Table of Content

    25 July 2011, Volume 30 Issue 7 Previous Issue    Next Issue
    Original Articles
    Conceptual Framework of Carbon Sequestration Rate and Potential Increment of Carbon Sink of Regional Terrestrial Ecosystem and Scientific Basis for Quantitative Carbon Authentification
    YU Guirui, WANG Qiufeng, LIU Yingchun, LIU Yinghui
    2011, 30 (7):  771-787.  doi: 10.11820/dlkxjz.2011.07.001
    Abstract ( 665 )   PDF (969KB) ( 1328 )   Save
    It is not only an urgent need for mitigating global climate change to study the carbon sequestration rate, potential increment of carbon sink of regional terrestrial ecosystem and its quantitative authentification, but also the core task of carbon cycle research in earth system, and the scientific foundation of terrestrial ecosystem management. In the past two decades, vast research have been done at home and abroad, and a lot of feasible techniques for increasing carbon sink have been developed in the practice of carbon management. Meanwhile, many concepts of carbon sequestration rate and potential increment of carbon sink of terrestrial ecosystem, and methods for carbon accounting and authentification have been put forward based on different demands and subjects. Due to lacking systematic and sufficient discussion, large discrepancy exists in the understanding of related concepts among different sections and subjects, which leads to the concept confusion and the difficulty in the standardization of accounting methods. In this paper, related concepts such as carbon storage, carbon sequestration rate, and carbon sequestration potential of ecosystem were expounded systematically based on the basic concept of carbon sequestration of terrestrial ecosystem; practical potential of carbon sequestration, socioeconomic potential of carbon sequestration, technical potential of carbon sequestration, theoretical potential of carbon sequestration, and the potential of carbon sequestration ratified by Kyoto Protocol were analyzed based on the realizability of the techniques for increasing carbon sink; and the scientific foundation, limitation and uncertainty of different methods for authenticating, analyzing, and assessing carobn sink, such as time continuous inventory method, space for time reference method, and limited factor analysis method as well, were expatiated finally. The final goal of this paper is to arouse the attention of academe and related sections, to promote the standardization in quantitative authentification of carbon sink, and to provide foundation for establishing methodology and technique system for accounting, reporting, authentificating, and checking of carbon sink in China.
    References | Related Articles | Metrics
    The Approaches to Enhance Carbon Sequestration of Terrestrial Ecosystem at Regional Scales, and Their Feasibility
    HE Nianpeng, WANG Qiufeng, LIU Yinghui, RENWei, YU Guirui
    2011, 30 (7):  788-794.  doi: 10.11820/dlkxjz.2011.07.002
    Abstract ( 409 )   PDF (725KB) ( 709 )   Save
    What are the optimizing artificial managements to enhance carbon (C) sequestration of terrestrial ecosystems at regional scales, and how to evaluate them, are of concern for ecologists, environmental experts, and government officials. In this study, we first discussed the approaches to enhance C sequestration by natural processes and human activity, respectively. Based on an expert assessment system, we then evaluated qualitatively the effect of C sequestration of various artificial managements, which had been utilizing widely in forest, grassland, farmland, and wetland ecosystems in China. We found that most of artificial managements have apparent capacity to enhance C sequestration of terrestrial ecosystems, and are feasible in view of technology and economy. Base on our qualitatively evaluation, we proposed 2 or 3 artificial managements for forest, grassland, farmland and wetland ecosystems, respectively, which have evident potential to enhance C sequestration and are easy to be extended. Furthermore, we found that some artificial managements mentioned above have not been adopted in 2006 IPCC guidelines for national greenhouse gas inventories. In order to put forward scientific foundation and finally promote these artificial managements accepted by IPCC, scientists therefore should select these excellent managements for terrestrial ecosystems in China to investigate systematically the processes of C cycle and C sequestration, and to develop new methods for the evaluation of C sequestration in terrestrial ecosystems.
