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chinese Science Bulletin 1999年第S2期44卷 125-126页

作者： BAI Zhanguo~(1,2. and WAN Guojiang~1 1. state key {2. of Environmental Geochemistry, institute of Geochemistry, chinese academy of sciences, Guiyang 550002. china 2. state key laboratory of plant nutrition research of chinese ministry of agriculture institute of soil and fertilizer, chinese academy of agricultural sciences, beijing 100081, china

WEST Yunnan and central Guizhou with variable altitudes and similar latitudes, located in the Yunnan-Guizhou Plateau of the eastern slope uplifting Himalayas, were selected as study areas in this note. Thetwo areas consist mainly of carbonate rocks discontinuously covered by similar soil types with severe soiland water loss except Lugu Lake catchment. Climate of the study areas is subtropical monsoon, apparently influenced by mingled southeastern monsoon and southwestern monsoon with abundant *** study is to comparatively describe distribution and inventory of 7Be and 137Cs in the sediments of Erhai Lake, Lugu Lake and Hongfeng Lake as well as in 2. surface soil profiles of their *** results have shown that: （i） In all the soil profiles, 7Be activities decrease exponentially with soil depth. 7Be apparent ac-

关键词： radionuclides soils sediments china.

Geochemical records of carbon in recent sediments of Erhai Lake, china: Implication of effects of the Himalayas uplift on global environmental changes

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chinese Science Bulletin 1999年第S2期44卷 123-124页

作者： WAN Guojiang~1, BAI Zhanguo~(1,2., WANG Haoran~1 and HUANG Ronggui~1 1. state key {2. of Environmental Geochemistry, institute of Geochemistry, chinese academy of sciences, Guiyang 550002. china 2. state key laboratory of plant nutrition research of chinese ministry of agriculture, institute of soil and fertilizer, chinese academy of agricultural sciences, beijing 100081, china

THE formation and uplift of the Himalayas and the Tibetan Plateau may have been responsible for the past150 Ma global environmental changes, resulting in the development of a three-tiered landform in southernchina. The Yunnan-Guizhou Plateau, as the middle tier in eastern slope of the Himalayas, has beencomplex environmental unit with great altitude gradients and plateau landform characters. Both monsoonsfrom the Pacific and the Indian resulting in apparent environmental changes on variable time scales influence it. Environmental geochemical effect of low latitude-high altitude could be yielded, and well recorded in the geological bodies in this region. To build and verify a quantitative model of environmental evolution it is necessary to obtain high-resolution data of elemental cycles and mass equilibrium.

关键词： records sediments Erhai Lake Himalayas uplift global environmental changes.

Denitrification Losses and N_2. Emissions from Nitrogen fertilizer Applied to a Vegetable Field

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Pedosphere 2006年第3期16卷 390-397页

作者： CAO Bing He Fa-Yun Xu Qiu-Ming Yin Bin CAI Gui-Xin state key {2. of soil and Sustainable agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate School of the chinese academy of {2. Beijing 100039 （China） institute of plant {2. and Resources Beijing Academy of Agricultural and Forestry Sciences Beijing 100089 （China）

A field experiment was conducted on chinese cabbage （Brassica campestris L. ssp. pekinensis （Lour.） Olsson） in a Nanjing suburb in 2.03. The experiment included 4 treatments in a randomized complete block design with 3 replicates： zero chemical fertilizer N （CK）; urea at rates of 300 kg N ha^-1 （U300） and 600 kg N ha^-1 （U600）, both as basal and two topdressings; and polymer-coated urea at a rate of 180 kg N ha^-1 （PCU180） as a basal application. The acetylene inhibition technique was used to measure denitrification （N2.＋ N2.） from intact {2. cores and N2. emissions in the absence of acetylene. Results showed that compared to （3K total denitrification losses were significantly greater （P ≤ 0.05） in the PCU180, U300, and U600 treatments,while N2. emissions in the U300 and U600 treatments were significantly higher （P ≤ 0.05） than （3K. In the U300 and U600 treatments peaks of denitrification and N2. emission were usually observed after N application. In the polymer-coated urea treatment （PCU180） during the period 2. to 40 days after transplanting, higher denitrification rates and N2. fluxes occurred. Compared with urea, polymer-coated urea did not show any effect on reducing denitrification losses and N2. emissions in terms of percentage of applied N. As temperature gradually decreased from transplanting to harvest, denitrification rates and N2. emissions tended to decrease. A significant （P ≤0.01） positive correlation occurred between denitrification （r = 0.872. or N2. emission （r = 0.781） flux densities and {2. temperature in the CK treatment with a stable nitrate content during the whole growing season.

