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The study on Sanmenxia annual flow forecasting in the Yellow River with mix regression model

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Science China(Technological sciences) 2004年第z1期47卷 118-126页

作者： JIANG Xiaohui1, LIU Changming1,2. WANG Yu3.& WANG Hongrui1 1. beijing Normal University, beijing 100875, China 2. {2. of geographic Science and Natural resources, Chinese Academy of sciences, beijing 100101, China 3. Reconnaissance, Planning, Design and research {2., YRCC, Zhengzhou 450003. China beijing Normal Univ Beijing 100875 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China YRCC Reconnaissance Planning Design & Res Inst Zhengzhou 450003 Peoples R China

This paper established mix regression model for simulating annual flow, in which annual runoff is auto-regression factor, precipitation, air temperature and water consumption are regression factors; we adopted 9 hypothesis climate change schemes to forecast the change of annual flow of Sanmenxia Station. The results show : (1) When temperature is steady, the average annual runoff will increase by 8.3. if precipitation increases by 10%; when precipitation decreases by 10%, the average annual runoff will decrease by 8.2.; when precipitation is steady, the average annual runoff will decrease by 2.4% if temperature increases 1℃; if temperature decreases 1℃, runoff will increase by 1.2.. The mix regression model can well simulate annual runoff. (2. As to 9 different temperature and precipitation scenarios, scenario 9 is the most adverse to the runoff of Sanmenxia Station of Yellow River; i.e. temperature increases 1℃ and precipitation decreases by 10%. Under this condition, the simulated average annual runoff decreases by 10.8%. On the contrary, scenario 1 is the best to the enhancement of runoff; i.e. when temperature decreases 1 ℃ precipitation will increase by 10%, which will make the annual runoff of Sanmenxia increase by 10.6%.

关键词： forecast annual flow, mix regression model, Sanmenxia Station

Relationships between tree-ring width index and NDVI of grassland in Delingha

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Chinese Science Bulletin 2006年第9期51卷 1106-1114页

作者： HE Jicheng1,3.& SHAO Xuemei1,2.. institute of geographical {2. and Natural resources research, Chinese Academy of {2., beijing 100101, China 2. institute of Tibetan Plateau research, Chinese Academy of {2., beijing 100085, China 3. Graduate School of Chinese Academy of {2., beijing 10003., China institute of geographical {2. and Natural {3. research Chinese Academy of Sciences Beijing China Graduate School of Chinese Academy of sciences Beijing China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China

Using five well-replicated Qilian juniper (Sabina przewalskii Kom.) tree-ring width index se- ries, monthly normalized difference vegetation index (NDVI) of grassland, and climatic data from 1982.to 2.01, the relationships between tree-ring width index, NDVI of grassland, and climatic data were analyzed firstly. Then, the relationship between tree-ring width index and NDVI of grassland was explored. The re- sults showed that: (1) Temperature and precipitation in June influenced tree-ring width index and NDVI of grassland deeply in Delingha. (2. There were sig- nificant relationships between five tree-ring width index series (DLH1-DLH5) and monthly NDVI of grassland from June to September, with the most significant relationship being between tree-ring width index series and NDVI of grassland in August. (3. The PC1 (the first principal component derived from DLH1-DLH5 series) exhibited good agreement with monthly NDVI of grassland in the grass growth sea- son (from June to September) and the averaged NDVI in the growth season, which was attributed to their common responses to water-supply limit in Delingha. This study may allow an increase in studying the past dynamics of grassland in Delingha in that the variation of grassland NDVI during the last millennium has been reconstructed from PC1.

