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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 sciences and Natural resources Research, Chinese Academy of sciences, Beijing 100101, China 2. Graduate {3. of Chinese Academy of sciences, Beijing 100049, China 3. College of resources science and Technology, Beijing Normal {3., Beijing 100875, China Institute of Geographic sciences and Natural resources 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 researches.

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

The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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science China Earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2. CAI Qiangguo1, YUE Zhongqi3. LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic sciences and Natural resources Re-search, Chinese Academy of sciences, Beijing 100101, China 2. Institute of Forestry, Chinese Academy of Forestry sciences, Beijing 100091, China 3. Department of Civil Engineering, university of Hong Kong, Hong Kong, China 4. Eco-environmental Research Center, Chinese Academy of sciences, Beijing 100085, China 5. College of resources and Environment, Southwest Agricultural university, chongqing 400716, China Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of Forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. Department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. College of resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 53. mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2. it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 3.%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

Run off-on-out method and models for soil infiltrability on hill-slope under rainfall conditions

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science China Earth sciences 2006年第2期49卷 193-201页

作者： LEI Tingwu1,2. LIU Han1, PAN Yinghua3. ZHAO Jun2. ZHAO Shiwei2.& YANG Yonghui2.1. The Key Laboratory of Modern Precision Agriculture System Integration Research, College of Hydraulic and Civil Engineer-ing, China Agricultural university, Beijing 100083. China 2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Yangling 712.00, China 3. Geographic and resources Management College, Yantai Normal university, Yantai 2.402., China 1. The Key Laboratory of Modern Precision Agriculture System Integration Research College of Hydraulic and Civil Engineering China Agricultural University Beijing 100083 China 2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Yangling 712100 China 3. Geographic and resources Management College Yantai Normal University Yantai 264025 China

The soil infiltrability of hill-slope is important to such studies andpractices as hydrological process, crop water supply, irrigation practices, and soil erosion. A newmethod for measuring soil infiltrability on hill-slope under rainfall condition with run off-on-outwas advanced. Based on water (mass) balance, the mathematic models for soil infiltrability estimatedfrom the advances of runoff on soil surface and the water running out of the slope were *** of 2.cases were conducted. Case Ⅰ was done under a rainfall intensity of 2. mm/h, at aslope gradient of about 0° with a runoff/on length (area) ratio of 1 : 1. Case Ⅱ was under arainfall intensity of 60 mm/h and a slope of 2.° with a runoff/on length (area) ratio of 1 : *** ring method was also used to measure the infiltrability for comparison purposes. Theexperiments were done with soil moisture of 10%. Required data were collected from laboratoryexperiments. The infiltrability curves were computed from the experimental data. The resultsindicate that the method can well conceptually represent the transient infiltrability process, withcapability to simulate the very high initial soil infiltrability. The rationalities of the methodand the models were validated. The errors of the method for the two cases were 1.82./1.3.% and4.49%/3.52.% (Experimental/Model) respectively, as estimated by comparing the rainfall amount withthe infiltrated volume, to demonstrate the accuracy of the method. The transient and steadyinfiltrability measured with double ring was much lower than those with this new method, due towater supply limit and soil aggregates breaking down at initial infiltration stage. The method canovercome the short backs of the traditional sprinkler method and double ring method for soilinfil-traility. It can be used to measure the infiltrability of sloped surface underrainfall-runoff-erosion conditions, in the related studies.

关键词： Infiltrability, runoff-on-out, rainfall, sloped surface, model.

