南亚热带不同植被恢复模式下土壤理化性质

分析了广西大青山南亚热带11种植被恢复模式下（1种天然次生林、2种人工针叶林、5种人工常绿阔叶林、2种人工针阔混交林和1种灌丛）土壤理化性质的变化特征.结果表明:不同植被恢复模式下土壤理化性质存在明显差异.其中，次生林林地土壤的物理性质良好，2种针叶林较差.2种针阔混交林土壤容重较小，土壤总孔隙度、土壤持水量均高于其他人工纯林；而5种人工常绿阔叶林的土壤孔隙度差异不明显.次生林土壤除全K低于柚木林外，其余养分含量均明显高于人工林，C/N和pH值相对较低.与荒草灌丛相比，9种人工林的土壤养分变化明显，全N和速效P含量均呈增加趋势；2种针叶纯林的土壤养分含量较低，但与红椎混交后，土壤养分含量明显改善，C/N值降低.

Soil physical and chemical characteristics under different vegetation restoration patterns in China south subtropical area

This paper studied the change of soil physical and chemical properties under eleven vegetation restoration patterns (1 kind of secondary forest, 2 kinds of pure coniferous plantations, 5 kinds of evergreen broad-leaved plantations, 2 kinds of conifer and broad-leaved mixed plantations, and 1 kind of shrub) typical in Daqingshan of Guangxi. Obvious differences were observed in the soil physical and chemical properties under different vegetation restoration patterns. The soil physical properties were better in secondary forest but poorer in pure conifer plantations. Conifer and broad-leaved mixed plantations had lower soil bulk density, and their soil total porosity and water-holding capacity were higher than those in pure plantations. There were no significant differences in the soil porosity among the 5 evergreen broad-leaved plantations. Except that of soil total K, the contents of soil nutrients in secondary forest were higher than those in plantations, and the soil C/N ratio and pH value were relatively lower. Comparing with shrub, the 9 plantations had an obvious change in their soil nutrient contents, e.g., the increase ofsoil total N and available K. The 2 pure coniferous plantations had lower soil nutrient contents, but after mixed planted with evergreen broad-leaved trees, their soil nutrient contents increased markedly, and the soil C/N ratio decreased.