摘要
将受害杉木树干视为以lm段为单位的多层次立体结构，以聚集度指标法、频次比较法研究粗鞘双条杉天牛越冬成虫在受害杉木各空间层的空间格局；采用马占山等（1990）重新解释的Taylor幂法则及徐汝梅（1984）改进的Iwao模型研究越冬成虫空间格局的垂直变化规律。结果表明:种群的分布在各空间层均是聚集的，但聚集度随高度上升而增大；分布的基本成分是个体群，个体群数量随高度上升而减少，故防治的重点在树干基部。根据空间分布信息得到了0－1m段调查的理论抽样数，建立了0－1m段平均虫口（x）与整株平均虫口（y）的回归关系：y＝1．4341+1．2541x。
The damaged China fir being regarded as a multiple-stratum structure compsed of 1m stem sections, the spatial distribution Patterns of overwintered adults of (Gressitt) on the damaged China fir trees was studied with the methods of the aggregation index and frequency comparion. The vertical variation among strata was analysed with the Ma Zhanshan's reinterpreted Taylor's Power Low and the Xu Rumei's improved Iwao's Models. It is concluded that the spatial Pattern of overwintered adults on trees is aggregate on every stratum, but the aggregating intensity increases with height. The basic unit of population distribution was individual amss which number decreases with height. According to such a distribution Pattern, we estimted the theoretical sampling numbers and established a regression model between the mean insect density of 0-1m section (x) and the mean insect density of all tree (y), i, e, y=1. 4341+1. 2541x.
出处
《四川农业大学学报》
CSCD
1996年第4期565-570,共6页
Journal of Sichuan Agricultural University
关键词
粗鞘双条杉天牛
越冬成虫
垂直分布
回归估计
SEMANOTUS SINOAUSTER (GRESSITT), OVERWINTERED ADULT
VERTICAL DISTRIBUTION PATTERN
REGRESSION ESTIMATION
FOREST INSECT PESTS