    References | Related Articles | Metrics
    Certified Carbon Inventory Methods of Carbon Sequestration Rate and Potential in Terrestrial Ecosystem at Region Scale and Their Uncertainty Analysis
    RENWei, WANG Qiufeng, LIU Yinghui, HE Nianpeng, LIU Yingchun, FU Chao, YU Guirui
    2011, 30 (7):  795-804.  doi: 10.11820/dlkxjz.2011.07.003
    Abstract ( 563 )   PDF (547KB) ( 623 )   Save
    Carbon inventory certified methods of carbon sequestration rate and potential in terrestrial ecosystem at region scale and their uncertainty analysis are the scientific foundational work of taking practices to mitigating the global warming potential. A large number of studies have been carried out on the measuring methods of the terrestrial ecosystem carbon sink and the carbon sequestrating potential ,and the national greenhouse gas inventory methods, CDM (Clean Development Mechanism projects) afforestation and reforestation project methods, carbon inventory method in land-use and land-cover change and some other methods were proposed. National greenhouse gas inventory was applicable to state-wide measurement of carbon sequestration, and was not suitable for regional carbon inventory. CDM afforestation and reforestation project focused on the carbon sequestration potential of forest management, and did not take the practices of increasing carbon sinks carried on other ecosystems into account. To date carbon sequestration measurement for forest, grassland, farmland and other regional- scale of ecosystems do not have a uniform and standardized methodology yet. In this paper, we first introduced national greenhouse gas inventory methods, CDM afforestation and reforestation project methods, carbon inventory method in land-use and land-cover change and analysis their uncertainty in detail. Then we proposed a carbon inventory method applicable to farmland, grassland, forests and other terrestrial ecosystems, aiming to provide scientific basis for establishing the methodology for measuring, reporting, and verifying the carbon sequestration rate and potential in regional terrestrial ecosystems.
    References | Related Articles | Metrics
    Improved Priestley-Taylor Method and Its Application in Complementary Relationship Evapotranspiration Model
    ZHAO Lingling, WANG Zhonggen, XIA Jun, CHEN Xi, QIN Nianxiu
    2011, 30 (7):  805-810.  doi: 10.11820/dlkxjz.2011.07.004
    Abstract ( 949 )   PDF (882KB) ( 892 )   Save
    Priestley-Taylor method is developed under the condition of non advection water vapour transport, however, this assumption is hardly satisfied in reality. Some researches introduced the parameter in order to eliminate the error brought by the non-advection assumption. According to many researches, the value of parameter has some uncertainty. This paper tries to introduce an advection coefficient to reflect the influence of advection on evaporation. The case analyses suggest that this method could provide the minimum energy for calculating evaporation in winter. Compared with the original formula, the calculation accuracy of evaporation has been effectively improved, especially in winter and summer.
    References | Related Articles | Metrics
    Study on Spatial Interpolation of Precipitation with Large Scale Samples: A Case Study on 2009’s Precipitation of China
    ZENG Hongwei, LI Lijuan, ZHANG Yongxuan, LIU Yumei
    2011, 30 (7):  811-818.  doi: 10.11820/dlkxjz.2011.07.005
    Abstract ( 606 )   PDF (981KB) ( 806 )   Save
    This paper studies spatial interpolation of precipitation at a national scale, the precipitation data comes from 2203 meteorological stations of China in 2009. The research content includes three parts as follows. At first, this paper divided the stations into different groups by stochastic methods, including 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10%, 5% and 4% sampling rate groups, and analyzed the impact of sampling data on interpolation result by inverse distances weighting methods. Secondly, the stations with 80%, 50% and 20% of sampling rates were treated by the same sampling interval method, which extracted sampling data with gaps equal 1 or 4 according to ID serial number. By comparing interpolation result with the result by stochastic method in the same sampling rate, this paper analyzed the relationship between sampling methods of data and the result of interpolation. Finally, the paper analyzed the differences of interpolation result by IDW, Kriging and Co-Kriging in the same sampling rate groups. We can draw some conclusions as follows: (1) Using IDW methods, MAE and RMSE decreased gradually as the amount of sampling data increased, while the correlation coefficient decreased at the same time. The increase from 50% to 90% was slow with slight fluctuations, and that from 20% to 50% became obvious. Especially, when the sampling fraction <20%, MAE and RMSE were increased significantly, and the correlation coefficient was significantly reduced. (2) We found that the relationship between uniform of stations distribution and precipitation interpolation results was complex after cross-validation, and sometimes it did not have better interpolation result under more uniform distribution of stations. (3) With not only the random sampling data, but also the same interval sampling data, MAE and RMSE using IDW methods were large than Kriging interpolation method, while R2 was smaller. It is suggested that Kriging interpolation was better than IDW method in this paper. Taking 50% and 20% sampling rate groups as an example, using IDW and Kriging spatial interpolation methods, we obtained the precipitation spatial distribution of China, and the interpolation results were consistent with the actual situation.
