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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,{5. institute of forestry Science, {2. Academy of forestry Science, beijing 100091,{5. Research Center for Eco-Environment sciences, {2. Academy of sciences, beijing 100085.{5. Computing institute of Science and Engineering, North{5. Electric Power University, beijing 102.06,{5. 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 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, {5. 100101, china 2. institute of forestry, {2. 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, {5. 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 5.0 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 D5. (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 (D5., 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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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 {2., beijing 100091, china institute of Applied Ecology, chinese Academy of sciences, Shenyang 110016, china Departmet of {2. and Natural Resources, Purdue University, West Lafayette, IN 47907, USA Graduate University, chinese Academy of sciences, {12. 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 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,{5.

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 {2. 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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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 {2., beijing 100101,{5. 2.Kunming institute of Zoology, chinese Academy of {2., Yunnan, 65.2.3,{5. 3 The Research institute of Forest Ecology, Environment and Protection, The chinese Academy of forestry,{12.,{5. 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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Carbon isotope ratios of C_(4) plants in loess areas of North china

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Science china Earth sciences 2006年第1期49卷 97-102页

作者： WANG Guoan1,2.3, HAN Jiamao 2. ZHOU Liping3, XIONG Xiaogang4, TAN Ming2. WU Zhenhai5.& PENG Jun6 1. Department of Plant Nutrition, china Agricultural University, beijing 100094, china 2. institute of Geology and Geophysics, chinese Academy of sciences, beijing 10002., china 3. College of Environmental sciences, MOE Laboratory for Earth Surface Processes, Peking University, beijing 100871, china 4. institute of Botany, chinese Academy of sciences, beijing 100093, china 5. Northwest Sci-Tech University of Agriculture and forestry, Yangling 712.00, china 6. Network Center, china Agricultural University, beijing 100094, china 1. Department of Plant Nutrition China Agricultural University Beijing 100094 China 2. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. College of Environmental sciences MOE Laboratory for Earth Surface Processes Peking University Beijing 100871 China 4. institute of Botany Chinese Academy of Sciences Beijing 100093 China 5. Northwest Sci-Tech University of Agriculture and forestry Yangling 712100 China 6. Network Center China Agricultural University Beijing 100094 China

Carbon isotope ratios (δ^(13)C) of 89 C_4 plant samples were determined fromthe loess area in North china. δ^(13)C values vary between -10.5.er thousand and -14.6per thousandwith a mean of -12.6per thousand. Along a precipitation gradient from the semi-moist area to thesemiarid area, then to the arid area, the δ^(13)C values of C_4 plants show a slight decreasingtrend. The δ^(13)C values of C_4 plants in the dry season are found lower than those in the wetseason. These trends are opposite to those observed for C_3 species.

关键词： C4 plants, carbon isotope ratios, loess area.

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^(40)Ar/^(39)Ar dating of shear deformation of the Xianshuihe fault zone in west Sichuan and its tectonic significance

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Science china Earth sciences 2004年第9期47卷 794-803页

作者： ZHANG Yueqiao1, CHEN Wen2. 3 & YANG Nong1 1. institute of Geomechanics, chinese Academy of Geological {2., beijing 100081,{5. 2. institute of Geology, chinese Academy of Geological {2., beijing 100037,{5. 3. institute of Geology and Geophysics, chinese Academy of {2., beijing 10002.,{5. institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Based on field geological survey, structural measurements and classical Ar/Ar dating of mica, biotite and K-feldspar, we obtain cooling ages for Miocene left-lateral shear along the Xianshuihe fault zone. The results document two thermal events during the sinistral shear. The early event (12.10 Ma) corresponds to rapid cooling of the Zheduoshan granitic massif from above 700℃ to below 35.℃. The late event (5.3.5.Ma) corresponds to cooling of granites intruded along the eastern side of the fault zone. These dating results provide important thermochronological constraint on the timing of late Cenozoic eastward extrusion of the Chuan-Dian Block in the SE Tibetan margin.

关键词： Xianshuihe fault zone, Zheduoshan granitic massif, sinistral shear deformation, 40Ar/39Ar dating, late Cenozoic.

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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. {2. of Computing Technology, chinese Academy of sciences, beijing 100080, china 3. Graduate School of the chinese 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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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 Academy of {2. and Ministry of Water Resources, Northwest Agriculture and forestry University, Yangling 712.00, china 2.institute of Geographical {2. and Natural Resources Research, chinese Academy of {2., 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 > 5. mm was rarely presented. The covers of rock fragment at different positions were markedly related to the quantities of rock fragment 2.5. 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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