基于冗余分析的降香黄檀人工林叶部病害与土壤因子的关系研究

摘要

In order to explore the correlation between soil variables and Dalbergia odorifera foliage disease,inves-tigation of the diseases and determination of soil factors were made in 13 sample plots in Hainan Province.Redun-dancy analysis (RDA)was used to select dominant factors affecting foliage diseases occurrence on D .odorifera plantations.RDA results indicated that pH,available N,total P and available K were four dominant factors af-fecting the disease.The importance of soil variables was arranged as pH>available N>total P>available K.By clustering analysis,the sample plots were divided into 3 types which were mildly diseased plot,moderately diseased plot and highly diseased plot based on the RDA.The results showed that the correlations between the soil variables and the sample plot with different degree of disease were significantly different.Overall,in highly diseased plot,the content of available N and total P in the soil was highest;the average values were 82.08 mg/kg and 0.68 g/kg.In mildly diseased plot,pH and available K content were highest,the average values were 6.56 and 143.60 mg/kg.%为了探讨降香黄檀人工林土壤因子与叶部病害发生的关系，对海南省13块降香黄檀人工纯林样地进行了病害调查和土壤因子的测定，运用冗余分析找到影响病害发生的主导因子，结果表明：土壤的 pH、速效氮、全磷、速效钾是影响病害发生最主要的4个指标。对病害发生影响的土壤因子按其重要性依次为：pH＞速效氮＞全磷＞速效钾。在冗余分析的基础上，通过聚类分析将样地划分为轻度、中度、重度感病区3种不同类型，并通过单因素方差分析研究了4个主导因子在不同类型样地中的差异。结果表明，不同发病程度的样地与土壤因子相关性差异明显，总体表现为：发病严重的Ⅲ类样地土壤中的速效氮和全磷含量最高，平均值分别为82．08 mg／kg、0．68 g／kg，轻度感病的Ⅰ类样地土壤中的 pH 和速效钾含量最高，平均值分别为6．56、143．60 mg／kg。