EN中文

Archive

  • Select all
    |
    Original Articles
  • Original Articles
    Characteristics of Holocene Temperature Change in China
    HOU Guangliang, FANG Xiuqi
    2011, 30(9): 1075-1080. https://doi.org/10.11820/dlkxjz.2011.09.001
    Download PDF ( )   Knowledge map   Save
    Based on the researches on temperature change in China in the Holocene, the characteristics of temperature variability were displayed in this report. The temperature variation in the Holocene could be divided into three stages: ascending in the early Holocene with great fluctuations, Megathermal in the mid-Holocene, and descending in the late Holocene. The temperature in the warmest period of 8.0-6.2 kaBP was 1℃ higher than at present. Ten cold intervals which occurred in 11.0 kaBP, 9.8 kaBP, 9.2 kaBP, 8.9 kaBP, 8.2 kaBP, 6.2 kaBP, 4.0 kaBP, 2.8 kaBP, 1.5 kaBP and 0.4 kaBP were consistent with the eight cold events in the North Atlantic domain. It seems that the most significant cold-events appeared in 4.0 kaBP and 0.4 kaBP. Warm events occurred around 8.6 kaBP, 4.7 kaBP and 3.5 kaBP. The significant periodicities of temperature variation in the Holocene were 1000a and 700a.
  • Original Articles
    Study on Holocene Paleoflood in Malian River Basin
    ZHOU Fang, ZHA Xiaochun, HUANG Chunchang, WANG Xiaqing, SANG Jingjing
    2011, 30(9): 1081-1087. https://doi.org/10.11820/dlkxjz.2011.09.002
    Download PDF ( )   Knowledge map   Save
    Through investigations in the middle and lower reaches of Malian River, Holocene palaeoflood slackwater deposition profile were identified in Heshui County. Samples of the palaeoflood slackwater deposits were collected, and the grain-size distribution and the quartz grain surface texture were examined. All of these indexes showed that the slackwater deposits were typical in the study area. Stratigraphic correlations showed that the slackwater deposits recorded the largest floods occurred between 4200-4000 a B.P. on the river. The flood peak discharges were estimated to be 16780-17200 m3/s by using the slope-area method. Reconstruction of the peak discharge of the 2003 and 2005 floods with the same method and indicators showed that the palaeoflood reconstruction was reliable. These results are important for hydraulic engineering and flood control along the Malian River.
  • Original Articles
    Review on Adaptation in the Perspective of Global Change
    CUI Shenghui, LI Xuanqi, LI YANG, LI Fangyi, HUANG Jing
    2011, 30(9): 1088-1098. https://doi.org/10.11820/dlkxjz.2011.09.003
    Download PDF ( )   Knowledge map   Save
    The study on adaptation attracts much attention in the field of global change. Based on the concepts of adaptation, this paper concluded scientific meanings of adaptation and the approaches to study adaptation. As listed below, there are three approaches to study adaption: (1) in the perspective of sensitivity-vulnerability-adaptation, (2) in the perspective of adaptive capacity-resilience-vulnerability, and (3) in the perspective of of resilience- vulnerability-adaptation. Furthermore, this paper also discussed how to take the study of adaptation into practice and provided several examples. Finally, the aim and focal points of the study on adaption were discussed in this paper.
  • Original Articles
    Advances in the Indicator of Palaeowind Direction Reconstruction
    LIU Li'an, JIANG Zaixing
    2011, 30(9): 1099-1106. https://doi.org/10.11820/dlkxjz.2011.09.004
    Download PDF ( )   Knowledge map   Save
    The reconstruction of palaeowind direction has been a major concern in the study of palaeo-atmospheric circulation. The present geological indicators for the reconstruction of palaeowind direction include aeolian landform, spatial distribution of aeolian sediments and results of wind force. This paper summarizes the present geological indicators in the study of palaeowind direction, including direct indicators, indirect indicators and other indicators. Time perspective shows that for the period after the Quaternary, there have been more indicators and diverse reconstruction methods while for the period before the Quaternary, less indicators have been observed but widely applied. Space perspective indicates that the indicators can be easily obtained in arid climatic zones, while the indicators in humid climatic zones are relatively rare and the scope of application is limited. Searching for more indicators is a burning issue in the study of reconstructing palaeowind direction.
