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Physical mechanisms of plant roots affecting weathering and leaching of loess soil

Science china Earth sciences 2006年第9期49卷 1002-1008页

作者： LI Yong1,2. ZHANG Qingwen1,2. WAN Guojiang3, HUANG Ronggui3, PIAO Hechun3, BAI Lingyu2.& LI Lu2.1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, institute of Soil and Water Conservation, Chinese academy of {2., Yangling 712.00, china 2. institute of Agro-environment and Sustainable Development, Chinese academy of agricultural {2., beijing 100081, china 3. institute of Geochemistry, Chinese academy of {2., Guiyang 550002. china 1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling 712100 China 2. institute of Agro-environment and Sustainable Development Chinese Academy of Agricultural Sciences Beijing 100081 China 3. institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

plant roots have potential impacts on soil mineral weathering and *** objective is to understand the physical mechanisms of plant roots affecting weathering andleaching of loess soil. Root densities were measured through the method of a large-size dug profile,and transport fluxes of soil elements were determined using an undisturbed monolith soilinfiltration device on the hilly and gully regions of the Chinese Loess Plateau. The results showthat the improvement effects of soil {2. by plant roots are mainly controlled by the densityand weight of the fibrous roots with the diameters less than 1 mm. plant roots have the strongereffects on soil physical properties than chemical properties. The principal components analysis(PCA) indicates that soil physical properties by plant roots account for 56.7% of variations in soil{2. whereas soil chemical properties and pH contribute about 2..2. of the soil *** roles of plant roots in controlling soil weathering and leaching increased in the followingorder: infiltration enhancement > increase of bio-active substance > stabilization of soilstructure. The effects of plant roots on soil mineral weathering and leaching can be quantifiedusing the multiple regression models with the high prediction accuracies developed in this study.

关键词： plant roots, soil weathering and leaching rates, soil environment field, principal components analysis (PCA), Chinese Loess Plateau.

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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, Chinese {2. of sciences, beijing 100101, china institute of forestry Science, Chinese {2. of forestry Science, beijing 100091, china Research Center for Eco-{12. sciences, Chinese {2. 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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Potential land for plantation of Jatropha curcas as feedstocks for biodiesel in china

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Science china Earth sciences 2010年第1期53卷 120-127页

作者： WU WeiGuang 1,2.3,HUANG JiKun 1,3 & DENG XiangZheng 1,3 1 institute of Geographic sciences and Natural Resources Research,Chinese {2. of sciences,beijing 100101,china 2.Department of Economics and Management,Zhejiang forestry University,Linan 311300,china 3 Center for Chinese agricultural Policy,Chinese {2. of sciences,beijing 100101,china 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China2. Department of Economics and Management Zhejiang Forestry University Linan 311300 China3. Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China

As a renewable energy,biofuel has attracted great attention in china and the rest of *** with the national food security,china recently has shifted its biofuel development priority from grain-based to non-grain-based biofuels,including forest-based biodiesel,since *** curcas is one of major biodiesel ***,there is rising debate on availability of land for expanding Jatropha curcas *** overall goal of this paper is to evaluate potential land for Jatropha curcas used as feedstock for biodiesel in *** on remote sensing data on land use,data on meteorological,soil and land slope,and suitable {2. for Jatropha curcas plantation,this study uses Agro Ecological Zone method and considers social-economic constraints to evaluate potential suitable land for Jatropha curcas plantation in china's major Jatropha curcas production region,Southwest *** results show that while there are some potential lands to expand Jatropha curcas areas,amount of these lands will hardly meet the government's target for Jatropha curcas-based biodiesels development in the *** may need to reconsider its long-term targets on the development of Jatropha curcas-based biodiesels.

关键词： biodiesel Jatropha curcas potential land suitability evaluation Southwest china

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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 {2. 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 {2. 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 -10.5per 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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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, china 2.Kunming institute of Zoology, Chinese academy of {2., Yunnan, 6502.3, china 3 The Research institute of Forest Ecology, environment and Protection, The Chinese academy 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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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 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 {2.ing) 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, {2. 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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Invasive mechanism and management strategy of Bemisia tabaci(Gennadius) biotype B:Progress report of 973 Program on invasive alien species in china

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Science china(Life sciences) 2009年第1期52卷 88-95页

作者： WAN FangHao1,ZHANG GuiFen1,LIU ShuSheng2.LUO Chen3,CHU Dong4,ZHANG YouJun4,ZANG LianSheng2.JIU Min2.Lü ZhiChuang1,CUI XuHong1,ZHANG LiPing4,ZHANG Fan3,ZHANG QingWen5,LIU WanXue1,LIANG Pei5,LEI ZhongRen1 & ZHANG YongJun1 1 State Key Laboratory for Biology of plant Diseases and Insect Pests,institute of plant Protection,Chinese Acadeny of Agriculture sciences,beijing 100094,china 2.institute of Applied Entomology,Zhejiang University,Hangzhou 31002.,china 3 institute of plant and environment Protection,beijing academy of agricultural and forestry sciences,{12.,china 4 institute of Vegetables and Flowers,Chinese Acadeny of Agricullare sciences,beijing 100081,china 5 Department of Entomology,china Agriculture University,beijing 100094,china 1. State Key Laboratory for Biology of plant Diseases and Insect Pests Institute of Plant Protection Chinese Acadeny of Agriculture Sciences Beijing 100094 China 2. institute of Applied Entomology Zhejiang University Hangzhou 310029 China 3. institute of plant and {2. Protection Beijing Academy of Agricultural and Forestry Sciences Beijing 100089 China 4. institute of Vegetables and Flowers Chinese Acadeny of Agricullare Sciences Beijing 100081 China 5. Department of Entomology China Agriculture University Beijing 100094 China

