立地条件对毛竹林枯梢病感病指数的关系效应研究

[目的]研究毛竹林的立地条件和枯梢病发生的关系。[方法]对江西省不同立地条件的60块毛竹样地开展了监测调查,分析了坡度、坡位、坡向、海拔高度和土壤层厚度5个立地因子对毛竹林枯梢病感病指数的影响。[结果]表明,毛竹枯梢病的感病指数在不同坡度、不同海拔、不同土层厚度下均存在极显著的差异,且感病指数与坡度及海拔高度呈极显著正相关关系,与土层厚度呈极显著负相关关系;感病指数与坡向呈负相关关系;坡位对毛竹枯梢病的感病指数无显著影响。同时,为了探究这5个立地因子对毛竹枯梢病感病指数的综合影响,利用数量化理论,以这5个立地条件为自变量,毛竹枯梢病的感病指数为因变量,建立多元线性回归预测方程,该预测方程复相关系数R=0.854,复相关系数的F检验得F=10.432F_(0.01)(11.48)=2.64,经T检验,与毛竹枯梢病感病指数关系最大的立地因子是土层厚度,其次是海拔高度和坡度,这3个因子是影响毛竹枯梢病的主导因子。[结论]综合分析得出,在急险坡、上坡位、阳坡面、高海拔、薄土层的立地条件下,毛竹枯梢病的感病指数最大;在平缓坡、下坡位、阴坡面、丘原、肥土层的立地条件下,毛竹枯梢病的感病指数最小。

Study on the Relationship between Site Conditions and Phyllostachys heterocycla Disease Index

[Objective] To study the relationship between site conditions and Phyllostachys heterocycla disease index.[Method] A monitoring survey was conducted on 60 Ph. heterocycla sample plots with different site conditions in Jiangxi Province, and the effects of five site factors (slope, slope position, slope direction, altitude and soil thickness) on the disease index for Ph. heterocycla were analyzed.[Results]The results showed that there was a certain correlation between the five factors and the disease index of Ph. heterocycla. The disease index was significantly different under different conditions of slope, elevation and soil thickness. The disease index was positively related with the slope and altitude, and negatively related with soil thickness. There was no significant difference on the disease index under different slop conditions, but a weak negative relation was observed. The slope position also had no significant impact on the disease index of Ph. heterocycla. In the meantime, in order to explore the comprehensive effects of the five site condition factors on the disease index of Ph. heterocycla, a multivariate linear regression prediction equation was established by using the quantitative theory, with the five site condition factors were taken as independent variables, and the disease index was taken as dependent variables. The prediction equation''s R=0.854, F=10.432 > F_0.01(11.48)=2.64. Also, it was found by T test that altitude and soil thickness were the most two significant factors affecting the disease index.[Conclusion] It is concluded that the value of disease index of Ph. heterocycla is the highest under the site conditions of steep slope, upper slope, sunny slope, high altitude and thin soil layer, and the value is the lowest under the conditions of flat and gentle slope, downhill position, shady slope, hilly land and fertilizer soil.