关键词： denitrification loss N2. emission polymer-coated urea urea vegetable field

Estimation of Sand Transportation Rate for Fixed and Semi-Fixed Dunes Using Meteorological Wind Data

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Pedosphere 2009年第1期19卷 129-136页

作者： HU Xia LIU Lian-You LI Shun-Jiang XIAO Bi-Lin LIU Mu-Xin key Lab of Environment Change and Natural Disaster Ministry of Education Beijing Normal Univeristy Beijing 100875 （China） academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs/Ministry of Education Beijing Normal University Beijing 100875 （China） state key {2. of soil and Sustainable agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 21008 （China） institute of plant {2. and Resources Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 （China） institute of agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 （China）

Taibus County, Inner Mongolia, china, lies in a farming-pastoral ecotone, where severe wind erosion and various aeolian sand hazards are prevalent and fixed and semi-fixed sand dunes occur frequently. This study was conducted to investigate the relationships between sand transportation rate and wind speed for the fixed and semi-fixed sand dunes based on field measurements. The annual quantity of soil erosion by wind was estimated using meteorological wind data. The results indicated that the sand transportation rate in Taibus County in 2.00 was 57.38 kg cm-1 year-1 for the semi-fixed dunes and 4.56 kg cm-1 year-1 for the fixed dunes. The total duration of erosive winds covered 12.5% of the time of the year, and spring posed the highest potential of sand transportation. Wind with low speed (≤ 17 m s-1) and high frequency plays a dominant role in sand transportation, while strong wind (≥ 17 m s-1) with low frequency significantly enhanced the sand transportation. Erosive wind speed, directions, and frequency were three crucial dynamic factors influencing sand hazards in the farming-pastoral ecotone. The dominant factors intensifying sand and dust storms in Taibus County might be related to the favorable wind condition in combination with the durable drought, which led to land desertification and vegetation degradation.

关键词： fixed and semi-fixed dunes meteorological wind data sand transportation rate wind erosion

Cotton bollworm resistance to Bt transgenic cotton: A case analysis

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Science china(Life sciences) 2010年第8期53卷 934-941页

作者： LIU ChenXi, LI YunHe, GAO YuLin, NING ChangMing & WU KongMing state key {2. of plant Disease and Insect Pests, institute of plant Protection, chinese academy of agricultural Science, beijing 100193, china state key {2. of plant Disease and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Science Beijing China

Cotton bollworm (Helicoverpa armigera) is one of the most serious insect pests of cotton. Transgenic cotton expressing Cry toxins derived from a soil bacterium, Bacillus thuringiensis (Bt), has been produced to target this pest. Bt cotton has been widely planted around the world, and this has resulted in efficient control of bollworm populations with reduced use of synthetic insecticides. However, evolution of resistance by this pest threatens the continued success of Bt cotton. To date, no field populations of bollworm have evolved significant levels of resistance; however, several {2.-selected Cry-resistant strains of H. armigera have been obtained, which suggests that bollworm has the capacity to evolve resistance to Bt. The development of resistance to Bt is of great concern, and there is a vast body of research in this area aimed at ensuring the continued success of Bt cotton. Here, we review studies on the evolution of Bt resistance in H. armigera, focusing on the biochemical and molecular basis of Bt resistance. We also discuss resistance management strategies, and monitoring programs implemented in china, Australia, and India.

