重建森林对退化红壤土壤酶特性影响

以地处赣中吉泰盆地的泰和县严重退化红壤区为研究对象 ,1991年采取不同模式重建森林 ,2 0 0 1年选择 8种不同重建模式测定土壤蔗糖酶、蛋白酶、脲酶、过氧化氢酶、酸性磷酸酶活性 ,研究表明 :(1)用主成分分析排序 (PCA)可将 8种模式重建的森林土壤酶活性分为 3类 ,枫香纯林及其与针叶树种的混交林模式是酶活性最高的一类 ,针叶纯林模式土壤酶活性最低的一类 ;(2 )土壤各种酶活性总的垂直分布规律是自上而下逐渐减弱 ,但不同种类的酶、不同重建类型 (阔叶林、针叶林、针阔混交林 )变化幅度有明显差异 ,且蔗糖酶以阔叶林变异幅度最大 ;(3)脲酶活性两季节 (5月和 10月 )差异最大 ,蛋白酶季节差异最小。

A Study on Soil Enzyme Characteristics of Rehabilitated Forest in Seriously Eroded Quarternary Red Clay Region

This paper takes seriously eroded red soil region located in Taihe County of Jiangxi Province as the object of the study . In 2001, according to the studies on the activity of 5 soil enzymes(proteinase, urease, sucrase, catalase and acid phosphatase) of the forest rehabilitated in different models in 1991, (1) the soil enzyme activity of the rehabilitated forests in 8 models can be divided into 3 groups by PCA; (2)all of the 5 enzymes' activity decline step by step with the increase of soil depth, but the degrees have obvious difference among different enzymes and among different rehabilitated forests; the greatest variance of sucrase enzyme activity among the soils at different depths is the soil of the broadleaved forest, the variance of urease activity of the broadleaved forest soil and mixed forest soil is greater than that of the conifers forest, and the variance of catalase activity of all kinds of forests is more accordant than that of other enzymes; (3)in seasonal variance of soil enzyme activity, urease activity has the greatest variance with an average of 62.32%, and proteinase activity has the smallest variance with an average of 13.04%; (4)the relationship between soil enzyme activity and microbial characteristics is obvious, espeacially the relationship between soil respiratory intensity and the activity of the 5 enzymes, which is extreme.