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  • Geo-information Science
    ZHANG Xue-yan, HU Yun-feng, ZHUANG Da-fang, QI Yong-qing
    GEOGRAPHICAL RESEARCH. 2009, 28(1): 10-19. https://doi.org/10.11821/yj2009010003
    CSCD(47)

    It is a key step to deepen the understandings about the structure, functions and processes of regional resources and environment by using spatial, quantitative, multi-scale and temporal analysis, and there are many obvious advantages to study on the spatial pattern, spatial difference and the related ecological & environment characteristics by using remote sensing technology. As an independent geographic and ecological unit, the status of Mongolia Plateau ecology system and its changes have great effects on the environment of North China and even the whole East Asia, which makes it necessary to develop certain research works in the whole Mongolia Plateau in both theory aspect and practice aspect. In this study, based on GIMMS NDVI dataset of 1982-2003, the new Mongolia Plateau NDVI Dataset using MVC method was constructed and the stability in the time scale was also assessed. Then three spatial statistic methods including Moran coefficient, semi variance function and fractal analysis, were selected to investigate the spatial pattern and spatial differentiation of NDVI in Mongolia Plateau. The results show that: (1) The NDVI in Mongolia Plateau shows positive spatial autocorrelation in the whole region and similar NDVI are apt to aggregate together, which means the vegetation cover of Mongolia Plateau is generally intact and little fragmental. The NDVI distribution pattern is indeed clear; (2) In spite of the effects of both structural factors and random factors, the spatial distribution pattern of NDVI in Mongolia Plateau is mainly controlled by the structural factors which induce 88.7% of the total spatial variations, while only 11.3% of the total spatial variations is induced by the random factors; (3) There exists a clear anisotropy about NDVI distribution pattern in Mongolia Plateau, and there are higher spatial autocorrelation in the Northwest-Southeast direction which means those points with similar NDVI value are mainly distributed along Northwest-Southeast direction. Generally, the radius of NDVI patch is about 1178km, and the length-width ratio of those patches is about 2.4. According to the research, temporal NDVI study based on spatial statistics method could not only explore the NDVI spatial pattern & spatial difference but also indicate the geographic essences of NDVI and the relevant spatial statistics parameters.

  • Environment and Ecology
    WANG Yun-cai
    GEOGRAPHICAL RESEARCH. 2009, 28(2): 284-292. https://doi.org/10.11821/yj2009020002
    CSCD(24)

    The city is the typical artificial landscape system with the characteristics of high fragmentation and low connectivity. Based on the connectivity theory of landscape ecological network, this article discusses the influence, connotation and the characteristics of landscape ecological connectivity and the connection to eco-city construction of China, analyses the typical graphical model of urban landscape ecological network, choosing γ=L/3(V-2),α=L-V+1/2V-5,β=2L/V (in the formula of γ, α and β, L is the number of factual line between knots, V is the number of knots), density of corridor d=L/A and indicator C= L/ξ nA (in formula of indicator d and C, L is the total length of corridor (km), A is area (km2), n is the number of knots, ξ is coefficient) as evaluation indicators and system and tries to evaluate the connectivity of Shanghai urban landscape ecological network in the road network, the green space network, the river system network and the road-river-green space compound network. The characteristics of river network are γ=0.65, α=0.45, β=3.85 and C =1.93. The characteristics of road network are γ=0.7,α=0.54,β=4.16 and C =2.08. The characteristics of green space network are γ=0.49,α=0.34,β=2.88 and C =1.44. The characteristics of road-river-green space compound network are γ=0.44,α=0.16,β=2.63 and C=4.13. Calculation analysis aims at providing a foundation for eco-city development construction and the urban landscape ecological network planning. Results show that, with different connectivity characters individually for each network, all the networks have higher connectivity, but the connectivity degrades sharply to the path-river-green space compound network. The indicators γ,α and β of road network degrade by 37%, 70% and 35% individually, and the indicatorsγ,α and β of river network degrade by 32%, 64% and 138% individually. All this shows fragmentation, isolation and low connection of Shanghai urban landscape eco-network. Finally, the paper gives some suggestions to dealing with the problems of promoting the circle connectivity, increasing the number and scale of network knots, and constructing the eco-bridge between three networks at each knot in order to promote connectivity of the total eco-network.

  • Earth Surface Processes
    LI Guo-sheng, WANG Hai-long
    GEOGRAPHICAL RESEARCH. 2009, 28(3): 571-582. https://doi.org/10.11821/yj2009030002
    CSCD(4)

    Five controlling experiments with a 3D diagnostic model including a wave-current coupled model, the third generation wave model SWAN (Simulating WAves Nearshore) and the bottom boundary layer model driven by the monthly discharge and sediment load of the Yellow River, was conducted to individually explore the effects of tidal currents, wind waves, residual circulation and the Bohai Sea circulation. The simulations on the temporal-spatial variation of SPM (Suspended Particular Matter) concentration and sediment flux from the Yellow River to the Bohai Sea were carried out. It could be discerned that the surface sediment concentration in the waters is quite low except for the Yellow River estuary. The sediment from the Yellow River cannot be delivered in long distance under the condition of tidal currents. Almost all the sediment from the Yellow River is deposited out of the river delta under the condition of the wind-driven residual circulation, and part of the inflow sediment is delivered to and deposited in the Bohai Gulf and the Laizhou Bay. The temporal variation of the suspended load concentration in vertical direction indicates that, the bottom shear stress induced by the wind-driven currents cannot reach the critical shear stress for erosion, and then no re-suspension is incurred. On the basis of wind forcing, the sediment from the Yellow River is mainly transported north-northwestward, and some sediment which is first delivered to the Laizhou Bay is continuously moved northward. On the basis of wind-driven and tide-induced residual circulation, the suspended load transport depicts an obvious 3D structure characteristic, and the depth-integrated sediment flux is quite different from the residual circulation in the Bohai Sea. The residual circulation cannot satisfy the transport structure of the suspended particle matters in the Bohai Sea, especially for the suspended load with complicated vertical processes. The phase of the temporal variation of the sediment concentration and transport pattern due to the interaction between waves and currents is consistent with that of the bottom shear stress, which is modulated by the wind variation, all of which is proved to have a ten-day cycle. Around the Yellow River estuary, currents fields contribute a lot to the outward transportation of the sediment. In other waters, the surface waves-induced bottom shear stress due to the wind forcing makes enormous sediment re-suspended locally, which continues to be transported by horizontal currents.

