重庆紫色土区不同森林恢复类型对土壤质量的影响

为了探讨不同森林恢复类型对土壤质量的影响,对南方紫色土区4种主要森林恢复类型及对照地土壤物理和化学特性进行了比较研究。结果表明：4种森林类型的土壤质量均高于长期干扰下对照的土地,天然次生林土壤质量又高于人工林,5种不同状况下土壤质量综合指数由大到小为：天然次生林（0.97）、石栎（Lithocarpus glaber）×木荷（Schima superba）阔叶混交林（0.77）、枫香（Liquidambar formsana）×木荷×石栎×香樟（Cinnamomum camphora）阔叶混交林（0.67）、杉木纯林（0.41）、对照（0.04）。导致人工林和对照地土壤质量相对较低的主要原因是：周期性的森林抚育使土壤结构较差、凋落物量较低和土壤养分流失严重。研究表明,在植被恢复初期阶段,自然恢复是最大限度发挥森林功能的有效途径。

Effects of different forest restorations on soil quality in purple soil area, Chongqing

To analyze the effects of different forest restorations on soil quality,the soil physical and chemical properties under four main forest restoration types and the control areas were compared.The results showed the soil quality of four forest restoration types was higher than that of control areas,and the soil quality of natural secondary forest was higher than that of plantations.The comprehensive indices for soil quality of five restorations were： natural secondary forest（0.97）,Lithocarpus glaber×Schima superba×Cinnamomum camphora×Liquidambar formsan（0.67）,Lithocarpus glaber×Schima superba（0.77）,Cunninghamia lanceolat（0.41）,control areas（0.04）.The reason that plantations and control areas have worse soil quality than natural secondary forest is that periodic management had broken soil structure,less leaf litter fall,and severe nutrients loss.This research shows that in the beginning stage of forest restoration,natural restoration is an effective way to improve soil quality.