Temporal Evolution of Carbon Storage in Chinese Tea Plantations from 1950 to 2010

Tea (Camellia sinensis), an economically important crop grown in mountain regions, has been planted for thousands of years in South China. Tea plantations can potentially act as carbon (C) sink in local agrosystems due to their high plant biomass and provide soil conservation service. To assess the contribution of tea plantations to C sequestration, the chronosequence variations of C storage were assessed in the plants and soils (0–20 cm) of tea plantations in China from 1950 to 2010, and then the inter–annual and decadal variabilities of total C storage were estimated. Total C stocks in tea plants and soils in 2010 were 34.4 and 93.45 Tg, respectively. Carbon sequestration from 1950 to 2010 was 30.6 and 39.0 Tg in the plants and soils, respectively. The highest C sequestration happened during the 1980s and the lowest during the 1950s. The decadal average C sequestration rate ranged from 20.4 to 113.9 g m−2 year−1 in the standing tea plants, and from 54.6 to 98.8 g m−2 year−1 in soils during the period of 1950 to 2010. The average ratio of C storage in soils to that in plants was 3.00 ± 0.35 before 1970 and 2.44 ± 0.18 after 1970. The results suggested that tea plantation ecosystems made an important contribution to the C sinks in Chinese tea–producing regions.