  • Original Articles
    Progress in Monitoring Wetland Ecosystems by Radar Remote Sensing
    WANG Liwen, WEI Yaxing
    2011, 30(9): 1107-1117. https://doi.org/10.11820/dlkxjz.2011.09.005
    Download PDF ( )   Knowledge map   Save
    Wetlands is important ecosystems with high productivity and abundant biology diversity. Wetlands have high resource values, economic values, environmental values and a variety of ecological functions. Wetlands research has become a highlighted domain that associates with geography, environment and ecology. The earliest article about wetlands monitoring by radar remote sensing appeared around 1970. Afterwards, many satellites radar sensors were launched, such as SEASAT, ERS, JERS-1, Radarsat, Envisat, ALOS and TerraSAR-X; many space shuttle radar sensors were used, such as SIR-A, SIR-B, SIR-C/X-SAR and SRTM; many airplane sensors were applied, such as AIRSAR, EMISAR and E-SAR. Researchers have published a lot of papers about wetlands and radar data.
    Monitoring wetlands by radar remote sensing have undergone for 20-30 years and yielded many achievements. But a great number of problems for complicated wetlands still need to be further researched. In this paper, main radar parameters including wave length, polarization, and incident angle were discussed, and involved issues such as temporal and environmental effects and analysis technologies were reviewed. Research conclusions published in geographical literatures and development trends were also analyzed.
    The latest literature shows that multi-dimension radar dataset has been used for wetlands location determination, area estimation, and environmental condition analysis. Wetlands mapping based on radar data is not limited in research. This trend can speed up the use of radar data, and expand the application diversity. It has been a programmed process for flooding region mapping from radar data. Radar data in environment monitoring have become accepted tools in the studies such as epidemic region mapping, rangeland management and pollution prevention.
    Radar remote sensing plays an important role in protecting fragile wetlands environment. Under any weather conditions, radar system can provide high resolution observation data, so it has become a special earth resource monitoring technology. In addition, radar remote sensing can provide land cover type information and underground physical characteristics that cannot be detected by other spectral bands. With the development of multi-bands, multi-polarization, and multi-angle radar remote sensing system, its information value will be continuously boosted.
  • Original Articles
    Spatial Scale Analysis of the Methods Using U-TAE Algorithm to Extract the Information of Urban Heat Island
    LIU Yupeng, YANG Bo, CHEN Chong
    2011, 30(9): 1118-1124. https://doi.org/10.11820/dlkxjz.2011.09.006
    Download PDF ( )   Knowledge map   Save
    U-TAE is an algorithm which uses moving windows of different areas to extract the information of UHI and sets each moving window's threshold according to robust estimation method. This algorithm distinguishes non-UHI area and UHI area according to the cumulative times in which pixels have thermal anomalies and determines the intensity of UHI according to the cumulative times with high or low values. It has dynamic threshold and unbiased characteristics. The U-TAE algorithm is used to evaluate its performance in six different scales: 5×5, 11×11, 25×25, 51×51, 101×101 and 201×201. The performance evaluation includes four aspects: area, intensity, space structure of UHI and stability of large-scale UHI. The results show that the best size of the moving window is 11×11. At this size the information of UHI is more complete and effective than at other sizes.
