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  • Research Articles
    GONG Zhaoning, LI Hong, ZHAO Wenji, GONG Huili
    . 2013, 23(4): 753-768. doi: 10.1007/s11442-013-1042-6
    CSCD(6) Crossref(1)

    The reservoir wetland, which is the largest artificial wetland in Beijing, constitutes one of the important urban ecological infrastructures. Considering two elements of natural environment and socio-economy, this paper established the driving factor indexing system of Beijing reservoir wetland evolution. Natural environment driving factors include precipitation, temperature, entry water and groundwater depth; social economic driving factors include resident population, urbanization rate and per capita GDP. Using multi-temporal Landsat TM images from 1984 to 2010 in Beijing, the spatial extent and the distribution of Beijing reservoir wetlands were extracted, and the change of the wetland area about the three decade years were analyzed. Logistic regression model was used to explore for each of the three periods: from 1984 to 1998, from 1998 to 2004 and from 2004 to 2010. The results showed that the leading driving factors and their influences on reservoir wetland evolution were different for each period. During 1984-1998, two natural environment indices: average annual precipitation and entry water index were the major factors driving the increase in wetland area with the contribution rate of Logistic regression being 5.78 and 3.50, respectively, and caused the wetland growth from total area of 104.93 km2 to 219.96 km2. From 1998 to 2004, as the impact of human activities intensified the main driving factors were the number of residents, groundwater depth and urbanization rate with the contribution rate of Logistic regression 9.41, 9.18, and 7.77, respectively, and caused the wetland shrinkage rapidly from the total area of 219.96 km2 to 95.71 km2. During 2004-2010, reservoir wetland evolution was impacted by both natural and socio-economic factors, and the dominant driving factors were urbanization rate and precipitation with the contribution rate of 6.62 and 4.22, respectively, and caused the wetland total area growth slightly to 109.73 km2.

  • Special Research on Sanjiangyuan
    YAN Huimin, YAO Zhijun, HUANG Heqing, JIANG Dong, DONG Xiaohui, DUAN Rui, ZHANG Yili
    . 2013, 23(5): 860-870. doi: 10.1007/s11442-013-1049-z
    CSCD(2) Crossref(3)

    As they are products of glacier movement, the water body composition and water quality attributes of glacial lakes have distinct characteristics compared with inland lakes. Although satellite remote sensing provides an effective approach to monitor water quality, lack of in-situ measurement data on the status and environment surrounding glacial lakes presents a major constraint in relating satellite data to water quality indicators. This study presents findings of a preliminary investigation into water quality attributes of 3 glacial lakes in the Mount Qomolangma region. Suspended particulate matter (SPM), light absorption attributes of phytoplankton, nonalgal particles (NAP), and colored dissolved organic matter (CDOM) were measured. The suspended substance concentration varies markedly from 0-320 mg/L. This is considered to reflect differing stages of lake development. The chlorophyll concentration is much lower than that found for inland lakes, as landscapes that surround these high altitude lakes have almost no vegetation growth. The phytoplankton and CDOM concentration depend on long-term stability of lake slopes. Given the lack of exogenous and endogenous inputs in the Qomolangma region, CDOM in glacial lakes is significantly lower than in inland lakes. These preliminary findings could support efforts to appraise estimates of water quality parameters using remotely sensed images.

  • Special Research on Sanjiangyuan
    PAN Baozhu, WANG Zhaoyin, LI Zhiwei, YU Guo-an, XU Mengzhen, ZHAO Na, Gary BRIERLEY
    . 2013, 23(5): 871-882. doi: 10.1007/s11442-013-1050-6
    CSCD(11) Crossref(9)

    This study presents findings of the first systematic analysis of aquatic biotic assemblages in the source region of the Yellow and Yangtze Rivers. It provides an initial basis with which to select representative organisms as indicators to assess the aquatic ecological status of rivers in this region. Macroinvertebrates are considered to be good indicators of long-term environmental changes due to their restricted range and persistence over time. Field investigations of macroinvertebrates were conducted in August 2009 in the source region of the Yellow River, and in July 2010 in the source region of the Yangtze River. Altogether 68 taxa of macroinvertebrates belonging to 29 families and 59 genera were identified. Among them were 8 annelids, 5 mollusks, 54 arthropods and 1 other animal. In the source region of the Yellow River, taxa number, density and biomass of macroinvertebrates were 50, 329 individuals m-2 and 0.3966 g dry weight m-2, respectively. Equivalent figures for the source region of the Yangtze River were 29, 59 individuals m-2 and 0.0307 g dry weight m-2. The lower benthic animal resources in the source region of the Yangtze River are ascribed to higher altitude, higher sediment concentration and wetland degradation. Preliminary findings of this exploratory study indicate that hydroelectric power stations had a weak impact on benthic dwellers but wetland degradation caused by a series of human activities had a catastrophic impact on survival of macroinvertebrates. Ecological protection measures such as conservative grazing and vegetation management are required to minimize grassland degradation and desertification, and reduce soil erosion rate and river sediment discharge.

