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    25 March 2012, Volume 31 Issue 3 Previous Issue    Next Issue
    Downscaling of Global Mean Annual Temperature under Different Scenairos
    FAN Zemeng, YUE Tanxiang, CHEN Chuanfa
    2012, 31 (3):  267-274.  doi: 10.11820/dlkxjz.2012.03.001
    Abstract ( 738 )   PDF (887KB) ( 717 )   Save
    One of the key issues of global change research is how to improve the simulated data resolution of Global Climate Models (GCMs) for the quantitative analysis of terrestrial ecosystems in response to the climate change at global, regional and local levels. In this paper, the statistcial transfer funcitons are developed by establishing the regression analysis of relation between mean annual temperature and latitude and elevation with the digital elevation models and climate data from global meteorological stations aton global level. The High Accuracy Surface Modelling (HASM) method integrated the statistical transfer functions, is used to downscale the simulated data of HadCM3 from a spatial resolution of 3.75° × 2.5° to 0.125° × 0.125°. The simualted results of A1Fi, A2 and B2 scenarios show that the mean annual temperature would be increasing in the 21st century, the areas in Greenland where the mean annual temperature is below 0℃ and in Antarctica below -35℃ would shrink, and the areas between north and south tropics where the mean annual temperature is higher than 40℃ would expand. The increase rate under scenario A1Fi is the highest and that under scenario B2 is slowest among three scenarios during the period from T1 to T4. The results also show that the coarse resolution data of IPCC GCMs can be availably downscaled to high resolution data by integrating the statistcial transfer funcitons and HASM methods, which could overcome the limitation that the current simulated data resolution of IPCC GCMs can not be used to explain and describe the details of climate change at regional level, especially at local level.
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    Numerical Simulations of Climate Change under IPCC A1B Scenario in Southwestern China
    WU Di, PEI Yuansheng, ZHAO Yong, XIAOWeihua
    2012, 31 (3):  275-284.  doi: 10.11820/dlkxjz.2012.03.002
    Abstract ( 621 )   PDF (3479KB) ( 551 )   Save
    Climate change over southwestern China is simulated by a regional climate model (RegCM3), using the output from a global coupled atmosphere-ocean model (ECHAM5/MPI-OM) as lateral and surface boundary conditions. Two sets of 15 years of simulations at 20-km gird resolution for present days (1986-2000) and future (2011-2025, under IPCC_A1B scenario) are conducted to analyze the effects of surface air temperature and precipitation on the drought as a focal area. Results show that RegCM3 can reproduce well the spatial distribution of surface air temperature and precipitation in southwestern China compared with the observed data of 32 meteorological stations and grid data of CRU, and simulated annual and summer precipitation is much higher than winter precipitation. The simulated precipitation in winter is higher than observed values. During 2011-2025, there might be a remarkably warming either annually or in other seasons. The temperature change in the northern region is bigger than that in the southern region. The maximum and minimum temperature changes in winter are bigger than those in summer. Annually, precipitation increase is consistent with that in autumn and winter, while precipitation increase is significant in winter. Precipitation decrease in spring and summer is not significant. Temperature increase and precipitation decrease in spring and summer might induce high temperature and droughts to parts of the region, while precipitation increase in winter might increase the risk of local flood disasters.