Regional differences and determinants of built-up area expansion in China

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science China Earth sciences 2007年第12期50卷 1835-1843页

作者： HUANG JiKun1,2.ZHU LiFen3.1 & DENG XiangZheng1,2.1 Center for Chinese Agricultural Policy,Chinese Academy of sciences,Beijing 100101,China 2.Institute of Geographic sciences and Natural {2. Research,Chinese Academy of sciences,Beijing 100101,China 3.Research Center of the Economy of the Upper Reaches of the Yangtze River,chongqing Technology and Business university,chongqing 400067,China 1. Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China 2. Institute of Geographic sciences and Natural resources Research Chinese Academy of Sciences Beijing 100101 China 3. Research Center of the Economy of the Upper Reaches of the Yangtze River Chongqing Technology and Business University Chongqing 400067 China

Based on remote sensing data on land use provided by the Chinese Academy of sciences and socio-economic data collected by the authors,this paper analyzes the trends and regional differences in built-up area(BUA) expansion in China from the late 1980s to 2.00,and empirically estimates the major determinants of BUA expansion in different regions in 1996―*** 1989―2.00,although China's overall BUA expansion accelerated,the trends differed significantly among *** expansion in the central and western regions accelerated significantly,but it slowed down considerably in the east-ern *** estimation results from our econometric analysis reveal that BUA expansion in the eastern region reached a period when economic growth had no further significant impact on per capita BUA,the land utilization in this region has become more intensive with further expansion of the *** the central and western regions,the BUA has expanded remarkably due to the relatively more flexible land development policies and the relatively cheap land ***,as the econ-omy continues to grow rapidly,policies relating to BUA expansion and cultivated land reductions may face more serious challenges in the central and western regions.

关键词： built-up area, land use, regional difference, determinants, China

Synthesis and Characterization of Ibuprofen-Rectorite Composites by Solution Intercalation Method

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Journal of Wuhan university of Technology(Materials science) 2009年第4期24卷 654-657页

作者：王慧燕 Hospital Wuhan University of Teehnology

The ibuprofen-rectorite composites were prepared by the solution intercalation method using ibuprofen and rectorite as raw materials, and were characterized by X-ray diffraction （XRD） analysis, Fourier transform infrared analysis and scanning electron microscopy （SEM）. The experimental results show that the ibuprofen is intercalated into the interlayer spaces of rectorite. The values of the （001） peaks of the ibuprofen-rectorite composite are larger than that of Na-rectorite and reach the largest when the reaction time and ibuprofen amount is 2.h and 0.3. g, respectively. The layered structure of Na-rectorite is destroyed to some extent with the intercalation of ibuprofen into the interlayer space in the structure of Na-rectorite. A part of ibuprofen in the ibuprofen Na-rectorite covers on the surface of Na-rectorite besides some ibuprofen enters into the interlayer space.

关键词： ibuprofen rectorite solution intercalation composites clay

Semantic-aware Learning resources Management

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Semantic-aware Learning Resources Management

Flooding 1990s along the Yangtze River, has it concern of global warming?

第三届教学管理与课程建设学术会议

作者： Feng Jiang 1, 2., Min Gao 1, 1 School of Software Engineering, chongqing university, chongqing, {2., P. R. China 2.chongqing Radio and TV university, chongqing, 400052. P. R. China

Learning object metadata (LOM) facilitates the indexing and searching of learning resources. This paper reviews the definitions of learning object and the metadata-based learning objects organization at first. It then analyzes the metadata standards, relationships, and their limitation in semantic-awareness capability from Dublin Core, IEEE LTSC, and SCORM. To solve the issue, the paper incorporates ontology and logic to the architecture of semantic learning content, which provides formal descriptions for the concepts, terms, and relationships of learning resources. It also proposes a three-level framework for the presentation of knowledge units, meta knowledge, and domain knowledge. Finally, it presents an interoperation model for learning resource management. The architecture, framework, and model help select suitable objects from heterogeneous learning content repositories.

