STATISTICAL MODELS FOR PREDICTION OF GROWTH AND YIELD OF DALBERGIA SISSOO AND HARDWICKIA BINNATA UNDER SILVIPASTORAL SYSTEM IN INDIA

摘要

A field experiment was initiated at National Research Centre for Agroforestry (NRCAF), Jhansi, India to study the effect of pruning treatment on the growth and yield of Dalbergia sissoo and Hardwickia binnata under silvipastoral system. The experimentconsisted of two treatments viz naturally grown trees and pruned trees (50%) planted at a spacing of 6 x 4m. At the age of ten years, eight trees were harvested from both the tree species and under each of two treatment for above ground biomass components and volume estimates. The mean above ground dry biomass (AGB) production under pruned and unpruned conditions was 68.43, 128.36 kg/tree for D. sissoo and 28.17, 61.24kg/tree for H. binnata respectively. Allometric functions were used to develop modelfor estimation of AGB on the basis of dbh (diameter at breast height) and the fitted equations were AGB=0.666*(dbh)1831 for Dalbergia -unprunned; AGB=0.61 l*(dbh)1.752 for Dalbergia -prunned and AGB=5.973*(dbh)°917 for Hardwickia -unprunned; AGB=2.246*(dbh)' 086 for Hardwickia -prunned respectively. The above ground biomass productivity (tons/ha/yr) ranged from 2.73 to 5.13 for D. sissoo in case of pruned and unpruned respectively, whereas the wood volume index (m~3/ha/yr) ranged from 2.8 to 4.4 respectively. In case of H. binnata, the biomass productivity was observed from 1.10 to 2.44 and wood volume index from 1.12 to 2.24 respectively under pruned and unprunned conditions.