  • Research Articles
    ZHUO Ga, LA Ba, PUBU Ciren, LUO Bu
    . 2014, 24(1): 113-128. doi: 10.1007/s11442-014-1076-4
    CSCD(3) Crossref(5)

    The estimation of surface evapotranspiration (ET) with satellite dataset is one of the main subjects in the understanding of climate change, disaster monitoring and the circulation of water vapor and energy in Tibet Autonomous Region (TAR). This research selects satellite images on January 11, April 6, July 31 and October 19 in 2010 as the representative of winter, spring, summer and autumn respectively, estimates the distribution of daily surface ET based on the surface energy balance system (SEBS) along with potential evapotranspiration (PET) and ET derived from Penman-Monteith (P-M) method. The results are obtained as follows. (1) The seasonal distribution of ET and PET basically decreases from the southeast part to the northwest part of TAR. Although ET and PET have similar spatial distributions, there are still some differences to estimate the extreme values especially the maximum value in the middle and southeastern parts of TAR. No matter what kind of methods we adopted, the maximum value of ET and PET always appears in summer, followed by autumn or spring while that in winter is the smallest. (2) In order to better understand the accuracy of SEBS model in the estimation of ET, we compared the ET from SEBS and the ET obtained from P-M method. Results show that the ET from SEBS could estimates the variation trend of actual ET, but it slightly underestimates or overestimates the value of ET as a whole, especially for those areas with thick forest. (3) The spatial distribution of Normalized Difference Vegetation Index (NDVI) exhibits a decreasing trend from the southeast part to the northwest part of TAR which displays remarkable consistency of distributions between ET and vegetation index. ET is well positively related to NDVI, minimum, mean, maximum air temperature and sunshine duration in different seasons while negatively related to precipitation, relative humidity and wind speed in summer.

  • Research Articles
    LI Kaifeng, ZHU Cheng, JIANG Fengqing, LI Bing, WANG Xinhao, CAO Bo, ZHAO Xiaofan
    . 2014, 24(3): 526-538. doi: 10.1007/s11442-014-1104-4
    CSCD(5) Crossref(6)

    This study presents an analysis of the spatial-temporal distribution of 230 archaeological sites in Guizhou Province, Southwest China for three selected time periods from the Paleolithic Age to the Shang-Zhou Dynasties. The relationship between archaeological sites distribution and environmental changes is also discussed based on paleo-environmental proxies of δ18O and δ13C recorded in stalagmites from Southwest China. The results show that: in the Paleolithic Age (260-10 ka BP), archaeological sites were concentrated in the central, northwestern and southwestern parts of Guizhou, where the high-altitudinal karst landforms with many natural caves suitable for human habitation are developed. In the Neolithic Age (10-3.6 ka BP), most of human settlements were concentrated in the central, northwestern and southwestern parts, while, a fewer sites were found on river terraces in the southern and eastern parts, and the intermontane basins in the central and western Guizhou. During the Shang-Zhou Dynasties (3.6-2.2 ka BP), the sites were mainly distributed in the intermontane basins and on river terraces, which were suitable for primitive aerial farming. The analysis of paleo-environmental proxies of δ18O and δ13C since 260 ka BP suggested that climate fluctuations had little impact on human settlements in this study area. The distinct physical environment, especially the spatial patterns of karst landforms and arable land played an important role in the archaeological sites distribution of Guizhou.

  • Chuanglin FANG, Chenghu ZHOU, Chaolin GU, Liding CHEN, Shuangcheng LI
    地理学报(英文版). 2017, 27(12): 1431-1449. doi: 10.1007/s11442-017-1445-x
    CSCD(29)

    Mega-urban agglomerations are strategic core areas for national economic development and the main regions of new urbanization. They also have important roles in shifting the global economic center of gravity to China. However, the development of mega-urban agglomerations has triggered the interactive coercion between resources and the eco-environment. The interactive coupled effects between urbanization and the eco-environment in mega-urban agglomerations represent frontier and high-priority research topics in the field of Earth system science over the next decade. In this paper, we carried out systematic theoretical analysis of the interactive coupling mechanisms and coercing effects between urbanization and the eco-environment in mega-urban agglomerations. In detail, we analyzed the nonlinear-coupled relationships and the coupling characteristics between natural and human elements in mega-urban agglomerations. We also investigated the interactive coercion intensities between internal and external elements, and the mechanisms and patterns of local couplings and telecouplings in mega-urban agglomeration systems, which are affected by key internal and external control elements. In addition, we proposed the interactive coupling theory on urbanization and the eco-environment in mega-urban agglomerations. Furthermore, we established a spatiotemporal dynamic coupling model with multi-element, multi-scale, multi-scenario, multi-module and multi-agent integrations, which can be used to develop an intelligent decision support system for sustainable development of mega-urban agglomerations. In general, our research may provide theoretical guidance and method support to solve problems related to mega-urban agglomerations and maintain their sustainable development.