  • Original Articles
    Overview on the Estimation of Photosynthetically Active Radiation
    DONG Taifeng, MENG Jihua, WU Bingfang, Du Xin, NIU Liming
    2011, 30(9): 1125-1134. https://doi.org/10.11820/dlkxjz.2011.09.007
    Download PDF ( )   Knowledge map   Save
    PAR (Photo-synthetically Active Radiation) is an important field of the research on global change and terrestrial ecosystem, and is not only an important factor for measuring photosynthesis but also a driving factor of global change. This paper comprehensively reviewed the PAR estimation methods, and included the traditional methods and the remote sensing methods. The climatological and the parameter methods are the most common traditional methods, and the conversion factors and parameters methods based on remote sensing are developed from the traditional methods. The climatological method are a common method for estimating PAR, however, with the development of the study on ecosystems, the methods based on remote sensing become a new kind of methods, which can cover a wide range. Estimation of regional and global PAR by remote sensing becomes possible. How to produce long time series PAR is one of the current concerns around the world. Previous studies have showed that quantitative methods will be the main kind of estimation methods, such as the LUT method. It not only explains the mechanism of PAR in the transmission process, but also enhances the reliability, operability and universality of the estimation methods.
  • Original Articles
    The Fluctuation of the Cold Weather Disasters in Guangxi Based on Wavelet Theory
    YUWenjin, YAN Yonggang, HAO Ling, YU Hengxin, LI Fen
    2011, 30(9): 1135-1142. https://doi.org/10.11820/dlkxjz.2011.09.008
    Download PDF ( )   Knowledge map   Save
    Based on the analysis of the 52-year climatic data from four typical stations in Guangxi with the method of Morlet wavelet, the frequency features of the cold rainy weather in Guangxi have been investigated. The results show that (1) the average temperature between February and April in Guangxi increases gradually, the annual number of cold rainy days decreases gradually and the end dates of this kind of weather have become earlier; (2) the average temperature of Guangxi between February and April has the robust periods of 30 years, 18-19 years, 12 years and 3 years, and among them, the 30-year period is dominant. The annual number of cold rainy days has the robust periods of 30 years, 10 years and 2-5 years, but the dominant period is different meridionally with the value decreasing southward; (3) the robust period of the average temperature and the annual number of cold rainy days in Guangxi between February and April is consistent in the large-scale (30a) oscillations. These results show the advantage of the wavelet theory in the research on the frequency structure of the disaster weathers.
  • Original Articles
    Comparation of the Temperature Spatial Interpolation Methods Based on MODIS Data and Meteorological Observation Data
    ZHOU Tingting, CHENWenhui
    2011, 30(9): 1143-1151. https://doi.org/10.11820/dlkxjz.2011.09.009
    Download PDF ( )   Knowledge map   Save
    This study makes use of MODIS image data and the daily average temperature data from the 32 meteorological stations to reckon the surface temperature in Fuzhou, and by combining terrain factors extracted from the digital elevation model DEM to explore and study the correlations among the temperature, longitude, latitude, altitude and other factors, and establishes a model to interpolate the surface temperature in Fuzhou. Using meteorological data to interpolate surface temperature is faster, but the calculation is slightly higher than the actual value. Using image data to reckon land surface temperature is affected by the accuracy of parameters. When using correct parameters, the calculation of land surface temperature from the images has higher accuracy than the interpolation by the measured meteorological data. The parameters limit the accuracy of land surface temperature estimation, and the future research should focus on selection of parameters. Based on the topographic effects on temperature, we build a correlation model between topographical factors and temperature, and the accuracy is relatively high. In the future research, we will try to bring other factors such as the terrain, slope, aspect and slope position into the model to improve the accuracy.
