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Insect Science 2011年第5期18卷 484-494页

作者： Hua-Mei Zhuang kuan-fu wang Lin Zheng Zu-Jian Wu Tadashi Miyata Gang Wu Key Laboratory of Biopesticide and Chemical Biology Ministry of Education Fujian Agriculture and Forestry University Fuzhou Fujian China Laboratory of Applied Entomology Graduate School of Bioagricultural Sciences Nagoya University Nagoya Japan

The novel full length of cytochrome P450 gene has been isolated in insecticideresistant （named CYP6CXlvl） and -susceptible （named CYP6CXlv2） Bemisia tabaci, which was identified as B biotype, in Shangjie, fujian, China （Sj）. CYP6CX1 （1 940 bp contained a 1 557 bp open reading frame） included conserved domains common to CYP6 members, such as heme-binding motif PFGEGPRFCIA, putative ＂meander＂-binding sequence ETLR and PERF in helix-K, oxygen-binding motif AGLDPV and conserved sequence PEKFNP near the carboxyl end. There were four different replacements of amino acid residues between R and S B. tabaci （Thr300 Ala, Thr354Pro, Arg486His and Ile503Thr）, among which the substitution Ile503Thr was located in the substrate recognition sites region. The mRNA transcription level of CYP6CXlvl was 2.38-fold as high as that of CYP6CXlv2. The results indicated that the CFP6CX1 from the B biotype B. tabaci in Sj was one of the CYP6 members, and enhanced CYP6CX1 expression and substitute of amino acid residues might be involved in the resistance mechanisms in field B. tabaci.

关键词： Bemisia tabaci biotype cytochrome P450s monooxygenases insecticide resistance

Modelling spatial variation in the treatment costs of nonpoint source pollution in mountainous regions of southwest China

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Journal of Mountain Science 2019年第8期16卷 1901-1912页

作者： LIU Ju fu Bin ZHANG Cheng-hu wang Yu-kuan Key Laboratory of Environment Change and Resources Use in Beibu Gulf(Ministry of Education) Key Laboratory of Earth Surface Process and Intelligent SimulationNanning Normal UniversityNanning 530001China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China

Non-point source(NPS) pollution is considered to be one of the main threats of the aquatic environment. Mountainous regions are particularly important water sources for urban areas. The various driving factors of NPS pollution such as terrain, precipitation, and vegetation type in mountainous regions show clear spatial heterogeneity. Consequently, the management systems required for NPS pollution in mountainous regions are complex. In this study, we developed a framework to estimate and map the treatment costs for NPS pollution in mountainous regions and applied this method in Baoxing County, a typical mountainous county in Sichuan Province of southwest China. The export levels of total nitrogen(TN) and total phosphorus(TP) in Baoxing County were estimated using the water purification model in InVEST(Itegrated Valuation of Ecosystem Services and Tradeoffs) tool. NPS pollutant treatment costs were calculated based on the level of pollutants exports, water yield, water quality targets, and treatment costs of NPS pollutants per unit mass. The results show that at the watershed level the amounts of TN and TP exported in Baoxing County were below threshold limits. However, at the sub-watershed level, TN and TP excesses of 291.64 and 2.96 tons per year were found, respectively, with mean TN and TP treatment costs of 6.58 US$/hm^2 and 0.35 US$/hm^2. Appraising pollution treatment cost intuitively reflects the overall expenditure in NPS pollution reduction from an economic perspective. This study provides a foundation for the implementation of Payment for Ecosystem Service(PES) and the prevention and control of NPS pollution.

关键词： Nonpoint source pollution Water treatment cost Water purification model InVEST Tool Export coefficient Spatial variation

Spatial patterns of farmland abandonment and its impact factors in the central Three Gorges Reservoir Area

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Journal of Mountain Science 2018年第3期15卷 631-644页

作者： CHEN Ying-feng wang Yu-kuan fu Bin wang Hai-wen wang Wei Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China University of Chinese Academy of Sciences Beijing 100049 China Wanzhou Station of Reservoir Eco-environment Monitoring Chongqing 404020 China Inner Mongolia Land Surveying and Planning Institute Hohhot 010010 China Survey & Planning Institute of State Forestry Administration Beijing 100714 China