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    Spatial-temporal Variation of NDVI in the Growing Season and Its Sensitivity to Climatic Factors in Changbai Mountains
    HOU Guanglei, ZHANG Hongyan, GUO Dan, GUO Xiaoyi
    2012, 31 (3):  285-292.  doi: 10.11820/dlkxjz.2012.03.003
    Abstract ( 568 )   PDF (746KB) ( 798 )   Save
    In order to reveal the response of mountain ecosystem to climate change, the spatial-temporal distribution of vegetation variation in the Changbai Mountains was investigated by using the 10-day SPOT/VGT NDVI data from 2000 to 2009. Combining the meteorological data, we discussed the relationship between NDVI and climatic factors and time lags of vegetation variation response to climate change. The results are shown as follows. 1) NDVI increased from 2000 to 2009 in Changbai Mountains. The NDVI increased and decreased area covered about 83.91% and 16.09% of the whole study area respectively. The increased area was mainly distributed on the northern and western slopes, while the decreased area was distributed on the southern slope. The growth rate of NDVI centralized 0 - 0.006 /a. 2) The change rate of NDVI varied by seasons and vegetation types. The peak of NDVI slope appeared in May and September, but no increase, even a little decrease was observed in July; 3) There was a significantly positive correlation between NDVI and climatic factors (temperature and precipitation), and NDVI had a closer correlation with temperature than with precipitation for the three vegetation types. The results also revealed that a correlation between NDVI and temperature in tundra zone was stronger than that in the Korean pine-broadleaved mixed forest (700-1100 m) and coniferous forest (1100-1700 m), which indicated that vegetation at higher elevation is more sensitive to temperature change; 4) The correspondence between NDVI and climatic factors had a marked time lag for 10-20 days for the whole study area. Different vegetation types had different time lags. The response of NDVI in tundra zone to climatic factors had a time lag of about 10 days, while in the two forests mentioned above, the response had a time lag of about 20 days.
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    Climatological Calculation of Land Surface Atmospheric Water Vapor Content in Longitudinal Range-gorge Region
    PAN Tao, WU Shaohong, LIU Yujie, DAI Erfu
    2012, 31 (3):  293-302.  doi: 10.11820/dlkxjz.2012.03.004
    Abstract ( 557 )   PDF (1273KB) ( 586 )   Save
    Based on the monthly meteorological data of the upper air from 1976 to 2005, we analyzed the statistical relationship between land surface vapor pressure and atmospheric water vapor content and built a ground-based atmospheric water vapor content climatology model. Combined with ground meteorological data, actual surface vapor pressure of different stations was calculated in Longitudinal Range-gorge Region. Then, an ANUSPLIN climate interpolation model was used for the spatial interpolation of surface water vapor pressure, to make a grid of land surface vapor pressure. At last, the gridded land surface vapor pressure data was inputted into the climatology model to simulate the spatial pattern of land surface atmospheric water vapor content and realize the spatial simulation of the atmospheric water vapor content. The spatial distribution and its main causes of land surface water vapor pressure and atmospheric water vapor content were discussed. The results showed that longitudinal mountains have a significant barrier function to the vertical transport of water vapor, which leads to the horizontal differences of the surface water vapor pressure and atmospheric water vapor content. Deep north-south valley is an important corridor for the transportation of water vapor transmission. The "corridor-barrier" function of this region forms the special spatial pattern of the atmospheric water vapor content.
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    Review of Ecosystem Resilience Research Progress
    YAN Haiming, ZHAN Jinyan, ZHANG Tao
    2012, 31 (3):  303-314.  doi: 10.11820/dlkxjz.2012.03.005
    Abstract ( 953 )   PDF (511KB) ( 1345 )   Save
    Due to the climate change and human activities, the global ecosystem has changed significantly, which leads to the decline of ecosystem resilience at the regional and even global scale and constrains the sustainable development of ecosystems. The question about how to maintain the sustainable development of ecosystems and reduce the influence of uncertainties has aroused great concern from the academic community and people from all walks of life. A theory based on ecosystem resilience has provided a framework for solving these problems for the ecosystem resilience provides measures to alleviate the ecosystem deterioration. Although the significance of the concept of ecosystem resilience in management has been widely accepted, the research on ecosystem resilience still remain stagnant in the mode of the conceptual analysis and case studies and there is still no consensus on the concept of ecosystem resilience. Previous researches are generally theoretical analyses and even fewer researchers have quantitatively measured ecosystem resilience. The quantitative measurement of ecosystem resilience has become the key step and breakthrough point for further exploration of the ecosystem resilience. This paper reviewed the development process of the concept of ecosystem resilience and illustrated current viewpoints on the concept, meaning and properties of ecosystem resilience. The current theories of ecosystem resilience were stated and some attempts of quantitative measurement of ecosystem resilience were discussed. This paper also summarized the influencing factors of ecosystem resilience that have been found in relevant researches, and their influencing mechanism was also analyzed. Finally the future research were perspected.