  • Original Articles
    Offshore Hydrodynamic Calculation Based on GIS and FVCOM Numerical Model: A Case Study of Bohai Sea
    ZHAO Xiaodong, WANG Liang, SHEN Yongming
    2011, 30(9): 1152-1158. https://doi.org/10.11820/dlkxjz.2011.09.010
    Download PDF ( )   Knowledge map   Save
    GIS, with its powerful spatial data storage, processing and analysis functions, has been widely used in many engineering modelling and calculations. FVCOM model is an ideal model for offshore hydrodynamic calculations, providing a better adaptability in the coastal region with complex geometry and ensuring the conservation of momentum, mass, and energy in a unit volume. A case study of Bohai Sea was conducted based on GIS coupling with FVCOM model, which provided a pre-processing of spatial data management, automatic mesh generation and data extraction with a result of improving the efficiency of modeling, debugging and pre-processing. In the post-processing, the NetCDF and Geodatabase spatial database format were used to store multi-dimensional calculation data. The calculation results of the tide and salinity of the Bohai Sea were also verified and analyzed. The results of analyses show that the GIS coupled model can facilitate data handling and greatly improve the modelling efficiency with clear and vivid visualization of the results, reflecting the physical characteristics of the study area, and providing decision-making support of data and theory for coastal environmental management.
  • Original Articles
    Review of the Optimization Methods for Groundwater Monitoring Network
    GUO Yansha, WANG Jingfeng, YIN Xiulan
    2011, 30(9): 1159-1166. https://doi.org/10.11820/dlkxjz.2011.09.011
    Download PDF ( )   Knowledge map   Save
    The general goal of groundwater monitoring network optimization is to obtain more groundwater dynamic information with a certain precision using the least investment. A highly efficient monitoring network not only provides real-time dynamic information and reliable sources for scientific research in groundwater environment, but also helps policy-makers in making efficient decisions, and therefore a reasonable layout of groundwater monitoring network is of great importance. The optimization of groundwater monitoring network mainly includes network density, monitoring location, monitoring indicators and monitoring frequency. At present, a number of qualitative and quantitative methods have been used and many achievements have been made. These research work basically aimed at single objective optimization, and ignored the issues such as space-time analysis based on multi-objective and combined methods. The purpose for this paper is to analyze and compare the methods for optimizing the groundwater monitoring network, and then to propose a multi-objective optimization system in conbination of several methods.
  • Original Articles
    Progress in the Research and Application of Uncertainty Analysis Methods for Hydrological System
    WANG Yuli, WANG Xuan, YANG Zhifeng, TAN Yayi
    2011, 30(9): 1167-1172. https://doi.org/10.11820/dlkxjz.2011.09.012
    Download PDF ( )   Knowledge map   Save
    Hydrological system is a complex system with many uncertain factors. These factors are not conductive to the accurate simulation and prediction of hydrological processes. Thus more and more people focus on the uncertainty analysis methods for the hydrological systems to improve the reliability of calculations. In this paper, we summarized the researches and the applications of the uncertainty analysis methods for hydrological systems. Based on the review, we introduced their mathematical principles, operational procedures and status of applications. Furthermore, the key tasks in the future were put forward, including uncertainty analysis of the mechanism of hydrological circulation and hydrological processes in combination of various methods.
  • Original Articles
    Spatial Difference of Land Productivity and Its Influencing Factors in Hebei Province
    LI Yi, ZHU Huiyi
    2011, 30(9): 1173-1179. https://doi.org/10.11820/dlkxjz.2011.09.013
    Download PDF ( )   Knowledge map   Save
    Food security is an extremely important factor which affects the regional and national socio-economic stability and development. In the context of continuing reduction of cultivated area, the improvement of land productivity is a long term task for China's grain security, and that requires scientific understanding the spatio-temporal differences of land productivity and their influencing mechanism. This paper chooses Hebei Province as the study area which is one of the major grain producing areas, and 136 counties (cities) as the basic spatial units in the province, presents and analyzes spatial differences of land productivity, and then identifies the main influencing factors by using the methods of partial correlation analysis and principal component analysis. The results show that the current regional spatial difference of land productivity is not affected by a single factor, but is the result of several factors influencing together including factors such as terrain and production inputs, and the dominant factor is significantly different in regions at different levels. This is the scientific basis for improving land productivity in different regions.
