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    Climate Change
  • Climate Change
    LIU Yi, YANG Yu, LI Li
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    Based on historical documents and records this paper analyzes the characteristics of frequency and distribution of major disasters that took place in the history of China. The findings show that occurrences of different types of disasters varied and spatial pattern at provincial level are significantly different as well. The results also indicate that there is a strong relationship between type of disasters and spatial distribution and that the spatial pattern of losses was not the same as that of the frequency. The reasons are: (1) the hazard-formative environments which, to a large extent, determine the spatial pattern of the disasters are significantly different; (2) the losses caused by natural disasters were closely related to the concentration of economy and population. Number of deaths was usually large in areas where agriculture, culture and business were relatively developed. The spatial pattern of disaster losses is an evitable result of uneven economic development in the history of China.

  • Climate Change
    MA Xuening, ZHANG Mingjun, LI Yaju, WANG Shengjie, MA Qian, LIU Wenli
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    According to the meteorological observation data of 72 stations from 1960 to 2010 in the Huanghe (Yellow) River Watershed, China, the long-term variations of potential evapotranspiration, calculated in the modified Penman-Monteith model of Food and Agriculture Organization of the United Nations, were presented, as well as the meteorological causes for the decrease of potential evapotranspiration were discussed. Since 1960, temperature has risen significantly and potential evapotranspiration a decreasing trend, which indicated the existence of “Evaporation paradox” in the Huanghe River Watershed. This phenomenon was not consistent spatially or temporally with the increase of temperature, potential evapotranspiration decreased in spring, summer and winter, mainly over most parts of Shanxi and Henan, and some parts of Gansu, Ningxia, Inner Mongolia, and Shaanxi. During the recent half century, the trends of temperature and potential evapotranspiration were negatively correlated at most of the stations, while precipitation and potential evapotranspiration exhibited a contrary trend. Calculated in multiple regressions, the contribution to potential evapotranspiration change of related meteorological factors was discussed, including mean pressure, maximum and minimum temperature, sunshine hours, relative humidity and average wind speed. The decrease of wind speed in the Huanghe River Watershed may be the dominating factor causing potential evapotranspiration decreasing.

  • Climate Change
    FAN Lan, LU Changhe, YANG Biao, CHEN Zhao
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    The North China Plain (NCP) is the most important food grain producing area in China and has suffered from serious water shortages. To capture variation water availability, it is necessary to have an analysis of changing trends in precipitation. This study, based on daily precipitation data from 47 representative stations in NCP records passed the homogeneity test, analyzed the trend and amplitude of variation in monthly, seasonal and annual precipitation, annual maximum continuous no-rain days, annual rain days, rainfall intensity, and rainfall extremes from 1960 to 2007, using the Mann- Kendall (M-K) test and Sen’s slope estimator. It was found that monthly precipitation in winter had a significant increasing trend in most parts, while monthly precipitation in July to September showed a decreasing trend in some parts of NCP. No significant changing trend was found for the annual, dry and wet season precipitation and rainfall extremes in the majority of NCP.A significant decreasing trend was detected for the maximum no-rain duration and annual rain days in the major part of NCP. It was concluded that the changing trend of precipitation in NCP had an apparent seasonal and regional pattern, i.e., precipitation showed an obvious increasing trend in winter, but a decreasing trend in the rainy season (July to September), and the changing trend was more apparent in the northern part than in the southern and middle parts. This implies that with global warming, seasonal variation of precipitation in NCP tends to decline with an increasing of precipitation in winter season, and a decreasing in rainy season, particularly in the sub-humid northern part.

  • Climate Change
    LIU Yujie, TAO Fulu
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    Impacts of climatic change on agriculture and adaptation are of key concern of scientific research. However, vast uncertainties exist among global climates model output, emission scenarios, scale transformation and crop model parameterization. In order to reduce these uncertainties, we integrate output results of four IPCC emission scenarios of A1FI, A2, B1 and B2, and five global climatic patterns of HadCM3, PCM, CGCM2, CSIRO2 and ECHAM4 in this study. Based on 20 databases of future climatic change scenarios from the Climatic Research Unit (CRU) , the scenario data of the climatic daily median values are generated on research sites with the global mean temperature increase of 1℃(GMT+1D), 2℃(GMT+2D) and 3℃(GMT+3D). The impact of CO2 fertilization effect on wheat biomass for GMT+1D, GMT+2D and GMT+3D in China’s wheat-producing areas is studied in the process model, CERES-Wheat and probabilistic forecasting method. The research results show the CO2 fertilization effect can compensate reduction of wheat biomass with warming temperature in a strong compensating effect. Under the CO2 fertilization effect, the rain-fed and irrigated wheat biomasses increase respectively, and the increment of biomass goes up with temperature rising. The rain-fed wheat biomass increase is greater than the irrigated wheat biomass. Without consideration of CO2 fertilization effect, both irrigated and rain-fed wheat biomasses reduce, and there is a higher probability for the irrigated wheat biomass than that of the rain-fed wheat biomass.