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    Lake Nutrient Concentration Oriented Ecological Division Based on Remote Sensing Inversion Parameters and Dual-constraint Spatial Clustering Algorithm
    KE Xinli, LIU Man, DENG Xiangzheng
    2012, 31 (3):  315-323.  doi: 10.11820/dlkxjz.2012.03.006
    Abstract ( 521 )   PDF (910KB) ( 551 )   Save
    Abstract: There exist remarkable regional differences on the lake nutrient and its eutrophication effect in China. It is the premise to explore the features of lake nutrient and its determinacy on the ecological division to carry out effective measures on the breaking-out of lake eutrophication. In the case study of Yunnan-Guizhou Plateau, the contents of Chlorophyll-a(Chl-a), total nitrogen (TN) and total phosphorus (TP) of lake water are inverted via the remote sensing inversion algorithm. An index system is also established by including the information from geophysical, geographical, ecosystem and human dimensions to evaluate the levels of land nutrients and all the information is mapped onto the small watersheds delimitated based on DEM data covering the entire study region. Meanwhile, the effect of each index on the ratio of Chl-a over P (Chl-a/P) and the ratio of chl-a over N(Chl-a/N) is quantitatively analyzed by applying mathematical statistics method on the small watershed scale so as to calculate the evaluation scores of two lake nutrient ecological zones who will then be clustered according to the small watershed scale via the dual-constraint space clustering algorithm. After a couple rounds of handlings, ecological zones reflecting the pattern of the lake nutrient concentrations are finally formed.
    The paper concludes a couple of key findings. A small number of sites based monitoring data can be used to deduce the surface of lake nutrient level through the remote sensing inversion model, which makes up the deficiency that the few sites-based monitoring data are always hard to supply enough information for the lake nutrient ecological division. By exploring the relationship between each index factor and Chl-a/P and Chl-a/N on the lake water, organic combination of microscopic indexes of the lake water and macroscopic indexes of the watersheds on the lake nutrient ecological division is thus realized. By applying the dual-constraint spatial clustering algorithm to carry on the lakes nutrient ecological zoning to meet the requirements of space continuity kept while the evaluation scores are guaranteed. Corresponding to the spatial difference of geophysical and geographical conditions, land use and human intervention intensity, the Yunnan-Guizhou Plateau is divided into four ecological parts, i.e., north Yunnan Plateau lakes, the southern Yunnan valley, mountain lakes and karst lakes zones located between east Yunnan, west Guangxi and south Guizhou and northeast Guizhou plateau. The study indicates that the lake nutrient ecological division approach base one dual-constraint space clustering algorithm can be used to other places and be recommended as reference approach of the lake nutrient ecological division to multiple scales of areas.
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    The Application of Attribute Recognition Model Based on Coefficient of Entropy to the Assessment of Seawater Intrusion
    LI Miao, XIA Jun, LI Fulin, MENG Dejuan
    2012, 31 (3):  324-329.  doi: 10.11820/dlkxjz.2012.03.007
    Abstract ( 474 )   PDF (675KB) ( 548 )   Save
    In this study, to solve the question of the one-sidedness and uncertainties when taking an assessment of seawater intrusion by using a single index (such as Cl- or mineralization), an attribute recognition model based on coefficient of entropy theory was built to take an assessment of seawater intrusion in coastal areas, and take a sample application of eight measured wells for seawater intrusion in plain north of Weifang. It is found that the intrusion was mild in most parts of plain north of Weifang where the water quality is brackish water, and more serious intrusion occurred in May, and changed back to mild intrusion in November in the eastern part of the study area (locations No.6 and No.8). There are two possible reasons responsible for this change. The first one is natural factors which include precipitation increases and sea level falls from May to November. The second reason is human activities mainly due to the reduction of groundwater pumping. Meanwhile, there are small differences in the rank of eight measurement wells for seawater intrusion in May and November. The sample application shows that this model is easy to understand and master, and that it provides a feasible and effective method for the assessment of seawater intrusion.
