杨树蛀干害虫空间格局的研究

A Research on Space Distribution Pattern of Poplar Stem Borer

杨树蛀干害虫 (黄斑星天牛与光肩星天牛 )在林间水平格局为聚集型分布 ;垂直方向用 Weibull分布拟合。平均虫口密度与杨树树干的高度与直径都有密切的关系 ,其与树干高度的关系可用 y=3.481 5 + 0 .5 30 5 x - 0 .0 85 4x2表示 ,危害最严重部位在3.1 0 6 7m高处 ;其与树干直径的关系可用 y=- 4 .7896 + 1 .0 5 37x - 0 .0 36

The space distribution pattern is considered as aggregated one on horiyonal,itfits Weibull distribution on perpendicular in natural environment.The everage population densi- ty of the borer is closely related to the height and diameter of the poplar trunk.Relationship between the population and trunk height can be depicted as y=3.481 5 + 0 .5 30 5 x - 0 .0 85 4x2 .The worst harmedsit is atthe heiht of 3.1 0 6 7meters,and its relationship with di- ameter of trunk can be discribed as y=- 4 .7896 + 1 .0 5 37x- 0 .0 36 9x2 .