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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,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 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

Wettability of Poplar Wood Impregnated by Phenol-formaldehyde Resin

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chinese forestry Science and Technology 2009年第2期8卷 19-23页

作者： CHAI Yubo LIU Junliang WANG Ming Research institute of Wood Industry,chinese academy of forestry,Beijing {2.,P.R.China

In this study,plantation poplar wood was first impregnated by low molecular weight phenol-formaldehyde(PF) resin solution by vacuum-pressure *** then the wettability of sanded and non-sanded radial and tangential sections from un-impregnated and impregnated poplar wood was tested respectively by the measurement of contact angles using different ***,the surface free energy of different samples was estimated by the plot extrapolation *** results showed that the wettability of woo...

关键词： impregnation wettability contact angle surface free energy

Characterization of MASDs of surface soils in north China and its influence on estimating dust emission

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chinese Science Bulletin 2004年第20期49卷 2169-2176页

作者： MEI Fanmin1,2. ZHANG Xiaoye1, LU Huayu1, SHEN Zhenxing1 & WANG Yaqiang1 1. State Key Laboratory of Loess and Quaternary Geology, institute of Earth Environment, chinese {2. of Sciences, Xian 710075, China 2. Xian University of Engineering Science and Technology, Xian 710048, China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi''an 710075 China Xi''an University of Engineering Science and Technology Xi''an 710048 China

The micro-aggregated size distribution (MASD) of surface soil is an important parameter for modelling dust emission. However, there is no dataset of MASDs of all sur-face soil types in north China. The MASDs are here pre-sented, measured by dry sieving, for typical surface soil sam-ples, including sandy soil, gravelly sand soil, gravelly loam soil, loam soil and silt loam soil, collected from sandy deserts, Gobi deserts, oases, farmlands in steppe regions and steppe areas in north China. The MASDs of various surface soil types exhibit a combination of several log-normal distribu-tions of five separated sizes with mean mass median diame-ters (MMDs) of 90, 2.0, 390, 600 and 980 mm, respectively, and mean standard deviations (SDs) of 1.2., 1.40, 1.2., 1.35 and 1.2. respectively. The log-normal distributions corre-spond to very fine sand, fine sand, medium sand, coarse sand and very coarse sand population. On the basis of characteri-zation of the retrieved MASDs of various surface soil types in north China, dust emission fluxes are modelled by a dust production model (DPM model). It is shown that dust emis-sion has been significantly influenced by MASDs. Fine sand and very fine sand are always associated with the highest dust emission fluxes. Emission fluxes of the medium sand, gravelly sand soil, gravelly loam soil and loam soil are lower than those of very fine sand and fine sand, but larger than those of the coarse sand. The differences in dust emission fluxes vary among the different soil types from 101 to 103 mg·m-2.s-1. Dust emission fluxes from sandy deserts and farmlands covered with sand sheets in north China rang from 101 to 104 mg·m-2.s-1 while those from Gobi deserts, farmlands and steppes with gravelly desertification range from 101 to 102.mg·m-2. s-1. The modelled results indicate that deserts and farmlands with sand are the major dust sources in north China.

关键词：华北地区 MASDs 微块状粒度分布地面土壤粉尘排放壤土大气污染气溶胶

Analysis on Impact Factors for Forest Management Income of Forest Farmers in China

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chinese forestry Science and Technology 2008年第4期7卷 61-67页

作者： ZHANG Decheng1 LI Zhiyong1 YANG Hongguo1 BAI Dongyan2.1. institute of forestry Policy and Information, {2., Beijing 100091, P. R. China 2. Business Department, Nanyang Technology institute, Nanyang 473004, P. R. China

Based on the investigation in Anji County of Zhejiang Province and Ba'nan District of Chongqing, this paper analyzed the characteristics of forest management behaviors of forest farmers in China and the impact factors for forest management income, and then came up with some policy recommendations to increase the forest management income of forest farmers. It argued that the factors to impact on forest management income of forest farmers in China include the choice of forest products type, the elements in forest production and management, the development of forest products processing sector at regional level, and the government's forest management system. It is suggested that government promote the production of non-wood forest products, guide the forestry sector restructuring, reform the logging management system and forestry public finance and taxation system, regulate forest land transfer and foster forest products processing enterprises to increase the farmers' income forest management.

关键词： forest management forest farmer income impact factor

State and Potential of Forest Carbon Market in China

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chinese forestry Science and Technology 2010年第1期9卷 14-18页

作者： TAN Xiufeng1 ZHOU Fengzhi2.1. Research institute of forestry Policy and Information, {2., Beijing100091, P. R. China 2. Huyuan Forest Farm, Daxing’anling, Huyuan 165033, P. R. China

China has been making efforts to improve climate changes which have drawn international attentions since China formally signed UN Climate Change Framework in 1992.and ratified Kyoto Protocol in August 2.02. The area of China’s forest plantation ranks the first at present so global close attention is paid to forest carbon market in China. This article introduces that 5 110 million t of carbon dioxide equivalent have been sequestrated by China’s forest during 1980 to 2.05, China will have 4.2.billion t of carbon dioxide emission reduction market potential and contribute more forest carbon credits to the international community.