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    Assessment of Water Conservation Function of Forest Ecosystem in Taihe County, Jiangxi Province
    WU Dan, SHAO Quanqin, LIU Jiyuan
    2012, 31 (3):  330-336.  doi: 10.11820/dlkxjz.2012.03.008
    Abstract ( 561 )   PDF (724KB) ( 603 )   Save
    Water conservation is an important function of forest ecosystem, which could weaken rainfall erosivity, slow down surface runoff and preserve soil and water. It is a comprehensive effect of three main hydrological processes, namely canopy interception, litter containment, and soil water storage. On the basis of the sixth inventory data of forest resources (2003) in Taihe County, Jiangxi Province and literature reviews, this paper estimated the function of water conservation and its spatial distributions and variations. Also, we compared the water conservation capacity of forest ecosystem through three layers by forest types, age groups, elevations and slopes. The results showed that, the canopy layer could intercept approximately 16.31% of rainfall; the litter layer could hold 2.14% of water and the soil layer could store 81.55% of water. It can be seen that that soil layer is the main aquifer of forest ecosystem. The total amount of rainfall interception and water holding was 141 million cubic meters in Taihe. The amount of water conserved by different vegetation types in a descending order was Cunninghamia lanceolata forest > Pinus massoniana forest > Pinus elliottii forest > Broad-leaved forest > Phyllostachys pubescen forest > Shrubby forest >Mixed forest > Economic forest. The contribution rate of water conservation of young stand, middle-aged stand, near-mature stand, mature stand and over-mature stand forests was 17.58%, 65.39%, 14.18%, 2.48% and 0.37%, respectively. The capacity of water containment increased with the increasing age of forest. The spatial distribution of water conservation capacity of forest ecosystem in Taihe tended to decrease from eastern and western to the central part. The damage of forest vegetation or soil could lead to water loss and soil erosion, and even natural disasters. Therefore, reasonable management of forest ecosystem under different conditions would play an essential role in the enhancement of water conservation function.
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    Study on the Estimation of Regional Oxygen Production: A Case Study in Harbin
    ZHANG Lijuan, MAJun,YAN Xiaodong, LIU Dong, ZHANG Li
    2012, 31 (3):  337-343.  doi: 10.11820/dlkxjz.2012.03.009
    Abstract ( 474 )   PDF (807KB) ( 502 )   Save
    With the recent advancement in climate change research, it is imperative to examine the dynamic of oxygen concentration in the atmosphere. This research, therefore, attempted to estimate the regional oxygen production by simulating various levels of plant productivities in Harbin, Heilongjiang Province, China, using the photosynthesis principle. In particular, the total amount and spatial distribution of oxygen production within Harbin were estimated using the net primary productivity (NPP) and net ecosystem productivity (NEP). The NPP and NEP, in turn, were estimated employing the C-FIX model with the help of MODIS Net Primary Production (NPP) product. Several conclusions can be drawn as follows. Firstly, in 2008, the total net oxygen production in Harbin was 394423.95 tons. For oxygen consumption, autotrophic respiration accounted for 30.787% of the initial oxygen production, and heterotrophic respiration consumption was negligible (0.001%).We also found that the more initial oxygen production was, the more consumption through plant respiration. Secondly, oxygen production in Harbin has distinct seasonal variations. The production is near zero in winter (from December to February), medium in autumn and spring (slightly higher in autumn), and highest in summer. Finally, oxygen production also has apparent spatial patterns. Within Harbin City, Acheng District has the highest monthly and annual oxygen production, followed by Hulan and Songbei districts, while the old districts, including Nangang, Daoli, Daowai, Xiangfang and Pingfang, have the lowest level. In summary, this paper estimated the daily, monthly, and annual net oxygen production and examined their spatial distribution dynamics by applying the photosynthesis principle with the help of remote sensing (RS) and geographic information system (GIS) technologies. This research proposed a new idea for regional oxygen production estimation, thus providing a basis for studying the dynamics of regional oxygen concentration, and evaluating regional environmental quality for supporting human life.
