关键词: 华北落叶松, 白桦, 叶凋落物, 室内分解, 土壤养分

Abstract:

Mesh nylonbag method was used to set up indoor mixed litter decomposition tests of Larixprincipis-rupprechtii and Betula platyphylla.Five mixture proportions treatments were set up:pure Larixprincipis-rupprechtii litter,pure Betula platyphylla litter,50% Larixprincipis-rupprechtii litter mixed with 50% Betula platyphylla,66.7% Larixprincipis-rupprechtii litter mixed with 33.3% Betula platyphylla,and 75% Larixprincipis-rupprechtii litter mixed with 25%Betula platyphylla.The results showed that:the litter decomposition rate of Betula platyphylla was significantly higher than that of pure Larixprincipis-rupprechtii,the admixture of Betula platyphylla leaf litter could promote Larixprincipis-rupprechtii litter decomposition,the effect was more obvious as the proportion of Betula platyphylla leaf litter increased;during the whole decomposition process,N and P contents in leaf litter showed an increase tendency,while K,C contentsand C/N ratio presented an opposite tendency;the pure Betula platyphyllalitter release rates of N,K and C were greater than that of pure Larixprincipis-rupprechtii,the admixture of Betula platyphylla leaf litter could promote Larixprincipis-rupprechtii litter release of N,K and C,while the release rate of P was inhibited;leaf litter decomposition can improve soil pH and nutrient content.Soil pH,organic matter,available N,P,K were increased.Overall,mixed litter decomposition of Larixprincipis-rupprechtii and Betula platyphylla can improve the soil nutrient better than the single litter decomposition of Larixprincipis-rupprechtii.

Key words: Larixprincipis-rupprechtii, Betula platyphylla, leaf litter, indoor decomposition, soi lnutrient