of China's economic growth. With its fast development, remarkable economic disparities occurred and along with the deepening of the reform and opening up policy in recent years, the economic disparities presented an expanding tendency. Based on 55 cities in the coastal areas of southeastern China during the period 1995-2005, this paper carried out a preliminary exploration of the changes in overall and partial spatial differences and the spatial pattern evolution, characteristics and causes. First, 1995-2005, the difference in the coastal areas of southeastern China at the level of economic development and the trend of the "polarization" are consistent, which proved that there exists a "polarization" phenomenon in southeastern coastal areas. Second, 1995-2003, the regional economic disparities in southeastern coastal areas continue to expand during this period. The economic disparities of the three major regions show a south-to-north gradual declining trend, indicating that such periodic changes in regional differences were mainly caused by the internal differences in Guangdong and Fujian. Since 2003, the economic differences in the southeastern coastal areas have been shrunk, and meanwhile the differences in the economic development of the three major regions also show a shrinking trend, which are the same as to the overall difference in the coastal areas of southeastern China , mainly due to the balanced development of the Yangtze River Delta region. Finally, the spatial evolution of the regional economy and regional economic differences are in the same line, corresponding to a "polarization → proliferation" phenomenon.

  • LIU Jianrong,SONG Xianfang,YUAN Guofu,SUN Xiaomin,LIU Xin,CHEN Feng,WANG Zhimin,WANG Shiqin
    Acta Geographica Sinica. 2008, 63(1): 12-22. https://doi.org/10.11821/xb200801002

    In order to reveal the characteristics and climatic controls on the stable isotope composition in precipitation over Northwest China, seven stations have been selected from the Chinese Network of Isotopes in Precipitation (CHNIP). During the year 2005, monthly precipitation samples have been collected and analyzed for the composition of δ18O . The established local meteoric water line "D = 7.05δ18O - 2.17, based on the 50 monthly samples obtained, could be treated as isotope input functions across the region. The deviations of the slope and the intercept from the Global Meteoric Water Line indicated the specific regional meteorological conditions over Northwest China. The monthly δ18O values were characterized by a strong correlation with the surface air temperature and a weak correlation with precipitation amount. However, if only the % values during summer period have been taken into account, the amount effect visualized. Spatial distributions of δ18O have properly portrayed the atmospheric circulation background in each month over Northwest China. The quantitative simulation of δ18O, which involved a Rayleigh fractionation model and a kinetic fractional model, demonstrated that the kinetic fractionation was the dominating function of condensation of raindrops. Furthermore, the raindrops suffered re-evaporation during the falling process, and the precipitation vapor has been mixed with a quantity of local recycled water vapor. A multiple linear regression equation and a δ18O-T relation were gained by using meteorological parameters to evaluate physical controls on the long-term values. The established δ18O-T relation, which has been based on the present-day precipitation, was the first step of quantitatively reconstructing the paleo-climate.

  • Orginal Article
    Jing LI, Zixiang ZHOU
    Acta Geographica Sinica. 2014, 69(7): 933-944. https://doi.org/10.11821/dlxb201407006
    Baidu(11)

    As a typical experimental Soil and Water Conservation District, the Yanhe River basin has long been plagued by soil erosion due to severe human disturbances. The 'Grain-For-Green' project has been practiced to increase grain yield to feed the mass population in starvation and curbed the continually deteriorating ecological situation. It is importantly scientific to explore watershed landscape pattern and hydrological processes. Exerting remote sensing and geographic information technology, this paper firstly analyzed simulated ecological hydrological process in the Yanhe River basin based on SWAT model. On this basis, it applied landscape indices method, land use change on eco-hydrological processes was quantitatively described, particularly those soil erosion influences caused by the change of landscape pattern with the complicated topography and soil type status; then we defined the landscape unit including topography, soil and land use/land cover change (LUCC) information, constructed a comprehensive landscape indices which was closely related to soil erosion, and reflected the coupling relationship between regional landscape pattern change and soil erosion. The results are as follows: (1) this paper constituted the spatial heterogeneity of hydrological response units (HRUs) by several factors such as land use type, soil type, topography, etc. At the landscape level, seven landscape indices were selected with principal component factor analysis, which are DCAD, GYRATE_SD, COHESION, SHEI, TCA, PAFRAC, IJI, etc. Coupled analysis on relationships of landscape indices, annual runoff and annual sediment in each sub-basin, the correlation coefficient of seven selected landscape indices and runoff is very small and cannot pass all significant tests. But correlation among the indices except for TCA and IJI and sediment yield is significant; the absolute value of the correlation coefficient is between 0.3 and 0.5. (2) This paper built Slope-HRU landscape index: coupling relationship between Slope-HRU landscape indices and annual sediment in each sub-basin is very comprehensible, and correlation coefficient is -0.6, which is significantly negatively correlated. Based on 'source-sink' landscape theory of soil erosion, Slope-HRU landscape index was fabricated to reflect the relationship between landscape pattern and soil erosion process to a certain extent. According to the space distribution of R value of Slope-HRU landscape index in 41 sub-basins, the results showed that: in the sub-basin scale, Slope-HRU landscape indices and annual sediment have obvious regional differentiation regularity. And R value spatial variation of Slope-HRU landscape indices and the variation of annual sediment amount were on contrary. On the other hand, the R value increased from southeast to northwest, with annual sediment decreasing from southeast to northwest.

