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Thresholds of geographic environmental elements in sediment yield of drainage basins

Science China Earth sciences 2005年第2期48卷 230-240页

作者： CHEN Hao, ZHOU Jinxing, CAI Qiangguo, LU Zhongchen & LI Zhongyan institute of Geographic sciences and Natural Resources Research,{2. academy of sciences, beijing 100101, China institute of forestry Science,{2. academy of forestry Science, beijing 100091, China Research Center for Eco-Environment sciences,{2. academy of sciences, beijing 100085, China Computing institute of Science and Engineering, North China Electric Power University, beijing 102.06, China 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. institute of forestry Science Chinese Academy of Forestry Science 100091 Beijing China 3. Research Center for Eco-Environment sciences Chinese Academy of Sciences 100085 Beijing China 4. Computing institute of Science and Engineering North China Electric Power University 102206 Beijing China

Threshold of environmental elements in drainage basin sediment yield refers to, under effect of climate, underlying surface and human activity, a turning point of abrupt changes in drainage sediment yield related to environmental element characteristics. Previous studies on threshold of sediment yield of relevant drainage basins were mainly concentrated on impact of natural zones with a few researches on impact of other environmental elements. Particularly studies on compound environmental element threshold in drainage basin sediment yield remain blank today. Studies indicate that sediment yield in drainage basins is affected by compound interactions and complex actions. Based on single element analysis, the present paper gives quantitatively compound threshold of environmental elements affecting sediment yield of the drainage basin between Hekouzhen and Tongguan in the middle Yellow River by the method of multi-variant, polynomial formula regression analysis.

关键词： middle Yellow River, environmental element, sediment, sediment delivery mudule, threshold.

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Formal Verification under Unknown Constraints

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Wuhan University Journal of Natural sciences 2005年第1期10卷 43-46页

作者： LI Guang-hui 1,2.3 , LI Xiao-wei 2.31. School of Information Engineering, Zhejiang forestry College, Hangzhou 311300, Zhejiang, China 2. institute of Computing Technology,{2. academy of sciences, beijing 100080, China 3. Graduate School of the{2. academy of sciences, beijing 100039, China School of Information Engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

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Threat and management strategies of potentially invasive insects in China

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Science China(Life sciences) 2009年第10期52卷 903-910页

作者： ZHANG RunZhi1, ZHANG YaPing2.& JIANG YouXu3 1 State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, institute of Zoology, chinese{2. of sciences, beijing 100101, China 2.Kunming institute of Zoology, chinese{2. of sciences, Yunnan, 6502.3, China 3 The Research institute of Forest Ecology, Environment and Protection, The chinese{2. of {12., beijing 100091, China State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture Institute of Zoology Chinese Academy of Sciences Beijing 100101 China Kunming institute of Zoology Chinese Academy of Sciences Yunnan 650223 China The Research institute of Forest Ecology Environment and Protection The Chinese Academy of Forestry Beijing 100091 China

The Global Invasive Species Database, GISD, comprises 2. species of the most significant invasive alien insects in the world (through November, 2.05), 6 of which are originally native to China, 11 are established in China, and 10 have a potential invasion threat to China. This paper discusses these species in terms of distribution, harmfulness and dispersal ways, and finds that: (i) Information re-garding invasive insects in the GISD remains inadequate. Such harmful invasive species as Opogona sacchari (Bojer), Oracella acuta (Lobdell), and Dendroctonus valens LeConte are not included. (ii) Ten species of invasive insects, particularly Lasius neglectus Van Loon and Linepithema humile (Mayr) which become established in areas near China, have the potential to become established in China. (iii) Special attention should be paid to species from Asia and the Americas because of their greater likeli-hood of becoming established in China. Finally, some management strategies including legislation, quarantine, early warning, prevention and control are suggested.