  • Original Articles
    Dynamic Simulation of the Spatial Changes of Land Use in the Ha-Da-Qi Industrial Corridor
    ZHANG Lijuan, LIWenliang, LIU Dong, ZHOU Dongying, P.H.Verburg
    2011, 30(9): 1180-1186. https://doi.org/10.11820/dlkxjz.2011.09.014
    Download PDF ( )   Knowledge map   Save
    CLUE-S model is a spatial simulation model used in small-scale and high-resolution land use change simulation, in which raster data are directly expressed by the land use type. The area of the Ha-Da-Qi industrial corridor is 34510.44 km2, and is a large-scale study area. This paper simulates land use change in seven cities and counties of the Ha-Da-Qi industrial corridor based on Landsat TM remote sensing data of 1990, 2000 and 2005, splicing land use change simulation maps of each city and county. The study realizes the large-scale land use change simulation by using CLUE-S model. The research results can be drawn as follows. The major trend of land use change in the Ha-Da-Qi industrial corridor up to 2015 is that cultivated land will increase slightly by about 2.62%. Construction land will significantly increase by about 24.37%, and forest, grassland and water area will decrease by about 11.17%, 6.44% and 18.04% respectively. Unused land will decrease by about 5.58%.
  • Original Articles
    Changes of Intensive Urban Land Use and Its Causes in Eastern China during 2000-2007
    ZHOUWei, CAO Yingui, QIAO Luyin
    2011, 30(9): 1187-1192. https://doi.org/10.11820/dlkxjz.2011.09.015
    Download PDF ( )   Knowledge map   Save
    The contents of intensive urban land use are abundant and the concept of intensive urban land use is related to multi-aspects. The authors indicate that intensive urban land use is a kind of land use manner, which can improve urban social benefits, economic benefits and ecological benefits by increasing the per unit area input of construction land. This paper takes 87 cities as researching objects in order to construct an appraisal indicator system of intensive urban land use, to analyze changing rules of intensive urban land use during 2000-2007, and create multiple regression models between intensive use index values and impact factors, and to analyze the causes of intensive urban land use change. In the research, analytic hierarchy and multiple regression analyses are used. The results are obtained as follows. (1) Appraisal indicator systems should be established by considering population carrying amount, economic input and economic output, and economic output is the most important influencing factor for intensive urban land use; (2) Changing trends of intensive urban land use average index values in Beijing is the highest, and the changing trends of the other 9 provinces are similar. Standard deviation of the average index values in Guangdong is the biggest, and the fluctuation of standard deviation of the average values is the largest. (3) Most intensive urban land use index values are in a range of 0.1000-0.2000. (4) The multiple regression between the intensity index values and some indicators is negative in some urban areas.
  • Original Articles
    Progress and Prospect of the Research on Transfer of the Collectively Owned Rural Construction Land
    WEN Feng, LU Chunyang, YANG Qingyuan, ZHOU Guifang, WANG Cheng
    2011, 30(9): 1193-1200. https://doi.org/10.11820/dlkxjz.2011.09.016
    Download PDF ( )   Knowledge map   Save
    The transfer of collectively owned rural construction land which is necessary for rational distribution and optimal allocation of production factors under the market economy system, and is also an important measure to improve efficiency and benefits of land use. In this article, the deficiency of the current research in the aspects of feasibility, motivation, present situation, patterns, subjects, circulation systems and supporting systems about the transfer of collectively owned rural construction land are concluded, which may provide references for the future research in this area to help make the policy for balanced urban and rural development. Five research aspects about the transfer of collectively owned rural construction land should be enhanced. (1) Research on calculating methods of transfer potentiality of the collectively owned rural construction land should be improved. (2) Research on the price in the transfer of collectively owned rural construction land should be deepened. It is necessary to enhance the study on price estimating method which is a theoretical basis for price making. (3) Research on profit distribution in the transfer of lands should be strengthened. (4) Risk control in the transfer of collectively owned rural construction land should be emphasized. (5) Quantitative study on the transferring potentiality and driving forces should be reinforced, which can provide more acurate data for decision-making.