Leaf litter production and decomposition dynamics in four agroforestry tree species of western Himalayas
Litter fall and its subsequent decomposition in the soil are two essential ecosystem processes. In order to determine the soil fertility improvement potential of a tree species, it is necessary to evaluate litter production, its temporal variation, and rates of decomposition and nutrient cycling. In this study, we examined patterns of litter fall production and decomposition four agroforestry tree species (Celtis australis, Grewia optiva, Bauhinia variegata and Ficus roxburghii) from western Himalayas, India. Average litter fall was 2190 kg/year/ha and varied significantly among species. Leaf litter production in a year was maximum in case of Grewia optiva statistically at par with C. australis whereas F. roxburghii recorded minimum amount of annual leaf litter. In a litterbag experiment, all species had fast mass loss in the first six months of decomposition, coinciding with the rainy season. Celtis australis had significantly higher decomposition rate than all other species whereas F roxburghii exhibited slowest rate of decomposition. We recommended C. australis and G. optiva for soil fertility improvement because of their fast growing characteristic, high litter production and rapid decomposition. However where the objective is to use the leaf litter as mulch for protection against soil and water erosion as well as moisture retention, F. roxburghii will be more suitable because leaf biomass will be remained as mulch for longer period.