  • Chao BAO, Xiaojie CHEN
    地理学报(英文版). 2017, 27(12): 1450-1462. doi: 10.1007/s11442-017-1446-9
    CSCD(2)

    Due to the limitation of total amount of water resources, it is necessary to enhance water consumption efficiency to meet the increasing water demand of urbanizing China. Based on the panel data of 31 provinces in China in 1997-2013, we analyze the influencing factors of water consumption efficiency by spatial econometric models. Results show that, 1) Due to the notable spatial autocorrelation characteristics of water consumption efficiency among different provinces in China, general panel data regression model which previous studies often used may be improper to reveal its influencing factors. However, spatial Durbin model may best estimate their relationship. 2) Water consumption efficiency of a certain province may be influenced not only by its socio-economic and eco-environmental indicators, but also by water consumption efficiency in its neighboring provinces. Moreover, it may be influenced by the neighboring provinces’ socio-economic and eco-environmental indicators. 3) For the macro average case of the 31 provinces in China, if water consumption efficiency in neighboring provinces increased 1%, water consumption efficiency of the local province would increase 0.34%. 4) Among the ten specific indicators we selected, per capita GDP and urbanization level of itself and its neighboring provinces have the most prominent positive effects on water consumption efficiency, and the indirect effects of neighboring provinces are much larger. Therefore, the spatial spillover effects of the economic development level and urbanization level are the primary influencing factors for improving China’s water consumption efficiency. 5) Policy implications indicate that, to improve water consumption efficiency, each province should properly consider potential influences caused by its neighboring provinces, especially needs to enhance the economic cooperation and urbanization interaction with neighboring provinces.

  • Tao SONG, Yi CHENG, Weidong LIU, Hui LIU
    地理学报(英文版). 2017, 27(12): 1463-1480. doi: 10.1007/s11442-017-1447-8
    CSCD(13)

    Border areas are both important territorial security barriers and portals to the outside world. Considering the complicated geopolitical environment of China’s inland borders, analysis of the current status and mechanisms of influence of geo-economy in border areas is of great significance. Namely, this analysis is important towards leveraging traditional advantages to accelerate China’s development in border and minority areas. Based on a comprehensive analysis, our study constructed a framework to analyze the geo-economy in border areas, and also introduced three indexes: local economy, export-oriented economy and local development. In addition, our study systematically described geo-economic evolution in the border areas of China. We also analyzed the mechanism of geo-economic spatial differentiation in these border areas by using geographical detectors. Our results indicated that the level of geo-economic influence in border areas has grown steadily with significant spatial differentiation. The absolute geo-economic dominance of Northeast China gradually declines over time. Areas with geo-economic advantages are highly dispersed, showing a spatial polarization pattern with several polar nuclei including Mudanjiang city (Northeast China), Baotou city (Inner Mongolia), Bortala Mongol Autonomous Prefecture (Xinjiang), Dehong Dai and Jingpo Autonomous Prefecture and the city of Chongzuo (Yunnan-Guangxi area). Geo-economics in border area is mainly influenced by national policies, the development level of neighboring countries, as well as the desire of these countries to cooperate with China in bilateral trade. Favorable policies, traffic, cultural proximity and other factors also impact the geo-economics of border areas significantly. The Inner Mongolia and Tibet areas are mainly influenced by neighboring countries, while Northeast China and Xinjiang are mainly affected by Chinese policies; the Yunnan-Guangxi area is influenced by a combination of these factors. At the end of the study, we provide our recommendations for developing policies that further geo-economic advantages in complex geopolitical environments and in areas with varied development.

  • Xiaoyun LI, Yu YANG, Yi LIU, Hui LIU
    地理学报(英文版). 2017, 27(12): 1481-1498. doi: 10.1007/s11442-017-1448-7

    Frequent extreme weather events like drought, etc. in the context of climate change present huge challenges to agricultural production. To find out if farmers have taken measures against them and identify governments’ impact on their response measures are the foundation of and key to further improving relevant policies and farmers’ responsiveness. Taking the North China Plain as an example, the study analyzes farmers’ responses to frequent climate change-induced drought, and assesses the impacts of governments’ early- warning, policy support and other factors on farmers’ responses based on questionnaire survey data and an econometric approach. The results show that: (1) Farmers are responsive to drought, and they are more likely to take measures as the degree of drought deepening. (2) Governments’ regulation affects farmers’ responses, although only part of its regulation measures has remarkable effects. Governments’ early-warning messages can increase the possibility of farmers’ responding to drought, however, only when they get the early-warning in all the processes including before, during, and after disasters can the effects be significant. Currently, as the primary channel through which early-warning information is released, television cannot change farmers’ behaviors significantly. Early-warning is most effective when spread via two or more types of channels. In addition, governments’ (especially town and village level institutions’) policy support has certain impacts on farmers’ responses to drought, yet with less prominent effects in disaster years than in normal years; to provide subsidies, as a regulation measure, can encourage farmers’ initiative a lot in adopting response measures, but most of the farmers haven’t got support from any institutions. Both the structure and strength of government regulation need to be improved. (3) Farmers with different conditions respond differently. Farmer households in irrigation areas, those whose farmland is lower fragmented, and those with numerous agricultural family members tend to take response measures. The study can provide scientific reference to the making of relevant regulation policies under the background of acidifications.

