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Stochastic modelling of soil moisture dynamics in a grassland of Qilian Mountain at point scale

Science china Earth sciences 2007年第12期50卷 1844-1856页

作者： LIU Hu,ZHAO WenZhi HE ZhiBin & ZHANG LiJie Linze Inland River Basin Research Station,chinese Ecosystem Research Network laboratory of watershed hydrology and ecol-ogy,Cold and Arid Regions Environmental and Engineering Research Institute,chinese academy of sciences,{3.,china Linze Inland River Basin Research Station Chinese Ecosystem Research Network China laboratory of watershed hydrology and {3.ogy Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

Stochastic modeling of soil moisture dynamics is crucial to the quantitative understanding of plant responses to water stresses,hydrological control of nutrient cycling processes,water competition among plants,and some other ecological dynamics,and thus has become a hotspot in ecohydrology at *** this paper,we based on the continuously monitored data of soil moisture during 2002―2005 and daily precipitation date of 1992―2006,and tried to make a probabilistic analysis of soil moisture dynamics at point scale in a grassland of Qilian Mountain by integrating the stochastic model improved by Laio and the Monte Carlo *** results show that the inter-annual variations for the soil moisture patterns at different depths are very significant,and that the coefficient of variance(CV) of surface soil moisture(20 cm) is almost continually kept at about 0.23.whether in the rich or poor rainy ***,it has been found that the maximal CV of soil moisture has not always appeared at the surface *** of the analytically derived soil moisture probability density function(PDF) with the statistical distribution of the observed soil moisture data suggests that the stochastic model can reasonably describe and predict the soil moisture dynamics of the grassland in Qilian Mountain at point *** extracting the statistical information of the historical precipitation data in 1994―2006,and inputting them into the stochastic model,we analytically derived the long-term soil moisture PDF without considering the inter-annual climate fluctuations,and then numerically derived the one when considering the inter-annual fluctuation effects in combination with a Monte-Carlo *** was found that,though the peak position of the probability density distribution significantly moved towards drought when considering the disturbance forces,and its width was narrowed,accordingly its peak value was increased,no significant bimodality was observed in the soil moistur

关键词： soil moisture dynamics, stochastic modelling, Monte Carlo method, probability density function, grassland ecosystem

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STUDY ON TREND PREDICTION AND VARIATION ONTHE FLOW INTO THE LONGYANGXIA RESERVOIR

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chinese Geographical Science 2001年第1期11卷 35-41页

作者： LAN Yong-chao, KANG Er-si, MA Quan-jie, ZHANG Ji-shi (Cold and Arid Regions Environment and Engineering Research Institute, the chinese academy of sciences, lanzhou 730000, P. R. china {3. Administrative Office of hydrology and Water Resources of t Cold and Arid Regions Environment and Engineering Research Institute the Chinese Academy of Sciences Lanzhou P.R. China lanzhou Administrative Office of hydrology and Water Resources of the Upper Reaches of the Huanghe River Lanzhou P. R. China

The Longyangxia Gorge Key Water Control System is the first of the stairstep power sations along the Longyangxi- a-Qingtongxia river section. It has been playing an very important role in providing power, protecting flood and ice run supplying and irrigation etc. in the northwestem china. Therefore, the study on trend prediction, variation on the now into the Longyangx- ia Reservoir are of the great social and economic benefits. In the medium- and-long-range runoff forecast, all kinds of regression equation are often used for predicting future hydrologic regime. However, these regression models aren’ t appropriate to super long -range runoff forecast because of the restricting on weather data and so on. So a new super long-range runoff forecast model don’ t depend on Real-time weather data and called" Period correcting for residual error series GM(1,1 ) model" is presented based on analyzing for the relational hydrologic data and the variation on the now into the Longyangxia Reservoir, and the fore- cast model was applied successfully to predict the recent and super long -term trends of the flow into the Longyangxia Reservoir. The results indicate that the annual now into the Longyangxia Reservoir is in the ending minimum period of the runoff history. The runoff increasing is expected in for the coming years.

关键词：流动变化趋势预言剩余错误系列 Longyangxia 水库

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Differential Hydrological Grey Model (DHGM) with self-memory function and its application to flood forecasting

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Science china(Technological sciences) 2009年第4期52卷 1039-1049页

作者： CHEN XiangDong1, XIA Jun1,2 & XU Qian3.1 Key laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, {3. 2 State Key laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 43.072, {3. 3.School of hydrology and Water Resources, Hohai University, Nanjing 210098, {3. Key laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China State Key laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan China School of hydrology and Water Resources Hohai University Nanjing China

This paper addresses a problem of flood forecasting with the self-memory function. Considering flood forecasting’s uncertainty and updating demand, a hybrid hydrological model, namely Differential Hy- drological Grey Model with self-memory function (DHGM-SM), is developed. The model has two fold features. One is to establish a self-memorization equation linked with DHGM, that could extract useful information from past data series and realize updating of hydrological dynamic process. The other is that this model has higher efficiency relative to original hydrological model without self-memory func- tion. This approach was applied to river flow forecasting of two representative basins in Tunxi of South china and Daqinggou of North china. It is shown that this hybrid method has satisfactory forecasting accuracy by examination of both calibration and validation.

