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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, chinese academy of sciences, beijing 100101, China institute of forestry science, chinese academy of forestry science, beijing 100091, China Research Center for Eco-Environment sciences, chinese academy of sciences, beijing 100085, China Computing institute of science and Engineering, North China Electric Power University, beijing 102206, 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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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, chinese 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 2020. 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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Analysis of forest backscattering characteristics based on polarization coherence tomography

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science China(Technological sciences) 2010年第S1期53卷 166-175页

作者： LUO HuanMin 1,LI XiaoWen 1,2,CHEN ErXue 3,CHENG Jian 4.& CAO ChunXiang 21 institute of Geo-Spatial Information science and Technology,University of Electronic science and Technology of China,Chengdu 610054.China 2 State Key Laboratory of Remote Sensing science,Jointly Sponsored by the institute of Remote Sensing Applications of chinese academy of sciences and beijing Normal University,beijing 100101,China 3institute of Forest Resources Information Technique of chinese academy of forestry,beijing 100091,China 4.School of Electronic Engineering,University of Electronic science and Technology of China,Chengdu 610054.China State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China beijing Normal Univ Beijing 100101 Peoples R China Univ Elect Sci & Technol China Inst Geospatial Informat Sci & Technol Chengdu 610054 Peoples R China chinese Acad forestry Inst Forest Resources Informat Tech Beijing 100091 Peoples R China Univ Elect Sci & Technol China Sch Elect Engn Chengdu 610054 Peoples R China

It is difficult to make an inventory of vertical profiles of forest structure parameters in field ***,analysis and understanding of forest backscattering characteristics contribute to estimation and detection of forest vertical structure because of the close relationships between backscattering characteristics and structure *** vertical structure function in the complex interferometric coherence definition,which represents the vertical variation of microwave scattering with the penetration depth at a point in the 2-D radar image and can be used to analyze the forest backscattering characteristics,can be reconstructed from polarization coherence tomography(PCT).Based on PCT,the paper analyzes the forest backscattering characteristics and explores the inherent relationship between the result of PCT and the forest structure parameters from numerical simulation of Random Volume over Ground model(RVoG),Polarimetric SAR interferometry(PolInSAR)simulation of forest scene and PolInSAR data at L-band of the test site ***,the effects of the extinction coefficient and surface-to-volume scattering ratio in RVoG model on vertical backscattering characteristics are analyzed by means of numerical ***,by applying PCT to L-band POLInSAR simulations of forest scene,different variations of vertical backscattering due to different extinction coefficients and the ratios of surface-to-volume scattering resulting from different polarizations,forest types and densities are displayed and *** a concept of relative average backscattering intensity is presented,and the factors which affect its vertical distribution are also *** results show that there is high sensitivity of the vertical distribution of forest relative average backscattering intensity to the polarization,forest type and ***,based on repeat pass DLR E-SAR L-band airborne POLInSAR data,the capability of PCT technology for detection

关键词： backscattering characteristic POLInSAR PCT vertical structure function

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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 academy of forestry,{4., China institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, China Departmet of forestry and Natural Resources, Purdue University, West Lafayette, IN 4.907, USA Graduate University, chinese academy 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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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 {4. of Remote Sensing Applications,chinese academy of sciences and beijing Normal University,beijing 100101,China 3 {4. 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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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 4.0716, 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 boundary of palaearctic and oriental realms in western China

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Progress in Natural science:Materials International 2008年第7期18卷 833-841页

作者： Ling Chen a,b,c, Yanling Songd,*, Shufang Xu e a Northwest institute of Plateau Biology, chinese academy of sciences, Xining 810001, China b Graduate University of the chinese academy of sciences, beijing 100039, China c National science Foundation of China, beijing 100085, China d institute of Zoology, chinese academy of sciences, beijing 100101, China e beijing academy of Agriculture and forestry sciences, beijing 100097, China Northwest institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China Graduate University of the chinese academy of sciences Beijing 100039 China National science Foundation of China Beijing 100085 China institute of Zoology Chinese Academy of Sciences Beijing 100101 China beijing academy of Agriculture and forestry sciences Beijing 100097 China

In the world-wide zoogeographic division, there has been no consentaneous understanding about the delimitation between palaearctic and oriental realms in western China. In this study, we will discuss the division based on amphibian distribution in Shaanxi, Gansu, Sichuan, Yunnan, and Tibet according to species coefficient similarity between each zoogeographic province. The results show that the northern border lies from Qinling Mountains–Feng Xian (Shaanxi)–Debu (Gansu)–Aba (Sichuan)–Batang–Bomi (Tibet), to Linzhi districts, and the southern border is from Taibai–Feng Xian in Shaanxi–Wen Xian (Gansu)–Songpan–Kangding–Daocheng (Sichuan), to Zhongdian–Gongshan in Yunnan, and westward to Motuo and Bomi district in Tibet.

关键词： Amphibian Zoogeography Palaearctic Oriental Hengduan Mt.

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Expression characteristics of GFP driven by NAC1 promoter and its responses to auxin and gibberellin

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Progress in Natural science:Materials International 2006年第7期16卷 701-705页

作者： WANG Youhua, DUAN Liusheng, LU Mengzhu, LI Zhaohu, WANG Minjie and ZHAI Zhixi ( State Key Laboratory of Plant Physiology and Biochemistry, College of Agronomy and Biotechnology, China Agricultural University, beijing 100094. China The forestry institute, China forestry {4., beijing 100091, China) [a]State Key Laboratory of Plant Physiology and Biochemistry College of Agronomy and Biotechnology China Agricultural University Beijing China [b]The forestry institute China Forestry Academy Beijing China

A 1050 bp fragment upstream transcription start site of a transcription factor gene NACl in Arabidopsis thaliana was amplified and cloned into plasmid pRD4.0 to construct a green fluorescent protein(GFP) fusion system under the control of NACl promoter. Plasmids were introduced into tobacco by Agrobacterium -mediated method to regenerate plants with NAC1-GFP gene, and expression pattern of NAC1-GFP and its responses to auxin and gibberellin (GA) were observed. GFP was found to accumulate specifically in root, and was detected after treatment of auxin, N-1-Naphthylphthalamic acid (NPA, an auxin antagonist) or GA3. It was indicated that the expression of GFP driven by NACl promoter was induced not only by auxin but also by GAs, suggesting that NACl mediated both the auxin signaling and the GAs signaling involved in lateral roots development.

关键词： auxin gibberellin NAC1 GFP.

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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 academy 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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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 academy of sciences, {4. 100101, China 2 Kunming institute of Zoology, chinese academy of sciences, Yunnan, 650223, China 3 The Research institute of Forest Ecology, Environment and Protection, The chinese academy of forestry, 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 27 species of the most significant invasive alien insects in the world (through November, 2005), 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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