关键词：圆柏祁连山 NDVI 草原年轮宽度指数

STUDY ON DEVELOPMENT STRATEGY OF SHIPPING CENTERS AND TRANSPORTATION NETWORKS IN THE YELLOW SEA RIM

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Chinese geographical Science 2003年第2期13卷 97-103页

作者： JIN Feng-jun (institute of geographic {2. and Natural {3. research, Chinese Acad emy of {2., beijing 100101, P.R. China) institute of geographic {2. and Natural {3. research Chinese Academy of Sciences Beijing 100101 P. R. China

It is very important to establish cooperative mechanism to guarantee allmembers to develop their e-conomies in the Yellow Sea Rim. In this paper, the development strategiesof shipping centers and transportation network are discussed based on economic globalizationtendency. The results argue that a united transportation network should be built in order to promotethe economic competition of Northeast Asia in the world. As a key component of the economiccooperation, a hierarchical shipping centers network should be established with Hong Kong, Shanghai,Pusan, Kobe, and Tokyo as cores. The authorities of China, Japan, R. 0. Korea and D. P. R. Koreashould make more efforts to build a set of cooperation institutions based on raising thetransportation efficiency.

关键词： the yellow sea rim shipping center transportation network hub-and-spoke system

Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai

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Science China Earth sciences 2005年第7期48卷 939-949页

作者： SHAO Xuemei1, HUANG Lei1, LIU Hongbin2. LIANG Eryuan1, FANG Xiuqi3.& WANG Lili1 1. institute of geographic {2. and Natural resources research, Chinese Academy of {2., beijing 100101, China 2. National Climate Center, beijing 100081, China 3. beijing Normal University, beijing 100875, China institute of geographic {2. Natural Resources Research Chinese Academy of Sciences Beijing 100101 China National Climate Center Beijing 100081 China beijing Normal University Beijing 100875 China

Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD152.—163. and 193.—2.01, whereas dry intervals in 142.—1519 and 163.—1741. In ad- dition, the magnitude in precipitation variation was lower before 143. with about 15 mm, but it increased to 3. mm during the period of 143. to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 2.st century.

关键词： northeastern part of the Qaidam Basin tree-ring width series of Qilian juniper precipitation reconstruction in 1000 years.

A study on environmental aridity over northern and southern to Qinling Mountains under climate warming

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Journal of geographical sciences 2001年第2期11卷 193-201页

作者： YAN Jun-ping~1, LIU Yan-sui~2.(1. College of Tourism and Environment, Shaanxi Normal University, Xi’an 710062. China 2. {3. of geographic {2. and Natural resources research, cas, beijing 100101, China) College of Tourism and Environment Shaanxi Normal University institute of geographic {2. and Natural {3. research CAS

Based on the data up to 1999 from hydroclimatological departments, this pape analyzes the climatic divide implications of the Qinling Mountains in regional response to the process of climate warming, due to which the grades of dryness/wetness (GDW) in 100 years show that the northern region has entered a drought period, while the southern is a humid period. In a course of ten years, the D-value of annual average air temperature over southern Shaanxi (the Hanjiang Valley) and the Central Shaanxi Plain (the Guanzhong Plain) has narrowed, i.e., the former with a slight change and the latter with rapid increase in temperature. Both regions were arid with the decrease in precipition D-value, namely the plain became warmer while the south was drier. The Qinling Mountains play a pronounced role in the climatic divide. The runoff coefficient (RC) of the Weihe River decreases synchronously with that of the Hanjiang due to climate warming. The RC of Weihe dropped from 0.2.in the 1950s to less than 0.1 in the 1990s. The Weihe Valley (the Guanzhong Plain) is practically an arid area due to shortage of water. The successive 0.5, 1.0°C temperature anomaly over China marks, perhaps, the improtant transition period in which the environment becomes more vulnerable than before. The study shows the obvious trend of environmental aridity, which is of help to the understanding of regional response to global climate change.

关键词： climate change aridity Qinling Mountains

Monitoring Dynamic Change of Land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

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Wuhan University Journal of Natural sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2. LIU Chuang1, 3.1. institute of geographic {2. and Natural resources research, Chinese Academy of {2., beijing 100101, China 2. Graduate University of Chinese Academy of {2., beijing 100049, China 3. College of resources Science and Technology, beijing Normal University, beijing 100875, China institute of geographic {2. and Natural {3. research Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of sciences Beijing China College of resources Science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993.the enhanced the-matic mapper plus (ETM+) image in 2.00,and the image with the charge-coupled device camera (CCD) on the China-Brazil earth resources satellite (CBERS) in 2.08 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993.to 2.08. There were 12.63..54 hm2.cropland de-creased between 1993.and 2.00,and 8 2.7.6 hm2.cropland de-creased between 2.00 and 2.08. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world resources {2.es.