    References | Related Articles | Metrics
    Reconstruction of MODIS LST Time Series and Comparison with Land Surface Temperature (T) among Observation Stations in the Northeast Qinghai-Tibet Plateau
    KE Linghong, WANG Zhengxing, SONG Chunqiao, LU Zhenquan
    2011, 30 (7):  819-826.  doi: 10.11820/dlkxjz.2011.07.006
    Abstract ( 784 )   PDF (1108KB) ( 1373 )   Save
    Land surface temperature (RS-LST) derived from remotely sensed data is a good alternative because traditional LST data from meteorological stations have limitations in terms of locality, accessbility and cost. Yet MODIS standard LST products from NASA may suffer from noises from various sources including‘cloud contamination’, which greatly degrade the LST quality and hamper its efficient applications. The paper presents a novel algorithm which can reconstruct complete LST image based on regression analysis of LST with elevation in each sliding window of the original image, after filtering low-quality and unreliable pixels with Quality Asessment (QA) information and Histogram Outliers Removing method. Terra/Aqua MODIS-LST with overall four temperature channels in the northeast Qinghai-Tibet Plateau in 2008 are reconstructed using this method. Comparison of reconstructed 8-day composite LST data with corresponding landsurface temperature (T) observations from eleven meteorological stations in the study region indicates that LST is significantly correlated with T with an average correlation coefficient of 0.96 and a mean abosolute difference (MAE) of 2.02℃. When aggregated to monthly serials and yearly serials, LSTs and Ts show no significant differences in Paired-T-Test (with MAE of 1.55℃ and 0.60℃, respectively). The differences between LSTs and Ts have certain correlations with their different spatial and temporal definations; however some residual noises existing in the reconstructed LSTs indicate more meticulous algorithem needed to work out more accurate RS-LST data.
    References | Related Articles | Metrics
    Characteristics of Ground Temperatures and Influencing Factors of Permafrost Development and Distribution in the Source Region of Datong River
    LI Jing, SHENG Yu, CHEN Ji, ZHANG Bo, WU Jichun, ZHANG Xiumin
    2011, 30 (7):  827-836.  doi: 10.11820/dlkxjz.2011.07.007
    Abstract ( 533 )   PDF (1346KB) ( 559 )   Save
    Permafrost is thermally defined as the ground where temperatures have remained at or below 0℃ for a period of at least two consecutive years. Ground temperatures at depth were a valid index to make knowledge of permafrost thermal regimes and permafrost development at certain locations. Based on 39 borehole data, drilled in the summers of 2007 and 2009 at different elevations with representatives of surface characteristics of topography, geomorphology, landcover, vegetation and soil water content, and the measured ground temperatures in the source region of Datong River in the northeast Qilian Mountains, the characteristics of ground temperatures at depth at the drilling sites were analyzed using the temperature profiles, and the main factors controlling permafrost temperatures and distribution in the study area were primarily summarized. Elevation and the elevation- dependant MAAT (mean annual air temperature) determined the climate settings of the region and the macro-scale permafrost distribution and temperatures patterns, and thus were the first-order factors affecting permafrost temperatures in the source region. In the local- or micro-scale areas in low- and mid-elevation zones (elevation generally lower than 3800 m), however, the landcover conditions (vegetated area, bare ground or exposed rock), the vegetation type (the alpine meadow or the swampy alpine meadow), and the topsoil water content (saturation or oversaturation) had some important impacts on permafrost temperatures, which could affect the permafrost occurrence at certain locations and lead to the spatial differentiation of permafrost distribution. In high-elevation zones (elevation usually exceeds 4000 m), elevation alone could determine the presence of permafrost, and the local factors had effects on the gradient of permafrost temperatures with depth. The result could be as the basis of understanding the permafrost stability, and permafrost change or degradation under the climatic warming, also could provide the knowledge to the relevant studies of climatic changes, ecology, and hydrology in cold regions.