  • Hydrology
  • Hydrology
    LIU Feng, CHEN Shenliang, DONG Ping, PENG Jun
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    Water discharge data of the Yellow River over the past 60 years was analyzed using the continuous wavelet transform (CWT) and Mann-Kendall (MK) test methods to identify spatial and temporal variation patterns. Potential connections between water discharge in the Yellow River Basin and El Niño/Southern Oscillation (ENSO) were also examined by the cross wavelet and wavelet coherence methods. CWT results show that the periodic oscillations in water discharges had occurred at the temporal scales of 1-, 2- to 4-, 6- to 8- and 10- to 22-year. It was also found that at the annual timescale (1-year) the phase relations between water discharge and ENSO were indistinct probably due to the strong influence by human disturbances. However, over the longer time scales, the phase relation becomes much clearer with an anti-phase relation being found mainly at inter-annual scale (2- to 8-year) and in-phase relation at decadal scale (16- to 22-year). According to the MK test results water discharge at most stations except Tangnaihai have decreased significantly and the abrupt change occurred in the mid-1980s or the early 1990s. The changes in water discharge were found to be influenced by both climate changes and human activities. Before 1970 the change in water discharge was positively related to precipitation variations in the river basin, but after 1970 the decrease in water discharge has been largely caused by various human activities including constructions of reservoirs, water abstraction and water-soil conservation with water abstraction being the main cause.

  • Hydrology
    LIU Xinyou, HE Daming
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    The environmental impact assessment (EIA) of cascade dams building in international rivers has been widely discussed in China and ASEAN countries since the 1990s. In Southwest China, all the great mountainous rivers have been the major state base for large-scale hydropower development. Among these rivers, the environmental change and response of the watercourse under the cascade dams building in the upper Mekong (called Lancang River in China) has been the focus in recent 20 years. In this paper, the Lancang River, which has over 25 years of large-scale hydropower development, was chosen as a case study for establishing the affected evaluation indicators system and its regression model of runoff and sediment, determining the indicators weight by the hierarchy analysis method and factor analysis method, and setting up the quantitative evaluation models of indicators affected level based on the "marginal efficiency" principle. Using these methods and model established, the influence degree of runoff and sediment in the Lancang River from 1986 to 2007 were assessed. The major results are: (1) the impact of sediment transport change by the cascade development is much higher than that of the runoff change; (2) the years’ number with different impact levels respectively are 72.7% as the “smallest” level, 18.2% as “smaller”, and 9.1% as “general”; (3) the change process of runoff and sediment shows a “U-shaped” pattern, which indicates the balance of sediment change because of the interaction of sediment reduction by Manwan reservoir storage and the increase by the Dachaoshan dam construction.

  • Hydrology
    XIA Jun, DU Hong, ZENG Sidong, SHE Dunxian, ZHANG Yongyong, YAN Ziqi, YE Yan
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    Based on the daily runoff data from 20 hydrological stations above the Bengbu Sluice in the Huaihe River Basin during 1956-2010, run test, trend test and Mann-Kendall test are used to analyze the variation trend of annual maximum runoff series. The annual maximum series (AM) and peaks over threshold series (POT) are selected to describe the extreme distributions of generalized extreme value distribution (GEV) and generalized Pareto distribution (GPD). Temporal and spatial variations of extreme runoff in the Huaihe River Basin are analyzed. The results show that during the period 1956-2010 in the Huaihe River Basin, annual maximum runoff at 10 stations have a decreasing trend, while the other 10 stations have an unobvious increasing trend. The maximum runoff events almost occurred in the flood period during the 1960s and 1970s. The extreme runoff events in the Huaihe River Basin mainly occurred in the mainstream of the Huaihe River, Huainan mountainous areas, and Funiu mountainous areas. Through Kolmogorov-Smirnov test, GEV and GPD distributions can be well fitted with AM and POT series respectively. Percentile value method, mean excess plot method and certain numbers of peaks over threshold method are used to select threshold, and it is found that percentile value method is the best of all for extreme runoff in the Huaihe River Basin.