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    Research on Vulnerability Assessment of Human-land System of Anshan City Based on Set Pair Analysis
    HAN Ruiling, TONG Lianjun, TONGWeiming, YU Jianhui
    2012, 31 (3):  344-352.  doi: 10.11820/dlkxjz.2012.03.010
    Abstract ( 568 )   PDF (734KB) ( 630 )   Save
    Vulnerability assessment framework in sustainability science has properties of multi-scale, multi-element, multi-flow and multi-cycle, so vulnerability assessment is a new research paradigm in the realms of global environmental change and sustainable development, and provides an effective tool for the study of interaction mechanisms and processes of coupled human-land system. Based on the dependence of economic development on resources, and the instability in employment, and the ecology being relatively disrupted, the vulnerability assessment indexes of Anshan city are established. By using the set pair analysis and the entropy method, the essay analyzed the sensitivity, response capacity and vulnerability level of the economic system, as well as the employment system and the ecosystem. Then the vulnerability of human-land system of Anshan city are tested and the evolution of vulnerability characteristics during 1990 to 2009 has been revealed.
    The relationship of human-land system of Anshan city belongs to the lower sensitivity and higher response capacity type. In comparison with other resource-based cities in Northeast China, the human-land stability of Anshan city is stronger, and the vulnerability is relatively weak, which means that Anshan city has lower sensitivity and better response capacity to the complicated human-land system. The sensitivity of Anshan city has a declining trend, and the economic sensitivity is bigger than the environmental sensitivity and the social sensitivity. The response capacity of Anshan city shows a rising trend, and the environmental system is more evident than the social system and the economic system. There is a rising trend for vulnerability of Anshan, and economic system is most vulnerable. The paper reflects that Anshan city has better potentials to develop a sustainable economy, but attention should be paid to lowering the sensitivity of the economic system and to increasing the response capacity.
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    Soft Hierarchical Model of Integrated Risk Assessment for Multi-hazards: Taking Earthquake and Flood Disasters in Lijiang, Yunnan as a Case Study
    XUE Ye, CHEN Baozhang, HUANG Chongfu, YAN Jianwu
    2012, 31 (3):  353-360.  doi: 10.11820/dlkxjz.2012.03.011
    Abstract ( 662 )   PDF (642KB) ( 667 )   Save
    Integrated risk assessment is one of the important parts of integrated risk management, which can help governments to take maeasures on preventing and mitigating the losses of disasters. What's more, multi-hazards integrated risk assessment is currently very important and difficult in the field of disaster reduction at home and abroad, with the systematic theory and methodology not yet obtained. Based on the system theory of disaster risk, this study has introduced the methods of fuzzy information granulation and fuzzy transformation function, and built a soft hierarchical model of integrated risk assessment for multi-hazards, which is characterized by the following aspects. 1) Not only the certainty of disaster risk, but also the random uncertainty and fuzzy uncertainty are considered. 2) The approach of fuzzy information granulation can reduce the uncertainty of data, and it includes some subjective information so as to make the results of assessment more realistic, theory and practice more tightly combined, and thus, it is more conducive to risk managers and decision makers to provide the basis of loss reduction and risk aversion. 3) Fuzzy transformation function transforms different types of quantity into the same type of quantity in order to comprehensively analyze and obtain the assessment result of multi-hazards integrated risk. Using earthquake-flood disaster risk as a case study, the demonstration analysis of soft hierarchical model of integrated risk assessment for earthquake-flood disaster illustrates that this soft hierarchical model suggested in this study holds the ability of synthetically assessing multiple disasters.