  • Geo-information Science
    YANG Cun-jian, BAI Zhong, JIA Yue-jiang, CHEN Xi, DENG Li-li
    GEOGRAPHICAL RESEARCH. 2009, 28(1): 19-26. https://doi.org/10.11821/yj2009010004
    CSCD(4)

    The relationship between the residential area extracted from multi-source remote sensing images and the population data at the three levels of city and prefecture, county and village in Sichuan province is discussed in this paper. This includes the following steps. Firstly, the rural and urban residential areas are extracted from Landsat TM images in Sichuan province, and the rural residential area and its building land are extracted from Quickbird Images in Juntun town, Xindu district, Chengdu City. Secondly, the residential areas for each unit of the three levels are obtained by overlaying and statistical analysis. Thirdly, the correlation relationship between the total residential areas and the total population, urban and town residential areas and the non-farm population, and the rural residential area and the farm population are analyzed respectively for city and county levels. The non-farm population strongly relates to the urban and town residential areas for city level with the correlation coefficient of 0.962 and county level with the correlation coefficient of 0.791.The non-farm population estimation models based on the urban and town residential areas are formulated respectively for the city and county levels by using regression analysis, whose judgment coefficients are respectively 0.926 and 0.625. Finally, the correlation relationship between the rural population, rural residential area and its building land are analyzed at the village level, and their correlation coefficients are respectively 0.806 and 0.825. The farm population estimation models based on the rural residential area and its building land are formulated by using regression analysis, whose judgment coefficients are respectively 0.65 and 0.68. It is shown that Landsat TM images are suitable for the estimation of the non-farm populations on a large scale, and Quickbird images are suitable for the estimation of the farm population on a small scale.

  • Environment and Ecology
    LI Pei-wu, LI Gui-cai, ZHANG Jin-hua, XU Feng, CHEN Li
    GEOGRAPHICAL RESEARCH. 2009, 28(2): 293-302. https://doi.org/10.11821/yj2009020003
    CSCD(22)

    This paper aims at exploring the urban ecological security level and assessment methods, and providing the scientific basis for the policy of the assessment and management on the urban ecological security. Shenzhen and four municipalities are taken as case studies to contrive an evaluating index system of urban ecological security depending on the Pressure-Status-Response (PSR) model. Firstly, the authors use four kinds of assessment models to simulate urban ecological security levels for those cities in 2006. A comparison is made between these models, based on the optimal method in combination of the subjective preference (Analytic Hierarchy Process) and the objective information (the modified Entropy), so as to identify the weights of all assessment indexes comprehensively. Then the ecological systems of Shenzhen and four municipalities are evaluated by applying the modified Grey Relational Analysis, the Matter-Element extension, the Fuzzy Comprehensive method and Main Constituents Projection method. The results are shown as follows: (1) Shenzhen's ecological security level is the highest, followed by Beijing, Tianjin and Shanghai, and Chongqing. Shenzhen, Beijing and Tianjin are labeled as relative safety at ecological security level, Shanghai is critically secure, and Chongqing is unsafe; Shanghai possesses the most developmental potentiality, while less in Shenzhen, Beijing and Tianjin, and still the lowest in Chongqing. From the conclusions above, the differences can be found in terms of ecological environmental pressures, the states of ecological systems and the responses of human beings for different cities. (2) In the studying method of urban ecological security evaluation, every model can obtain a similar result and can reflect the applicability on ecological security assessment. The results of Fuzzy Comprehensive method and Matter-Element Extension method are more comprehensive, and more differentiations can be revealed in Fuzzy Comprehensive method which can analyze the problems and offer the targeted measures than in the Matter-Element Extension. The conclusion of level judgment drawn by the Grey Associative Analysis is not possessed of comparability and cannot reflect the gaps among the cities. The Main Constituents Projection method cannot directly demonstrate the ecological security levels, although it can simplify the data structure, reduce the information loss of the original data and avoid the subjective arbitrariness as well as only showing the high or low level of ecological security. Thus there are some limitations in this method on ecological security assessment.

  • Earth Surface Processes
    FANG Hai-yan, CAI Qiang-guo, LI Qiu-yan
    GEOGRAPHICAL RESEARCH. 2009, 28(3): 583-591. https://doi.org/10.11821/yj2009030003
    CSCD(16)

    Slope surface is the most important sediment source area in basins on the Loess Plateau, and it is of great significance to the study on runoff generation capacity influenced by rainfall and slope surface characteristics. Seven runoff plots, located on the shady side of Tuanshangou Gully in hilly loess region on the Loess Plateau, were selected in this paper, using nine years of dataset, and the changing rule of runoff coefficients on different slope surfaces were studied in the context of different rainfall regimes. According to rainfall depth, rainfall duration, and rainfall intensity, the nine years of rainfalls in the study area were classified into three regimes through K-means clustering in SPSS software, i.e. rainfall regime A with high rainfall intensity, short duration and high occurring frequency, rainfall regime C with low rainfall intensity, long duration and low occurring frequency, and B the medium. Studies found that, for each of the study plots, runoff coefficients induced by rainfall regime A were the highest, and those induced by rainfall regime C the lowest. However, scale effect on runoff induced by rainfall regime A was the least, and that induced by rainfall regime C the largest. In slope Mao region, given the same slope degree, runoff coefficients firstly increased, and then decreased, and a peak value occurred for rainfall regime A on the slope surfaces of Nos.2-4 plots, however, runoff coefficients increased with increasing slope lengths for rainfall regimes B and C. For the slope surfaces of Nos.1, 4, and 5 plots that have the same slope length, under all the three rainfall regimes, runoff coefficients increased with increasing slope gradients. Entering gully slope area, runoff plot No.6 had the lowest coefficient in the condition of rainfall regime A and those induced with rainfall regimes B and C had higher values. For entire slope surface of No.7 plot, runoff coefficients induced by the three rainfall regimes had the medium values.

