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稻飞虱综合防治试验示范
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作者 陈明贵 胡贵棋 +2 位作者 陈正刚 李照荣 马强伦 《贵州农业科学》 CAS 1999年第S1期45-46,共2页
在水稻生长季节对稻飞虱和天敌发生动态进行调查,指导合理用药。综防区施1次药和化防区施3~4次药产值相差不大,综防区降低防治费用17元/667m2,保护了天敌。杀螟虱和扑虱灵两药剂对稻飞虱天敌系统具有较高选择性,是目前... 在水稻生长季节对稻飞虱和天敌发生动态进行调查,指导合理用药。综防区施1次药和化防区施3~4次药产值相差不大,综防区降低防治费用17元/667m2,保护了天敌。杀螟虱和扑虱灵两药剂对稻飞虱天敌系统具有较高选择性,是目前生产上防治飞虱的理想农药。 展开更多
关键词 天敌保护 防区 化防区 农药选择
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德军空地导弹系统概览 被引量:1
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作者 朱爱平 马凌 《飞航导弹》 北大核心 2011年第4期75-78,共4页
概述了德国空地武器系统的发展现状,重点介绍了德国空军的旋风战斗机和欧洲战斗机所携带的在役武器,并对其空地武器系统的未来发展做出了预测。
关键词 德国空军 空地武器系统 模块化防区外武器 精确激光制导武器
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The Three-North Shelterbelt Program and Dynamic Changes in Vegetation Cover 被引量:9
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作者 王强 张勃 +2 位作者 张志强 张喜风 戴声佩 《Journal of Resources and Ecology》 CSCD 2014年第1期53-59,共7页
The Shelterbelt Forest System Program in northeast, north and northwest China (the Three-North Shelterbelt Program, TNSP) is the largest ecological reforestation program in the world. TNSP vegetation research has im... The Shelterbelt Forest System Program in northeast, north and northwest China (the Three-North Shelterbelt Program, TNSP) is the largest ecological reforestation program in the world. TNSP vegetation research has important ecological meaning and profound social and economic signiifcance. Here, spatio-temporal variation in vegetation cover under the TNSP was examined using the NDVI average method, major climatic factors such as temperature and precipitation, and linear regression trend analysis from 1982 to 2006. We found that in the past 25 years, NDVI vegetation in the study area has consistently risen at a rate of 0.007 per decade. Vegetation cover, temperature and precipitation are positively correlated. The area of vegetation associated with precipitation is larger than the area related to temperature;precipitation is the key factor affecting vegetation growth across the TNSP. From 1982 to 2006, regions with improved vegetation cover were found in the central and southern part of the Greater Khingan Mountains, central part of the Lesser Khingan Mountains, northeastern part of the Changbai Mountains, Yanshan Mountians, Western Liaoning Hilly Region, Altai Mountains, Tien Shan Mountains, eastern part of the Qilian Mountains, eastern part of the northwest desert as wel as southern part of the Gul y Region of the Loess Plateau. However, vegetation cover declined on both sides of the Greater Khingan Mountains, western part of the Hulun Buir Plateau, northern part of the Sanjiang Plain, southern part of Horqin Sandy Land, southern part of the northwest desert and northern part of the Gul y Region of the Loess Plateau. 展开更多
关键词 NDVI Three-North Shelterbelt Program (TNSP) spatio-temporal changes correlation analysis dynamic study northern China
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