  • Human-Environment Interactions
  • Human-Environment Interactions
    SONG Xiaoqing, OUYANG Zhu, LI Yunsheng, LI Fadong
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    Cultivated land protection (CLP) entered the new era of macro administration in 1999 in China. This paper presents a holistic analysis of cultivated land use change concerning the three goals of the CLP, i.e., grain security, ecological security and harmonizing regional development. Farmers’ willingness to grow grain has been the key factor in safeguarding grain security. Grain-for-green policy has contributed to improving ecological state especially in the western provinces. Effects of the land macro-control of the CLP on harmonizing regional development were significant. Moreover, cultivated land use change in 1999-2007 points out the way of the evolving policy in the future. From the viewpoint of normative concept of multifunctionality, we discuss development of the three land functions, i.e., production function, environmental function and carrier function. Finally, we propose to emphasize multifunctional land management based on regional differences to promote transition of the CLP.

  • Human-Environment Interactions
    FU Qiang, ZHU Yunqiang, KONG Yunfeng, SUN Jiulin
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    The capacity of livestock breeding in China has increased rapidly since 1949, and the total output of meat, poultry and eggs maintains the world’s top first in recent 20 years. Livestock emissions and pollution is closely associated with its population and spatial distribution. This paper aims to investigate the spatial patterns of livestock and poultry breeding in China. Using statistical yearbook and agricultural survey in 2007, the county-level populations of livestock and poultry are estimated as equivalent standardized pig index (ESP), per cultivated land pig index (PCLP) and per capita pig index (PCP). With the help of spatial data analysis (ESDA) tools in Geoda and ArcGIS software, especially the Moran’s I and LISA statistics, the nationwide global and local clustering trends of the three indicators are examined respectively. The Moran’s I and LISA analysis shows that ESP and PCP are significantly clustering both globally and locally. However, PCLP is clustering locally but not significant globally. Furthermore, the thematic map series (TMS) and related gravity centers curve (GCC) are introduced to explore the spatial patterns of livestock and poultry in China. The indicators are classified into 16 levels, and the GCCs for the three indicators from level 1 to 16 are discussed in detail. For districting purpose, each interval between gravity centers of near levels for all the three indicators is calculated, and the districting types of each indicator are obtained by merging adjacent levels. The districting analysis for the three indicators shows that there exists a potential uniform districting scheme for China’s livestock and poultry breeding. As a result, the China’s livestock and poultry breeding would be classified into eight types: extremely sparse region, sparse region, relatively sparse region, normally sparse region, normal region, relatively concentrated region, concentrated region and highly concentrated region. It is also found that there exists a clear demarcation line between the concentrated and the sparse regions. The line starts from the county boundary between Xin Barag Left Banner and Xin Barag Right Banner, Inner Mongolia Autonomous Region to the west coast of Dongfang County, Hainan Province.

  • Human-Environment Interactions
    DUAN Jinlong, ZHANG Xuelei
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    Two typical provincial capitals (Nanjing and Zhengzhou) and two counties (Rugao and Yuanyang) in east (Jiangsu Province) and central (Henan Province) China were chosen respectively as the developed and less developed comparative cases for pedodiversity and land use diversity correlative analysis by borrowing the recently better developed pedodiversity methodology. Land use classification was worked out using remote sensing images in three different periods (1986-1988, 2000-2001 and 2004-2006) for these studied case areas before the calculation of the constituent diversity index and spatial distribution diversity index modified after Shannon entropy in 2 km×2 km grid scale of the soil and land use pattern were conducted and then a connection index was proposed to evaluate the relationship between soil and land use diversity. Results show that during the years from 1986 to 2006, the composition and spatial distribution of regional land use pattern had changed greatly. The agricultural land area of all the studied case areas decreased obviously in which Nanjing has the highest decrement of 895.98 km2 mainly into urban use while the other land use type area changes show the same trend. The connection index of four typical soil family types and typical urban land use types, i.e., urban construction land, transportation land and industrial and mining area all increased in this period. In the studied case areas, there is the highest soil constituent diversity in Zhengzhou at 0.779 while the simplest soil constituent diversity in Rugao at 0.582. Meanwhile we have higher land use diversity in the more urbanized Jiangsu Province than Henan Province, Nanjing is ranking the first that has been getting higher and higher in the three periods at 0.366 in 1986-1988, 0.483 in 2000-2001 and 0.545 in 2004-2006. Finally, the connection index figures to evaluate the relationship between soil and land use diversity of the studied areas were compared to show the similar phenomenon that this figure grows fastest in Nanjing followed by Zhengzhou and other places.

