Litter dynamics of recently harvested and mature bamboo savannas in a dry tropical region in India

Abstract

ABSTRACTAnalysis of litterfall, nutrient return and floor mass dynamics was made in mature and recently harvested bamboo savanna sites in a dry tropical region in India. The total annual litterfall was 590 and 267 g m–2 in mature and harvested sites, respectively. Of the total litterfall, 58–77% by weight was contributed by leaf litter. Although litterfall occurred throughout the year, as much as 72–83% of the leaf litterfall was recorded during winter (December–February). Seasonal distribution of total litterfall was: rainy 12–22% of annual, winter 64–65% and summer 13–22%. Nutrient concentrations in bamboo leaf litter were low compared with the other species growing in the same region. Annual nutrient return through litterfall amounted to: 28–49 kg N ha–1, 1.32.9 kg P ha–1, 33–85 kg Ca ha–1, 12–32 kg K ha–1 and 1.4–2.8 kg Na ha–1. While maximum accumulations of fresh litter on the ground occurred in summer, the partly decayed and particulate litter categories peaked in the rainy season. Decaying litter categories showed 1.5–3 times greater nutrient concentrations than the concentrations in fresh leaf litter. Marked immobilization of N and P occurred in decomposing leaf and particulate litter. The mean annual nutrient content of the floor was (kg ha–1): N 29–40, P 1.0–1.9, Ca 13.8–23.9, K 14.6–15.3 and Na 0.85–0.99. The annual turnover in litter layer was: 63–81% for dry mass and 64–90% for different nutrients.