关键词： differential grey model the self-memorization principle real-time forecasting faded-memory recursive least square method

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ecological response to the climate change on the northern slope of the Tianshan Mountains in Xinjiang

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Science china Earth sciences 2005年第6期48卷 765-777页

作者： CHEN Xi1, LUO Geping1, XIA Jun2, ZHOU Kefa1, LOU Shaoping3.& YE Minquan4 1. Xinjiang Institute of ecology and Geography, chinese academy of sciences, Urumqi 83.011, {3. 2. Institute of Geographical and Resources {3., chinese academy of sciences, Beijing 100101, {3. 3. Urumqi Meteorological-satellite Land Station, Urumqi 83.011, {3. 4. Seismological Bureau of Xinjiang Uygur Autonomous Region, Urümqi 83.011, {3. Correspondence should be addressed to Chen Xi Xinjiang Institute of ecology and Geography Chinese Academy of Sciences Urumqi China Institute of Geographical and Resources sciences Chinese Academy of Sciences Beijing China Urumqi Meteorological-satellite Land Station Urumqi China Seismological Bureau of Xinjiang Uygur Autonomous Region Urümqi China

The Tianshan Mountains is a high and huge mountain body lying across the central part of Xinjiang, china, and is also the main area where the runoff forms in Xinjiang. In this paper, a set of RS-based study methods is put forward for deriving the information about the natural change of the ecology in arid areas, and the relationship between the climate change trend and the corresponding ecological response on the northern slope of the Tianshan Mountains since recent 40 years is analyzed from the scales of the land cover ecosystems and landscapes based on the observed data of climate, {3., modern glaciers and lakes on the northern slopes of the Tianshan Mountains since recent 40 years and the satellite RS data since recent 10 years by using the RS and GIS technologies. The results are as follows: (1) The overall trend of climate change on the northern slope of the Tianshan Mountains since recent 40 years is that both air temperature and precipitation are increased, especially the increase amplitudes of air tempera-ture, precipitation and annual runoff volume are high since the decade of the 1990s; (2) the in-tegrated indexes of the vegetation in all the geographical divisions on the northern slope of the Tianshan Mountains are obviously increased since recent 10 years, especially in the artificial oases and the foothill belts, such a change trend is advantageous for improving the vegetation ecology; and (3. the vegetation ecology in the arid areas is extremely sensitive to the climate change, the vegetation coverage and the biomass on the northern slope of the Tianshan Moun-tains are continuously increased because of the climate change since recent 10 years, their in-crease amplitudes in the plains and during the late stage are obviously higher than that in the mountainous regions and during the early stage.

关键词： north slope of the Tianshan Mountains, climate change, hydrological change, natural change of ecology,RS and GIS, vegetation index.

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Isotope Method for Confined Groundwater Recharge of the Lower Reaches of the Heihe River,Inner Mongolia,china

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Acta Geologica Sinica(English Edition) 2007年第4期81卷 668-673页

作者： CHEN Jiansheng ZHAO Xia FAN Zhechao and WANG Jiyang 1 State Key laboratory of hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,china 2 Institute of Isotope hydrology Research,Hohai University,Nanjing 210098,china 3.Institute of Geology and Geophysics,chinese academy of Science,Beijing 100018,china Hohai Univ Stae Key Lab Hydrol Water Resources & Hydraul E Nanjing 210098 Peoples R China Hohai Univ Inst Isotope Hydrol Res Nanjing 210098 Peoples R China chinese Acad Sci Inst Geol & Geophys Beijing 100018 Peoples R China

Environmental isotopes have been appfied to analyze confined groundwater recharge in the lower reaches of the Heihe River, Inner Mongolia. CFC is regarded as a tracer that determines the date of groundwater, the date being less than 45 a. The confined groundwater within the Gurinai area and Ejin Basin other than the surface water of Heihe River might have originated from precipitation from Qilian Mountain or/and the Tibetan Plateau. The deep confined groundwater overflows into an upper aquifer and emerges into the ground, forming springs and lakes within the low-lying area. The recharge volume is estimated to be around 400 million-cubic meters.

