人工林物种多样性与害虫的控制

根据国内外的最新研究成果,从人工林害虫可持续控制的需求出发,对利用物种多样性与系统稳定性控制虫害的可能性、人工林物种多样性与害虫控制的关系及其内在作用机制、天然林与人工林在抑制虫害能力上的差别进行综述,分析人工林植物物种多样性与昆虫物种多样性对害虫控制的影响,认为植物物种多样性主要从植食性昆虫搜寻寄主植物,植物营养的差异对植食性昆虫取食和发育的影响,及种类组成不同的植物群落中植食性昆虫天敌数量的变化3个方面影响害虫的发生;要通过调节植物群落中昆虫物种的多样性影响目标害虫的种群数量,既要维护其天敌类群的稳定,也要使与害虫处于同一营养层次的其他植食性昆虫有足够的多样性,甚至也要保护和利用中性、中位及顶位昆虫.对人工林害虫的控制,可借鉴天然林自控虫害的原理,采用生态育林、封山育林及生物技术措施,逐步调整林分的结构,提高其物种多样性,增强林分自身的抗虫能力.

The Relation of Species Diversity to Pest Control in Forest Plantations

The latest results, from both domestic and foreign research, on the relation of pest abundance and control in forest plantations are analyzed and reviewed. Factors are plant diversity, insect diversity, and their intrinsic function mechanisms. Plant diversity helps control pests when target tree species are dispersed among other species and by increasing overall insect diversity, including natural enemies and competitors of the pests. Compared to tree plantations, natural forest has both higher tree species and insect species diversity and this provides some pest control. Drawing lessons from natural forest, we can adjust the compositions of plantations and secondary forests by adopting eco_silviculture, closing hillsides to allow natural afforestation, and applying biotechnology. All should enhance species diversity and therefore strengthen pest resistance.