Storage and flux of nutrients in a dry tropical forest in India

Abstract

Storage and flux of N, P, Ca, K and Na were studied in a dry tropical forest The nutrient concentrations in different growth forms were in the order herb > shrub > tree, whereas the standing state of nutrients followed the order tree > shrub > herb The total storage (kg ha⁻¹) in vegetation amounted to 567 N, 37 P, 278 Ca, 256 K and 46 Na The share of above-ground parts in vegetation storage was 82 % for N, 83 % for P, 76 % for Ca, 85 % for K and 79 % for Na From 56 to 71 % of foliar N, P and K was withdrawn during senescence Nutrient input (kg ha⁻¹ year⁻¹) from the vegetation (above-ground + below_ground) to forest floor amounted to 115 N, 8 P, 62 Ca, 38 K and 10 Na compared to total net annual uptake (kg ha⁻¹) of 143 N, 10 P, 78 Ca, 52 K and 12 Na, indicating marginal accumulation in the system Fine roots were as important a pathway of nutrient return as leaf litter Turnover rate and turnover time for different nutrients on the forest floor ranged, respectively, between 72 and 83 % and 12 and 1 39 years.