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一、防护林更新改造的目的与意义防护林可以防风、防寒、防旱、防病、保持水土、改良土壤,对整个地区的生态环境的改变,均有一定的影响。在国内外关于防护林的更新与改造,作为主要研究课题,并已广泛开展研究。徐海垦区,地处我省南端雷州半岛,三面环海,常风频繁,台风大。据近三十年的统计,10级以上的台风,就有20次之多,其中,1971年第9号台风,风力12级,这次台风对橡胶的损失,仅开割树断倒达28.4％。 1973年第13号台风,风力达12级,对橡胶树危害极为严重,据统计,开割树受害三级以上有155415株占9％(内断倒97287株),未开割树受害127335株占
I. Purpose and Significance of Shelterbelt Reconstruction Shelterbelt can prevent wind, cold, drought, disease prevention, maintain soil and water, improve soil, and have a certain impact on the ecological environment in the whole region. At home and abroad on the renovation and renovation of shelterbelt, as the main research topic, and has carried out extensive research. Xu Hai reclamation area, located in the southern tip of our province Leizhou Peninsula, surrounded by the sea, frequent winds, typhoon. According to the statistics of the past three decades, typhoons above Grade 10 have as many as 20 times. Among them, typhoon No. 9 of 1971 and wind power of 12 were used. The typhoon suffered a rubber loss of 28.4 %. Typhoon No. 13 in 1973, with a wind force of 12, posed a serious hazard to the rubber tree. According to statistics, 155415 strains were found to have 9% (Grade 97287), and 127,335 strains of uncut caterpillars