关键词： Learning object Learning object metadata Semantics

来源： cnki会议评论

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Journal of Geographical sciences 2001年第1期11卷 43-52页

作者： GONG Dao-yi1, ZHU Jin-hong2. WANG Shao-wu2.(1. Key Laboratory of environmental Change and Natural Disaster, Institute of {3. {2., Beijing Normal {3., Beijing 100875, China 2. Department of Geophysics, Peking {3., Beijing 100871, Key Laboratory of environmental Change and Natural Disaster Institute of Resources Science Beijing Normal University Beijing China Department of Geophysics Peking University Beijing China

There were a series of severe floods along the middle to lower reaches of the Yangtze River (Changjiang River) in China during the 1990s. The extensive summer (June, July and August) precipitation is mostly responsible for the flooding. The summer rainfall in the 1980s and the 1990s is much higher than that in the previous 3.decades. The means for 1990–1999 is +87.62.mm above normal, marked the 1990s the wettest decade since the 1950s. Six stations with a time span of 1880–1999 are selected to establish century-long rainfall series. This series also shows that the 1990s is the wettest decade during the last 12. years. In the wettest 12.years, four occurred in the 1990s (1991, 1996, 1998 and 1999). Both global and China’s temperature show there is a relative lower air temperature during the 1960–1970s, and a rapid warming in the 1980–1990s. Comparisons of rainfall between 1960–1979 and 1980–1999 show there are dramatic changes. In the cold period 1960–1979, the summer rainfall along the Yangtze River is 3.8 % to 4.7 % below the normal, during the warm period 1980–1999, over 8.4 % to 18.2.% of summer rainfall occurs. Over the whole eastern China, the summer rainfall shows opposite spatial patterns from the 1960–1970s to 1980–1990s. The consistent trend toward more rainfall with global warming is also presented by the greenhouse scenario modeling. A millennial Drought/flood Index for the middle to lower reaches of the Yangtze River showed that although the surplus summer rainfall in the 1990s is the severest during the past 150 years, it is not outstanding in the context of past millennium. Power spectra of the Drought/flood Index show significant interdecadal periods at 3..3.and 11.8 years. Thus, both the natural interdecadal variations and the global warming may play important roles in the frequent floods witnessed during the last two decades.

关键词： summer rainfall Yangtze River global warming interdecadal variation

Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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science China Earth sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2. JIN ZhangDong1 & ZHANG Fei3.1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075, China 2.Graduate {3. of the Chinese Academy of sciences, Beijing 100049, China 3.College of {3. and environmental science, Nanjing Agricultural {3., Nanjing 2.0095, China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China Graduate university of the Chinese Academy of sciences Beijing 100049 China College of resources and Env

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest China. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2. the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3. the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

N_2. emissions from agricultural soils in the North China Plain: the effect of chemical nitrogen fertilizer and organic manure

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Journal of environmental sciences 2000年第4期12卷 463-468页

作者： DONG Yun\|she 1,2.3., Dieter Scharffe 2. Manfred Domroes 3. QI Yu chun 1, ZHANG Shen 1 (1. Institute of Geographic sciences and Natural {3. Research, Chinese Academy of sciences, Beijing 100101, China E\|mail: dongys@*** 2. M 中科院地理科学与资源所北京 1 0 0 1 0 Max- Planck-Institute of Chemistry 德国 Mainz 550 2 0 Mainz university 德国 Mainz 550 99

An enclosed chamber technique was used to measure N 2. emissions from intensively agricultural soils of the North China Plain during the periods of 1995—1996 and 1997—1998, to reflect distinct components of winter wheat and summer maize growing seasons. The results showed that the continuous application of fertilizer in agricultural soils increased N\-2. emissions by a factor of 2..1—2..1, the calculated annual chemical N fertilizer\|transformed N\-2.\|N emissions was 0.67%. Our results indicated that the application of organic manure also had a significant influence on soil N 2. emissions, which combined with the use of chemical N increased about 2.% in a year. It was calculated that there were about 0.11% N of organic manure transformed as N 2. N. Annual mean N 2. emission from our study area of fertilized soils was estimated to be 57.1 μgN 2./(m 2.h). A weak correlation was also found between N 2. emissions and soil available nitrogen content NH + 4.

关键词： N_2. emissions the North China Plain agricultural soils chemical nitrogen organic manure