Nutrient Harvest through Pruned Material and whole Tree in <I>Populus deltoides</I> Based Agrisilviculture Systems in Central Punjab

Abstract

The study was carried out at farmers fields to quantify nutrient harvest through biomass of pruned material of 2, 3, 4, 5 and 6 year old plantations and whole tree of Populus deltoides Bartr. (Poplar). The pruned biomass was 327.4, 426.96, 986.27, 1,234.91 and 1,558.59 kg ha^-1 at 2, 3, 4, 5 and 6 year old plantations respectively. The total biomass of branches, main stem and root of poplar at exploitable age was 48,96, 89,144, 94,040 and 12,280 kg/ha, respectively. Nutrient concentration was increased from basal segment to terminal segment of pruned braches and decreased with size of the branches. The nutrient harvest through pruned biomass was 46.32 kg ha^-1 N, 6.92 kg ha^-1 P and 19.93 kg ha^-1 K whereas nutrient loss through whole tree was 652.8 kg ha^-1, 75.84 kg ha^-1 P and 719.84 kg ha^-1 K. As the nutrient is exceeded than annual return, additional doses of fertilizers may be required to maintain soil fertility and productivity of the system.