LITTER FALL, NUTRIENT RETURN AND SOIL FERTILITY UNDER ALBIZIA CHINENSIS : AN AGROFORESTRY TREE SPECIES

摘要

Litter-fall is also associated with the transfer of energy and nutrients to the soil and hence, becomes the initiator of nutrient recycling. Litter on the soil surface therefore, acts as an input system, invariably receiving inputs from the vegetationand in turn releasing nutrients to the soil until litter fall almost equals its decomposition. The study has been conducted in district Hamirpur of Himachal Pradesh to observe the litter-fall pattern, nutrient returned through litter-fall and soil analysis to estimate the soil physico-chemical properties under Albizia chinensis. Non-leaf litter in these species accounted for 56 per cent to the total litter. Out of this miscellaneous litter contributed 26.45 per cent followed by twigs 17.95 per cent, reproductive part 10.43 per cent while the least 1.23 per cent was the contributed by the bark towards total non-leaf litter in A. chinensis. A. chinensis, the highest litter-fall 50.50 and 65.77 g/m~2 was recorded in the month of December and January, respectively thereby together contributed 36.91 per cent of total litter-fall in both the months. In general, total return of nutrients was in the order of Ca > N > K > Mg > P in A. chinensis. The order of nutrient input from different components of litter was leaves > twigs > miscellaneous litter > reproductive litter > bark. In A. chinensis the average annual litter-fall production of was 314.98 g/m~2/yr. The annual litter fall was maximum for leaf followed by miscellaneous, twig and reproductive litter and the least was from bark component. The total nutrient return was 13.27 g/m~2/yr in A. chinensis and out of this calcium contribution was maximum (6.37 g/m~2/yr) followed by nitrogen (3.42), potassium (1.73), magnesium (1.34) and the least was of phosphorus (0.41 g/m~2/yr). Soils under A. chinensis were well enriched in organic matter. Top layer has maximum organic matter (2.59 %) and decreased down with increasing soil depth. In general soils under A. chinensis of the study area were fertile having good physical and chemical health.