Biomass and net primary productivity in Leucaena, Acacia and Eucalyptus, short rotation, high density (‘energy’) plantations in arid India

The present study estimates above-ground biomass and net primary productivity in high density (‘energy’) plantations of three important species raised at Hisar (29 °10′N, 75 °46′E, 215 m.a.s.l.) in arid India. In 4-year-old plantations, with initial plant spacing of 0•6 × 0•6 m (which is generally used for production of fuelwood), Leucaena leucocephala showed fairly high net primary productivity (33 t ha−1 year−1) closely followed by Eucalyptus tereticornis (29 t ha−1 year−1). In both species, the values were about two-fold higher than Acacia nilotica. Of the total net primary productivity, 23 to 27% returned to the soil as litterfall. The standing biomass after 4 years was 112 t ha−1 in L. leucocephala, 96 t ha−1 in E.tereticomis and 52 t ha−1 in A.nilotica. In 8-year-old plantations with initial spacing of 2 × 2 m (which is generally used for small timber and fuelwood), the net primary productivity was 25 t ha−1 year−1 in L. leucocephala, 21 t ha−1 year−1 in E.tereticomis and 14 t ha−1 year−1 in A. nilotica; and 38 to 45% of it was returned to the soil as litterfall. After 8 years of growth, biomass was 126 t ha−1 in L. leucocephala, 102 t ha−1 in E. tereticomis and 77 t ha−1 in A.nilotica. The plantations have a high potential for the production of biomass.