云杉花墨天牛与褐梗天牛在寄主红松上的生态位分布

Niche distribution of Monochamus saltuarius and Arhopalus rusticus onhost Pinus koraiensis

【目的】从垂直空间角度,明确云杉花墨天牛Monochamus saltuarius和褐梗天牛Arhopalus rusticus在红松Pinus koraiensis上的空间分布,探索这2种天牛的种间关系,为其防治措施提供理论基础。【方法】在辽宁抚顺的红松P.koraiensis林中同时监测到云杉花墨天牛与褐梗天牛成虫,且在同一株红松上能发现这2种天牛幼虫。以红松作为天牛幼虫的栖息资源,以红松的垂直高度作为资源序列,选取受天牛危害的红松立木,以40 cm为单位,研究云杉花墨天牛与褐梗天牛幼虫的形态学特征、在红松受害木上的分布位置、生态位宽度及生态位重叠度。【结果】云杉花墨天牛幼虫在红松上的分布为(87.20±8.45)头·株^(−1),褐梗天牛幼虫在红松上的分布为(24.40±2.37)头·株^(−1)。云杉花墨天牛幼虫在红松上呈正偏态分布,地上80~120 cm处分布最多,为(16.40±2.38)头·株^(−1),显著高于80 cm以下及120 cm以上高度的幼虫数量(P<0.05);褐梗天牛幼虫在红松受害木地上部分均匀分布,200~280 cm高度处数量最多,占总体幼虫数量的33.63%,显著高于120 cm以下、160~200 cm及320 cm以上的幼虫数(P<0.05);在红松受害木地下部分均未发现这2种害虫的幼虫。云杉花墨天牛幼虫和褐梗天牛幼虫的生态位宽度有一定差异,分别为0.6944和0.7576,生态位重叠指数为0.8046。【结论】云杉花墨天牛幼虫主要分布在红松树干中下部,褐梗天牛幼虫在红松树干各高度上均匀分布,两者在红松上生态位重叠较高,生态特性相似程度较高,一定程度上表明两者在红松林内有较高竞争关系。

[Objective]This study aims to clarify the spatial distribution of Monochamus saltuarius and Arhopalus rusticus on Pinus koraiensis from the perspective of vertical space,and explore the interspecific relationship between these two species,so as to provide theoretical basis for their control measures.[Method]Adults of M.saltuarius and A.rusticus were simultaneously detected in P.koraiensis forest in Fushun,Liaoning Province,and both species of beetle larvae were found on the same P.koraiensis tree.Taking P.koraiensis as the habitat resource of longhorn beetle larvae and the vertical height of P.koraiensis as the resource sequence,P.koraiensis affected by longhorn beetles was selected using 40 cm as a unit to study the morphological characteristics,distribution location,niche width and niche overlap of M.saltuarius and A.rusticus larvae.[Result]The distribution of M.saltuarius larvae on P.koraiensis was(87.20±8.45)heads per plant,and that of A.rusticus larvae was(24.40±2.37)heads per plant.The distribution of M.saltuarius larvae was positively skewed on P.koraiensis,with the largest distribution of(16.40±2.38)heads per plant at 80−120 cm above ground,significantly higher than the number below 80 cm and above 120 cm(P<0.05).A.rusticus larvae were evenly distributed in the aboveground parts of the affected trees,with the most abundant at a height of 200−280 cm,accounting for 33.63%of the total number of larvae,significantly higher than the number below 120 cm,160−200 cm and above 320 cm(P<0.05).No larvae of these two pests were found in the underground parts of damaged P.koraiensis.There was a certain difference in niche width between M.saltuarius and A.rusticus larvae,with values of 0.6944 and 0.7576,respectively,and a niche overlap value of 0.8046.[Conclusion]M.saltuarius larvae are mainly distributed in the middle and lower parts of the trunk of P.koraiensis,while A.rusticus larvae are evenly distributed at various heights of the trunk.The ecological niche overlap between the two is relatively high on P.koraiensis,and the degree of similarity in ecological characteristics is relatively high,indicating a high competitive relationship between the two in P.koraiensis forest to a certain extent.