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Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, china

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Science china.Earth sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1, LIANG Tao1 & TAO Shu2 1. institute of Geographical sciences and Natural Resources research, chinese academy of sciences, beijing 100101, china.2. Laboratory for Earth Surface Processes, Peking University, beijing 100871, china 1. institute of Geographical sciences and Natural Resources research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for Earth Surface Processes Peking University 100871 Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1952―2003 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952―1983, the average input and output amount of HCHs through agricultural application and degradation are 130 t and 150 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92% of total transfer fluxes of HCHs isomers. There were approximately 253t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1983, and this percentage may descend to 0.5% after 20 years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

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 310029,china.3 institute of Plant and Environment 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 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 Environment 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 225 *** 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

OREINTATION AND PRIORITY AREAS OF DRY LAND AGRO-TECHNOLOGY DEVELOPMENT IN china

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Natural Disaster Reduction in china 2003年第1期 25-28页

作者： Zhang Yanqing (research Management Department, chinese academy of agricultural sciences, beijing 100081, china. ZhaoYunfeng

Addressing major problems faced by dry land agro technology development and based on a summarization of existing domestic dry land agro tech and overseas dry land agro tech development trend, this paper proposes a direction and technological option for china.s dry land agro tech development and also puts forward research priorities in the future.

关键词： dry land agriculture technological direction priority areas

A human－ecology approach to environmental design──An integrative human－ecology design derived from chinese agricultural cultur eexperiences

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Journal of Environmental sciences 1994年第4期6卷 478-485,485页

作者： Hu Dan (research Center for Eco-Environmental sciences , chinese academy of sciences , beijing 100085, china.

Based on fundamental principles of ecology ,the ecological philosophy connotation of Feng-Shui(Wind and Water) concept from experiences of chinese agricultural culture was first discussed , and then hu-man-ecological implications of Feng-Shui environment architecture is analyzed. As a theoretical integrationbetween human ecology and Feng-Shui theory ,“environment” and “environmental design” concepts were re-examined and given new definitions. With holistic principles of human ecological design in the context ofFeng-Shui , essential technical ways of integrative human ecological design were explored in the presentationof a case study of an urban environmental design in east china.

关键词： integrative environmental design human ecology Feng-Shui environment architecture.

Cloning and sequence analysis of a gene encoding polygalacturonase-inhibiting protein from cotton

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Progress in Natural Science:Materials International 2003年第2期 41-46页

作者： DOU Daolong, WANG Bingshan, TANG Yixiong, WANG Zhixing and SUN Jingsan ( institute of Botany, chinese academy of sciences, beijing 100093, china.Biotechnology research institute, chinese academy of agricultural sciences, beijing 100081, china. institute of Botany，chinese academy of sciences，beijing 100093 china.Biotechnology research institute，chinese academy of agricultural sciences，beijing 100081，china Biotechnology research institute，chinese academy of agricultural sciences，beijing 100081，china institute of Botany，chinese academy of sciences，beijing 100093，china

Abstract Polygalacturonase- inhibiting proteins (PGIP) play important roles in plant defense of pathogen, especially fungi. A pairof degenerated primers is designed based on the conserved sequence of 20 other known pgip genes and used to amplify Gossypium barbadense cultivation 7124 cDNA library by touch-down PCR. A 561 bp internal fragment of the pgip gene is obtained and used to designthe primers for rapid amplification of cDNA ends. A composite pgip gene sequence is constructed from the products of 5' and 3' RACE,which are 666 bp and 906 bp respectively. Analysis of nucleic acid sequence shows 69.2% and 68. 7% similarity to Citrus and Ponciruspgip genes, respectively. Its open reading frame of the gene encodes a polypeptide of 330 amino acids, in which 10 leucine-rich repeats ar-range tandemly. A new set of primers is designed to the 5' and 3' ends of the gene, which allows amplification of the full-length gene fromthe cotton cDNA library. Genomic DNA analysis reveals that this gene has no intron.

关键词： Gossypium barbadense polygalacturonase-inhibiting protein ( pgip ) gene rapid amplification of cDNA ends (RACE) sequence analysis leucine-rich repeats (LRRs) .

The new interpretation of support vector machines on statistical learning theory

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Science china.Mathematics 2010年第1期53卷 151-164页

作者： ZHANG ChunHua 1 , TIAN YingJie 2 & DENG NaiYang 3,1 School of Information, Renmin University of china. beijing 100872, china.2 research Center on Fictitious Economy and Data Science, chinese academy of sciences, beijing 100080, china.3 College of Science, china.agricultural University, beijing 100083, china 1. School of Information Renmin University of China Beijing 100872 China2. Research Center on Fictitious Economy and Data Science Chinese Academy of Sciences Beijing 100080 China3. College of Science China Agricultural University Beijing 100083 China

This paper is concerned with the theoretical foundation of support vector machines (SVMs). The purpose is to develop further an exact relationship between SVMs and the statistical learning theory (SLT). As a representative, the standard C-support vector classification (C-SVC) is considered here. More precisely, we show that the decision function obtained by C-SVC is just one of the decision functions obtained by solving the optimization problem derived directly from the structural risk minimization principle. In addition, an interesting meaning of the parameter C in C-SVC is given by showing that C corresponds to the size of the decision function candidate set in the structural risk minimization principle.

关键词： C-support vector classification the minimization principle of the structural risk KKT conditions

research on the method for retrieving soil moisture using thermal inertia model

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Science china.Earth sciences 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2 1. Information College, South china.agricultural University, Guangzhou 510642, china.2. Graduate University of chinese academy of sciences, beijing 100049, china 1. Information College South China Agricultural University Guangzhou 510642 China 2. Graduate University of chinese academy of sciences Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

Monitoring of rice crop using ENVISAT ASAR data

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Science china.Earth sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2, SUN Guoqing1,3 & PANG Yong4 1. State Key Laboratory of Remote Sensing Science, institute of Remote Sensing Applications, chinese academy of sciences, beijing 100101, china.2. Graduate University of chinese academy of sciences, beijing 100039, china.3. Department of Geography, University of Maryland, College Park, MD 20742, USA 4. Forest Remote Sensing Lab, research institute of Forest Resource and Information Technology, chinese academy of For-estry, beijing 100091, china 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China 2. Graduate University of chinese academy of sciences Beijing 100039 China 3. Department of Geography University of Maryland College Park MD 20742 USA 4. Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing 100091 China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

A Transient Expression System for the Functional Assessment of Early Response Genes on the Powdery Mildew Infected Barley or Wheat Leaves

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agricultural sciences in china 2003年第10期2卷 1061-1068页

作者： LI Ai-li (Key Laboratory of Crop Germplasm and Biotechnology, Ministry of Agriculture/institute of Crop Germplasm Resources, chinese academy of agricultural sciences, beijing 100081,P.R.china. Key Laboratory of Crop Germplasm and Biotechnology Ministry of Agriculture/Institute of Crop Germplasm Resources Chinese Academy of Agricultural Sciences Beijing 100081 P. R. China

The principle and the basic steps of the transient assay system for the functional assessment of early response genes on the powdery mildew infected barley or wheat leaves were summarized in brief. The development of this technology and its extensive application were reviewed. Future studies on this approach were recommended in this paper.

关键词： Transient expression system Powdery mildew Barley Wheat