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    An Overview of the Risk Assessment of Flood Disaster
    LIAO Yongfeng, NIE Chengjing, YANG Linsheng, Li Hairong
    2012, 31 (3):  361-367.  doi: 10.11820/dlkxjz.2012.03.012
    Abstract ( 862 )   PDF (448KB) ( 1115 )   Save
    Along with the global warming, flood disasters occur more frequently. Monitoring, early warning and assessment for disaster risk are an important way to reduce disaster losses. So it is one of the core issues in the current disaster research. On the basis of the analysis of the disaster risk, this paper described the concept, the content of warning and assessment, and ways of assessment and methods of flood disaster warning in China. This paper argued that in order to reduce flood hazard and the uncertainty of vulnerability analysis, we should explore the mechanism of flood disaster. In addition, monitoring technology was so important for risk assessment that we should improve sensor performance to increase accuracy; integrate multi-source remote sensing data; develop the "3S" integrated technology.
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    GIS-based Analysis of Earthquake Disaster Population Risk in China
    LIU Huan, XU Zhongchun, WU Shaohong, LIU Ronggao
    2012, 31 (3):  368-374.  doi: 10.11820/dlkxjz.2012.03.013
    Abstract ( 792 )   PDF (675KB) ( 751 )   Save
    Since the earthquake disaster frequently occurred in China, it is necessary to do some research on the risk analysis of earthquake. The paper first analyzed major factors of earthquake disaster, then established earthquake disaster risk assessment model based on the data of earthquake disasters between 1900 and 2009, and determined the value of three factors quantitatively. Finally, through using the spatial analyst function of ArcMap system, this paper analyzed the risk of population in earthquake disaster and created the population risk distribution map with a division of population high risk areas.
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    Macro Assessment of Seismic Population Vulnerability in China
    NIE Chengjing, YANG Linsheng, Li Hairong
    2012, 31 (3):  375-382.  doi: 10.11820/dlkxjz.2012.03.014
    Abstract ( 765 )   PDF (709KB) ( 615 )   Save
    Seismic vulnerability assessment is not only the basis for a long-term planning, but also provides support for emergency decision-making in earthquake emergency, therefore it is a focus in current research of vulnerability. First, this paper introduced the definition of seismic population vulnerability, and proposed its vulnerability factors and influence patterns. Second, after researching the macro and micro assessment models and methods of seismic population vulnerability, the macro assessment model of seismic population vulnerability was established by using five indicators, which are the total population, proportion of the young, proportion of the the old, population density and per capita GDP. The seismic population vulnerability at county level was assessed across China. The results showed that the differences of seismic population vulnerability were significant, the vulnerability in the eastern region was higher than that in the western, and the total population was the key factor. The assessment model designed in this paper had a significant effect on the amendment to the population vulnerability of the earthquake.
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    A Study on Theory and Method in Debris Flow Risk Assessment
    LIU Guangxu, DAI Erfu, WU Shaohong, WUWenxiang
    2012, 31 (3):  383-391.  doi: 10.11820/dlkxjz.2012.03.015
    Abstract ( 944 )   PDF (640KB) ( 1048 )   Save
    The frequent occurrences of debris flow disasters have caused great damage in some regions of China during recent years. Yet it is difficult to forecast such disasters accurately due to its big quantity in large area and sudden outbreak. Therefore it is especially urgent to pre-evaluate debris flow disaster risk. This paper reviewed the research on debris risk assessment in the past decades, including its conceptual constituents, hazard assessment and vulnerability evaluation. It was found that a tangible disaster risk assessment formula had been formed and debris flow hazard assessment methods had been successfully established. However, there were still some problems which need to be further explored, such as the mechanism analysis of the damage risk to hazard-bearing items, the effective transition from the point evaluation to the regional one, the neglected vulnerability research. Hence, it might be necessary to strengthen research in these aspects in the future, which might consequently enhance the reliability of the risk assessment results and improve its practicality.
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