The severe farmland abandonment phenomena in China have tremendously decreased the farmland usage efficiency and caused a series of profound ecological and social outcomes. The complexity of farmland abandonment necessitates a systematic research on its patterns and impact factors to underpin the dynamics of problem as well as potential solutions. This paper took Wanzhou district in the central part of Three Gorges Reservoir Area as an example to study the spatial distribution patterns of abandoned farmland at three scales, i.e., town, village, and plot, and analyzed the influence from labor transfer and farmland circulation. We conducted a survey on the distribution patterns of abandoned farmland via questionnaires at town and village scales, together with the modeling and interpretation of high-resolution aerial images taken by unmanned aerial vehicles at plot scale. Our research discloses a strong relationship between the distribution of abandoned farmland and the distance from population center at different scales. At eithertown or village scale, the abandonment proportion was recognized the highest in mid-distance areas and lowest in close-distance areas, and the per capita area of abandoned farmland increased with the distance to downtown or township. At plot scale, abandonment proportion presented exponential growth with the distance to village center, whereas the abandoned farmland was mainly distributed in the areas with distance above 500 m from the village center. Moreover, we noticed that labor transfer and farmland circulation are two important factors that influence farmland abandonment. Labor's outbound transfer distance has a positive linkage with the possibility of farmland abandonment. Finally, it is recommended that development and adoption of corresponding policies on local urbanization and farmland circulation will facilitate to alleviate farmland abandonment.

关键词： Three Gorges Reservoir Area Farmland abandonment Spatial distribution pattern Labor transfer Cultivated farmland Multi-scale Unmanned aerial vehicle

Microstructure evolution and thixoforming behavior of 7075 aluminum alloy in the semi-solid state prepared by RAP method

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International Journal of Minerals,Metallurgy and Materials 2016年第12期23卷 1404-1415页

作者： Jin-long fu Kai-kun wang Xiao-wei Li Hai-kuan Zhang School of Materials Science and Engineering University of Science and Technology Beijing Tianjin Zhonglian Precision Casting Co. Ltd.

The effects of isothermal treatments on the microstructural evolution and coarsening rate of semi-solid 7075 aluminum alloy produced via the recrystallization and partial remelting （RAP） process were investigated. Samples of 7075 aluminum alloy were subjected to cold extrusion, and semi-solid treatment was carried out for 5-30 min at temperatures ranging from 580 to 605℃. A backward-extrusion experiment was conducted to investigate liquid segregation during the thixoforming process. The results revealed that obvious grain coarsening and spheroidization occurred during prolonged isothermal treatments. In addition, higher soaking temperatures promoted the spheroidization and coarsening process because of the increased liquid fraction and the melting of second phases. Segregation of the liquid phase caused by the difference in fluidity between the liquid and the solid phases was observed in different regions of the thixoformed specimens.

关键词： aluminum alloys microstructural evolution thixoforming grain coarsening segregation

Impact of climatic factors on vegetation dynamics in the upper Yangtze River basin in China

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Journal of Mountain Science 2020年第5期17卷 1235-1250页

作者： ZHANG Yu-xin wang Yu-kuan fu Bin DIXIT Amod Mani CHAUDHARY Suresh wang Shan Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China National Society for Earthquake Technology-Nepal Kathmandu LalitpurP.0.Box 13667Nepal Chengdu Land Planning and Cadastre Center Chengdu 610074China

It is necessary to understand vegetation dynamics and their climatic controls for sustainable ecosystem *** study examines the vegetation dynamics and the effect of climate change on vegetation growth in the pristine conditions of 58 woodland National Nature Reserves(NNRs)located in the upper Yangtze River basin(UYRB)in China which are little influenced by human *** in the normalized difference vegetation index(NDVI),precipitation,and temperature in the selected NNRs were observed and analyzed for the period between 1999 and *** relationship between time-lag effect of climate and changes in the NDVI were assessed using Pearson *** results showed three major trends.1)The NDVI increased during the study period;this indicates an increase in the amount of green vegetation,especially due to the warmer climate during the growing *** NDVIs in March and September were significantly affected by the temperature of the previous *** temperatures increased significantly(P<0.05)and there was a delay between climatic factors and their effect on vegetation,which depended on the previous *** particular,the spring temperature had a delayed effect on the NDVI in summer.2)The way in which vegetation responds to climatic factors varied significantly across the *** had a greater effect on the NDVI in spring and summer and the effect was greater at higher altitudes.A similar trend was observed for precipitation,except for altitudes of 1000–2000 m.3)Temperature had a greater effect on the NDVI in spring and autumn at higher *** same trend was observed for precipitation in *** findings suggest that the vegetation found in NNRs in the upper reaches of the Yangtze River was in good condition between 1999 and 2015 and that the growth and development of vegetation in the region has not been adversely affected by climate *** demonstrates the effectiveness of nature reserves in protectin