关键词： biological invasions invasive species insect China

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Detection of the urban heat island in beijing using HJ-1B satellite imagery

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Science China Earth sciences 2010年第S1期53卷 67-73页

作者： YANG Jun1,GONG Peng2.ZHOU JinXing3,HUANG HuaBing2.& WANG Lei2.1 Key Laboratory of Silviculture and Conservation,Ministry of Education,beijing forestry University,beijing 100083,China 2.State Key Laboratory of Remote Sensing Science,jointly sponsored by the institute of Remote Sensing Applications,chinese academy of sciences and beijing Normal University,beijing 100101,China 3 institute of Desertification Studies,chinese academy of forestry,beijing 100091 China 1. Key Laboratory of Silviculture and Conservation Ministry of Education Beijing Forestry University Beijing 100083 China2. State Key Laboratory of Remote Sensing Science jointly sponsored by the Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China3. Institute of Desertification Studies Chinese Academy of Forestry Beijing 100091 China

Satellite images are used extensively in studying the urban heat island(UHI) *** evaluated the suitability of thermal infrared(TIR) data from the HJ-1B satellite for detecting UHI using a case study in *** modified algorithms for retrieving the land surface temperature(LST) from HJ-1B data were *** results were compared with LST images derived from a Landsat TM thermal band and the MODIS LST *** spatial pattern of UHI generated using HJ-1B data matched well with that produced using TM and MODIS *** the two algorithms,the mono-window algorithm performed better but further tests are *** more frequent coverage than TM and higher spatial resolution than MODIS,the HJ-1B TIR data present a unique opportunity to study thermal environments in cities in China and neighboring countries.

关键词： surface temperature NDVI mono-window algorithm single-channel algorithm

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Digital forestry research in China

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Science China(Technological sciences) 2006年第z1期49卷 1-8页

作者： TANG Shouzheng, TANG Una, Guofan Shao & DAI Limin Research institute of Resource Information Techniques, chinese{2. of forestry, beijing 100091, China institute of Applied Ecology, chinese{2. of sciences, Shenyang 110016, China Departmet of forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA Graduate University, chinese{2. of sciences, beijing 100101, China Research institute of Resource Information Techniques Chinese Academy of Forestry Beijing 100091 China institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Department of forestry Natural Resources Purdue University West Lafayette IN 47907 USA Graduate University Chinese Academy of Sciences Beijing 100101 China

Digital forestry as a concept was developed after the Digital Earth program. The chinese scientists were not only among the pioneers who first proposed the concept of Digital forestry, but also contributed a lot to the development of Digital forestry. Digital forestry is a digital framework to maintain forest planting, management, using, and protect. The synergetic use of computationally-intensive quantitative methods together with information technologies is the most important foundation for the development of Digital forestry. Under this situation, the experience of Digital forestry development in China is relatively rich. A number of academicians, scholars, and professional administrators were involved in discussing the Digital forestry Construction Scheme. The Project of Digital forestry Practicability approved by the State forestry Administration is a major instance in developing Digital forestry standard and key techniques. By introducing a case study of Digital forestry, this paper reviews the concept of Digital forestry, the way turning traditional forestry into Digital forestry, and the future development of Digital forestry.

关键词： Digital Forest, Digital Earth, Digital forestry standard, Digital forestry techniques.

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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,{2. 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,{2. 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 530 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 30%.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.

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The global climate change and forest prediction in China

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Journal of Environmental sciences 1994年第3期6卷 310-321页

作者： Jiang Youxuforestry institute,{2. academy of forestry, beijing 100091, China

The climate change prediction in China based on OCU model as well as summary ana-lyses of GFDL, GISS, NCAR, OCU and UKMO models are used for discussing the approaches topredict the response of the forest in China under double concentration of atmospheric carbondioxide after about 2.2.. The growth, production and distribution boundary of chinese fir(Cunninghamia lanceolata), the tree composition and their growth in cold temperete Daxingan Moun-tain region, and potential forest zones in China are discussed in this paper as example.

关键词： global climate change forest in China prediction.

