【摘要】 本文根据36块田的调查,用种群空间格局参数I、C_A、I_δ、m~*/m和α、β值进行分析,稻根象甲幼虫和(?)≥0.6头/样方(每样方为0.5m~2)的成虫种群,在稻田均属具公共k值的负二项分布;(?)<0.6头/样方的成虫种群则为随机分布。成虫聚块的大小和面积与平均密度有关。低密度时种群的聚集主要由于环境的异质性;高密度时种群的聚集则由本身的行为习性所致。随着耕作强度的增加,幼虫种群的聚集度和越冬死亡率增大。更多还原

【Abstract】 Samples of Echinocnernus squameus from 36 paddy fields are analyzed to determine its population spatial pattern in terms of pattern parameters I,C_A,I_δ,m~*/m, α and β. A negative binomial distribution with common k values is shown for both larvae and adults when the average density of adults ≥0.6 head per quadrat (1 quadrat=0.5m~2) and a complete randomness is found for adults when <0.6 head per quadrat. The dynamics of adult patchiness, such as patch size and occupied area, seems to be related with average density. The population aggregation is influenced by environmental heterogeneity when the average density is low, but mainly determined by its own behavioral custom when the density is relatively high. The aggregation intensity of larvae population and the overwintering mortality will increase with increasing intensity of tillage.更多还原