Bemisia tabaci(Gennadius) biotype B,called a "superbug",is one of the most harmful biotypes of this species complex *** this report,the invasive mechanism and management of *** biotype B,based on our 5-year studies,are *** *** biotypes,B,Q,ZHJ1,ZHJ2.ZHJ3 and FJ1,have been identified in *** B dominates the other biotypes in many regions of the *** diversity in biotype B might be induced by host plant,geographical conditions,and/or insecticidal *** activities of CarE(carboxylesterase) and GSTs(glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants,which might have increased its resistance to *** higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host *** adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein *** indigenous *** biotypes were displaced by the biotype B within 2.5 *** asymmetric mating interactions and mutualism between biotype B and begomoviruses via its host plants speed up widespread invasion and displacement of other *** biotype B displaced Trialeurodes vaporariorum(Westwood) after 4-7 generations under glasshouse *** adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its successful displacement of *** ability of the biotype B to switch to different host plants may enrich its host plants,which might enable it to better compete with *** predatory natural enemies possess greater ability to suppress *** under field *** kairomones in the 3rd and 4th instars of biotype B may provide an important stimulus in host searching and location by its *** present results provide useful information in explaining the mechanisms of genetic diversity,e

关键词： National Basic Research and Development Program of china(973 Program) invasive alien species Bemisia tabaci biotype B ecological mechanisms genetic diversity sustainable management

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Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science china Earth sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2.3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5, LIU Linshan1, 2.& ZHENG Du1 1. institute of Geographic sciences and Natural Resources Research, Chinese {2. of sciences, beijing 100101, china 2. Graduate School of the Chinese {2. of sciences, beijing 100039, china 3. College of Resources and environment, Southwest agricultural University, Chongqing 400716, china 4. The Ministry of Science and Technology, P. C. china, beijing 100862. china 5. Chengdu institute of Biology, Chinese {2. of sciences, Chengdu 610041, china 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the Chinese academy of sciences 100039 Beijing China 3. College of Resources and environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of Science and Technology P. C. China 100862 Beijing China 5. Chengdu institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2.00 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2.00, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2.00, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

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Geographical Agglomeration of Chinese Manufacturing Industries

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中国人口·资源与环境：英文版 2007年第2期5卷 3-11页

作者： Zhang Hua 1, 2. Zheng Wei3 1. institute of Geographical sciences and Natural Resources Research, Chinese {2. of sciences, beijing 100101, china 2. Graduate School of the Chinese {2. of sciences, beijing 100039, china 3. School of Geography, beijing Normal University, beijing 100875, china institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School of the Chinese academy of sciences Beijing 100039 China School of Geography Beijing Normal University Beijing 100875 China

Based on the plant level data from the First National Census of Basic Units, the Second National Census of Basic Units, and the First National Economic Census of china, this paper ex- amines the geographical agglomeration of Chinese manufacturing industries at a more disaggregated level both by industrial classi-fication and spatial unit analysis. Applying the agglomeration index proposed by Maurel and Sedillot, studies show that the most agglomerated industries are resource-intensive, and capital and technology intensive while industries demanding localized inputs or serving localized markets or favored by local governments are fairly dispersed. The more disaggregated industries are more spa- tially agglomerated. At the finer spatial scale, industries are more dispersed. Results indicate that within-county spillovers are stronger than nearby-county spillovers, and within-prefecture spillovers are stronger than nearby prefecture spillovers. Local- ized spillovers are still quite substantial at a range beyond that of counties. Comparing the agglomeration index of Chinese manu- facturing industries in 1996, 2.01 and 2.04, agglomeration seems to be a general tendency. Results also indicate that some industries have experienced remarkable changes in their levels of agglom- eration in the period 1996–2.04.

关键词： industrial agglomeration manufacturing industries the MS index

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Present status and development on biological nitrogen fixation research in china

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Chinese Science Bulletin 2003年第10期48卷 954-960页

作者： SHEN Shihua & JING Yuxiang Key Laboratory of Photosynthesis and plant-environment MolecularPhysiology, {2. of Botany, Chinese academy of sciences, beijing 100093, china Key Laboratory of Photosynthesis and plant-environment Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

This presentation introduces the advances inbiological nitrogen fixation research abroad, in particular,describes the great progress and achievements on itsresearch in china as follows: collection of rhizobial resources and establishment of the largest database of Rhizobium inchina, correction and development of Rhizobium taxonomy in international; discovery of a couple of nif genes,identification and unification of linkage among the nif gene operons of Klebsiella pneumoniae, finding of regulative mechanism of positive regulation nif gene and its sensitivity to oxygen, temperature; finding of the activity of nodulation gene nodD3 product in Sinorhizobium meliloti which is notcontrolled by flavonoid produced from its host alfalfa;finding of the association between expression of genes coding the products for carbon utilization and nitrogen metabolism and their regulations; chemical synthesis of nodulationfactor of Sinorhizobium meliloti; constructions of engineered nitrogen fixers and utilization in practice based on theresearch of gene expression and regulation; chemicalsimulation of the structure and function of nitrogenase and bringing forward the model of nitrogenase active center for the first time in international and synthesis of modelcompounds which were paid attention by colleagues abroad. Finally, the development of nitrogen fixation research inchina in future has been put forward, suggesting that the nifgene regulation and its role in providing crops with nitrogen element, signal transduction and molecular interactions between Rhizobium and legume, coupling between carbonand nitrogen metabolisms, nitrogen fixation andphotosynthesis, and functional genomics of nitrogen-fixing nodule symbiosis, etc., would be actively worked on.

关键词：现状发展生物固氮技术中国固氮酶基因表达微生物植物相互作用化学模型

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