  • Zhongxue ZHOU, Mengtao LI
    地理学报(英文版). 2017, 27(12): 1499-1520. doi: 10.1007/s11442-017-1449-6
    CSCD(11)

    The excessive expansion of urbanized areas has resulted in haphazard land utilization, immoderate consumption of superior agricultural land and water resources, significant fragmentation of agricultural landscape, and gradual deterioration of the agro-ecological environment. Combined, these factors cause poor land use efficiency. Under these circumstances, comprehensively assessing land use efficiency for urban agriculture is a key issue in land use research. Currently, evaluation methods for agricultural land use efficiency narrowly concentrate on aspects of economic input and output. However, urban agro-ecosystems can provide diverse economic, social, and ecological services and functions. In particular, the social and ecological services and functions originating from agricultural land, which have a higher value than economic services, play a significant role in ensuring regional social, ecological, and environmental security. However, recent research has rarely taken these benefits into consideration. Therefore, land use value has been greatly underestimated, which has resulted in mishandled and poor land use policies. In this study, we apply Landsat imagery and social and economic statistical data for the Xi’an metropolitan zone (XMZ) to investigate agricultural multi-functionality. We develop an evaluation framework for urban agricultural land use efficiency and identify agro-ecosystem services and functions as important outputs from agricultural land. The land use efficiency of urban agriculture is then evaluated using ecosystem services models, providing a mechanism for assessing spatial-temporal changes in land use efficiency in the XMZ from 1999 to 2015. Four important conclusions are reached from this analysis. First, the rapid urbanization and agricultural transformation from traditional cereal cultivation to modern urban agriculture has resulted in steadily increasing costs, outputs, and land use efficiency of urban agriculture. The total output value increased 41% and land use efficiency per hectare increased by 33.13% on average. Second, the spatial patterns of comprehensive output and land use efficiency were dominated by economic outputs from agricultural land. Areas near cities, which are dominated by orchard and arable land, provide more economic functions. These areas support and regulate services due to the transformation from extensive cereal production to intensive modern urban agriculture; therefore, they have higher output value and land use efficiency. In contrast, areas distant from cities, towns, and high traffic roads, namely, remote rural areas, provide more support and regulating services, but have relatively lower economic function due to inaccessibility to urban markets and slow agricultural transformation. Therefore, these areas have lower output value and land use efficiency. The spatial change in agricultural output and land use efficiency in urban areas is strongly dependent on the degree of urbanization and agricultural transformation. Third, the total output value and land use efficiency of urban agriculture measured with our approach are much higher than evaluations using traditional methods. However, the spatial patterns measured using the two approaches are in agreement. The evaluation framework integrates ecological services and economic and social functions into a comprehensive output from agricultural land. This approach is more methodical and accurate for evaluating the comprehensive efficiency of land use based on quantities and spatial scale because they are at the pixel scale. Finally, the evaluation results have important implications for enhancing current agricultural subsidies and even implementing ecological payment policies in China. Most importantly, they can be directly applied to agricultural transformation regulations, decision-making, and guidance for rational land utilization.

  • Lili JIANG, Qizhang LIANG, Qingwen QI, Yanjun YE, Xun LIANG
    地理学报(英文版). 2017, 27(12): 1521-1540. doi: 10.1007/s11442-017-1450-0
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    Ancient Chinese cartography dates back to the Western Jin Dynasty in the third century. Cartography was initiated during this period by Pei Xiu, a minister and cartographic expert, who suggested six principles of cartography. Pei Xiu, who is known as the father of Chinese cartography, oversaw the completion of the “Yu Gong Regional Maps”, along with 18 articles and the “Terrain Fangzhang Map” (AD 224-271). This led to a number of subsequent cartographic initiatives including the “Wooden Fangzhang Map” (an administrative map) which was completed by Xie Zhuang, a minister during the Southern Dynasties (AD 502-557), “Haineihuayi Tu” (Map of China and its neighbouring countries) (AD 730-805), drawn by Jia Dan, a cartographer of the Tang Dynasty, and “Shouling Tu” (an administrative map, AD 1031-1095), drawn by Shen Kuo, a scientist during the Northern Song Dynasty. Throughout the 16th century, ancient Chinese cartography developed continuously and cumulatively, and formed the specific characteristics of China ancient cartography. Although Western latitude-based and longitude-based mapping techniques introduced to China in AD 1460, the theories and methods of Chinese and Western mapping systems co-existed for over 400 years. The cultural heritage of Chinese cartography can be seen in many famous ancient Chinese maps, including astronomical figures and atlases (world, Chinese, regional, military, water conservancy, historical, and educational maps), charts, and maps of scenic spots. These have hitherto been kept in well-known archives and institutions across the world. They form an important part of the global cultural heritage of ancient maps and cartography. Given their high cultural value, these maps remain an important point of study. This paper provides a preliminary discussion on the rarity, application, and the historical, scientific, and artistic value of ancient Chinese maps.

