Effects of intensive and extensive management on soil active organic carbon in bamboo forests of China

Abstract

Aims Our objective was to determine the effects of intensive cultivation on soil organic carbon(SOC) in bam-boo(Phyllostachys heterocycla 'Pubescens') forests.Methods We used the reference land unit method and collected soil samples in intensively and extensively managed bamboo forests in the spring.Important findings Under intensive management,total organic carbon(TOC) decreased by 7.01% and 18.90% and readily oxidized carbon(ROC) decreased by 31.22% and 46.03% in 0-10 and 10-20 cm soil layers,respec-tively.Also,light fraction organic matter(LFOM) decreased 19.87% in the 0-20 cm soil layer.Soil organic car-bon under the two types of management decreased with increasing soil depth,but the ranges of decrease were dif-ferent.The vertical distribution of ROC under extensive management paralleled that of TOC,while both were different under intensive management.LFOM tended to accumulate in surface layers(0-20 cm).TOC,ROC and LFOM were strongly correlated with soil nutrients(p 0.01),and TOC was significantly related to available P(p 0.05).After intensive management,the percentage of ROC to TOC and activity of carbon pool significantly dropped by 26.01% and 50.52%(p 0.05),respectively,in the 0-10 cm soil layer and dropped by 35.51% and 54.41% respectively in the 10-20 cm soil layer.Therefore,a mixture of organic and inorganic manures with the proper ratio should be applied to promote SOC and improve biological and chemical soil activity.