Biomass Carbon Stock of Tea Plants in Mature Tea Fields

Abstract

Carbon stocks in the biomass of 28- or 29- and 40-year-old tea plants were investigated by measuring the dry biomass and total carbon content of each part of the tea plants (Camellia sinensis L. var. ‘Yabukita’), which have grown under the standard management in Shizuoka Prefectural Research Institute of Agriculture and Forestry, Tea Research Center. A linear regression analysis of the carbon stock in the tea leaves and branches above the standard pruning surface, which was assumed to be 50 cm above the ground of tea fields, provided a prediction of the carbon stock above the pruning surface as a function of the distance between the canopy and pruning surfaces. Based on the regression equation, the carbon stock in the upper aboveground part above the standard pruning surface of 30-year-old tea plants of the average plant height was estimated to be 4.81 t-C ha^-1. The carbon stocks in the lower aboveground part under the standard pruning surface and belowground part were estimated to be 14.0 and 12.5 t-C ha^-1, respectively. The total carbon stock of 30-year-old tea plants of the average plant height, i.e., the sum of above- and belowground parts, was estimated to be 31.3 t-C ha^-1. The carbon stock in the aboveground biomass under the pruning surface of 40-year-old tea plants was almost same as that of 28- or 29-year-old tea plants. The carbon stock in the belowground biomass of 40-year-old tea plants was significantly larger than that of 28- or 29-year-old tea plants.