Bioproductivity and nutrient cycling in bamboo and acacia plantation forests.

This study mainly aimed to investigate the bioproductivity and nutrient cycling processes in plantation forests of bamboo and acacia. In India, multipurpose tree (MPT) species are extensively planted to meet the increasing demand for fuel and industrial wood. The bioproductivity studies of bamboo showed that the total biomass increased with age (2.2 t/ha/year 1) up to six years (297.8 t/ha/year 6) and then decreased (15.6 t/ha/year 10). With acacia, the total biomass increased from 1.8 t/ha/(year 1) to 5.0 t/ha/ (year 3) and 10.9 t/ha/(year 5). In general the biomass increased with increase of diameter and height. Nutrient cycling in the plantation on an annual basis was worked out. A complete harvest of bamboo in 6 years removes 2341 kg/ha of nitrogen, 22 kg/ha of phosphorus, 2,653 kg/ha, of potassium, 1,211 kg/ha of calcium and 1,356 kg/ha of magnesium. A total harvest of above ground biomass of acacia in 3 years removes (kg/ha) 91.74 N, 2.53 P, 73.41 K, 110.45 Ca, 14.06 Mg, and in 4 years removes (kg/ha) 227.47 N, 7.34 P, 181.04 K, 284.15 Ca, and 38.89 Mg.