  • Climate and Global Change
    CHEN Xiao-qiu, PENG Jia-dong, LI Hui-min
    GEOGRAPHICAL RESEARCH. 2009, 28(1): 27-35. https://doi.org/10.11821/yj2009010005
    CSCD(22)

    Using monthly mean air temperature data from 101 meteorological stations during 1961-2003 in the entire Inner Mongolia and the method of Rotated Empirical Orthogonal Functions (REOF), we implemented a regionalization according to consistency in air temperature variations of the four seasons, and analyzed seasonal and regional differences of air temperature variations. The seasonal air temperature changes indicate an apparent east-west difference in Inner Mongolia. The air temperature fields of spring, autumn and winter could be divided into two regions, namely, the West Region and the East Region, whereas the air temperature field in summer could be classified into three regions, namely, the West Region, the Southeast Region and the Northeast Region. In terms of the interannual variation, the seasonal air temperatures in each region experienced an obvious transition from decrease to increase during the recent 43 years except the Southeast Region in summer, and the turning points appeared either in the middle and late 1980s (in the East Region of spring and summer, and in the East and West Regions in autumn and winter) or in the early and mid-1990s (in the West Region of spring and summer). Dealing with the linear trend, the slope and significance of increased temperature trends in the East Region are larger than in the West Region during spring and summer, whereas the slope and significance of increased temperature trends in the West Region are larger than in the East Region during autumn and winter. Generally speaking, the most significant temperature increase appeared in winter and summer and then in spring, and the slightest temperature increase was shown in autumn.

  • Environment and Ecology
    SU Zhi-fang, HU Ri-dong, LIN San-qiang
    GEOGRAPHICAL RESEARCH. 2009, 28(2): 303-310. https://doi.org/10.11821/yj2009020004
    CSCD(6)

    In the past 20 years, the Environmental Kuznets Curve has been regarded as one of the most powerful tools in studying the relationship between economic growth and environmental pollution. Among the conventional study in Environmental Kuznets Curve, most researchers implicitly assume that regional pollution is not affected by the neighboring regions. So, from analytical viewpoint and empirical behavior, the traditional methods used to examine the Environmental Kuznets Curve are suspected for neglecting spatial dependence among different regions. Consequently, the environmental policies based on the conclusions are hard to be convinced. With a view to the above shortcoming in describing the Environmental Kuznets Curve with the traditional methods, this paper investigates the relationship between environmental pollution and economic growth in China using panel data models which takes the spatial dependence into account. In this study, we select five types of pollution including waste water emission, waste gas emission, sulfur dioxide mission, dust emission and smoke dust emission as the environmental indexes and per capita GDP as the income index with 28 provincial data from 1993 to 2005. The results show that: (1) Pollution has spatial dependence in China and spatial panel data model is more suitable for studying the Environmental Kuznets Curve; (2) Considering spatial effect, the estimate result seems to be more robust than OLS estimate. Because the emissions of pollution are not only effected by the per capita income in the same region, but also largely impacted by the emissions from neighboring regions. (3) Resident environment quality-income is relatively low and does not take up a greater proportion in consumption demand.

  • Earth Surface Processes
    GE Zhao-shuai
    GEOGRAPHICAL RESEARCH. 2009, 28(3): 592-600. https://doi.org/10.11821/yj2009030004
    CSCD(6)
    Exploring the relationship between extreme floods in the Upper Changjiang River (UCR) and the southwest (SW) monsoon is of important theoretical and practical significance by means of the floods peak discharge. The climatic background of the extreme floods in the UCR was analyzed in this paper by recurring to 24 extreme Holocene floods and flood disaster data during the last 2000 years in Sichuan-Chongqing area. Summer SW monsoon is the main sources of precipitation in UCR. The flood caused by violent storm is the major flood type in UCR. The extreme floods in the UCR are related to the abnormal enhancement of SW monsoon. The analogism was employed for exploring the response of extreme floods to the Holocene climate change. The Holocene climate change information recorded in North Atlantic Ocean drilling core, Dongge stalagmite, Arabian sea drilling core and other proxies were used for analyzing the subjects. Based on the analysis of the relationship between the series of extreme floods in the UCR and the SW monsoon change during Holocene recorded by the marine core in the Arabian Sea, the extreme floods were greatly consistent with the SW monsoon change. The extreme floods event period during Holocene, characterized by the rapid climate change, were mostly the stage of strong climatic fluctuation or the climatic transition period. In comparison of the extreme floods to the climate change recorded in the North Atlantic Ocean, all the extreme flood periods are not consistent with the rapid climate change, which is similar to the scenario of the stalagmite in Dongge Cave in Guizhou Province. It is indicated that the flood event affected by the hydrologic-meteorologic process tended to be a local event. Compared with the flood disasters recorded in historical documents, the extreme floods with greater peak discharge and low frequency responded to the climate change very well, whereas the floods with small peak discharge and low frequency were more random. There were great differences in magnitude of historical floods recorded in documents. Therefore we should do analyses to distinguish these events based on the data rather than mix them up. The latter may cover up the true mechanism of the extreme floods and their responses to the climate change.
  • Climate and Global Change
    REN Yu-yu, REN Guo-yu, QIAN Huai-sui
    GEOGRAPHICAL RESEARCH. 2009, 28(1): 36-44. https://doi.org/10.11821/yj2009010006

    This paper projects future change in provincial climate-sensitive components of energy consumption of China, which resulted from the anthropogenic climate change and socio-economic development. The climate scenarios for 2020-2029 and 2050-2059 are obtained from seven IPCC AOGCMs simulations. The result shows that, by 2021-2030, the degree-days increase, compared with 1990-1999, in the south of China and decrease in the north of China. The situation for 2050-2059 is very similar to 2020-2029 in spatial patterns but the change magnitude is bigger. To climate-sensitive components of energy consumption, for 2020-2029 the increment is the largest in southern China and eastern coastal region, including the lower reaches of the Yangtze River. For the 2050-2059 scenario, the increase occurs in the south of China and the Bohai Sea Rim, while the decrease occurs in the center of China, part of western China and the north of northeast China. The special change value of climate-sensitive components of energy consumption of provinces in the same climatic province is different because the change of climate-sensitive components of energy consumption depends on not only climate change but also socio-economic development. Compared to the 2020-2029 scenario, provinces with a rising trend in climate-sensitive components of energy consumption increase in number in 2050-2059. Future climate-sensitive components of energy consumption still need further study due to the limit of present data and methods.

  • Environment and Ecology
    WU Yong-jiao, MA Hai-zhou, DONG Suo-cheng
    GEOGRAPHICAL RESEARCH. 2009, 28(2): 311-320. https://doi.org/10.11821/yj2009020005
    CSCD(4)

    This study aims to disclose dynamic relationship among socio-economic development, land use and eco-environment efficiency by proposing a response model of eco-environment to urban expansion. Firstly, we quantitatively describe the changes of land use from urban expansion by using the technology of remote sensing image interpretation. Secondly, dynamic relationship between eco-environment efficiency and socio-economic development is simulated through proposed model which is constructed based on theories of the maximum social welfare and Green GDP (GGDP). The proposed model is applied to Xi'an, China. Our model proves to be efficienct in simulating the dynamic relationship among land use, economic growth and eco-environmental efficiency through the analysis of urban expansion process in Xi'an. Results show that urban expansion will make the social welfare better only if marginal eco-environment cost caused by the urban expansion is less than the average land use; the improved technology and technological innovation can reduce eco-environment cost and increase land use efficiency, thus postpone the terminal of urban expansion. The simulated result shows that the urban expansion of urbanization process in Xi'an should be suspended in 2024 under the current situation.