  • Kai LIU, Maolin TANG, Rongzeng LIU, Yaochen QIN
    地理学报(英文版). 2017, 27(12): 1541-1555. doi: 10.1007/s11442-017-1451-z
    CSCD(1)

    Contemporary science philosophy suggests that discussing ontological problems is of fundamental significance broadly within certain specific disciplines. Natural and social science research are inseparable from philosophical guidance; for instance, the philosophy of geography is the ideological basis for geography. The traditional philosophy of geography is methodology- oriented, which primarily emphasizes the “logical structure of geography explanations,” and ignores the discussion of its ontology. This study, in the context of the philosophy of science, explores the relationships between methodology, ontology, and the philosophy of geography, defines the connotations of geographical ontology, analyzes the links and differences between philosophical ontology and scientific ontology of geography, clarifies the nature of geographical ontology, and summaries its theoretical values. The ontology of geography incorporates the philosophically ontological beliefs of geographers and geographical schools and the ontological commitment of the theory of geography. As different geographers hold different philosophical viewpoints, their ontological beliefs are different; one geographical theory asserts an ontological commitment of “what is there,” which determines the nature and types of objectives the theory references. The ontological beliefs of geographers determine their epistemology, methodology, and axiology, and the ontological commitment of a geographical theory is the premise and basis of that theory.

  • Mingxing CHEN, Hualou LONG, Chengjin WANG, Jinchuan HUANG, Fangqu NIU
    地理学报(英文版). 2017, 27(12): 1556-1576. doi: 10.1007/s11442-017-1452-y

    The “High-Level Forum of the Development of China’s Human Geography Under the Background of Change” was held in Beijing on January 22-23, 2016. More than 30 professors attended this forum. At this conference, they discussed the major progress made towards developing China’s human geography, as well as the existing problems, limiting factors, opportunities, international collaborations, emerging directions, and prospects in the development of this discipline. In recent years human geography has boomed, generating many important opportunities for its development. Establishing an academic community for joint research on major research issues and collaborative innovation is a promising and important route to take. We should embrace both domestic and international characteristics, to promote China’s human geography onto the world stage. Meanwhile, the cultivation of various scholarly talents is also of great value to enrich and advance the discipline.

  • Xinyue YE
    地理学报(英文版). 2017, 27(12): 1595-1596. doi: 10.1007/s11442-017-1454-9
  • Climate and Environmental Change
    SUN Rui, LIU Chang-ming, ZHU Qi-jiang
    Journal of Geographical Sciences. 2002, 12(1): 29-34.

    An exponential relationship between net primary productivity (NPP) and integrated NDVI has been found in this paper. Based on the relationship and using multi-temporal 8 km resolution NOAA AVHRR-NDVI data, the spatial distribution and dynamic change of NPP and fractional vegetation cover in the Yellow River Basin from 1982 to 1999 are analyzed. Finally, the effect of rainfall on NDVI is examined. Results show that mean NPP and fractional vegetation cover have an inclining trend for the whole basin, and rainfall in flood season influences vegetation cover most.

  • Climate and Environmental Change
    ZHANG Guo-ping, LIU Ji-yuan, ZHANG Zeng-xiang,ZHAO Xiao-li, ZHOU Quan-bin
    Journal of Geographical Sciences. 2002, 12(2): 153-162.

    Based on the results of remote sensing investigations of the landscapes of 1995 and 2000, the national distribution of sandy desertified land and its interaction with other landscapes are classified, and five zonal types are distinguished. The data of nationally distributed 400 meteorological stations of 1999 are processed. With the GIS method, the data are spatially interpolated, and the national database of wind field concerned with wind erosion is established. In arid and semi-arid areas of China, the intensity of wind field is one of the key factors that controls the development of landscape especially in desert and its adjacent area. Different indexes are set up to describe the intensity of wind field, the method suggested by the wind erosion prediction models of RWEQ is also adopted to express the intensity of wind. The Weibull distribution is used to describe the wind field in China. Based on the analysis of the process of the wind erosion-driven landscape changes, this article proposes and discusses the control measures of wind erosion.

  • Climate and Environmental Change
    YAN Denghua, DENG Wei, HE Yan
    Journal of Geographical Sciences. 2002, 12(3): 289-294.

