Estimation of above-ground biomass and carbon stock of an invasive woody shrub in the subtropical deciduous forests of Doon Valley, western Himalaya, India

This study describes the different parameters used to derive the allometric equation for calculating the biomass of an invasive woody shrub Lantana camara L. from the subtropical conditions of western Himalaya. It identifies the most accurate and convenient method for biomass calculation by comparing destructive with non-destructive methodology. Different parameters were measured on a wide range of Lantana from different community levels for the non-destructive calculation of total above-ground biomass. Different explanatory variables were identified and measured such as basal diameter either as a single independent variable or in combination with plant height. The other suitable combinations of available independent variables include crown length, crown width, crown area, crown volume and coverage of the plant. Amongst the wide range of allometric equations used with different variables, the equation with D²H as a variable was found to be the most suitable estimator of biomass calculation for Lantana. Sahastradhara, being the most disturbed area due to its high tourist activity round the year, showed maximum coverage (58.57 % ha⁻¹), highest biomass (13,559.60 kg ha⁻¹) and carbon density (6,373.01 kg ha⁻¹) of Lantana. The degree of Lantana’s invasiveness in subtropical conditions was also calculated on the basis of importance value index (IVI). The maximum IVI (22.77) and mean coverage (26.8 % ha⁻¹) was obtained from the areas near Jolly Grant airport, indicating that physically disturbed areas are more suitable for the growth of Lantana, which may significantly increase shrub biomass. The importance of incorporating allometric equations in calculation of shrub biomass, and its role in atmospheric carbon assimilation has thus been highlighted through the findings of this study.