  • Environment and Ecology
    XU Xin-wang, PAN Gen-xing, WANG Yan-lin, CAO Zhi-hong
    GEOGRAPHICAL RESEARCH. 2009, 28(3): 601-612. https://doi.org/10.11821/yj2009030005
    CSCD(32)

    Through collecting 966 samples of measured data of farmland topsoil organic carbon, as well as temperature and precipitation data from 1980 to 2006 of China, this paper analyzed changing characteristics of farmland soil organic carbon of China, discussed the reasons of change and development trends, and analyzed the differences of carbon sequestration ability of the temperature and rainfall on the paddy soil and dry soil, and the affection of temperature and rainfall on the soil organic carbon in different regions. The results show that farmland topsoil organic carbon of measured points presents upward trend overall, with 79% of increase samples mainly concentrated in the rise of 0~3% range. Soil organic carbon content was subject to climatic factors of temperature and precipitation, and the combination of hydrothermal conditions. Over the past 20 years, the distribution patterns of farmland topsoil organic carbon content remains unchanged. The change of farmland soil organic carbon was mainly affected by the impact of human activities. The difference of land use on soil carbon sequestration was significant, the level paddy soil organic carbon was significantly higher than the dry land, and the content of paddy topsoil organic carbon was 175%~176% of that of dry land.

  • Climate and Global Change
    ZHOU Qi, YU Yao-chuang
    GEOGRAPHICAL RESEARCH. 2009, 28(1): 45-54. https://doi.org/10.11821/yj2009010007
    CSCD(30)

    Public perception of climate change can support the development of adaptation strategy. By comparing the questionnaire survey results with climate data, this paper revealed the perception difference to the local air temperature and precipitation in the Guanzhong area. The results show that: (1) the local residents' perceptions of temperature and precipitation changes are in accord with, and proportionate to the real data; (2) the residents' perception intensities to the local temperature in the eastern and western Guanzhong area show an increasing trend with the aged becoming small, while the central part is opposite; the perception intensities to the precipitation, the central and western areas are a decreasing trend,while the eastern is opposite; (3) The deviations exist between the resident's perception and the real data changes. In contrast to the real data, the consistent ratings of the residents' perception to temperature changes in the eastern, central and western Guanzhong area are 37.5%, 75%, 37.5%, respectively; to the precipitation changes' consistent ratings is 50% each.

  • Earth Surface Processes
    ZHOU Chun-lin, YUAN Lin-wang, LIANG Zhong, YOU Hai-ning, YU Zhao-yuan, LIU Ze-chun
    GEOGRAPHICAL RESEARCH. 2009, 28(2): 321-332. https://doi.org/10.11821/yj2009020006
    CSCD(1)

    The famous fossil site of Hulu cave in Tangshan, Nanjing, is yielding Homo erectus fossils. Relative to the whole study of Homo erectus in Hulu cave, it is the weak link to study the cave deposit and its evolution. Combining with the achievements in chronology research, this paper analyzes the records of the oxide of cave clastic deposit and the fossils of phytolith from four sections with statistical methods, and clarifies the facts of the stratum contrastive relativation of each section. Besides, with the ground penetrating radar (GPR) method, the spatial structure and characteristic of the deposits of the eastern cave have been renewed, and on the basis of the characteristics of the cave clastic sediments, the constructive framework of the cave sections and cave embedding clastic sediments has been set up. The cave sediments in Tangshan, Nanjing have been identified into 7 layers from the bottom to the top as follows: (1) the lower breccia layer in the bottom of the cave, (2) the earth layer containing the breccia deposit, (3) the mid breccia layer, (4) the clastic earth layer, (5) the upper breccia layer, (6) the clastic clay layer, and (7) the pyramidal clastic breccia layer. Among them, the strata where the No.1 skull of Nanjing Man existed could be re-correlated with Layer ③. As the result of the evolution of paleo-climate and environment, the change of dynamic system of cave inside and the effect of local adjustment of erosion datum plane, the development of Hulu cave sediments can be divided into five stages as follows: (1) the erosion deposit stage of the northern cave, (2) the erosion deposit stage of the eastern cave, (3) the erosion deposit stage of the southern fissure cave, (4) the pyramidal deposit stage of the central cave, and (5) the erosion deposit stage of the western cave. The cave evolution could change with the space-time, and it is not so fit for living, thus it reflects that Hulu cave is not a good place for the ancient people. Based on the above researches, the paper provides the new visual angle and methods to discuss and analyze the evolution of karst cave, living age and environment of Homo erectus in Nanjing and further archeology.

  • Environment and Ecology
    SHAO Jing'an, SHAO Quan-qin, LIU Ji-yuan
    GEOGRAPHICAL RESEARCH. 2009, 28(3): 613-624. https://doi.org/10.11821/yj2009030006
    CSCD(4)
    Soil formation plays an important role in ecosystem sustainable functions under MA framework. This paper, by GIS-based spatial analysis, measured the sustainable functions of ecosystems in the three river sources, through soil preservation indicators. These results suggested that, in the three river sources, the features of different ecosystems determine the basic patterns of soil formation and sustainable functions of ecosystems. These patterns present lower tendency, along the orientation from southeast to northwest. The functions of soil preservation are significantly different among different ecosystems, in the order of wetland>forest and grassland>farmland>desert and bare land and bare rock. The sustainable functions of ecosystems decline in the order of wetland, forest, grassland, farmland, desert and bare land and bare rock. The patterns of grassland degradation are consistent with the distributions of soil preservation. Grassland degradation results in the reduction of ecosystem sustainable functions. Strong human disturbances cause the degradations of soil properties of each type, and induced the decline of the functions of soil formation and sustainable ecosystem. Our findings suggest that it may be useful to understand the sustainable functions of ecosystems from the aspect of soil formation.
  • Hydrology and Water Resources
    JIANG De-juan, LI Li-juan, HOU Xi-yong, LIANG Li-qiao, ZHANG Li, LI Jiu-yi, XU Ming-xing
    GEOGRAPHICAL RESEARCH. 2009, 28(1): 55-65. https://doi.org/10.11821/yj2009010008
    CSCD(12)

