Biomass Production in Energy Plantations of <I>Prosopis juliflora</I>

Abstract

Studies on time trends of biomass production by means of age series in energy plantations (spacing 1.3 × 1.3 m) of Prosopis juliflora is presented. The component wise biomass production at the age of 18, 24, 30, 36 and 48 months was determined. The results show considerable variation among the population of trees. However, distinct linear relationship between girth at breast heighht (GBH) and total height was discernible. The total biomass produced at 18, 24,30,36 and 48 months of age was 19.69, 41.39, 69.11, 114.62 and 148.63 dry tonnes per hectare, respectively, the corresponding figures for utilizable biomass wood, bark and branch) were 14.63, 32.17, 50.59, 88.87 and 113.25 dry tonnes per hectare. At all the periods of study, branch component formed the major portion of total biomass being around 50 to 55 per cent utilizable biomass was three fourth of total biomass at all ages. The solar energy conversion efficiency ranged from 0.59 per cent at 18 months to 1.68 per cent at 48 months of age the peak value being 1.87 per cent at the age of 36 months. It is shown that the variable diameter and height can be used to reliably predict the biomass production in Prosopis juliflora with the help of the regression equations developed in the present study. It is cuncluded that Prosopis juliflora is an ideal candidate for energy plantations in semi arid and marginal lands, not only to meet the fuelwuod demands but also to improve the soil fertility, for, this plant is fast growing and nitrogen fixing leguminous tree.