关键词： Helicoverpa armigera Bt resistance transgenic cotton resistance mechanism management strategies

Response of Rice Varieties to Bound Residues of Metsulfuron-Methyl in a Paddy soil

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Pedosphere 2007年第4期17卷 487-492页

作者： LI Zhao-Jun WANG Hai-Zhen XU Jian-Ming WU Jian-Jun MA Guo-Rui institute of soil and Water Resources and Environmental Science Zhejiang University Hangzhou 310029 （China）. institute of agricultural Resources and Regional Planning Ministry of Agriculture Key Laboratory of Plant Nutrition and Nutrient Cycling Chinese Academy of Agricultural Sciences Beijing 100081 （China）

Metsulfuron-methyl is one of the widely used sulfonylurea herbicides. However, approximately half of the applied metsulfuron-methyl may remain as bound residues in soil. To characterize the response of rice plants to residual metsulfuron-methyl in soil, the activities of acetolactate synthase （ALS）, superoxide dismutase （SOD）, peroxidase （POD）, and catalase （CAT） were investigated in two rice varieties that differed in susceptibility to the herbicide. Changes in the activity of these enzymes in leaves and roots of Xiushui 63, a sensitive rice variety, were greater than those in a resistant variety Zhenong 952. Irrespective of variety, changes in the enzyme activity were greater in the roots than in the leaves. The activities of ALS and CAT decreased, while the SOD activity increased with the increase in the amounts of bound residues of metsulfuron-methyl （BRM） in soil. The POD activity increased at the BRM level of 0.02. mg kg^-1, but decreased at the BRM level of 0.05 mg kg^-1. The results showed that the bound residues of sulfonylurea herbicides may affect metabolism of rice plants.

关键词： ALS activity bound residues CAT activity metsulfuron-methyl SOD activity

Invasive mechanism and control strategy of Ageratina adenophora (Sprengel)

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Science china(Life sciences) 2010年第11期53卷 1291-1298页

作者： WAN FangHao1, LIU WanXue1, GUO JianYing1, QIANG Sheng2. LI BaoPing2. WANG JinJun3, YANG GuoQing1, NIU HongBang1, GUI FuRong1, HUANG WenKun1, JIANG ZhiLin1 & WANG WenQi3 1state key {2. for Biology of plant Diseases and Insect Pests, institute of plant Protection, chinese academy of agricultural sciences, beijing 100193, china 2.ollege of plant Protection, Nanjing agricultural University, Nanjing 2.0095, china 3key {2. of Entomology and Pest Control Engineering, College of plant Protection, Southwest University, Chongqing 400716, china state key {2. for Biology of plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing China College of plant Protection Nanjing Agricultural University Nanjing China key laboratory of Entomology and Pest Control Engineering College of Plant Protection Southwest University Chongqing China

In order to ascertain the invasive mechanism and control strategy of the invasive Crofton weed, Ageratina adenophora, its ecological adaptability and population differentiation,the formation of single dominant population, displacement of native plants and sustainable management strategies were investigated. The present results helped to clarify and explain such issues as the adaptability post invasion,interaction and competition between inter-and intra-species and community resistance, thereby providing important references to researches on other invasive alien species.

关键词： Ageratina adenophora invasive mechanism genetic diversity ecological adaptation allelopathy feedback of soil biota competitive displacement

Profile Characteristics and Potential EnvironmentalEffect of Accumulated Phosphorusin soils ofVegetable Fields in Beliing

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Pedosphere 2002年第2期12卷 179-184页

作者： SU DECHUN, YANG FENHE and ZHANG FUSUODepartment of plant nutrition,{2. agricultural University, beijing 100094 (china) Department of plant nutrition China Agricultural University 北京 100094

Profile characteristics of accumulated P in 10 representativesoils of vegetable fields in suburban districts of beijing wereinvestigated. Bioavailability of the accumulated P and its potentialeffect n the environment were studied in a greenhouse pot experimentand a soil column experiment. The results showed that theconcentration of Olsen-P in the 0～2. cm soil samples of thevegetable fields ranged from 2.1 to 358.0 mg kg^-1, which was 2.to 10times higher than that of the crop field sin the suburbs of *** of the excessive phosphorus was accumulated in the topsoils.

