LITTER DYNAMICS OF RECENTLY HARVESTED AND MATURE BAMBOO SAVANNAS IN ADRY TROPICAL REGION IN INDIA

Analysis of litterfall, nutrient return and floor mass dynamics was ma de in mature and recently harvested bamboo savanna sites in a dry trop ical region in India. The total annual litterfall was 590 and 267 g m( -2) in mature and harvested sites, respectively. Of the total litterfa ll, 58-77% by weight was contributed by leaf litter. Although litterfa ll occurred throughout the year, as much as 72-83% of the leaf litterf all was recorded during winter (December-February). Seasonal distribut ion 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 nu trient return through litterfall amounted to: 28-49 kg N ha(-1), 1.3-2 .9 kg P ha(-1), 33-85 kg Ca ha(-1), 1 2-32 kg K ha(-1) and 1.4-2.8 kg Na ha(-1). While maximum accumulations of fresh litter on the ground o ccurred in summer, the partly decayed and particulate litter categorie s 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 a nd Na 0.85-0.99. The annual turnover in litter layer was: 63-81% for d ry mass and 64-90% for different nutrients.