关键词： isotope CFC Ejin Basin Gurinai groundwater recharge precipitation Qilian Mountain

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Study on the changes of water cycle and its impacts in the source region of the Yellow River

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Science china(Technological sciences) 2004年第Z1期47卷 142-151页

作者： ZHANG Shifeng1, JIA Shaofeng1, LIU Changming1, CAO Wenbing2, HAO Fanghua3. LIU Jiuyu4 & YAN Huayun5 1. Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, china 2. china University of Geosciences, Beijing 100083. china 3. Beijing Normal University, Beijing 100875, china 4. Bureau of hydrology of Yellow River Conservancy Commission, Zhengzhou 450003. china 5. Bureau of hydrology and Water Resource Investigation of Qinghai Province, Xining 810001, china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China china University of Geosciences Beijing China Beijing Normal University Beijing China Bureau of hydrology of Yellow River Conservancy Commission Zhengzhou China Bureau of hydrology and Water Resource Investigation of Qinghai Province Xining China

The water cycle in the source region of the Yellow River underwent great changes in the 1990s. The major features of the changes are as follows: the gauged runoff declined significantly while the precipitation increased slightly, and the runoff process was more concentrated on the flood season. Water balance analyses indicate that the pondage was kept in the status of negative equilibrium, causing eco-environmental problems. The runoff decrement is due to evaporation increment in this region. Studies show that the runoff process in this region is closely related to that of the other hydrological stations in the upper reaches. When the runoff declines in the source regions, the amount of water also declines in the whole upper reaches of the Yellow River, affecting the balance between water demand and supply. Meanwhile changes will take place in the water cycle of the river course system when the eco-environment deteriorates. The trend of water cycle change in the source region is that the runoff will keep declining with the increment of evaporation caused by temperature rise in the northwest of china in the 21st century. But the hydraulic engineering in the source region will help to mitigate the deterioration of local eco-environment system, though the impacts to the lower reaches of this project may not be the case.

关键词： source region of the Yellow River, water cycle, evaporation, negative equilibrium.

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Dissolved inorganic carbon and CO_(2) fluxes across Jiaozhou Bay air-water interface

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Acta Oceanologica Sinica 2004年第2期23卷 279-285页

作者： LIXuegang LINing GAOXuelu SONGJinming InstituteofOceanology ChineseAcademyofSciencesQingdao266071China GraduateSchool ChineseAcademyofSciencesBeijing100039China

On the basis of data collected in the Jiaozhou Bay in June and July 2003. the DIC distribution in seawater is studied, and an average air-sea flux of CO2 is estimated. The results show that the content of DIC inside the bay is markedly higher than outside the bay in June, but the content of DIC outside the bay is markedly higher than inside the bay in July. The trend of DIC distribution inside the bay is similar, viz. the content is the maximum in the northeast, then decreases gradually toward the west, and the content is the minimum in the west. The total trend of vertical distribution is to increase gradually from surface to bottom. This characteristic of DIC distribution is determined by Jiaozhou Bay hydrology and there is a close relation between DIC and particulate N,P. Average CO2flux across the air-sea interface is 0.55 mol/(m2-a) in June and 0.72 mol/(m2-a) in July. Jiaozhou Bay is considered as a net annual source for atmospheric CO2 in June and July, and the total CO2 flux from seawater into atmosphere is about 740t in June and 969 t in July.

关键词： DIC flux of CO_2 Jiaozhou Bay

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ecological Economic Problems and Development Patterns of the Arid Inland River Basin in Northwest china

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AMBIO－人类环境杂志 2006年第6期35卷 316-318页

作者： Lihua Zhou Key laboratory of Desert and Desertification,Cold and Arid Regions Environmental and Engineering Research Institute,chinese academy of sciences,3.0 Dong Gang West Road,lanzhou 730000,People’s Republic of {3. lhzhou@lzb.ac.cnGuojing Yang laboratory of watershed hydrology and ecology,Cold and Arid Regions Environmental and Engineering Research Institute,chinese academy of sciences,3.0 Dong Gang West Road,lanzhou 730000,People’s Republic of {3. ygj7518@*** 中国科学院寒区旱区环境与工程研究所荒漠与荒漠化重点实验室

中国西北部干旱区的内陆河流域位于欧亚大陆的中心（3.°N，106°E），占全国陆地总面积的24.5％，是世界上最干旱的地区之一。该区具有较为湿润的山地和干旱的平原地带性交替特征。发源于山区的几条河流，如黑河、石羊河．疏勒河和塔... 详细信息

