Effects of detritus removal on soil carbon, nitrogen and phosphorus stoichiometry and related factors in a temperate deciduous forest in the Maoershan Mountain, China.

Abstract

A detritus-removal experiment was conducted in a temperate deciduous broad-leaved forest in 2007 at the Maoershan Ecological Station in Northeast China, including two treatments: Litterfall removal (NL), root removal (NR). Soil water content, bulk density and the concentrations of soil C, N and P were measured in 2016. The results showed that the C concentration at the surface soil layer (0-10 cm) was reduced by 15.6% and 10.7% for the NL and NR treatments, respectively, while the weighted-mean soil C concentration in 0-30 cm depth was reduced by 7.9% and 4.6%, respectively. The N concentration of the surface layer in the NL treatment decreased by 10.2%, whereas the surface-soil P concentration in the NR treatment increased by 6.6%, resulting in reduced C:P and N:P for both treatments. The standardized major axis regressions showed that the regression slopes between the C, N and P at each layer of 0-30 cm soil depth differed significantly among the treatments. The intercepts of the regressions between soil C concentration and bulk density or soil water content had significant differences among the treatments. The results suggested that detritus-removal caused a coordinated variation in soil C, N and P stoichiometry and physical properties. Therefore, we recommend taking the effect on soil ecological stoichiometry into account in future detritus-removal experiments.