    References | Related Articles | Metrics
    The Temporal and Spatial Distributions and Circulation Features of High Temperature Days during last 50 years in Shanxi
    MIAO Aimei, JIA Lidong, LI Miao, FAN Guanghai
    2011, 30 (7):  837-845.  doi: 10.11820/dlkxjz.2011.07.008
    Abstract ( 514 )   PDF (1164KB) ( 509 )   Save
    With the high-low air meteorological observational data, the original meteorological record, monthly report and meteorological information of 109 stations during 1958-2008 archived by Shanxi Meteorological Information Center, taking the highest temperatures of ≥35℃, ≥37℃ and ≥40℃ as indexes, this paper studies the temporal and spatial distributions, changing trend and circulation features of high temperature days in Shanxi. The results are shown as follows. (1) The earliest high temperature day appears in mid-April in Shanxi, and the latest appears in mid- September, the days with high temperatures of ≥35℃, ≥37℃ and ≥40℃ are in late June. (2) The high temperature days decrease with the increase of latitude and sea level elevation. The areas with high temperatures of ≥40℃ are mostly centralized in Yuncheng and Linfen. (3) The high temperature days of ≥35℃ show a rising trend during 1984-2008. During the 31-year period from 1979 to 2008, the high temperature station frequencies are increased 153 times per 10a. After entering the 1990s, not only the high temperature days, but also the duration, strength, range of the high temperature are increased. (4) There are three types of 500 hPa circulation patterns which can influence Shanxi high temperature: zonal type of the horse latitude high, meridional type of the horse latitude high, and controlling type of continental pressure ridge. Under some special flow pattern configurations, T850≥25℃, T700≥13℃, T850≥26℃, T700≥14℃, T850≥28℃, T700≥15℃, T850≥32℃ and T700≥16℃ are critical values for ≥35℃, ≥37℃ and ≥40℃ high temperature weather forecasts under the influence of wind directions in different regions in Shanxi.
    References | Related Articles | Metrics
    The Response to Holocene Climatic Events of Shandong and Their Impacts on Human Activity
    CHEN Dongdong, PENG Shuzhen, ZHANG Wei, HAN Junqing, DING Min
    2011, 30 (7):  846-852.  doi: 10.11820/dlkxjz.2011.07.009
    Abstract ( 531 )   PDF (674KB) ( 1348 )   Save
    There were several climatic events in the Holocene, and the 8.2 ka BP, 5.5 ka BP and 4.0 ka BP events were significant ones of them. Based on the synthesis of the published Holocene climatic records and present archaeological materials, we find that these significant Holocene events show different climatic patterns and have different impact on the human activity in Shandong Province. Both the 8.2 ka BP and 5.5 ka BP events in this area have cold and dry climatic features. The former produced Houli Culture and the latter promoted the development of Dawenkou Culture. Flood and the following cold-dry climate featured the 4.0 ka BP event, and led to the collapse of Longshan Culture in Shandong Province.
    References | Related Articles | Metrics
    Comparison Analysis of Water Quality between Yili River and Xitiaoxi River in Taihu Basin
    WANG Yichen, YAO Zhijun, LIU Zhaofei, KANG Huimin
    2011, 30 (7):  853-860.  doi: 10.11820/dlkxjz.2011.07.010
    Abstract ( 791 )   PDF (726KB) ( 981 )   Save
    Principal pollutants in the waters were compared between Yili River and Xitiaoxi River located in the west and southwest of Taihu basin, based on field observations at various sampling sites in July and November in 2010. Several factors which might induce the pollutants in these inflows were also analyzed related with the socio-economic, geographical and other aspects in the Taihu basin. Several indicators were selected in this study, including chemical oxygen demand (CODMn), total phosphorus (TP), total nitrogen (TN) and ammonia-N (NH3-N). Field observations were carried out at 22 river sections and all selected indicators were monitored. Results show that CODMn, TN, NH3-N and TP of Yili River in non flood season were significantly higher than that in flood season. Water quality of Xitiaoxi River in flood period was worse than that in non flood season. Water quality of Yili River is worse than that of Xitiaoxi River. Because of the spatial distribution of urban areas, population, industrial pollution and other business factors, the spatial variation of water quality of both rivers is very obvious. Yili River is mainly polluted by point source pollution. While the downstream of the river is also affected by non-point source pollution in the flood period. Water pollution of Xitiaoxi River mainly comes from non-point source pollution, which is caused by rainfall and runoff carrying most of the pollutants into Xitiaoxi River in flood season.The pollution of the downstream of Xitiaoxi River is also affected by emissions from point sources.
