How different reforestation approaches affect red soil properties in southern China

Significant differences were found in soil physicochemical and biological effects between various forest restoration approaches of a hilly red-soil region, southern China. Soil quality was the highest in natural secondary forest (0.95), while in sites revegetated with tea-oil camellia (Camellia oleifera), Chinese fir (Cunninghamia lanceolata) and slash pine (Pinus elliottii) and control sites, integrated soil quality indices were 0.68, 0.55, 0.36 and 0.04 respectively. The lower soil quality of plantations and controls resulted from increased disruption of soil physical structure, lower quality litter fall, lower litter fall production, reduction in microbial biomass, decline of microbial function and loss of soil nutrients due to periodically artificial tending and accelerated soil erosion. Improvement in soil physicochemical properties and enhanced soil microbial function at a natural secondary forest site demonstrated the inherent restoration of these soils. Hence, natural restoration, as well as reducing human disturbance, is a better approach to improving soil properties than returning farmland to planted woodlands. Copyright (c) 2005 John Wiley & Sons, Ltd.