中国西北部干旱区的内陆河流域位于欧亚大陆的中心（3.°N，106°E），占全国陆地总面积的24.5％，是世界上最干旱的地区之一。该区具有较为湿润的山地和干旱的平原地带性交替特征。发源于山区的几条河流，如黑河、石羊河．疏勒河和塔里木河，在流经中游地区，孕育了一些生机盎然的绿洲后，注入一些小的湖泊或者消失在广袤的干旱荒漠盆地。山地．绿洲和沙漠相间分布的景观特征是中国西北干旱区内陆河流域典型的景观格局。尽管该区相对于其他的干旱地区来说有较多的农牧业生产活动，水资源问题仍然是限制该区经济发展的重要影响因素。我们以黑河流域作为一个案例，

关键词：西北干旱区内陆河流域中国西北部经济问题生态景观特征黑河流域水资源问题

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Spatial Distribution of Land Cover and Vegetation Activity along Topographic Gradient in an Arid River Valley, SW china

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Journal of Mountain Science 2009年第3期6卷 274-285页

作者： LIU Wen XU Xianli LUO Jiancheng SHEN Zhanfeng ZHONG Qiuhai Department of Automatic Control School of Automation Beijing Institute of Technology Beijing 100081 China State Key laboratory of Urban and Regional ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Centre for hydrology Micrometeorology and Climate Change Department of Civil and Environmental Engineering University College Cork Cork Ireland

Anthropogenic activities have become more and more important in characterizing the landscape, but their impacts are still restricted by natural environments. This paper discusses the interactions of anthropogenic activity, vegetation activity and topography through describing the spatial distribution of land cover and vegetation activity (represented by Normalized Difference Vegetation Index, NDVI) along topographic gradient in a mountainous area of southwestern china. Our results indicate that the existing landscape pattern is controlled by anthropogenic activities as well as topographic factors. Intensive anthropogenic activities mainly occur in areas with relatively low elevation, gentle and concave slopes, as these areas are easy and convenient to attain for human. Because of the destruction by human, some land cover types (mainly grassland and shrub) are only found in relatively harsher environments. This study also finds that topographic wetness index (W) used in other places only reflects runoff generation capacity, but not indicate the real spatial pattern of soil water content in this area. The relationships between NDVI and W, and NDVI and length slope factor (LSF) show that runoff and erosion have complex effects on vegetation activity. Greater values of W and LSF will lead to stronger capacity to produce runoff and transport sediment, and thereby increase soil water content and soil deposition, whereas beyond a certain threshold runoff and erosion are so strong that they would destruct vegetation growth. This study provides information needed to successfully restore native vegetation, improve land management, and promote sustainable development in mountainous areas, especially for developing regions.

关键词：空间分布植被活动土地覆盖流域梯度干旱地形中国

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The role of social resource of indigenous people in local ecological resource management in china: A preliminary case in Zhangye, Northwestern china

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Research in Cold and Arid Regions 2009年第3期1卷 277-285页

作者： YuWen Li 1,2, ZhongMin Xu 1, HuaiWen Cheng 1 1. laboratory of watershed hydrology and {3.ogy, Cold and Arid Regions Environmental and Engineering Research Institute, chinese academy of sciences, lanzhou 730000, china. 2. Zhejiang University of Finance and Economics, Hangzhou, Zhejiang 3.0018, china. chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Lab Watershed Hydrol & Ecol Lanzhou 730000 Gansu Peoples R China Zhejiang Univ Finance & Econ Hangzhou 310018 Zhejiang Peoples R China

Social resources of indigenous people are valuable wealth, including the social norms, the relational network, belief, attitude as well as the social system which is accumulated from generation to generation. Those social resources are very important for local ecological resource management, which can help diffuseness and communion of skills and traditional conservation techniques for conserving and restoring the ecological sites. Social capital is one indicator of social resources, which is accepted widely. In order to investigate the role of social resources of indigenous people in local ecological resource management, the authors studied the relation between social capital of indigenous people and local ecological resource management, taking Zhangye City as an exam-ple. In this paper, social capital of indigenous people is quantified by constructing social capital index, composed of structural so-cial capital and cognitive social capital; local ecological resource management is quantified by constructing 'Grain for Green Pro-ject' performance index. Based on correlation analysis approach and logistic regression analysis approach, the authors analyzed the relation between social capital and 'Grain for Green Project' performance index, as well as the relations between 'Grain for Green Project' performance index and other factors such as per capita net income, medical treatment and so on. Results showed that the correlation between social capital and 'Grain for Green Project' performance index was positive, the coefficient was 0.761, with P3.912, 1.03. and 1.005 units, respectively.

关键词： social capital Grain for Green Project ecological resource management Zhangye City

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