    References | Related Articles | Metrics
    Analysis of Runoff Characteristics of Luanhe River under Various Emission Scenarios in the Next Century
    XIANG Liang, LIU Xuefeng, HAO Lisheng, ZHAI Jianqing, SHI Yinshan
    2011, 30 (7):  861-867.  doi: 10.11820/dlkxjz.2011.07.011
    Abstract ( 572 )   PDF (944KB) ( 554 )   Save
    Based on the ECHAM5/MPI-OM mode, using the climate change forecast actual experimental data for the next century under three scenarios (A2 high emission, A1B emissions, B1 low emission ), this paper applied HBV model to study the future of the Luanhe River Basin (2010-2100) under different scenarios of climate and runoff change. The result showed that HBV model had good practicability in the Luanhe River Basin. Using HBV model and predicted climate change data of the three emissions scenarios for the next century from the ECHAM5/MPI-OM model, it is found that in the three emission scenarios, the average runoff depth of Luanhe River Basin will have little change in the next century, but the trends will be quite different and the annual variation will be prominent. Overall, the depth of runoff in the Luanhe River basin will have varying degrees of increasing trend in the next century under the three scenarios, and it will have a significant increasing trend in scenario B1. There is a period of 2-9 years in scenarios A2 and A1B, while periodic change is not obvious in scenario B1.
    References | Related Articles | Metrics
    Characteristics of Different Water Bodies in Summer over Yulong Snow Mountain Area
    ZHU Guofeng, HE Yuanqing, PU Tao, WANG Shuxin, XIN Huijuan, WANG Chunfeng
    2011, 30 (7):  868-874.  doi: 10.11820/dlkxjz.2011.07.012
    Abstract ( 489 )   PDF (1187KB) ( 543 )   Save
    Different water samples were collected in the Yulong Snow Mountain in Lijiang city, Yunnan Province on July 22-28, 2005. On the basis of description of the internal relations of different water bodies, characteristics of inorganic ions were analyzed to study the interaction mechanism of human-geosphere-atmosphere-hydrosphere in the study area. The results showed that there were obvious differences of inorganic ions in these water samples. Lake water and groundwater at low altitudes have larger concentration of inorganic ions and the glacier tongue melting water and melt water runoff at high altitudes have lower concentration. The major inorganic ions are HCO3-, Ca2+, Mg2+, SO42-, Na+, K+ and Cl-. As the first advantageous cations, Ca2+ occupied 53.27% of all the cations. In addition, HCO3- is the first advantageous anion,accounting for 70.35% of the total anions. The aggregate shortage is displayed by the low proportion of the aggregate of the other ions. The concentration of inorganic ions at an altitude higher than 4270 m showed high level under the influence of regional lithology. Due to sedimentation of melt water and non-fully dissolution of the ions from local lithology, low level was observed at an altitude of 4270-3180 m. At 3046-2400 m, HCO3-, Mg2+, Ca2+, K+ and Na+ showed high level under the influence of dissolve solids. NO3-, SO42- and K+ showed high level due to moisture transport and human activities. Compared with cations, there is more comparability in source, existence and reaction mechanism of anions. SO42-, K+, Na+, Mg2+ and Ca2+ in water mainly come from soil. Meanwhile, SO42- has a favorable enhanced effect on water-rock interaction. Moreover, Mg2+ and Ca2+ in water have the same source.
