Organic carbon sequestration at different age of tea [Camelia sinensis] plantation under the wet tropical area

Abstract

Soil organic carbon [OC] sequestration is affected by some factors, one of which is the vegetation living on it. Tea is a crop on which the part being harvested is the leaves, which are supposed to contribute to soil OC. The objective of the research was to determine the amount of OC sequestered at different crop age under tea plantation in wet tropical areas. The soil samples were taken from 3 different crop ages [36, 21, and 9 years old] under the same slope [>45%] and soil [volcanic] at ≥ 1,400 m asl. As a comparison, the soil was also sampled from the secondary forest around the research site. At each crop age and the forest, the soil was sampled for 100 cm depth with a 20 cm increment. Undisturbed soil samples were taken for soil BD and disturbed soil samples for OC. The result showed that SOC content decreased by soil depth, and the soil BD was not significantly different among the depths. Therefore, the amount of OC sequestered declined by decreasing soil depth. The SOC sequestration rate decreased by increasing the age of tea crop from 1.67 to 0.49 Mg/Ha/y/1-m depth respectively between 9-21 and 21-36 years old. Compared to the secondary forest, however, the OC sequestration under tea plantation improved by 1.50, 1.71, and 1.79 times as the age of tea crop increased from 9, to 21, and to 36 years old, respectively. It seems that tea cultivation is the potential to sequester OC even though the leaves are regularly harvested.

Effect of Land Use Change on Soil Physico-chemical Characteristics in Sungai Batang, east part of Maninjau caldera

“…It could improve or worsen soil behavior. Land-use change from forest to corn cultivation reduced SOM stock by 128% under Inceptisols and 14% under Oxisols in Lima Puluh Kota, the tropical area (Yulnafatmawita et al 2020). However, Yulnafatmawita et al (2020) reported land-use conversion from the forest into tea plantation in volcanic soil in Batang Barus dan Gunung Talang, Solok Regency, increased SOM stock and improved soil physical properties.…”

“…Land-use change from forest to corn cultivation reduced SOM stock by 128% under Inceptisols and 14% under Oxisols in Lima Puluh Kota, the tropical area (Yulnafatmawita et al 2020). However, Yulnafatmawita et al (2020) reported land-use conversion from the forest into tea plantation in volcanic soil in Batang Barus dan Gunung Talang, Solok Regency, increased SOM stock and improved soil physical properties. Landuse change from forest to others in recently developed soil in the east part of Maninjau caldera was studied to determine the effect on soil physicochemical properties.…”

“…High BD and low TSP in most of the land use in Sungai Batang were due to the development of the soil, which was relatively new, proved by high sand and low clay particles. Sandy textured soils (Tabel 1) having a high percentage of macropores are easy to pass water Yulnafatmawita et al (2020). reported that soil under tea plantations with high SOM content had low soil BD and high TSP and permeability rate.…”

Role of coffee plantation in reducing erosion under coarse textured soil in wet tropical region

“…Ref. [10] reported that tea plantation in the Aie Batumbuak, Gunung Talang District was planted on sloping area (>100% slope). However, there were no visible signs of erosion on the ground surface, and no landslide hazard had ever been there.…”

“…Land conversion will change the amount and quality of OM contributed to the soil. Yulnafatmawita et al [10] reported that land-use changes from secondary forest to tea plantations in Gunung Talang District were able to increase the OM content of the soil. Furthermore, Tumwebaze and Byakagaba [13] stated that the coffee agroforestry system could be a method to improve OM accumulation in the terrestrial to minimize global warming.…”