Characteristics of soil organic carbon components in a secondary Castanopsis platyacantha- Schima sinensis evergreen broad-leaved forest, Wawushan Mountain

Abstract

Secondary forests are one of the most important fast鄄growth forest types, with a large distribution area and high potential carbon sequestration capacity. In order to investigate the component characteristics of soil organic carbon in a subtropical secondary evergreen broad鄄leaved forest, an experiment was conducted in a typical evergreen broad鄄leaved secondary forest (Castanopsis platyacantha鄄Schima sinensis) in the middle section of Wawushan Mountain, southwest China. The physical soil properties and soil carbon fractions were studied, with the soil profile divided (0-10, 10-40, 40-70 cm and 70-100 cm) and sampled. Results showed that the soil at each level was acidic. Soil potential acidity was between 3.2 and 4.0, field moisture capacity was 63%-190%, and total porosity and bulk density were 63.0%-83.3% and 0.41-0.99 g / cm 3 respectively. Soil pH value and bulk density increased with increased soil depth, while the field moisture capacity and total porosity showed the opposite trend. The organic carbon content of litter was 443 g / kg, and the litter stock and litter carbon stock were 10.4 t / hm 2 and 4.5 t / hm 2 , respectively. Litter organic C stock in the studied forest was higher than in the majority of the plantations and natural forests in Sichuan Province. Soil organic carbon, microbial