关键词： forest carbon market state potential China

Estimating Strength of Finger-jointed Dimension Lumber by Nondestructive Methods

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chinese forestry Science and Technology 2010年第2期9卷 62-67页

作者： ZHOU Haibin REN Haiqing LUO Xiuqin JIANG Jinghui Reseach institute of Wood Industry, chinese academy of forestry, Beijing {2., P.R.China

Structural finger-jointed (FJ) lumber was used mainly in structural applications including glue-laminated beams and wooden I-joists and more recently in parallel chord wood trusses. The paper evaluated strength properties of structural FJ lumber by three nondestructive methods (edge-wise bending, longitudinal and transversal vibration) in order to find an alternative to traditional evaluation methods. Lumber was sawn from the logs following a pattern typically used in China to maximize the volume of recovered sawn timbers. After kiln-dried, these rough-sawed lumbers were planned to 4.5 cm thick, 9.0 cm wide and 100cm long. The lumber pieces were assigned to two groups (low-grade and high- grade groups) according to their dynamical modulus of elasticity. FJ lumber was produced by cutting a series of sloping fingers (finger length 2., 2. and 35 mm) on the end of the wood pieces to be joined and interlocking the two pieces. Each finger-jointed lumber with one same finger length had three types: L-L, L-H and H-H. The FJ lumber was nondestructively tested using edge-wise bending, longitudinal and transversal vibration methods. After three methods, tensile and bending strengths of FJ lumber were tested to build dynamical relationships between MOE and strengths. The results showed that dynamic MOEs were good indicators of the static MOE, but both dynamic MOE and static MOE had a bad correlation with tensile strength of finger jointed lumber.

关键词： finger-jointed lumber timber construction tensile strength bending strength nondestructive method

El Nino And Forest Fire In Yunnan Province, Southwest China -New Way to Study Three Essential Factors of Forest Fire

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chinese forestry Science and Technology 2003年第1期2卷 16-23页

作者： ZHAOXianwen SI LinResearch institute of Resource Information Techniques. chinese academy of forestry.Wan Shou Shan. Beijing {2.. Chinazhaoxw @ info.forestry. ac. en

Three essential factors of forest fire (fire source, environment, and litter) were taken as the point of view, and has approached the forecast method of forest fire in tropical area of southwest China in a macroscopic scale. This study supported by mathematical method was from a new angle. For example, in the aspect of forest fire forecast, it has been thought over that most forest fire is artificial fire, which has lots of randomness. So it could be studied in a kind of Markov random processes. In the ...

关键词： EL Nino forest fire remote sensing Markov litter

Effect of Metal Oxide on Electrical Resistivity of Conductive Wood Charcoal

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chinese forestry Science and Technology 2011年第Z1期10卷 7-11页

作者： HU Nana LIN Lanying FU Feng Research institute of Wood Industry, chinese academy of forestry, Beijing {2., P. R.. China

To analyze the effect of metal oxide on electrical resistivity of conductive wood charcoal,wood powder of Masson pine was mixed with ferric oxide (Fe_2._3) and nickel oxide (NiO), respectively,and then the mixed powders were carbonized at high temperature in a laboratory-scale tube furnace in a nitrogen atmosphere. DCY-3 resistivity tester was used to measure electrical resistivity of conductive wood charcoal. When carbonization temperature was 12.0 ℃, the electrical resistivity of controlsamples, Fe_2._3 (4%) added samples, and NiO (4%) added samples was 0.104 Ω·lcm, 0.071 Ω·lcm, and 0.066 Ω·lcm, respectively. When carbonization temperature was 1 500 ℃, the electrical resistivity of control samples, Fe_2._3 (4%) added samples, and NiO(4%) added samples was 0.091 Ω·lcm,0.052.Ω·lcm, and 0.052.·lcm, respectively. And electrical resistivity of conductive wood charcoaldecreased from 0.060Ω·lcm to 0.041Ω·lcm when the ferric oxide addition increased from 2. to 10%.The results showed that the electrical resistivity of conductive wood charcoal decreased with the increase of carbonization temperature. Ferric oxide and nickel oxide could be used as catalysts todecrease electrical resistivity of conductive wood charcoal. And electrical resistivity of conductivewood charcoal reduced with increasing the ferric oxide addition.

关键词： conductive wood charcoal ferric oxide nickel oxide carbonization temperature electrical resistivity

Current Situation and Challenges of Plantation Development in China

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chinese forestry Science and Technology 2009年第4期8卷 48-52页

作者： TAN Xiufeng1 ZHOU Fengzhi2.1. Research institute of forestry Policy and Information, {2., Beijing 100091, P. R. China 2. Huyuan Forest Farm, Daxing’anling, Heilongjiang, Huzhong 165033, P. R. China

The area of plantation in China ranks the first in the world. But, many challenges are still faced in the development of China’s plantation. A review of plantation in China was presented and the challenges were analyzed. The plantation features juvenile and middle age class with low diameter at breast height. There are the risks of pests and diseases in plantation, the potential decline in land fertility and bio-diversity, all of which are unfavorable to a healthy development of plantations.

关键词： plantation situation challenge China