    References | Related Articles | Metrics
    Spatial and Temporal Distributions and Types of Impacts of Earthquake Disasters on Transportation from 1831 BC to 1980 AD in China
    REN Huizi, CAO Xiaoshu
    2011, 30 (7):  875-882.  doi: 10.11820/dlkxjz.2011.07.013
    Abstract ( 586 )   PDF (782KB) ( 690 )   Save
    Earthquake disasters have significant effects on traffic. With the development of economy and technology, the ability of people to deal with natural disasters is gradually enhanced. The vulnerability of the transportation system after earthquake disasters and the“lifeline”role that transportation system plays prompt people to pay more attention to the impacts of earthquake disasters on traffic. The research on earthquake disasters and traffic and other related issues are concentrated in earthquake engineering fields, namely from the perspective of traffic engineering construction to study the earthquake resistant behavior of the traffic system. There are relatively few studies from the perspective of human geography on the impacts of earthquake disasters on traffic based on the historical earthquake data. China has more detailed historical earthquake materials and data than any other countries in the world. China has not only a great deal of historical earthquake data, but also a large number of modern earthquake assembly data. On the basis of comprehensively coordinating the earthquake disaster data from 1831 BC to 1980 AD, and using the GIS technology, this article discusses the characteristics of China's earthquake disasters in time and space, and their influences. The earthquakes in China are imbalanced in spatial and temporal distributions. In the Yuan Dynasty, the earthquakes were concentrated in Shanxi, Henan and Shaanxi. Earthquakes in Southwest China and Taiwan increased in the Ming and Qing dynasties, and those in the Republic of China and during 1949-1980 occurred mainly in Southwest China, Northwest China and Taiwan. Traffic impacts by earthquake disasters were also concentrated in Northwest and Southwest China, especially in Yunnan, Sichuan and Xinjiang. The earthquakes with high intensities had significant influences on the transportation system of Xinjiang. And in Sichuan and Yunnan provinces, the earthquakes with low intensity also had great influences on the transportation systems. That is because the three are all in the pleistoseismic zone, and Yunnan and Sichuan provinces have complex geographical environments with more mountains. Different types of impacts can be divided according to the extent of damage, secondary disasters and ruin of transportation structures.
    References | Related Articles | Metrics
    Drought Risk Assessment on Regional Agriculture: A Case in Southwest China
    XU Xinchuang, ZHENG Jingyun, GE Quansheng, DAI Erfu, LIU Chengwu
    2011, 30 (7):  883-890.  doi: 10.11820/dlkxjz.2011.07.014
    Abstract ( 548 )   PDF (774KB) ( 757 )   Save
    Agro-drought risk assessment is helpful for improving ability of regional disaster management and mitigating the drought-induced loss. We used historic precipitation, disaster loss and socio-economical data in China as the basic data. The assessment was performed for the three crops with the biggest sown areas in each of prefecture-level region. By using the consecutive rainless days to scale the drought severity, we developed different standards of indexes to judge drought severities. The standards were relying on seasons, crop types and crop growth stages. Moreover, we developed a model for each type of crops. This model could be used to calculate risk loss under different severities of drought. In the next step, we integrated risk loss of each type of crops to assess the regional drought-induced agricultural loss, by weighting average approach. Using the above method we took Southwest China as a case area to assess its spatial distribution of agro-drought risk. We found that (1) from the results tested by historical loss of agro-drought hazards in recent 10 years (1997-2006) in Southwest China, the risk loss calculated by the model can reveal the loss differences between assessment units; (2) different risk regions divided by the composite risk index can well reflect the differences of spatial distribution in Southwest China; (3) high and extreme risk areas of agro-drought were primarily in the plateaus and mountains in the western and northern parts of the region, and slight and moderate risk levels were observed in the eastern, central and southern parts of Southwest China.
    References | Related Articles | Metrics
    Review of Drought Disaster Evaluation
    LI Fen, YUWenjin, ZHANG Jianxin , ZHU Fengqin, LIU Yingli
    2011, 30 (7):  891-898.  doi: 10.11820/dlkxjz.2011.07.015
    Abstract ( 787 )   PDF (435KB) ( 1111 )   Save
    Drought is a disaster which arises most frequently in the broadest area and has the most severe impact among natural disasters. In recent years,because the loss from natural disasters increased obviously,governments have paid more and more attention to the mitigation works. Scientists have begun to evaluate the impacts of natural disasters, including drought. This paper aims to grasp the actual situation of drought evaluating study and promote its further deepening. The research progress at home and abroad about drought from index,evaluating theory,evaluating methods and evaluating types is summarized. It is found from analysis that now-existing drought evaluating study mainly focuses on agricultural drought and single crop variety drought, lacking the simulation study of drought impact on ecological environment and social economy from a system point of view, and the drought evaluating models can not simulate the systematic impact of drought. It is suggested that future drought evaluating study should use more new techniques and methods and advance to the direction of multidisciplinary and comprehensive study.