  • Human-Environment Interactions
    WANG Limao, GU Mengchen, LI Hongqiang
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    Marked by the UN Climate Change Conference in Copenhagen 2009, climate change is shaping the new pattern for future geopolitics with unprecedented drive. Climate change has surpassed the category of pure environment problem and become a focal issue in international relations. Driven by climate change, new changes have taken place in the evolution of geopolitical pattern. (1) Geopolitical contention expands into new fields and regions. (2) Measures and tools of geopolitical contention become more diversified. (3) Main bodies of geopolitical gambling are divided into different groups. With the development of politicization, climate change has become the significant driving force that can influence the evolution of geopolitical pattern. Measures, sphere and contents of geopolitical contention changed dramatically, carbon emission permits, carbon tariff and new energy technology turned into the key points of geopolitical contention. Climate change acts on the evolution of geopolitical pattern through three main paths: “Feedback effect”, “Trace back effect”, and “Ripple effect”, and they exert influence on geopolitical pattern with three impacts: “Depression effect”, “Traceability effect”, and “Diffusion effect”. We draw several conclusions from the analysis: (1) Climate change gradually becomes one of the most active driving forces to impact on the evolution of geopolitical pattern in the present world and it diversifies the geopolitical targets. (2) Climate change generates new geopolitical tools. The developed countries use climate change as a “Lever” to pry strategic resources like energy and grain and the geopolitical means are in a more secretive way. (3) Low-carbon technology, with new energy technology as the core, becomes the key factor of geopolitical influence and power transition. Those who can take advantage of new energy technologies will occupy the leading position in future’s climate change negotiations and geopolitical competition.

  • Human-Environment Interactions
    WANG Zheng, WU Jing, ZHU Qianting, WANG Lijuan, GONG Yi, LI Huaqun
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    Many global emission reduction strategies have been proposed, but few have been assessed quantitatively from the view of equality, efficiency and effectiveness. Integrated assessment models (IAM) is one of the effective ways to make climate policy modeling. So in this paper we developed the MRICES (Multi-regional integrated model of climate and economy with GDP spillovers) model, which is an IAM but extends to include GDP spillover mechanism, to make assessment on several strategies for global emission reduction, including the egalitarianism strategy, the UNDP strategy and the Copenhagen Accord. Using 1990 as a baseline for historical emission levels, the egalitarian strategy argues that developed countries should implement urgent emission reductions, whereas developing countries are allowed relatively higher future emission quotas. The UNDP strategy addresses the issue of substantial changes in global temperature but acknowledges that developing countries are not able to afford more costs for mitigation measures, which is inequitable from the perspective of a country’s right to develop. We also simulated the Copenhagen Accord to determine the consequences by the year 2100 if each country continues their current emission mitigation actions, and results indicated that the increase in global temperature will be 2.8℃ by 2100; consequently, much stronger emission reduction efforts must be implemented after 2020. Based on analysis on mitigation strategies, it is recognized that the common but differentiated responsibility principle must be insisted when making global mitigation strategy. To comply with this principle, the emission reduction baseline of developed and developing countries should be discriminated, so 1990 and 2005 can be taken as the base year for developed and developing countries respectively.

  • Human-Environment Interactions
    WEI Dongying, James WILSON, Lloyd RICHARDSON, Carole MURPHY, WANG Min, LIU Changming
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    From 27th to 29th, May, 2011, the participants of the 2nd International Forum on Geoparks from 5 countries gathered in Taining, Fujian Province, China. The participants discussed developing and preserving our Geoparks and Geo-heritage in sustainable ways. The forum recognized that the Geopark Program initiated by UNESCO is an efficient tool for geo-heritage protection, recreation, education and economic development. The role of capacity building in achieving sustainable development of Geoparks is significant and the potential for capacity building has not been fully realized.

  • Academic Information
  • Academic Information
    2012, 22(6): 1151-1151.
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    The 32nd International Geographical Congress (IGC) was held on August 26-30 in Cologne, Germany. About 3000 geographers from countries and regions across the world participated in the IGC, which caused an unprecedented number of attendees in the history of IGU. Organized by The Geographical Society of China (GSC), China had a record over 100 geographers to this congress, including Academician Qin Dahe, Vice President of IGU, and Academician Liu Changming, former Vice President of IGU.