    Based on the continuous monitoring data of hydrology and water quality in the period from 1972 to 1997, the responses of hydro-environment system to melt water in the Second Songhua River basin were derived. Because of melt water, the water quality in the Second Songhua River is good and changes very except that the contents of Hg and Mn in the water are higher. The contribution of melt water to the water fluxes in the Second Songhua River basin is distinct: the water flow in April increases remarkably, reaches the peak in the upper reaches. The pollutant contributions and water pollution indices (WPIs) of the Second Songhua River in April are high in the upper reaches while that in the lower reaches are low. The responses of hydro-environment system to melt water of that basin are affected by content of packed snow and the underlining surface systems.

  • Climate and Environmental Change
    ZHAO Mu-dan, TANG Guo-an, SHI Wen-zhong, LIU Yong-mei
    Journal of Geographical Sciences. 2002, 12(2): 171-176.

    The development and distribution pattern of rural settlements was greatly limited by their natural and social environment. Taking Yulin prefecture in northern Shaanxi’s Loess Plateau area as an example, 1:250,000 map-scale national geographical database as a major information source, a GIS-based research was conducted to investigate the spatial distribution of the rural settlements. In this paper, many significant characteristics of the rural settlement distribution are reviewed by means of a series of GIS-based information processing methodology. The results obtained in this study should be helpful for the urban and rural settlements reconstruction planning in this area.

  • Climate and Environmental Change
    ZHANG Yongqiang, SHEN Yanjun, YU Qiang, LIU Changming, A. Kondoh, TANG Changyuan, SUN Hongyong, JIA Jinsheng
    Journal of Geographical Sciences. 2002, 12(3): 295-300.

    Surface energy fluxes were measured using Bowen-Ratio Energy Balance technique (BREB) and eddy correlation system at Luancheng of Hebei Province, on the North China Plain from 1999 to 2001. Average diurnal variation of surface energy fluxes and CO2 flux for maize showed the inverse "U" type. The average peak fluxes did not appear at noon, but after noon. The average peak CO2 flux was about 1.65 mg m-2 s-1. Crop water use efficiency (WUE) increased quickly in the morning, stabilized after 10:00 and decreased quickly after 15:00 with no evident peak value. The ratio of latent heat flux (λE) to net solar radiation (Rn) was always higher than 70% during winter wheat and maize seasons. The seasonal average ratio of sensible heat flux (H) divided by Rn stayed at about 15% above the field surface; the seasonal average ratio of conductive heat flux (G) divided by Rn varied between 5% and 13%, and the average G/Rn from the wheat canopy was evidently higher than that from the maize canopy. The evaporative fraction (EF) is correlated to the Bowen ratio in a reverse function. EF for winter wheat increased quickly during that revival stage, after the stage, it gradually stabilized to 1.0, and fluctuated around 1.0. EF for maize also fluctuated around 1.0 before the later grain filling stage, and decreased after that stage.

  • Climate and Environmental Change
    A. Zaman, S.K. Choudhuri
    Journal of Geographical Sciences. 2002, 12(3): 301-304.

    A field experiment was conducted to study the effect of different crop sequences on water use, growth and yield of green gram (Vigna radiata (L) Wilezek) during 1992-93 and 1993-94 under rainfed upland condition in Indo-Gangetic plains of West Bengal. Green gram sown in the month of March as pre-rainy (summer) season crop, as and when the winter crops vacated the land, produced highest dry matter of 372 gm-2 which was significantly highest in black gram-yellow sarson sequence. The results of the field experimentation revealed that green gram gave highest grain yield to the extent of 10.80 q/ha when sown after black gram (rainy season) followed by yellow sarson (winter season) while the crop produced 10.63 q/ha under sesame-yellow sarson sequence. Highest water use of 267 mm was achieved in green gram under black gram-yellow sarson sequence and the crop gave water use efficiency of 4.07 kg ha-1mm-1 under black gram-yellow sarson sequences.

  • Climate and Environmental Change
    HE Fanneng, GE Quansheng, ZHENG Jingyun
    Journal of Geographical Sciences. 2002, 12(4): 427-434.

    According to the length of city perimeter and the administration systems recorded in the historical literatures of the Qing Dynasty, a set of methods is developed to convert the historical records into the area of urban land use, by which a set of preliminary estimated urban land use data of the 18 provinces during the Emperor Jiaqing (1820AD) in the Qing Dynasty, is achieved. Based on the above achievements, the regional differences of urban land use are analyzed, and the comparison in urban land use between the Qing Dynasty and present (1999) is made.

  • Climate and Environmental Change
    ZENG Pusheng
    Journal of Geographical Sciences. 2002, 12(3): 305-312.