    Taking the middle and upper Tao'erhe River Basin as a study area, this paper analyzes variations of runoff, precipitation and temperature, etc. for the period 1961-2000. Time series analysis of characteristic parameters is used to examine the influences of climate change and land use and land cover change (LUCC) on runoff. And the response of runoff to water resources development (extraction for use) is estimated quantitatively based on the comparison between the observed and natural runoff data of Taonan hydrological station during 1961-2000. Some conclusions are drawn as follows: (1) The observed mean annual runoff is 38.2 m3/s for the past four decades, showing a trend of decrease - increase - decrease. The interannual and seasonal variations of runoff are greatly notable and the mean monthly runoff shows an unobvious trend according to the analysis result with the Kendall method. Over the period, annual precipitation has increased slightly to 427 mm. December's mean precipitation has increased significantly by the analysis result with the Kendall method. The mean annual temperature is 5.48℃ with a much greater value in the second half of the period (1986-2000); (2) The annual natural runoff is positively correlated with annual precipitation, and negatively correlated with annual temperature, and these relationships become weaker over time. Therefore, the increase of annual natural runoff coefficient under the same precipitation frequency may have mainly resulted from the decreasing vegetation cover. A wet year would have more impact on runoff than a dry year; (3) Water resources development decrease the annual runoff depth by 21.2 mm during the period 1986-2000, accounting for 37.1% of the mean annual natural runoff over the 40 years.

  • Earth Surface Processes
    JIAO Jian, XIE Yun, LIN Yan, ZHAO Deng-feng
    GEOGRAPHICAL RESEARCH. 2009, 28(2): 333-344. https://doi.org/10.11821/yj2009020007
    CSCD(16)

    Severe soil erosion has threatened land resources in Northeast China. Distributed at mid- and high latitudes, soil loss caused by snowmelt runoff plays a main part in soil erosion in this region. But there is little research on it. In this study, the characteristics of snowfall and snow cover were studied by using daily precipitation records from 93 climate stations, and the characteristics of snowmelt runoff and sediment yields were analyzed based on daily runoff and sediment yield data from 27 typical hydrological stations. The results showed that the snow period was 5-8 months and the snow cover period was 3.5-7 months in Northeast China, which prolonged gradually from south to north for both of the periods. The average proportion of snowfall to annual precipitation was 7%-25%, which caused 13.3%-24.9% of snowmelt runoff and 5.8%-27.7% of snowmelt sediment yields over the whole year. Although the snowmelt sediment transport modulus did not have significant relationship with snowfall, the distribution of snowfall and rainfall in a year had great influence on the ratio of snowmelt sediment yields to the year's total. The topography has great impacts on snowmelt sediment transport modulus. The snowfall and snowmelt runoff are less in hilly regions than in mountainous regions, but the sediment transport modulus in hilly regions was 2.9 times higher than that in mountainous regions. The sediment transport modulus (ST) has a good power function with the watershed area (S): ST=797.62S-0.6395. This trend is more apparent in hilly regions, while in the mountainous regions, the relationship between them is complex. The analyzed runoff and sediment yields in this paper were based on the observations in the hydrological stations which did not include deposited part before flowing into the river. It is necessary to strengthen the monitoring of runoff and soil loss during snowmelt season in order to get a better understanding of snowmelt erosion and mechanisms of causing factors.

  • Environment and Ecology
    ZHENG Zhi-qing, XIE Xiao-bao, OUYANG You-sheng, WANG Chun-hua, ZENG Hai-yan, CHEN Yi-ben
    GEOGRAPHICAL RESEARCH. 2009, 28(3): 625-633. https://doi.org/10.11821/yj2009030007
    CSCD(7)
    This paper, based on the fieldwork and statistical analysis, discusses the issues for the airborne microbes population and spatio-temporal variation in the urban agglomeration of the Pearl River Delta, Guangdong. Using geographical and ecological method, it aims at studying public health and environmental protection in the urban Pearl River Delta. Air sampling and environmental factors were carried out synchronously in four functional areas (key traffic route, commercial pedestrian street, residential district and industrial district) in eight cities (Guangzhou, Shenzhen, Zhuhai, Foshan, Jiangmen, Dongguan, Huizhou and Zhongshan) of the urban Pearl River Delta, Guangdong, in four different seasons from 2005 to 2007, with the aid of JWL-IIB Air-Borne Microbial Sampling Apparatus. The results are shown as follows: Firstly, the dominant population of fungi of airborne microbes has 19 genera and 21 species, such as Aspergillus sp. , Penicillium sp. , Cladosporium sp. , Clodosporium sp. and so on. The dominant population of bacteria has 4 genera and 15 species, including Bacillus, Staphylococcus, Exiguobacterium and Streptomyces. Secondly, the average content of airborne microbes(fungi and bacteria)in Guangzhou and Dongguan is higher than that of the other 6 cities in the urban Pearl River Delta, and the content of bacteria is higher than that of fugi. The average content of fungi and bacteria on the key traffic routes is higher than that of the other functional areas; outdoor content is higher than indoor content; the average content of airborne microbes in the areas without greenbelt is higher than in the areas with greenbelt; and the average content of airborne microbes is higher during spring and summer compared with the other two seasons. Finally, atmospheric pressure, wind speed, humidity, temperature, total suspended particulate (TSP), inhalable particles (PM10), population stream, vehicle stream and green space ratio are the important influencing factors of the average content of airborne microbes. Among them, average temperature and wind speed are the major factors affecting the content of atmospheric microorganism.
  • Hydrology and Water Resources
    CHENG Lei, XU Zong-xue, LUO Rui, MI Yan-jiao
    GEOGRAPHICAL RESEARCH. 2009, 28(1): 65-73. https://doi.org/10.11821/yj2009010009

    The SWAT is a physically-based distributed hydrological model. Its runoff generation mechanism is more practical. The methods adopted in the process of runoff including surface runoff, interflow and groundwater flow are applicable to various conditions of climate and underlying surface. In this study, the SWAT (Version 2005) is applied to the Kuye River basin, one of typical watersheds with plentiful and coarse sand in the middle reaches of the Yellow River with arid and semi-arid climate. When the model in the Kuye River basin was developed, automatic calibration method within the SWAT Version 2005 was used to calibrate the model. According to the stream flow hydrograph at Wenjiachuan station, the mouth of the river, the parameters were further adjusted. Then, daily and monthly discharges from 1980 to 1985 have been simulated in the study area, and observed data series of three hydrological stations (Wenjiachuan, Xinmiao and Wangdaohengta) are used to evaluate the simulated discharge series of SWAT. The effects of physical mechanism for streamflow generation processes have been analyzed and discussed. The result shows that the relative error of water budget is about 10%-20%, while the Nash-Sutcliffe efficiency coefficient (Ens) is relatively low, with Ens of daily series being about 0.2 and monthly Ens around 0.6. Preliminary analysis of simulation results showed that the SWAT is not effective to simulate the discharge of interflow, baseflow and spring flood in the Kuye River basin. In addition, it is proposed that the SWAT runoff generation mechanism in arid and semi-arid regions need to be further investigated.

