Structure and Function of an Age Series of Eucalypt Plantations in Central Himalaya. I. Dry Matter Dynamics

Abstract

The biomass and net primary productivity (NPP) of 2- to 8-year-old plantations of Eucalyptus tereticornis Sm. (= E. hybrid) growing in the tarai (a level area of superabundant water) region of Central Himalaya were estimated. Allometric equations for all the above-ground and below-ground components of trees and shrubs were developed for each stand. Understorey, forest floor biomass and litter fall were also estimated from stands. Shrubs appeared first at 5-year-old plantation. The biomass of vegetation, forest floor littermass, tree litter fall and net primary productivity (NPP) of trees and shrubs increased with the increase in plantation age, whereas herb biomass and NPP significantly (P < 0·01) decreased with the increase in plantation age. The total plantation biomass increased from 7·7 t ha⁻¹ in the 2-year-old to 126·7 t ha⁻¹ in the 8-year-old plantation and NPP from 8·6 t ha⁻¹ year⁻¹ in the 2-year-old to 23·4 t ha⁻¹ year⁻¹ in the 8-year-old plantation. The biomass accumulation ratio ranged from 0·81 to 5·93.