关键词： land cover the China-Brazil earth resources satellite (CBERS) support vector machine (SVM) change detection

PLS path model building:A multivariate approach to land price studies-A case study in beijing

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Progress in Natural Science:Materials International 2009年第11期19卷 1643-1649页

作者： Wenjie Wu~(a,b),Wenzhong Zhang~(a,*) a institute of geographic {2. and Natural {3. research,cas,beijing 100101,China b Graduate University of Chinese Academy of {2.,beijing 100049,China institute of geographic {2. and Natural {3. research CAS Beijing 100101 China Graduate University of Chinese Academy of sciences Beijing 100049 China

Previous studies have revealed that statistical methods can be used to analyze land-leasing parcel ***,the conventional statistical methods used in land analysis have some limitations,especially in cases of limited observational *** this paper,with the help of geographic information system(GIS) techniques,a partial least squares(PLS) path model is applied to study the relationship between residential land prices and various determinants through a case study of {3. in *** a preliminary analysis,four latent variables are selected:accessibility of the workplace center,livability,traffic,and environment *** results show that the observation variables have a strong explanatory power for their corresponding latent variables,and the four latent variables have varying impacts on residential land *** the latent variables,accessibility to the workplace center has the strongest impact on the residential land price.

关键词： Land PLS path model GIS beijing

Rocky Land Desertification and its Driving Forces in the Karst Areas of Rural Guangxi,Southwest China

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Journal of Mountain Science 2008年第4期5卷 350-357页

作者： LIU Yansui WANG Jieyong DENG Xiangzheng institute of geographic {2. and Natural {3. research Chinese Academy of Science Beijing 100101 China institute of geographic {2. and Natural {3. research Chinese Academy of Science Beijing loolo~ ChinaGraduate University of Chinese Academy of Sciences Beijing 100039 China

With a subtropical climate,Guangxi Zhuang Autonomous Region has a typical karst *** desertification has become a serious environmental issue due to its high vulnerability caused by the joint effect of natural settings and human activities,because of which its eco-environment has been deteriorated in recent years,and farmland has been disappearing sharply at the same ***,in turn,has exacerbated the poverty level in the rural areas of the *** this study,we monitored the spatial distribution of rocky land desertification and its temporal evolution using Landsat TM/ETM images of 1985,1995,2.00 and *** also analyzed the driving forces of the desertification and its *** constructing regression models by using all the relevant variables and considering the lagged effects as well as fixed effects,we quantified the exact role of different factors causing rocky land desertification in the study area with some new *** new findings in this study are greatly helpful for preserving,restoring and reconstructing the degraded mountain environment in Guangxi and other karst areas in Southwest China,and also for alleviating poverty in the rural areas in the future.

关键词： Rocky land desertification karstmountain area rural poverty driving force Guangxi Southwest China

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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Science China(Technological sciences) 2004年第z1期47卷 60-71页

作者： WANG Zhonggen1, ZHENG Hongxing1, LIU Changming1, , WU Xianfeng2.2.& ZHAO Weimin3.1. Key Laboratory of Water Cycle & Related Land Surface Processes, institute of {3. Science and Natural {2. research, Chinese Academy of sciences, beijing 100101, China 2. institute of Environmental Science, beijing Normal University, beijing 100875, China 3. Water {2. Conservation Committee of Yellow River, Zhengzhou 450003. China Chinese Acad Sci Key Lab Water Cycle & Related Land Surface Proc Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China beijing Normal Univ Inst Environm Sci Beijing 100875 Peoples R China Water resources Conservat Comm Yellow River Zhengzhou 450003 Peoples R China

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, Yellow River Basin.