  • Earth Surface Processes
    MA Yuan-xu, XU Jiong-xin
    GEOGRAPHICAL RESEARCH. 2009, 28(2): 345-353. https://doi.org/10.11821/yj2009020008
    CSCD(3)

    The hydraulic geometry is an effective tool in quantifying the relationship between channel morphology and hydraulic variables. The research on hydraulic geometry plays an important role in understanding the channel change caused by natural environment change and it can provide some insightful advice in river restoration and channel design. The study area is located in the Wuding River Basin. Using the data measured during the period 1959-1969, the hydraulic geometry relationships are analyzed for 34 cross-sections. The results show that the hydraulic geometry exponents can generally be categorized into three types: b>f & m>f & b+ f>m; bf & b+ f>m; bm. There are similar spatial scale effects for both mean width and mean width to depth ratio exponents, and an inverse relationship exists in mean depth relationship. There is no obvious correlation between mean velocity and drainage area. The differences of the hydraulic geometry exponents can be ascribed to different stream orders and channel functions. The streams of lower order originate from eroded areas, where erosion is the dominant process and thus, the channels are relatively shallow. The streams of higher orders are adjusted to transport imposed sediment, so the channels are narrower and deeper. In addition, the hydraulic geometry of some stream channels does not agree with the power function. The natural logarithm relations or quadratic relations may be good alternatives. This probably implies that the channel scour and fill lead to the instability of channel morphology.

  • Climate and Global Change
    MIAO Qi-long, DING Yuan-yuan, WANG Yong
    GEOGRAPHICAL RESEARCH. 2009, 28(3): 634-642. https://doi.org/10.11821/yj2009030008
    CSCD(33)

    Changes of the climatic zones are related to climate warming and its impacts. The northern boundary of sub-tropical zone is between the temperate and sub-tropical zones, which is a very important boundary in China's climatic divisions. In this paper a case study is made on the impact of climate warming on the northern boundary of sub-tropical zones of China. The data covering about 55 years (1951~2005) of daily mean temperature with 740 stations are obtained from China Meteorological Administration. According to the definition of the first class climatic zone from Climatological Atlas of the People's Republic of China, the authors use the number of days with secular pentad mean temperature passing through ≥10℃ as the main index, and January mean air temperature as the auxiliary indices. Namely the definition of the northern boundary of sub-tropical zone is the divide where the number of days with secular pentad mean temperature passing through ≥10℃ reaches 218, the accumulated temperature with ≥10℃ is 4500~4800℃, and January mean air temperature is 0℃. The authors count respectively the inter-decadal changes of indices of the first class climatic zone in north sub-tropical and temperate zones in 1951~2005, and the changes of the north sub-tropical belt in the periods 1951~1970, 1971~1990 and 1991~2005. The results show that: the number of days of secular pentad mean temperature passing through ≥10℃, the accumulated temperature ≥10℃ and January mean air temperature all have an upward trend in the 55 years in the vicinity of 34 degrees north latitude. Since the 1950s, there has been little change in the western section of the northern boundary of sub-tropical zone; the central and eastern sections of the northern boundary of sub-tropical zone moved to the north over a large range. By the beginning of the 21st century the central and eastern sections has moved to near 35°N, i.e., 2~3 degrees of latitude northward, compared with the period 1951~1970. The northern boundary of sub-tropical zone moving towards the north, which is a response to climate warming, will have a very important influence on the agricultural pattern and the ecological environment.

  • Hydrology and Water Resources
    WANG Yu-juan, YANG Sheng-tian, LIU Chang-ming, DAI Dong, ZHENG Dong-hai, ZENG Hong-juan
    GEOGRAPHICAL RESEARCH. 2009, 28(1): 74-84. https://doi.org/10.11821/yj2009010010

    In recent years, regional vegetation water use has been a new and "hot" field in ecology, hydrology and water resources, especially in the arid and semiarid regions. Economic development of the Yellow River Basin is based upon energy, heavy chemical industry, grain and cotton. These activities, combined with climate change, have resulted in a shortage of water resources. In this paper, an eco-hydrological model was constructed to simulate the regional vegetation water use. The patterns of eco-water use by vegetation in Sanmenxia area of the Yellow River were studied using RS and GIS technology, TM data, meteorological data, observed data and vegetation and soil texture information. On the basis of the patterns of regional vegetation water use, the availability of green water are analyzed for different vegetation types. The results are as follows: due to the variation of climate and land cover, the eco-water use of vegetation has had a trend of decreasing-stable-increasing in Sanmenxia area since the 1950s; different vegetation types have different patterns. Forest, shrub, grass and farmland were chosen to compare eco-water amount, indicating forest>corn field>shrub>grass. Among them, the forest has the highest utility of green water, followed by grassland, shrub and farmland. Based on these calculations and analyses, the countermeasures suggested for high-efficiency use of water and land resources are: to adjust vegetation structure and crops structure to realize optimal allocation of water resources.

  • Climate and Global Change
    JIANG Xiao-yan, LIU Shu-hua, MA Ming-min, ZHANG Jing, SONG Jun
    GEOGRAPHICAL RESEARCH. 2009, 28(2): 354-362. https://doi.org/10.11821/yj2009020009
    CSCD(58)

    In recent 100 years, global warming is increasing remarkably, and there are even greater uncertainty, changing precipitation trend and regional differences. In this study, a wavelet analysis method of Morlet is used to research the periodical regulations at different time scales of the precipitation time series during the latest nearly 100 years in Northeast China. Based on the monthly and annual precipitation data of Harbin, Shenyang, Changchun and Dalian weather stations covering the period from 1905 to 2005, the periodic oscillation of precipitation and the points of abrupt change at different time scales along the time series are discovered and the main periods of every serial are confirmed. The result shows that the precipitation of Northeast China has a decreasing trend, with rates of -5.2mm/10a, and -12.7mm/10a, -7.1mm/10a, -2.7mm/10a, 1.3mm/10a for Northeast China, Changchun, Harbin, Dalian and Shenyang respectively. There are multi-time scales of periodical change, which present appears different traits at different phases. There are periodic oscillations of 2a-3a, 5a-6a, 10a and 50a for the seasonal and annual precipitation variations. The local characteristics of time-frequency for wavelet analysis can demonstrate the detailed structures of precipitation. The wavelet analysis can be an alternative approach to the analysis of climate multi-time scales characteristics and the forecast of short-term climate variations.

