Carbon release from agricultural cultivated peats at Sungai Hitam Wetland, Bengkulu Province, Indonesia

This research aimed to determine CO2 emission related to agricultural activities in peat soils. The research was conducted in peak of drought season, August, 2015 at Sungai Hitam, Bengkulu, Indonesia. In order to get representative sampling sites, field survey was conducted in May, 2015 in the research location. Primary data was collected from rice field, vegetables, bare land, and oil palm involved incubated CO2 emissions, peat thickness, and level of water tables. The data were analyzed statistically from 10selected samples of the rice fields, 7 selected samples of lowland vegetables fields, 3 selected samples of bare lands, and 8 selected samples of oil palm fields. CO2 emission values under the land on Sungai Hitampeat were as follow; 237.86, 238.57, 259.35, and 265.35 mg m-2 hr-1, respectively. Moreover, carbon releases based on peat thickness; <100, 101 – 150, 151 – 200, 201 – 250, and > 250 cm, respectively were 119.71, 189.35, 229.47, 288.58, and 297.59 mg m-2 hr-1. The trend of CO2 emission (y1) related to peat thickness (x1) fit with a following equation; y1 = 3.996x10.778; R2 = 0.953. Level of carbon emission affected by water tables; <100, 101 – 150, 151 – 200, and >200 cm, respectively was 192.80, 245.54, 292.21, and 309.97 mg m-2 hr-1. CO2 emission rate (y2) related to lowering water tables (x2) conformed to a following formula; y2 = 23.96x20.48; R2 = 0.949. Peat ecosystems sequestering carbonhave undegone for thousands of years. Therefore, cultivated peat for sustainable agriculture development should consider in managing peat thickness and water table.