关键词： accumulated P bioavailability environment vegetable fields

控制棉铃虫猖獗危害的区域性综合防治关键技术体系的研究

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中国农业科学 1995年第1期 1-7页

作者： Cotton Insect research Group(institute of {2. Protection, chinese Acadmy of agricultural sciences,beijing 100094) 中国农业科学院植物保护研究所

在跟踪推广应用“六五”以来所形成的综防技术基础上，进一步研究改进关键技术、加强病虫监测预报、组建综防技术体系，在１９９２、１９９３年棉铃虫猖獗发生的情况下，于河南省新乡棉花病虫害综防示范区０．６７万ｈｍ２棉田上实施后... 详细信息

在跟踪推广应用“六五”以来所形成的综防技术基础上，进一步研究改进关键技术、加强病虫监测预报、组建综防技术体系，在１９９２、１９９３年棉铃虫猖獗发生的情况下，于河南省新乡棉花病虫害综防示范区０．６７万ｈｍ２棉田上实施后，有效控制了棉铃虫危害。这套控制棉铃虫猖獗危害综合防治关键技术主要是：研究改进了棉铃虫中期预报方法；提出“一代监测、二代保顶、三代保蕾、四代保铃”为主的防治策略；制定推广适用于不同世代、不同水肥条件的科学防治指标；协调应用多种配套措施保护、利用自然天敌控害；系统监测和治理害虫抗药性；利用棉花种质资源和品种的抗病虫性；诱杀成虫；组建大面积综防技术体系。

关键词：棉铃虫猖獗危害综合防治关键技术区域性综防技术体系

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中国菌根研究60年：过去、现在和将来

中国科学：生命科学 2012年第12期42卷 431-454页

作者：何新华段英华陈应龙徐明岗云南师范大学生命科学学院昆明650092 中国农业科学院农业资源与农业区划研究所农业部作物营养与施肥重点开放实验室北京100081 state Centre of Excellence for Ecohydrology School of Natural ResourcesEdith Cowan UniversityJoondalupWA 6027 School of plant Biology University of Western AustraliaCrawleyWA 6009Australia School of Earth and Environment University of Westem AustraliaCrawleyWA 6009Australia

菌根(真菌根系)存在于大约90%的植物中,在促进土壤结构、植物养分与生长、元素生物地球化学循环和陆地生态系统结构与功能等方面具有重要作用.过去60年尤其是近30年,中国菌根研究成果举世瞩目,如共鉴定出2.种新种与12.余种新记录种丛枝... 详细信息

菌根(真菌根系)存在于大约90%的植物中,在促进土壤结构、植物养分与生长、元素生物地球化学循环和陆地生态系统结构与功能等方面具有重要作用.过去60年尤其是近30年,中国菌根研究成果举世瞩目,如共鉴定出2.种新种与12.余种新记录种丛枝菌根真菌、30种新种与800余种新记录种外生菌根真菌以及10种新种与100余种新记录种兰花菌根真菌.同时,在菌根真菌菌种丰富度与遗传结构、菌种生态分布与植物种群,植物养分摄取与生长、植物修复与土地复垦、植物抗病性和与其他土壤微生物相互作用、菌根植物酶学性质及大气CO2.O3浓度升高对丛枝菌根多样性的影响等方面也取得重大进展.本文选介中国菌根主要研究成就,进行研究前景展望,以促进我国菌根研究的深入开展.

关键词：中国丛枝菌根外生菌根兰花菌根菌根生理和生态功能植物修复物种多样性国际合作