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Spatial distribution of surface rock fragment on hillslopes in a small catchment in wind-water erosion crisscross region of the Loess Plateau

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Science China Earth sciences 2008年第6期51卷 862-870页

作者： ZHU YuanJun1,2.& SHAO MingAn1 1 institute of Soil and Water Conservation, chinese{2. of sciences and Ministry of Water Resources, Northwest Agriculture and forestry University, Yangling 712.00, China 2.institute of Geographical sciences and Natural Resources Research, chinese{2. of sciences, beijing 100101, China 1. institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Northwest Agriculture and Forestry University Yangling 712100 China 2. institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

The cover and size distributions of surface rock fragment in hillslopes were investigated by using digital photographing and treating technique in a small catchment in wind-water erosion crisscross region of the Loess Plateau. The results indicated that the maximal cover of rock fragment was pre-sented at mid-position in steep hillslope. Rock fragment presented a general decreasing-trend along the hillslope in gentle hillslope. Rock fragment cover was positively related to gradient, rock fragment size decreased generally along the hillslope, and the size reduced with the gradient. The mean size of rock fragment was at a range of 6―2. mm in the steep hillslope, rock fragment size > 50 mm was rarely presented. The covers of rock fragment at different positions were markedly related to the quantities of rock fragment 2.50 mm accounted for 60% or more of the total area, dominating the distribution of rock fragment in the hillslopes.

关键词： wind-water erosion crisscross region of the Loess Plateau small catchment hillslope surface rock fragment cover and size

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Spatial heterogeneity of the driving forces of cropland change in China

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Science China Earth sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2. WANG Jinfeng1, LIU Mingliang4,1 & MENG Bin1,2.3 1. institute of Geographic sciences and Natural Resources Research,{2. academy of sciences, beijing 100101, China 2. Graduate School of the{2. academy of sciences, beijing 100039, China 3. College of Arts and sciences of beijing Union University, beijing 100083, China 4. School of forestry and Wildlife sciences, Auburn University, Auburn, Alabama, AL36849, USA 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the chinese academy of{2. 100039 Beijing China 3. School of forestry and Wildlife sciences Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of beijing Union University 100083 Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2.00 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in China. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of China, natural condition changes and geographical background were the main constraints and drivers, while in Eastern China, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in China recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, China.

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A study on the early-warning technique concerning debris flow disasters

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Journal of Geographical sciences 2002年第3期12卷 363-370页

作者： ZHOU Jinxing, WANG Lixian, XIE Baoyuan, FEI Shimin, WANG Xilin (1. Inst. of forestry Research, chinese{2. of forestry Science, beijing 100091, China 2. College of Resource & Environment, beijing forestry University, beijing 100083, China) Inst of Forestry Research Chinese Academy of Forestry Science 北京 100091 College of Resource & Environment Beijing Forestry University 北京 100083

According to the principle of the eruption of debris flows, the new torrent classification techniques are brought forward. The torrent there can be divided into 4 types such as the debris flow torrent with high destructive strength, the debris flow torrent, high sand-carrying capacity flush flood torrent and common flush flood by the techniques. In this paper, the classification indices system and the quantitative rating methods are presented. Based on torrent classification, debris flow torrent hazard zone mapping techniques by which the debris flow disaster early-warning object can be ascertained accurately are identified. The key techniques of building the debris flow disaster neural network (NN) real time forecasting model are given detailed explanations in this paper, including the determination of neural node at the input layer, the output layer and the implicit layer, the construction of knowledge source and the initial weight value and so on. With this technique, the debris flow disaster real-time forecasting neural network model is built according to the rainfall features of the historical debris flow disasters, which includes multiple rain factors such as rainfall of the disaster day, the rainfall of 15 days before the disaster day, the maximal rate of rainfall in one hour and ten minutes. It can forecast the probability, critical rainfall of eruption of the debris flows, through the real-time rainfall monitoring or weather forecasting. Based on the torrent classification and hazard zone mapping, combined with rainfall monitoring in the rainy season and real-time forecasting models, the debris flow disaster early-warning system is built. In this system, the GIS technique, the advanced international software and hardware are applied, which makes the system’s performance steady with good expansibility. The system is a visual information system that serves management and decision-making, which can facilitate timely inspect of the variation of the torrent type

关键词： debris flows disaster early-warning technique torrent classification mapping of the hazard zones

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