    Based on field observations, the author proposes a new understanding on the formation of the first bend of the Yangtze River. The relationship between the formation of the first bend of the Yangtze River and Eocene magmatic activity is expounded, suggesting that the first bend of the Yangtze River is the result from choking of the strong magmatic activity in Eocene. As a result, the upstream became a natural reservoir, whose riverside between Mt. Yulong and Mt. Haba was burst, guiding Jinshajiang River running eastward. At the same time, the drastic uplift of the Qinghai-Tibet Plateau led to the deep dissection of the river cut down the channel, resulting in the formation of the Tiger Leaping Gorge. The magnitude of uplift in the study area (located in the eastern of the Tibetan Plateau) is calculated. Taking Mt. Yulong as a base, the magnitude of lift is 3,300 m from Eocene to Pliocene, adding 700 m since Pleistocene, totaling up to 4,000 m or so.

  • Climate and Environmental Change
    XU Feng,, GUO Suoyan, ZHANG Zengxiang
    Journal of Geographical Sciences. 2002, 12(4): 435-442.

    This paper discussed the spatial distribution of soil erosion in China at the end of the 20th century based on the second national soil erosion survey. The result indicated soil erosion is still the prime environmental problem in China. Soil erosion mainly occurs in the western regions of China, and the slight erosion type, ion the whole, exerts the greatest impact on soil erosion pattern. The distribution of water erosion shows the impact of landforms: slight water erosion mainly in mountainous and hilly areas, and half of violent water erosion on the loess landforms. Farmland, forestland and grassland are the major land use types of slight hydraulic erosion distribution, while the serious hydraulic erosion and slight wind erosion mainly occur on grassland. Thus, the conservation of the grassland is the key to either hydraulic and wind erosion control. The huangmian soil (a major type of cultivated soil developed from loess mother material) is the one facing the most serious threat from soil erosion in Chinas soil resources. Further discussion on the soil erosion distribution still needs more research on the method and relevant data analysis.

  • Climate and Environmental Change
    YUE Tian-xiang, YE Qing-hua, LIU Qing-sheng,GONG Zheng-hui
    Journal of Geographical Sciences. 2002, 12(2): 186-195.

    The models for landscape connectivity are distinguished into models for line connectivity, vertex connectivity, network connectivity and patch connectivity separately. Because the models for line connectivity, for vertex connectivity, and for network connectivity have long been studied and have become ripe, the model for patch connectivity is paid special attention in this paper. The patch connectivity is defined as the average movement efficiency (minimizing movement distance) of animal migrants or plant propagules in patches of a region under consideration. According to this definition, a model for landscape connectivity is mathematically deduced to apply to GIS data. The application of model for patch connectivity in the new-born wetland of the Yellow River Delta shows patch connectivity has a negative interrelation with human impact intensity and landscape diversity.

  • Climate and Environmental Change
    YAO Chun-xia, LI Bao-sheng, JIN He-ling, David Dian Zhang, YAN Man-cun, ZHU Yi-zhi, LI Hou-xin, ZHANGYu-hong,Luo Kai-li
    Journal of Geographical Sciences. 2002, 12(1): 65-71.

    The paper makes some analyses on 11 trace elements in the Milanggouwan stratigraphical section in the Salawusu River valley, which is regarded as a prototype geology-palaeoclimate record since 150 ka BP. The results show that the content and variation of trace elements has experienced remarkably regular changes in the pace with coarse and fine sedimentary cycles of palaeo-aeolian sands to its overlying fluvio-lacustrine facies or/and palaeosols. The trace elements with chemical properties of relatively active (V, Sr, Cu, Ni, As) and relatively stable (P, Pb, Rb, Mn, Nb, Zr) are a manifestation of the corresponding 27 changeable cycles between peak and valley values, appearing a multi-fluctuational process line of relative gathering and migration since then. The low numerical value distribution of these two types of trace elements in the aeolian sand facies represents erosion and accumulation under wind force during the cold-dry climate. Whereas their enrichments in both fluvio-lacustrine facies and palaeosols are related to the valley’s special low-lying physiognomic position between the Ordos Plateau and the Loess Plateau under the warm and humid climate conditions. The above relatively migrated and gathered change of the trace elements is the result of 27 climatic cycles of cold-dry and warm-humid, which is probably caused by repeated alternations of winter monsoon and summer monsoon in the Mu Us Sandy Land influenced by the climate vicissitudes in northern hemisphere during glacial and interglacial periods since 150 ka BP.

  • Climate and Environmental Change
    YIN Yong, ZHU Dakui, TANG Wenwu, Martini I. Peter
    Journal of Geographical Sciences. 2002, 12(3): 313-320.

    Sedimentary successions and internal structure of the coastal barrier-lagoon system of Boao, eastern Hainan Island were studied through utilizing data from test holes and trenches and ground-penetrating-radar (GPR) profiles. During late Pleistocene, fluvial and delta plains developed over an unevenly eroded bedrock during low sea level stand, followed by the formation of littoral and lagoon facies and defined coastal barrier-lagoon-estuary system during the post-glacial uppermost Pleistocene-lower Holocene eustatic rise of the sea level, and the upper Holocene high stand. GPR results show that Yudaitan, a sandy coastal bar backed by a low-laying land (shoal) just east of the active lagoon, is a continuous, parallel and slightly-wavy reflectors indicating homogeneous sandy or sandy gravel sediments, and inclined reflectors partly caused by progradation and accumulation of beach sand and gravel. Quasi-continuous, hummocky and chaotic reflectors from the shoal of Nangang village correspond to mixed accumulation of sands and clay. This research indicates the GPR is a non-intrusive, rapid, and economical method for high-resolution profiling of subsurface sediments in sandy gravelly coast.

