鼎湖山南亚热带森林群落演替对土壤化学性质影响的累积效应研究

Accumulative Effects of Forest Community Succession on Soil Chemical Properties in Dinghushan of Tropical China

比较研究了南亚热带鼎湖山森林群落演替序列中马尾松林、针阔混交林和季风常绿阔叶林表层(0～20cm)土壤pH值、有机质、全N、速效K、交换性Ca和Mg、有效P、B、Mo、Cu、Fe、Zn和易还原Mn等营养元素的含量及其相关关系,结果表明:马尾松林土壤pH值显著高于其它两森林土壤;随着群落的进展演替,养分在土壤中的累积(Ca除外)呈不断增加的趋势,即马尾松林<针阔叶混交林<季风常绿阔叶林;不同指标的累积呈现出持续增加(有机质、交换性Mg、有效B、Mo、Cu、Fe和易还原Mn)、持续递减(交换性Ca)、先增加再减少(有效P)和先减少再增加(pH值、总N和有效Zn)的4种变化形式;土壤养分元素的相关对对数以马尾松林最多。植物对土壤性质的影响累积效应显著,森林群落的进展演替过程是土壤养分不断积累的过程,土壤有效养分元素来源也趋多元化。

Comparative studies on the pH value, organic matter, total N, exchangeable Ca and Mg, available K, P, B, Mo, Cu, Fe, Zn, Mn in the 0~20 cm soil layer among the 3 forests, Pinus massoniana forest(PMF), pine and broadleaf mixed forest(PBMF), and monsoon evergreen broadleaf forest(MEBF) which consists of a succession series in Dinghushan, south China show that the pH value in PMF soil(4.34±0.09) was distinctly higher than that in PBMF(4.15±0.11) and MEBF(4.19±0.10); As progressive succession proceeded, the organic matter, exchangeable Mg, available B, Mo, Cu, Fe, and Mn in soil were ranked in the order PMF<PBMF<MEBF, but the exchangeable Ca was PMF (2.15±0.35) mmol (Ca^(2+))/kg)>PBMF(1.79±0.32 mmol(Ca^(2+))/kg)>MEBF (1.42±0.33 mmol(Ca^(2+))/kg). Meanwhile the available P in soil was increasing from PMF(1.96±0.67) g/kg to PBMF(2.60±0.72) g/kg dominantly then decreasing from PBMF to MEBF(2.38±0.87) g/kg, but total N and available Zn were decreasing from PMF to PBMF then increasing from PBMF to MEBF. Their correlation element-couples in the soil under PMF were more than that under others. Plant community could exert an dominantly influence on soil nutrient reserve. With plant community succession progressing, soil nutrients content keep on accumulating and soil nutrient come from multi-source.