千年桐与毛竹凋落叶混合分解对土壤酶活性的影响

在16年生千年桐人工林中按5种分解模式(模式A:千年桐叶100%;模式B:毛竹叶100%;模式C:千年桐叶50%+毛竹叶50%;模式D:千年桐叶75%+毛竹叶25%;模式E:千年桐叶80%+毛竹叶20%)进行千年桐、毛竹凋落叶及其混合分解的野外模拟试验,分析千年桐与毛竹凋落叶混合分解对土壤酶活性的影响及其与凋落物主要营养元素全氮(TN)、全磷(TP)、全钾(TK),微量元素钠(Na)、钙(Ca)、锰(Mn)、镁(Mg)、锌(Zn)及有机碳(OC)的释放量之间的关系.结果表明:5种模式叶凋落物分解1年后TN、TP、TK、OC和Na、Ca、Mn、Mg、Zn的释放量大小并不一致,不同元素释放量在5种分解模式之间均存在显著差异;5种混合分解模式下,蔗糖酶和过氧化氢酶的最强活性区均出现在5～10 cm土层,其中蔗糖酶活性比较为模式E>C>A>CK>D>B,过氧化氢酶活性比较为模式E>CK>B>D>A>C.80%千年桐叶+20%毛竹叶的配比对土壤蔗糖酶和过氧化氢酶活性的增强作用比较明显,在实际的人工林栽培中,可考虑以千年桐和毛竹4:1的比例进行毛阔混交林的营造,以最大程度地增强土壤肥力,提高土壤质量,促进两种树种的共同生长.图2表2参37

Effects of Decomposition of Aleurites montana and Phyllostachys pubescences Mixed Foliage Litter on Activity of Soil Enzymes

One year experiment were conducted on decomposition of Aleurites montana and Phyllostachys pubescences mixed foliage litter samples in a 16-year old A.montana plantation.The litter samples included: A as 100% A.montana foliage,B as 100% P.pubescences foliage,C as mixture of 50% A.montana and 50% P.pubescences foliages,D as mixture of 75% A.montana and 25% P.pubescences foliages and E as mixture of 80% A.montana and 20% P.pubescences foliages.The effects of the mixed foliage litter decomposition on the activity of soil enzymes and the release of organic C,N,P,K,Ca,Mg,Na,Mn and Zn were studied.The results indicated that after one year’s decomposition,the release of N,P,K,organic C,Na,Ca,Mn,Mg and Zn from the foliage litter samples varied significantly.In the 5～10 cm soil layer,the activity of invertase and catalase were higher than those at the other soil layers,with the invertase activity order of E > C > A > CK > D > B and the catalase activity order of E > CK > B > D > A > C.The litter sample E was proved to have positive effects on activity of soil invertase and catalse.Therefore,in silviculture practice,the mixed plantation of 80% A.montana and 20% P.pubescences could be recommended to optimize the soil quality and fertility and facilitate growth of the both species.Fig 2,Tab 2,Ref 37