1、2代不同林龄马尾松人工林土壤微量元素及酶活性

摘要

Through the pairing plot method with different ages (8,9,15,18,20 years) and generations (first and second),the soil available microelements and enzyme activities were investigated in 0-20 cm and ＞20-40 cm of first and second generation Masson pine plantations.The results showed:After successive planting,the soil available microelement contents in the young forest will increase to some extent,and there is significant difference (P＜0.05) for the soil available Mn content between the first and second generations.The soil available Fe,Cu and Zn contents are on the rise in the middle aged forest,but the available Mn content is on the downtrend.There is significant difference (P＜0.05) for the soil available Fe and Cu contents between the first and second generations.After successive planting,the contents of the urease,protease,phosphatase,catalase and polyphenoloxidase activities of the second generation in the young growth and middle aged forest at the same soil layer are higher than those in the first generation.Between the first and the second generations,there is significant difference (P＜0.05) for the soil protease and phosphatase in 0-20 cm,the urease and catalase in 0-20 cm and ＞20-40 cm of the young forest,as well as for the soil protease,phosphatase and polyphenoloxidase activities in 0-20 cm,and the soil urease,phosphatase,catalase and polyphenoloxidase activities in ＞20-40 cm of the middle aged forest.From the different soil layer,the soil available Fe,Mn,Cu,Zn contents and the soil enzyme activities in the same young and middle aged generation show the downtrend in different degrees with the depth increase of soil layer.There is difference of the same generation and the same soil layer in the young and middle aged forests.%采用配对样地法,以不同发育阶段(8、15、18、20 a)的1、2代马尾松人工林为研究对象,对1、2代不同林龄马尾松(Pinus massoniana Lamb.)人工林0～20 cm和＞20～40 cm土层土壤有效微量元素及酶活性进行了比较分析.结果表明:连栽后,幼龄林土壤中有效微量元素质量分数均不同程度的上升且有效态Mn质量分数在1、2代间差异显著(P＜0.05);中龄林土壤有效Fe、Cu、Zn质量分数均呈上升趋势,而有效Mn质量分数呈下降趋势,且有效Fe、Cu质量分数在1、2代间差异显著(P＜0.05).连栽后,幼龄林、中龄林相同层次土壤脲酶、蛋白酶、磷酸酶、过氧化氢酶和多酚氧化酶活性2代均高于l代,且幼龄林O ～ 20 cm土层土壤蛋白酶、磷酸酶和2层次土壤脲酶、过氧化氢酶、中龄林0 ～ 20 cm土壤蛋白酶、磷酸酶、多酚氧化酶和＞20 ～ 40 cm土壤脲酶、磷酸酶、过氧化氢酶、多酚氧化酶活性在1、2代间差异显著(P＜0.05).从不同土壤层次看,土壤有效Fe、Mn、Cu、Zn质量分数以及土壤各种酶活性在同代幼龄林、中龄林中总体表现出随土层深度增加呈不同程度的下降趋势,同时在同代相同土壤层次的幼龄林、中龄林中也存在一定差异.