关键词： National Nature Reserves Upper Yangtze River basin Normalized difference vegetation index Climate change Correlation analysis

Cropland physical disturbance intensity： plot-scale measurement and its application for soil erosion reduction in mountainous areas

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Journal of Mountain Science 2018年第1期15卷 198-210页

作者： LI Ming wang Yu-kuan XU Pei fu Bin TIAN Cong-shan wang Shan Institute of Mountain Hazards and Environment The Chinese Academy of Sciences Chengdu 610041 China University of Chinese Academy of Sciences Beijing 100049 China Chengdu Land Planning and Cadastre Center Chengdu 610074 China

Various kinds of human disturbances on cropland are the main reasons for soil erosion and land *** practices in mountainous areas vary greatly among cropland plots because of the heterogeneity of biophysical conditions and differences in farmers'management *** main purpose of this paper is to develop a composite index of cropland physical disturbance intensity(CLDI)to reflect the plot-scale discrepancy of potential soil erosion in mountainous *** study was based on both plot survey and household interview data,collected from six typical catchments in mountainous areas of southwestern *** kinds of physical disturbance practices and two kinds of conservation practices during one crop rotation period were synthesized to develop the CLDI *** rough set theory was referenced to avoid subjectivity during weight *** results show that conventional tillage,deep fertilization,and manual weeding are the main causes of cropland soil erosion,whereas manure application in combination with seasonal fallow reduces soil *** crop types as well as cropland location factors determine the spatial pattern of *** rotation modes with major crops of tobacco and maize resulted in a maximal CLDI,and cropland plots with a distance radius of 150 meters away from households received the most intensive physical *** results are critical to help better protect rural environments in mountainous *** on the results,methods to reduce cropland soil erosion are suggested.

关键词： Cropland disturbance intensity Soil erosion Farming practices Farmers' behavior Rough set theory Index development

Agricultural opportunity costs assessment based on planting suitability:a case study in a mountain county in southwest China

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Journal of Mountain Science 2017年第12期14卷 2568-2580页

作者： liu ju fu bin wang yu-kuan lu ya-feng xu pei institute of mountain hazards and environment chinese academy of sciencesChengdu 610041China key laboratory of environment change and resources use in beibu gulf(guangxi teachers education university) ministry of educationNanning 530001China wanzhou key regional ecology and environment monitoring station Chongqing 404020China

Payment for ecosystem services(PES) has become an increasingly popular means of ecosystem conservation. Opportunity cost is an important factor to increase the investment efficiency of PES ***, the distribution of opportunity cost is usually unclear in mountainous regions due to the obvious environment changes. In this study, we developed a framework to assess the distribution of agricultural opportunity costs in mountainous regions and applied this method to Baoxing County, a typical mountainous county in Sichuan Province of southwest China. Planting suitability of 17 crops was assessed based on agricultural statistics and natural conditions data within a GIS *** opportunity cost was quantified with a weighted summation of farmers' willingness to cultivate and each crop's opportunity cost. Finally,specific agricultural opportunity cost was obtained according to the spatial areas of the protection programs and land use status. The results showed that agricultural opportunity costs of PES in Baoxing County were estimated to be more than $30 million,with a mean of 400.85 $/ha. Agricultural opportunity costs in mountainous regions displayed some obvious spatial variation and areas with lower agricultural opportunity costs could be selected as priority areas for PES. Our findings revealed that the planting suitability evaluation can make agricultural opportunity costs mapping more reasonable. It will be helpful for the PES programs implementation in mountainous regions.

