南亚热带不同植被恢复模式下土壤理化性质

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

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.

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 physi-cal 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 of soil 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.