Biomass production and soil amelioration in a high density Terminalia arjuna plantation on sodic soils

Three plant densities of Terminalia arjuna (10 000, 20 000 and 30 000 plants ha−1) established on a sodic wasteland, were evaluated for their biomass production potential, energy content and soil amelioration at Lucknow, India (80°53′ E; 26°45′ N). Height, diameter and biomass production increased significantly (P<0.05) from lower to higher plant density. The yearly growth and biomass accumulation also increased significantly upto six years. The highest density plantation accumulated 516 GJ ha−1 energy content at six years. The impact of the plant density on soil properties showed a significant reduction in soil bulk density, whereas the porosity and water holding capacity of the soil increased at the highest density. Soil pH, exchangeable sodium percentage and exchangeable Na+ were reduced with the plant age and plant density whereas organic C, K+, Ca++ and Mg++ cations increased with plant growth as well as plant density