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林业害虫美国白蛾的识别与防治措施分析
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作者 杜海平 《种子世界》 2020年第12期106-107,共2页
美国白蛾自传入中国以来,对我国多个省区市造成了较大的危害,防治难度较大,严重影响到了群众的生产生活,并且还有继续蔓延的趋势。本文通过调查与分析文献资料以及以工作中的实践经验为基础,从美国白蛾的识别、监测预报以及防治方法等... 美国白蛾自传入中国以来,对我国多个省区市造成了较大的危害,防治难度较大,严重影响到了群众的生产生活,并且还有继续蔓延的趋势。本文通过调查与分析文献资料以及以工作中的实践经验为基础,从美国白蛾的识别、监测预报以及防治方法等各个方面进行了较为详细的分析,旨在能对广大的林业工作者以及林农能有所帮助,以便能最大限度地降低美国白蛾所带来的危害。 展开更多
关键词 林叶害虫 美国白蛾 识别与防治
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Investigation on Effect of Forestation by Mixing Pinus massoniana with Schima superba
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作者 HUANGWenchao HUANGLili 《Chinese Forestry Science and Technology》 2004年第2期26-33,共8页
Since forestation of pure forest of Pinus massoniana is liable to suffer from pest calamity, soilerosion, decrease of soil fertility, and difficulty in wood production in the hilly areas of southern China, weconducted... Since forestation of pure forest of Pinus massoniana is liable to suffer from pest calamity, soilerosion, decrease of soil fertility, and difficulty in wood production in the hilly areas of southern China, weconducted an investigation on the three types of forests in Gaoan County of Jiangxi Province, namely, thepure forest of Pinus massoniana, the pure forest of Schima superba, and the mixed forest consisting of thetwo species, setting up standard stand, measuring and studying the growing stock, biomass, leaf area, roots,soil, vegetation, pests, litters, soil erosion, microclimate, etc., with the following results. ① The averageheight, diameter at chest height, and volume of the mixed forest are higher than those of the pure forest ofPinus massoniana by 30.9%, 31.7% and 10.6%, respectively. ② The biomass of the mixed forest is 2.24times as much as that of the pure forest of Pinus massoniana. ③ The litters of the mixed forest is 3.37 timesand 1.96 times as much as the litters of the pure forest of Pinus massoniana and the pure forest of Schimasuperba respectively. ④ The occurrence of pest calamity per tree is lower and the conditions of soil erosionand microclimate are better than those of the pure forest of Pinus massoniana. ⑤ The mixed forest of the twospecies is an excellent mixed type of needle-leaf and deciduous forest worth being popularized in Chinassubtropical areas, especially in the low hilly areas. It is recommended in plantation that the mixed patterns bebetween trees, lines, small blocks, or scattered-dots, the ratio of mixture of Pinus massoniana and Schimasuperba be 5 to 1, or 3 to 1, and the initial space between trees be 1.2, 1.5, or 2.0 m while the initial densitybe 6 944 to 4 440 trees per square hectare. 展开更多
关键词 Pinus massoniana Schima superba mixed forest effect of forestation
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