  • Climate and Global Change
    FAN Ze-meng, YUE Tian-xiang, SONG Yin-jun
    GEOGRAPHICAL RESEARCH. 2009, 28(3): 643-652. https://doi.org/10.11821/yj2009030009
    CSCD(14)
    Temperature and precipitation are the major climatic factors. Their changing trends have direct impact on the structure, service function and distribution of various ecosystems. To obtain the high accuracy surface information of temperature and precipitation, this paper introduces the YUE-HASM on the basis of the fundamental theorem of surfaces and multigrid method, which would be developed into a general platform that would have much stronger capacity of spatial modeling and make better use of the existing data. YUE-HASM has quickened computational speed and greatly increased simulation accuracy, compared to the commonly used methods (e.g. Kriging used in this paper). The number test shows that it is much more accurate than common methods, so in this paper, the YUE-HASM method is used to simulate the changing trend of annual mean temperature and annual mean precipitation in Jiangxi Province during the period from the 1960s to 1990s. The results show that: 1) the mean temperature and the mean precipitation only respectively increased by 0.02℃ during 1961~2000, but during the 40 years, the spatial and temporal distribution of temperature and precipitation in Jiangxi Province has presented a significant change; 2) it is a relatively warm and dry period in the 1960s; 3) it is a relatively cold and humid period from the 1970s to 1980s; and 4) it is a warm and humid period in the 1990s. From the 1960s to 1970s, the mean temperature decreased by 0.27℃ and the mean precipitation increased by 133.11mm. From the 1970s to 1980s, the mean temperature decreased by 0.04℃ and the mean precipitation only increased by 5.02mm. From the 1980s to 1990s, the mean temperature increased by 0.39℃ and the mean precipitation increased by 170.57mm. From the above analysis and discussion, it can be concluded that YUE-HASM would be an essential part of ecological informatics that studies the fundamental issues arising from the creations, storage, processing, analyzing, and modeling of the ecological information.
  • Land Resource and Use
    JI Min-he, Michael Monticino, Miguel Acevedo
    GEOGRAPHICAL RESEARCH. 2009, 28(1): 85-96. https://doi.org/10.11821/yj2009010011
    CSCD(4)

    Residential development is a major driving force in the dynamics of urban land use and ecosystems. The type and rate of land development depend on the complex interaction among the stakeholders and their responses to the environmental consequences after a development decision is made. This paper introduces a framework of a coupled human and natural system and uses a multi-agent model to simulate the complex interactions among land stakeholders with respect to the decision making process for local land development. The human system was built on a multi-agent model, with each class of agents representing different types of landowners, homeowners, municipal government, and commercial developers, respectively. The decision making process of each agent class was modeled using an agent-specific multi-attribute utility function. The complex interactions among different classes of agents as well as among the agents of the same class were simulated with a given time lag in sequence. The natural system was built on a cellular automata platform, where the land cover transition rules were governed by a landscape model (MOSAIC) and a patch model (FACET). The environmental quality indices to be used as feedback to the human system were generated from a hydrological model and a habitat model. In each lifecycle of simulation, human decisions on land development were passed to the natural system, which in turn generated environmental indices to be considered by the concerned agents (such as homeowners and the government) in the land-related decision making in the next cycle. Using a fast-urbanizing region in northern Texas as the study area, the model was run to produce simulations with a 25-year time span. Preliminary results demonstrated the ability of the model in simulating real dynamic situations at the qualitative level. It revealed a cyclic trend of interactions among agents, which was also observed in the real situation, with landowners and homeowners being the most active agent types. In addition, this study tested several land management strategies and revealed that considering landowner values when targeting available open space for preservation may lead to more effective growth management strategies than solely purchasing land based on opportunity or ecological factors. Extensive efforts are also required when applying this modeling framework to different socioeconomic and cultural settings, such as China.

  • Climate and Global Change
    CHEN Ying-yu, JIANG Fu-chu
    GEOGRAPHICAL RESEARCH. 2009, 28(2): 363-370. https://doi.org/10.11821/yj2009020010
    CSCD(5)

    This paper studied the responses of the environment to the climatic changes by using the temperature and precipitation data at Gonghe station covering the period from 1953 to 2005. The results show that: (1) The annual average temperatures in the area showed a marked increasing trend, with a rate of about 0.28℃ per 10 years, higher than the mean values for China and the whole world. The seasonal temperatures and precipitation showed different increasing trends. The temperatures rose more significantly in autumn (from September to November) and winter (from December to next February), while spring (from March to May) and summer (from June to August) witnessed a slower temperature increase. The annual precipitation showed a slight increasing trend. In summer and autumn, the precipitation showed a tendency to decrease year by year, and more marked decrease was recorded in autumn. However, in spring and winter the precipitation shows a tendency to increase year by year. (2) The warmer and drier climate is the key factor leading to the environmental problems such as desertification, grassland degradation, frequent disasters and decreasing runoff, which have had great effects on the socio-economic development and environment in this area. (3) The Gonghe basin is one of the sensitive and vulnerable areas to the climate change on the Tibetan Plateau and even in the world.