  • Climate and Environmental Change
    LIANG Tao, ZHANG Xiumei, ZHANG Shen, YU Xingxiu, WANG Hao
    Journal of Geographical Sciences. 2002, 12(4): 443-450.

    Five typical land covers in West Tiaoxi catchment of China, including mulberry garden, bamboo forest, pinery, vegetable plot and paddy field, were studied on nitrogen loss in artificial rainstorm runoff and sediment. Triple duplication experiments have been carried out under the artificial rain condition with an intensity of 2 mm.min-1 and lasting 32 minutes in 3 m2 field. Export of various species of nitrogen in runoff and sediment were investigated. The results show that nitrogen loss amount and rate are quite different among five kinds of land covers. The loss of total nitrogen in runoff of mulberry is the largest and that of paddy field is the smallest. Particle nitrogen accounts for 70-90% of total nitrogen in runoff of various kinds of land covers. Loss of dissolved nitrogen in pinery is much higher than in other kinds of land covers, which are similar among them. More detailed species of dissolved nitrogen show their respective features among various land covers. Total amounts of nitrogen loss from the top 10 cm layer of 5 kinds of soils are estimated as high as 4.66-9.40 g.m-2, of which nitrogen loss through sediment of runoff accounts for more than 90%. The rate of total nitrogen losses are ranged in 2.68-14.48 mg.m-2.min-1 in runoff, which is much lower than that of 100.01-172.67 mg.m-2.min-1 in sediment of runoff.

  • Climate and Environmental Change
    WANG Sui-ji, NI Jin-ren
    Journal of Geographical Sciences. 2002, 12(1): 72-80.

    Straight river is generally regarded as one of the typical river patterns in conventional classifications in terms of their channel plain landforms. However, very few straight patterns were found to be distributed in wider spatial and temporal spans in the self-adjusted fluvial rivers. Thus, the questions occur such as that is it possible for a channel takes on a stable straight pattern? What are the main factors controlling the processes of the river pattern formation and transformation from a straight to other patterns? Various theories and hypotheses including geomorphic threshold hypothesis, the extreme hypothesis on energy dissipation rate, the stability theory, etc. have been developed to explain the aforementioned questions, but none of them is sound for the explanation to the straight-river formation. From the modern fluvial plain patterns, the straight patterns are not as stable as other typical patterns which occurred in nature; from the historic records of the river sedimentation, no apparent evidence was found to support the stable straight river evolution. Based on the analysis of existing theories, observations, evolvement processes of the channel patterns in the experimental results, this paper concluded that the straight pattern should not be included as one of the typical patterns that are self-formed and developed. This study is of importance to understanding of the river pattern formation and transformation.

  • Climate and Environmental Change
    ZHANG Zu-lu, LIU En-feng, NIE Xiao-hong, WANG Lin
    Journal of Geographical Sciences. 2002, 12(2): 196-201.

    The loess mounds are a newly discovered type of landforms on the Laizhou Bay plain south of the Bohai Sea. Research shows that they were formed in the late period of the late Pleistocene when the Bohai Sea was exposed in the period of late Wümu glacial age and changed into plain. As the exposed area is not protected by vegetation, the sediments at the sea bottom are blown and transported southward by strong north winds, and deposit on the coastal plains. As thick loess is accumulated, the loess mound landforms are formed in the direction of down wind.

  • Climate and Environmental Change
    ZHU Liping, LI Yuanfang, LI Bingyuan
    Journal of Geographical Sciences. 2002, 12(4): 451-459.

    The CC1 core, with a length of 216 cm, was drilled in the west part of the Chen Co (Lake) in southern Tibet Plateau. The 210Pb and 137Cs measurement indicated that it was a consecutive sedimentary sequence since ca. 1400 years. The ostracoda and their assemblages under the level of 1 cm samples' cutting interval were finished for this core to reveal the past environmental changes in the lake area. A total of 15 species of ostracods belonging to 7 genera in the core sediments had been identified. According to the ostracod distributions, abundances and preservations in the core, seven ostracod assemblages had been distinguished. The ostracod assemblages and their ecological features, together with the sediments dating decision were used to infer the past ca. 1400 years environmental changes of the Chen Co environmental evolutions in three stages, which had responded to the Medieval Ages Warm-period (MAW), the Little Ice Age (LIA) and modern warm period. The results show that the changes of the Chen Co environment had been mainly influenced by the climatic variations. The trend of the lake level fluctuations had been accorded with that of climatic variation during the past 1400 years.