    References | Related Articles | Metrics
    Study on the Distribution and Risk Zoning of Strong Winds in Heilongjiang Province
    ZHANG Lijuan, CHEN Hong, GAO Yuhong, MAYanmin, MAJun
    2011, 30 (7):  899-905.  doi: 10.11820/dlkxjz.2011.07.016
    Abstract ( 672 )   PDF (652KB) ( 532 )   Save
    This paper calculates the risk probability of strong wind by information diffusion theory, draws the risk zoning map by GIS technology, and then analyses the temporal and spatial distribution of strong winds in 78 counties or cities of Heilongjiang Province during 1971-2005. The results are shown as follows. (1) There were fluctuations of strong wind occurrence in Heilongjiang in the 1970s and 1980s. The occurrence of strong winds has been decreased noticeably from the 1990s to the early 21st century. Strong winds occurred mostly in spring, which was the main reason having drought and fire risks. (2) The high values of the number of strong wind days were mainly observed in Songnen plain and Sanjiang plain, and the low values appeared in Da Hinggan, Yichun and Mudanjiang. (3) The strong wind risk probabilities of 1d, 2d, 3d and 4d have been calculated by information diffusion theory. The areas with high risks were distributed in the central-southern parts of Heilongjiang as a zone from west to east, and those with low values were located in the northern, central-northern, western and southern parts. This paper takes the advantages of information diffusion theory, which requires less information and can evaluate the risks and loss risks.
    References | Related Articles | Metrics
    Landscape Ecological Planning and Design of Land Consolidation in Karst Area:A Case of Land Consolidation Project in Libo, Guizhou
    WANG Jun, LI Zheng, BAI Zhongke, GUO Yiqiang, QIU Jie, WANG Guoru
    2011, 30 (7):  906-911.  doi: 10.11820/dlkxjz.2011.07.017
    Abstract ( 951 )   PDF (498KB) ( 975 )   Save
    Land consolidation is a process of re-organizing and re-optimizing of the land resources and land use, and it changes land use types, spatial structure, landscape pattern and ecological process. Therefore it is urgent and important to carry out researches on the landscape ecological protection by land consolidation especially in fragile karst areas. Landscape ecological planning and design can effectively promote the protection and recovery of ecosystems, and such works are involved in land consolidation which is an important trend of development. In the paper, The main points of landscape ecological planning and design in land consolidation are discussed. At the same time, taking a land consolidation project in Libo County, Guizhou as an example, the landscape planning and design of farmland patches, irrigation and drainage engineering, road engineering and biodiversity projection engineering are conducted. The aim of this research is to provide scientific insights into landscape ecological planning and design and the ecological environment impact assessment of land consolidation.
    References | Related Articles | Metrics
    Study on the Suitability of CBR Method in the Estimation of Land Use Change
    SUN Yeran, DU Yunyan, SU Fenzhen, ZHOU Chenghu
    2011, 30 (7):  912-919.  doi: 10.11820/dlkxjz.2011.07.018
    Abstract ( 537 )   PDF (667KB) ( 482 )   Save
    There are various approaches used to study land use change (LUC), such as regression analysis, probability statistics, system dynamics, cellular automata and Bayesian network. These approaches have their specific characteristics and practical applications in the LUC. Although there were some researches revealing the advantages and disadvantages of some approaches, there were relatively few studies on the suitability of these approaches. This study focused on the suitability of CBR approach for LUC estimation, on the basis of the CBR model for the LUC estimation. The comparison experiments were conducted from three aspects, selection approach of the test cases, selection of variables and weights of the variables, to explore the influences of these factors on the estimation accuracy of LUC. The land use changes in Zhuhai region, China during 1995-2000 were used as a case study to conduct the comparative experiments. The concrete comparison strategies include: (1) To choose the test cases by selective approach and stochastic approach to explore the effects of the selection approach on the LUC estimation accuracy; (2) to neglect different variables in turn representing three categories of impacts respectively to explore the effects of the neglect of the variables on the estimation accuracy; (3) to change the weights of variables in turn to explore the effects of the weights of specific variables on the estimation accuracy. The experimental results are shown as follows. Firstly, the selection approach of test cases has insignificant effects on the LUC estimation accuracy under the circumstance that the historical cases are abundant. Secondly, the neglect of the ordinary variables has insignificant influences on the estimation accuracy on the condition that vital variables are selected. Thirdly, the weights of the ordinary variables have insignificant effects on the estimation accuracy in the event that greater weights are assigned to the vital variables. These results demonstrate that CBR is an effective method for solving LUC problems with the advantages of simple construction, wide application, high accuracy and stable pattern. The stability of the LUC estimation accuracy based on CBR approach can be kept on the condition of plentiful historical cases when vital variables are selected and higher weights are assigned to them. In this case, CBR method shows a good suitability for LUC estimation. In addition, the incorporation of the new component“geographic environment”into the CBR model efficiently improves the estimation accuracy of LUC.
