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. Locoweed is one of main poisonous plants in the world, and also is the most important toxic plant in grassland of China. The distribution range of the locoweed is extending continuously and it has formed or is coming into dominant species gradually in some areas in recent years, which cause the retrogressive succession and grazer poisoning and died in rangeland. Locoweed seriously threatened the grassland agriculture and cure practice to the locoweed for more than ten years, this paper reviewed the present situation and prospect of the studies on the locoweed in China, which include the researches of it's biological characteristics, distribution, ecological environment, harmfulness, prevention, weeding, utilization and ecological control etc. 相似文献
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桑蓟马种群动态,抽样技术及危害指标研究 总被引:1,自引:0,他引:1
本文对桑蓟马种群时、空动态及危害指标进行了研究。结果表明:桑蓟马在田间呈聚集分布,虫口密度持续增长,高峰虫量叶随叶位上升而上升,具显著的分层危害特点。在此基础上讨论了该虫的抽样技术,给出了理论抽样公式和防治阈值确定上序贯抽样的应用实例。首次提出了危害指数的概念和计算公式并进行了初步验证。 相似文献
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提出了黄脊竹蝗界标准的危害程度。在饲养观察的基础上,初步确定了黄脊竹蝗的监测预警技术指标,并就发布各虫期(态)发生趋势预报的相关问题提出了建议。 相似文献
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阐述了危险废物产生现状和危害,讨论了几种常用处理与处置方法,并比较了各种方法优缺点和适用性.在上述讨论基础上,指出了危险废物焚烧处置技术是未来发展的主流趋势. 相似文献
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