Deposition and decomposition of litterfall of Pinus cooperi C.E.Blanco in El Salto, Durango, México

Abstract

The objective of the present work was to determine the deposition and decomposition rate of Pinus cooperi litterfall in plots subjected to different thinning intensities (treatments) (Control; T1:light thinning; T2: moderate; T3: intense; T4: very intense; T5: final crop tree thinning) at ejido La Ciudad in Pueblo Nuevo, Durango. After one year of observation, the maximum accumulation of litter was registered in the control treatment (4.90Mg·ha^-1·year^-1), followed by T2 (3.76Mg·ha^-1·year^-1), T1 (3.65Mg·ha^-1·year^-1), T4 (3.25Mg·ha^-1·year^-1), and T3 (3.04Mg·ha^-1·year^-1), while T5 had the lowest annual litterfall (2.58Mg·ha^-1·año^-1). The litterfall decomposition rate (k) was determined according to the Olson exponential model. Decomposition rates were higher during the first 150 days of incubation than during the subsequent 210 days. In both periods, there were significant differences between treatments. After 360 days of incubation, the greatest litterfall decomposition occurred in T3 (42.3 %) regardless of the forest conditions. In the rest of treatments, the decomposition varied from 30.2 (T1) to 37.1 % (T5). Although T3 was significantly faster than the other treatments under the microclimate conditions offered by the studied types of thinnings, no differences were detected between the decomposition rates with the five treatments evaluated in this study.