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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 Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China institute of forestry Chinese Academy of Forestry Sciences Beijing China Department of Civil Engineering University of Hong Kong Hong Kong China Eco-environmental Research Center Chinese Academy of Sciences Beijing China College of Resources and Environment Southwest Agricultural University 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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Thresholds of geographic environmental elements in sediment yield of drainage basins

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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,{12., 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 institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China institute of forestry Science Chinese Academy of Forestry Science Beijing China Research Center for Eco-Environment sciences Chinese Academy of Sciences Beijing China Computing institute of Science and Engineering North China Electric Power University 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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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 China institute of Applied Ecology Chinese Academy of Sciences Shenyang China Graduate University Chinese Academy of Sciences Beijing China Department of forestry and Natural Resources Purdue University West Lafayette USA

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, 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 {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 {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 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 China Kunming institute of Zoology Chinese Academy of Sciences Yunnan China The Research institute of Forest Ecology Environment and Protection The Chinese Academy of Forestry Beijing 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 Key Laboratory of Silviculture and Conservation Ministry of Education Beijing Forestry University Beijing China 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 China institute of Desertification Studies Chinese Academy of Forestry Beijing 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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Principles and methods of quantitative analysis on b-axis disorder in 2.: 1 dioctahedral phyllosilicate

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chinese Science Bulletin 1997年第22期42卷 1908-1912页

作者： WANG Ling and ZHANG Zhenyu1. Changsha institute of Geotectonics, chinese {2. of sciences, Changsha 410013, china 2. institute of Geology, chinese {2. of sciences, beijing 10002., china Changsha institute of Geotectonics Chinese Academy of Sciences Changsha China institute of Geology Chinese Academy of Sciences Beijing China

IN XRD patterns of clay minerals, a phenomenon that strong peaks often have (00l) and(hkl) (k=3n) indices and show symmetric figures can be seen commonly, while a minorityof reflection peaks (hkl) (k≠3n) are comparat... 详细信息

关键词： b-axis disorder pyrophvllile 2 phyllosilicate clay minerals dioctahedral minerals orientating structure of hy-droxyls crystal structure analysis DTA-TG.

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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 {2. of Geological sciences, beijing 100081, china 2. institute of Geology, chinese {2. of Geological sciences, beijing 100037, china 3. institute of Geology and Geophysics, chinese {2. of sciences, beijing 10002., china institute of Geomechanics Chinese Academy of Geological Sciences Beijing China institute of Geology Chinese Academy of Geological Sciences Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing 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 350℃. 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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Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

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Science china(Technological sciences) 2006年第Z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG Shunzhong &WANG Hui institute of Applied Ecology, chinese {2. of sciences, Shenyang 110016, china School of forestry, Northeast forestry University, Harbin 150040, china State Key Lab of Systems Ecology, Research Center for Eco-Environmental sciences, chinese {2. of sciences, {12. 100085, china Graduate University of chinese {2. of sciences, {12. 100039, china institute of Applied Ecology Chinese Academy of Sciences Shenyang China School of forestry Northeast Forestry University Harbin China State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China Graduate University of chinese academy of {2. Beijing China

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of china (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was44.2., much lower than those for Larix forest (the RMSE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote sensing data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

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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 {2. 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 {2. 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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