DRY-MATTER AND NUTRIENT DYNAMIC OF LITTER DURING FOREST REGROWTH IN HUMID SUBTROPICS

Seasonal variation in dry matter and nutrient accumulation patterns in litter during regrowth of three subtropical humid forest stands (7-, 13- and 16-yrs after tree cutting) were studied. The litter mass was m aximum during winter and minimum during autumn in all the three forest regrowths. Mean annual litter accumulation was highest in 13-yr old r egrowth (2120.8 kg.ha(-1)), followed by 16-yr (1856.1 kg.ha(-1))and 7- yr (1389.9 kg.ha(-1)) old regrowths. Leaf litter constituted 38-74 % o f the total litter accumulated in these regrowths. Generally, the conc entration of nutrients such as N, P, K and Ca in the litter did not va ry significantly through seasons. However, the leaf litter had higher concentrations of N, P and K than the woody and miscellaneous fraction s, whereas, the Ca concentration was larger in the woody litter. The n utrient content of the litter varied seasonally like that of the dry m ass. In all the three forest regrowths, N accumulation in the litter w as highest and P accumulation was the lowest, while, K and/or Ca were an intermediate of these two extremes.