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一、森林病害的发生与环境的关系害虫的发生与周围环境有着密切的联系,环境条件适合于害虫生长发育时,害虫数量就显著增长,因而形成灾害。否则害虫数量就减少,灾害不易形成。因此,根据环境条件变化情况预测害虫数量的上升或下降,以便决定是否需要进行防治工作。影响害虫种群数量变动的环境因子可分为非生物因子和生物因子两类。非生物因子对害虫的影响: 1、温度昆虫是变温动物,其体温随环境温度而异。温度在很大程度上决定害虫的发
First, the relationship between the occurrence of forest diseases and the environment The occurrence of pests and the surrounding environment are closely linked to the environmental conditions suitable for the growth and development of pests, the number of pests increased significantly, resulting in disasters. Otherwise, the number of pests will be reduced and disasters will not form easily. Therefore, the increase or decrease in the number of pests is predicted based on changes in environmental conditions in order to decide whether or not prevention and control work is required. Environmental factors that affect the number of pest populations can be divided into two categories of non-biological factors and biological factors. Non-biological factors on the impact of pests: 1, the temperature Insect is a variable temperature animal, its temperature varies with the ambient temperature. The temperature determines to a large extent the pest’s hair