Diameter class wise apportioned growth and productivity of Melia dubia Cav. under silvi-horticulture system -A case study from south Gujarat

Abstract

The present investigation entitled was carried out in the year 2022, at Karadi Village, Navsari (Gujarat), situated at situated at 20.923˚N latitude,72.850˚E longitude and at an altitude of 9 m above mean sea level, near Arabian sea.   The average height ranged from 11.03 to 16.02 m in DBH class 6.50-9.00 to 24.00-26.50 cm, respectively. Form quotient also varied with DBH class and it ranged from 0.56 to 0.64 in 21.50-24.00 and 9.00-11.50 cm DBH class, respectively.  The mean tree volume varied from 0.038 to 0.410 m3 from 6.50-9.00 to 24.00-26.50 cm DBH class, respectively and it showed increasing trend as DBH increased. Whereas, tree volume (m³/tree) and fresh biomass (kg/tree) estimated using regression equation, indicated that the average DBH class wise volume ranged from 0.027 to 0.281 m3/tree under lowest (6.50-9.00 cm) and highest DBH class (24.00-26.50), respectively, whereas, the average fresh biomass varied between 30.87 to 283.47 kg/tree in 6.50-9.00 cm to 24.00-26.50 cm DBH class. At 5 years of age, DBH class wise productivity of volume (m³/ha/year) and biomass (tonne/ha/year) ranged from 4.32 to 44.96 m³/ha/year 4.94 to 45.36 tonne/ha/year under 6.50-9.00 cm and 24.00-26.50 cm DBH class, respectively with overall mean productivity of 22.69 tonne/ha/year. The DBH class wise economic returns on account M. dubia of fresh biomass indicated that Rs. 0.98 lakh/ha could be accrued from DBH class ranging from 6.50-9.00 cm and it could be maximum to the tune of Rs. 1.11 lakhs/ha from the trees having DBH range of 24.00-26.50 cm with overall returns of 5.42 lakhs/ha.