  • Climate and Global Change
    LEI Yang-na, GONG Dao-yi, ZHANG Zi-yin, GUO Dong, HE Xue-zhao
    GEOGRAPHICAL RESEARCH. 2009, 28(3): 653-662. https://doi.org/10.11821/yj2009030010
    CSCD(15)

    Based on the data for 193 meteorological observation stations in eastern China from 1955 to 2005, the authors analyzed the spatial and temporal characteristics of summer high-temperature events (daily maximum temperature above 35℃). Empirical orthogonal function (EOF) analysis reveals that there are three main patterns for the high-temperature events. The first EOF pattern is Characterized by a uniform anomaly over the whole east China with a center along the Yangtze River valley.The second is a dipole pattern with two centers in southernmost China and the areas to north, and the third mode shows an out of phase pattern between east and west parts of the area. These patterns are tightly related to the atmospheric circulation. The results show that ENSO, Equatorial Indian Ocean and Western Pacific Warm Pool SST could affect the frequency of summer high temperature by influencing the Western Pacific and East Asia atmospheric circulation. ENSO and Western Pacific Warm Pool have a great impact on the first EOF. And the relationship between the second EOF and Equatorial Indian Ocean SST is a significantly negative correlation. The relations between high temperature and the preceding SST of "key regions" are studied; there are evident positive correlations between the preceding summer SST of Western Pacific Warm Pool and the first EOF, which is negatively correlated with the preceding winter SST of Equatorial East Pacific. And the second EOF is most impacted by the preceding winter SST of Equatorial Indian Ocean.

  • Land Resource and Use
    QU Ai-xue, BIAN Zheng-fu, ZHU Chuan-geng, MA Xiao-dong, MENG Zhao-yi, LI Zhi-jiang
    GEOGRAPHICAL RESEARCH. 2009, 28(1): 97-109. https://doi.org/10.11821/yj2009010012
    CSCD(21)

    Both rapid urbanization and industry conversion based on the life cycle of resource have great effects on the land use change and pattern of mining cities. So, land use change in mining cities was a special process strongly affected by the human-land relationship. Therefore, based on LANDSAT TM remote sensing images in 1987, 1994, 2000, 2003, 2007, and on maps of urban land use status in 1994 and 2003, database was established on land use of the mining city--Xuzhou urban area. Then features on the process and pattern of land use change were disclosed by using quantitative change models such as dynamic degree, intensity, LUD, LUC and spatial analysis methods including gravity center changes, interpolation analysis, spatial differentiation and fan analysis. Further, the mechanism of land use change was analyzed. Results show that: (1) Farmland keeping reducing and built-up land keeping increasing was the main characteristic of the land use change. Therefore, on one hand, we should meet the need of rapid urban land expansion, on the other hand we should strengthen arable land protection. (2) The spatial distribution of built-up area expansion showed the step character from separated patch increasing, radial infill expansion to allometric expansion and double-center evolution. Further study should be done on the time-space pattern of land use in mining cities. (3) Land use change resulted from several factors. Natural conditions will take effect a long time. Mineral resources were always playing an important role in the shape and the evolution of land use. Economic factors, such as industrialization, urbanization and adjustment of industrial structure, were the leading force of the land use structure evolution. Under this background, city spatial planning, especially the rational planning of the industrial zones, economic development zones and the new city zones were the important force of built-up expansion evolution. Transportation, especially rapid transit network was a strong traction force of land use changes. (4) Land use pattern was affected by the distribution of the mineral resources and spatial pattern evolution of mining city land was affected by the life cycle of mineral resources. Mineral resources together with natural conditions and economic factors always had great effects on mining city land use. As mineral resources exhausted, adjustment of land use structure should be speeded up in mining cities. (5) Methods need to be improved for further study on the characteristics and the mechanisms of mining cities.

  • Climate and Global Change
    HOU Peng, JIANG Wei-guo, CHEN Zi-li, LUO Ai-min
    GEOGRAPHICAL RESEARCH. 2009, 28(2): 371-378. https://doi.org/10.11821/yj2009020011
    CSCD(4)

    Wetlands exist in a transition zone between aquatic and terrestrial environments which can be altered by subtle changes in hydrology. Hydrological process determines the formation, development and succession of wetlands. Taking the Dongting Lake as a study area, this paper studies the hydrological recharge effect of the atmosphere precipitation. According to the meteorological data, remote sensing image and typical underlay feature data, the recharge effectivity of the rainfall on the Dongting Lake wetland is analyzed supported by GIS (geographical information system) technology and SCS (Soil Conservation Service) model. Based on the analysis of spatio-temporal feature of rainfall and modeling of the runoff of precipitation, we obtained ARC (area recharge coefficient) and VRC (volume recharge coefficient). Thus, ARC well explains the acreage relationship of watershed and that of the water area in the lake sometime. It presents not only the wetland hydrology feature depending on the recharge water, but also the recharge effect of the runoff coming from rainfall and its influence on the water area. However, it is difficult to illustrate water fluid in wetland resulting from precipitation recharge in a period. Considering the relationship between flux of rainfall-runoff and volume of lake, VRC is calculated to make up for the shortcoming of ARC. According to the model, the recharge effectivity of rainfall can be computed in a certain period. ARC, together with VRC, can better explain runoff coming from rainfall as well as how it affects Dongting Lake's hydrological process and how it recharges water to the wetland, including the water area and water cycle. Thus it is significant to realize the importance of rainfall to the wetland and to protect and manage Dongting Lake wetland.

  • Climate and Global Change
    GU Jing, ZHAO Jing-bo, ZHOU Jie, ZHANG you-yin
    GEOGRAPHICAL RESEARCH. 2009, 28(3): 663-672. https://doi.org/10.11821/yj2009030011
    CSCD(5)

    Based on the historical materials in the Yuan Dynasty in Jinghe and Luohe drainage basins, this paper analyzed the sequence, temporal change and the cause of drought disasters. The results indicated that the Jinghe and Luohe drainage basins suffered from 29 drought disaster events in total, averaged one occurrence every 3.2 years during the 94 years from the early to late Yuan Dynasty (1266AD-1359AD). The drought disasters in the Yuan Dynasty in the Jinghe and Luohe drainage basins were mainly slight ones, which accounted for 44.8% of the total, followed by moderate drought disasters accounting for 37.9% of the total. The occurrence of the severest ones was also higher, being 13.8%, and that of heavy drought disasters were the lowest, or 3.5%. There were diverse changes in the occurrences of drought disasters during the early, middle and late Yuan Dynasty in the Jinghe and Luohe drainage basins. Summer droughts were the main type, followed by spring drought. The successive occurrences of spring and summer droughts as well as four seasons were also higher, only next to spring droughts. The intra-annual variations in the temperature and precipitation were the main cause of the slight and moderate drought disasters. The climatic trend toward drought resulted in the heavy and severest ones during the middle Yuan Dynasty in the two basins. Thus we infer that there was one drought event in the Yuan Dynasty in the Jinghe and Luohe drainage basins, occurring between 1326~1332. Initially, we determined that yearly average precipitation of heavy drought disasters was about 400mm and yearly average precipitation of the severest drought disaster was about 350mm in the main drought disaster areas.