  • WANG Chengjin
    Acta Geographica Sinica. 2008, 63(2): 135-146. https://doi.org/10.11821/xb200802003
    Baidu(126)

    With the development of the third party logistics, logsitcs company as a professional economic form to organize logistics activities with the spatial network is well aware of the growing importance. Much attention is paid to the spatial network of logistics company. Based on discussion about research process of logistics company, this paper analyzes the theory about spatial network of logistics company and discusses its spatial system, function ties and operation mechanism. Logistics company is composed of corporation factors and logistics factors with different spatial attributions, moving regularity and organization characteristics whose united operation generates function differentiation and location separation among different members of logistics company, which develops into the spatial network including organizing network of corporation factor and operating network of logistics activities, namely the static phase and dynamic phase. Logistics company constructs its corporation factor network at urban and regional scales. Urban network includes the headoffice, operating department and distribution center with different corporation functions or logistics functions. The headoffice is located at urban centre, the distribution centre tends to be in the suburbs of a city, and the operating department is situated in the regions with many logistics activities. Regional network includes headquarter, regional headoffice, local branch, local office and operating department with different corporation functions or logistics functions. Corporation headquarter tends to be located in large cities, regional headoffice is generally at a political-economic centre in each logistics operating region, local branches are concentrated in capital city, economic centre and transport hub. Operating network of logistics activities comprises scheduled transport line, distribution system and logistics network. Transport line is the primary operating way of logistics activities which includes trunk and branch transport lines. Distribution system helps logistics company to transfer the cargoes throughout the country and improve its market competition with the development of regional distribution centre, urban regional distribution centre and urban distribution centre. The optimization, amalgamation and intertexture of scheduled transport line and logistics distribution system can develop into the primary operating mode of logistics network, namely hub-and-spoke system.

  • LI Xiaoyan, ZHANG Shuwen, WANG Zongming, ZHANG Huilin
    Acta Geographica Sinica. 2004, 59(6): 989-997. https://doi.org/10.11821/xb200406023

    Based on regionalized variable theory, semivariograms of geo-statistics were used to research the spatial variability of soil properties quantificationally. The results showed that the semivariograms of soil organic matter were best described by spherical model, the best model for semivariograms of soil N and available K were exponential model and that of available P belongs to linear with sill model. Those soil properties have different spatial correlations respectively, the range of organic matter is the highest and that of available P is the lowest, and the spatial correlation of N and available K belongs to moderate class. Their spatial heterogeneity degrees were different too. The degrees of organic matter and total N were the highest, the degree of available K was in the next place and that of available P was the lowest. Influenced by the shape, topography and soil of the study area, all isotropics of available P were obvious in all directions while anisotropics of others were manifested. According to the analytical results, supported by GIS, Kriging and IDW were applied to describe and analyze the spatial distribution of soil properties. The results indicated that soil organic matter, total N and available K were distributed regularly from northeast to southwest, while available P was distributed randomly and its structural characteristics were not so distinctive as those of others.

  • MA Jianhua
    Acta Geographica Sinica. 2004, 59(6): 998-1011. https://doi.org/10.11821/xb200406024
    Baidu(18)