    References | Related Articles | Metrics
    Research Progress and Prospective Applications of Vulnerability Approach under Global Change
    LI He, ZHANG Pingyu
    2011, 30 (7):  920-929.  doi: 10.11820/dlkxjz.2011.07.019
    Abstract ( 933 )   PDF (545KB) ( 1122 )   Save
    Based on the analysis of existing literatures on the theme of vulnerability, this paper reviews the evolution and progress of vulnerability research, and analyzes the challenges facing present vulnerability research and the scientific implications of vulnerability approach in coupled human-environment system research. As a new research perspective in the arena of global environmental change and sustainability science, vulnerability approach has attracted extensive attention from scholars in geography and related disciplines, and is moving toward inter-disciplinary and comprehensive studies. Great progresses has been made in vulnerability conception, analytical frameworks, assessment methods and so on, but there is still lack of consummate vulnerability theoretical system and methodology on the basis of merging and crossing of different disciplines. With more and more attentions being paid to the vulnerability of coupled human-environment system under the interactions between human and natural factors, vulnerability approach has significant application value in analyzing the nested scale of human-environment interactions, promoting the integration study of key factors and processes, advancing the merging and crossing of related disciplines, and enhancing the decision support capacity of coupled human-environment system studies.
    References | Related Articles | Metrics
    Research Progress and TUPU Analysis on the Impacts of Land Use on Climate Change
    CHEN Xi, WANG Ziyan, KUANGWenhui
    2011, 30 (7):  930-937.  doi: 10.11820/dlkxjz.2011.07.020
    Abstract ( 636 )   PDF (810KB) ( 878 )   Save
    This paper works on literature co-cited analysis concerning the impacts of land use on climate change based on knowledge visualization tool. The main knowledge clusters and research hot points are concluded. The cluster of climate change's impacts on carbon cycle and soil organic carbon, as well as the relevant research topics, is analyzed. Furthermore, the driving factors and relevant countermeasures influencing global carbon balance under the background of climate change are presented. Using the paradigm in this paper, the integration of knowledge clusters, research topics and driving forces, as well as countermeasures, could be explicitly analyzed towards climate change induced land use change. Besides, it could offer an objective literature foundation for scientific research.
    References | Related Articles | Metrics
    Analysis of Driving Forces of Agricultural Eco-environmental Vulnerability in the Hilly Area in Southern China: A Case Study in Hengyang Basin
    ZHOU Songxiu, TIAN Yaping, LIU Lanfang
    2011, 30 (7):  938-944.  doi: 10.11820/dlkxjz.2011.07.021
    Abstract ( 539 )   PDF (606KB) ( 586 )   Save
    Ecological vulnerability has become a hot issue of the research on the global change and sustainable development. The hilly area of southern China is a typical ecologically fragile area. The paper takes Hengyang Basin as an example, and adopts principal component analysis to study the driving forces of the agricultural eco-environmental vulnerability. First, we define the concept of the agricultural ecology vulnerability (AEV), and analyze the contents of the AEV. Then, based on the characteristics of agricultural eco-environment, we establish the AEV indexes for the Hengyang Basin in the southern China hilly areas, which include natural factors, social factors and economic factors, and take county as the evaluation unit. Principal component analysis is an important method in multivariate statistical analysis. Hence, we adopt this method to study the driving forces of the AEV in this paper, and explore the mechanism that causes the vulnerability. The results show that there are four principal driving forces affecting the vulnerability of agricultural eco-environment of this area. The natural environment and economic development background are the primary driving forces, and living standards and agricultural water facilities are the secondary forces. From the view of driving force type, the stress-type driving force is dominant, and the structure-type driving force is minor. Backward mode of production is a powerful driving force of the AEV.
    References | Related Articles | Metrics