Carbon storage and sequestration rate assessment and allometric model development in young teak plantations of tropical moist deciduous forest, India

Abstract

Carbon (C) sequestration through plantations is one of the important mitigation measures for rising levels of carbon dioxide and other greenhouse gases in the atmosphere. This study aimed to assess C stocks and their sequestration rate, and to develop allometric models for estimation of C stocking in age-series young teak (Tectona grandis) plantations (1, 5, 11, 18, 24 and 30 years) by using biomass and productivity estimation and regression, respectively. These plantations were raised in tropical moist deciduous forests of Kumaun Himalayan tarai. Total C stocks estimated for these plantations were 1.6, 15.8, 35.4, 39.0, 61.5 and 73.2 Mg ha⁻¹, respectively. Aboveground and belowground C storage increased with increasing plantation age; however, the range of their percentage contribution showed little variation (87.8–88.2 and 11.7–12.7 %, respectively). The rate of C sequestration for these respective plantations was 1.06, 6.95, 5.46, 5.42, 3.39 and 5.37 Mg ha⁻¹ a⁻¹. Forty percent of the aboveground annual storage was retained in the tree while 60 % was released in the form of foliage, twigs, and fruit litter. In the case of total (tree) annual production, 43 % was retained while 57 % was released as litter including root. C stock, C sequestration rate, accumulation ratio (1.4–18.1), root:shoot C ratio (0.61–0.13) and production efficiency (0.01–0.18) were comparable to some previous reports for other species and forests. These data could be useful in deciding the harvesting age for young teak with respect to C storage and sequestration rate. Four allometric models using linear regression equations were developed between biomass (twice the C stock) and diameter, girth, and height of the tree at different ages. The diameter model was found more suitable for C stock prediction in similar areas.

Keywords

Age series / Biomass / Carbon budget / DBH / Productivity / Production ratios / Regression equations / Tectona grandis

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