    The vertical variations of soil compositions, properties, types according to genetic classification and taxonomic classification, and the north boundary of subtropical zone on the southern slope of Funiu Mountain were discussed in this paper based on soil survey in field and soil physical and chemical analysis in laboratory. There were some vertical varying laws of soil compositions and properties on the southern slope of Funiu Mountain. (1) The content of fulvic acid in soil humus exceeds that of humic acid in all profiles of soil (HA/FA<1). The ratios of HA/FA in surface horizons are rising from foot to top of the mountain. The degree of humification in soil humic acid at 900 m asl is the lowest. (2) Along the altitude from foot to top of the mountain, both soil pH and base saturation percentage go down first, then go up. (3) Soils below 900 m asl have remarkable clayification horizon, argic horizon appears in each soil profile, and soils above 900 m asl have no clayification and argic horizons. (4) All of soils have higher degree of weathering and ferrallitization, average migration coefficients (Kmx) of most oxides and the values of β in all of soil bodies are below 1, the values of "Saf" are smaller than 5.06, the contents of Fed in illuvial horizons are higher than 20 g·kg-1, the percentage of Fed/Fet in illuvial horizons is higher than 40%, and many kinds of ferromanganese (concretion and coating) appear in all soil bodies below 900 m asl. But for soils with lower degree of weathering, no ferrallitization takes place, and no ferromanganese appears in all soil bodies above 900 m asl. The north boundary of subtropical zone on south slope of Funiu Mountain is in the area between S3 and S4, ranging from 900 m to 1000 m, the average height of which is at 950 m above sea level.

  • WANG Lin, OUYANG Hua, ZHOU Caiping, ZHANG Feng, BAI Junhong, PENG Kui
    Acta Geographica Sinica. 2004, 59(6): 1012-1019. https://doi.org/10.11821/xb200406025
    Baidu(77)

    The distribution of soil organic matter (SOM) and nitrogen of Gongga Mountain were studied in this paper. The results showed that the contents of SOM and N of A horizon had an ascending trend with the increase of the elevation. The vegetation types distributed higher than the mixed broad-leaved conifer forest had the irregular trends. In the transitional communities such as mixed forest and treeline, the contents of SOM and N were higher than other vegetation types. The distribution of SOM and N of A horizon was determined by the mutual effect of climate and vegetation types. The vertical distribution of SOM and N in soil profile had the similar trends in all kinds of vegetation types, i.e., the content of A horizon was higher than that of the B and C horizons, which was the same to the distribution of dead animals and plants in soil. There were N accumulation peaks in A horizon of the transitional communities. The soil C:N is between 7 and 25, which is lower relative to the appropriate C:N of 25-30. The soil C:N increased with the increase of the elevation, but its vertical distribution in the soil profile varied with different vegetation types. The N in the SOM existed mainly in the form of organic nitrogen, and the soil C:N was significantly correlated with SOM.

  • CAO Youhui, LI Haijian, CHEN Wen
    Acta Geographica Sinica. 2004, 59(6): 1020-1027. https://doi.org/10.11821/xb200406026
    Baidu(75)

    In this paper, two mathematic models are used to measure the spatial structure and the competition pattern of the coastal container port system of China from 1992 to 2001. Shift-share analyses reveal some characteristics for the competition pattern of the coastal container port system of China: (1) Both between (inter) and within (intra) the different port ranges, the net volumes of the shift effects are very notable. (2) In competition, the Pearl River Delta container port ranges are all along superiorior; the around the Bohai Sea container port range is throughout inferior; the Changjiang River Delta container port range is relatively complicated. (3) From 1995 to 1998, Shanghai was one of the major winners interms of total shift, but in the other two periods, it lost some TEU. (4) Shenzhen and Ningbo ports have been the major winners interms of total shift since 1992.

  • DUAN Zengqiang, P. H. Verburg, ZHANG Fengrong, YU Zhenrong
    Acta Geographica Sinica. 2004, 59(6): 1037-1047. https://doi.org/10.11821/xb200406028
    Baidu(107)

    CLUE-s (Conversion of Land Use and its Effects in small extent) is a model for simulating spatial changes in land use. The model was applied for regional agriculture and forest land-use system simulations in many countries. The author extended the CLUE-s model with a dynamic neighborhood analysis. The extended model (CLUE-sII) could simulate the self-organizational processes, spontaneous processes and the competition processes of the land-use changes. CLUE-sII can also implement different simulation schemes according to the characteristics of the study area. The local factors and the neighborhood factors play different roles in each scheme. Therefore, the researchers could find the best scheme for the specific study area. Land use change from 1991 to 2001 is simulated using CLUE-sII for Haidian District, Beijing. The results indicate that neighborhood factor analyse is important to simulate urban land-use changes and the scheme that took the neighborhood factor as a magnifying factor to the spontaneous processes obtained the best results, with which the whole map correspondence proportion gained 77% and the Kappa of urban attained 0.754. The case study in this paper showed that CLUE-sII could simulate urban sprawl with multiple land-use types at a high spatial and temporal resolution. Through constructing multiple simulation schemes, one can not only find the best simulation performance, but also could obtain more information on the importance of different land-use drivers.