人工林赤腹松鼠危害程度与生境因子的关系研究

2009年3～6月,采用样方法对四川省洪雅县人工林赤腹松鼠危害相关的生境因子进行了调查。共设置了240个样方。样方调查中记录了2个反应危害等级的变量(危害株数和乔木总数)和11个生境变量(森林类型、海拔、坡向、坡度、坡位、距最近道路距离、距最近水源距离、乔木均高、乔木平均胸围、灌木盖度和草本盖度)。通过广义线性模型研究这些因子与人工林赤腹松鼠危害程度的关系。结果显示,赤腹松鼠危害程度与森林类型、坡度、坡向、乔木平均胸围呈显著性相关,与其他因子无显著相关性,在柳杉-杉木林中的危害高于纯柳杉林,在阴坡的危害低于其他坡向,危害程度随坡度和乔木平均胸围的增加而增加。

Study on the Relationship between the Disturbance Degree of Planted Forest by Red-bellied Squirrels and its Habitat Factors

Habitat factors related to the infection by red-bellied squirrel Callosciurus erythraeus were investigated in planted forest of Hongya county, Sichuan province, from March to June, 2008. A total of 240 plots were designed. Two factors related to the degree of the disturbance (the number of the disturbed trees and the total number of the trees in the plot) were recorded. Eleven factors associated with habitat were measured, which included types of planted forest, altitude, slope direction, slope gradient, slope location, distance to the nearest road, distance to the nearest water, tree average height, tree average perimeter, shrub cover and grass cover. A generalized linear model was used to analyze the relationship between those factors and disturbance degree of the red-bellied squirrel. The results showed that the disturbance degree was significantly correlated to the type of planted trees, the slope gradient, the slope direction, and the average perimeter of trees. The squirrels disturbed the Crypotomeria fortunei-Cunninghami lanceolata forests more severe than the Crypotomeria fortunei forests. The disturbance degree was increased as the increase of slope gradient and the average perimeter of the trees. However, the disturbance degree was lower in shady slope than in other slopes.