关键词： Opportunity cost Planting suitability Willingness to accept Ecosystem service Spatial variation Baoxing County

Study on rain-runoff process in the peripheral mountainous area of the Sichuan Basin

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Chinese Journal Of Geochemistry 2008年第2期27卷 183-188页

作者： fu Bin wang Yu-kuan REN Yi LIU Cheng XU Pei Key Laboratory of Mountain Surface Process and Hazards Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Studies on rain-runoff process in the peripheral mountainous area of the Sichuan Basin, which is regarded as a key ecological shelter, will contribute to flood control and environmental protection for the Upper Yang-tze River Basin. In two typical catchments-the fujiang River Catchment and the Wujiang River Catchment, rainfall simulations have been conducted to study the rain-runoff processes of yellow soil and limestone soil in three types of land use-forestland, farmland and grassland. Results showed that (1) within the same rainfall process, overland flow occurs first on farmland, then on grassland, and finally on forestland; (2) soil surface coverage has a great impact on the occurrence and amount of overland flow. The runoff amount can increase 2-4 times after the coverage is removed;(3) the infiltration before the occurrence of overland flow will decrease because of higher gravel contents of soil, but it takes no effect on infiltration once overland flow becomes stable; (4) the runoff coefficient of the limestone soil forestland is greater than that of the yellow soil forest land, but less than that of the farmland; (5) three empirical infiltration models, including Horton' model, Kostiakov' model, and modified Kostiakov' model, were compared by using the observed results under rainfall simulation. The results showed that the Kostiakov' model performed better than both the Horton' model and modified Kostiakov model. According to the results of this research, the Kostiakov's model can be used to simulate rainfall infiltration when water erosion is modeled in the peripheral mountainous area of the Sichuan Basin.

关键词：山地四川盆地降雨量河流

Coupling dehydrogenation of isobutane in the presence of carbon dioxide over chromium oxide supported on active carbon

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Chinese Chemical Letters 2008年第9期19卷 1059-1062页

作者： Jian Fei Ding Zhang Feng Qin Xue kuan Li Guo fu wang Jian Guo wang State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences P.O. Box 165 Taiyuan 030001 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

The dehydrogenation of isobutane （IB） to produce isobutene coupled with reverse water gas shift in the presence of carbon dioxide was investigated over the catalyst Cr2O3 supported on active carbon （Cr2O3/AC）. The results illustrated that isobutane conversion and isobutene yield can be enhanced through the reaction coupling in the presence of carbon dioxide. Moreover, carbon dioxide can partially eliminate carbonaceous deposition on the catalyst and keep the active phase （Cr2O3）, which are then helpful to alleviate the catalyst deactivation.

关键词： Dehydrogenation Isobutane Carbon dioxide Isobutene Reaction coupling Cr2O3/AC

Synthesis and Crystal Structure of Cu(II) Complex with 2,9-Bis(n-2',5'-diazaheptanyl)-1,10-phenanthroline

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Chinese Journal of Structural Chemistry 2004年第7期23卷 778-782页

作者： LIFeng-Hua LIUTian-fu LINHua-kuan ZHUShou-Rong wangZhong-Ming DepartmentofChemistry NankaiUniversityTianjin300071China

The Cu(II) complex with the ligand 2,9-bis(n-2?5?diazaheptanyl)-1,10-phenan- throline (L) has been synthesized and characterized by single-crystal X-ray diffraction. It crys- tallizes in the monoclinic system, space group P21/n with a = 12.549(4), b = 13.544(4), c = 16.767(5) ? = 107.179(5), C22H32Cl2N6CuO8, Mr = 642.98, V = 2722.5(13) 3, Z = 4, Dc = 1.569 g/cm3, ?= 1.056 mm-1, F(000) =1332, the final R = 0.0733 and wR = 0.1581. The X-ray analysis revealed that the Cu(II) ion is coordinated by six nitrogen atoms of the ligand, in which two nitrogen from phenanthroline and another two from the imine groups near phenanthroline are in the equatorial plane while the two from imine groups at the end of both arms in the axial positions. The coordination geometry can be described as a compressed octahedron.

关键词： phenanthroline Cu(II) complex crystal structure compressed octahedron