大袋蛾种群数量动态的研究

Study on the Population Dynamics of Clania variegata Snellen

大袋蛾ＣｌａｎｉａｖａｒｉｅｇａｔａＳｎｅｌｅｎ在我省一年１代，少数年份有二代分化。雌性比每年有差异。４龄前种群年龄组成较为复杂，种群数量增长为离散性，Ｎｔ＋１＝ＲｏＮｔ。影响种群数量变动的因子主要是气候和天敌：与１月份和全年的平均温度相关极显著；与５、６月份的温湿系数相关极显著；与全年的降雨量相关显著；种群数量变动与林型、树种无关。天敌因素对种群数量的影响是无天敌状况下的２．

Clania variegata Snellen has one generation each year but differentiation of two generations occationally.The female sex rate is different in different years.The age composition of population before the 4th instar is complicated.The population increases in the divergent form.The main factors affecting population quantity are climate and natural enemies.The population quantity has a great significance not only to the mean temperatures of both January and the whole year but to the hygrothermal coefficient in May and June.The quantity has no significance to forest type and tree species.The influcnce of natural enemies on population quantity is 2.96 times as much as that of no natural enemies.