The organic carbon dynamics of peat soil under liberica coffee cultivation

Abstract

The exploitation of peat soil considered enrich CO2 gas emissions in the atmosphere and contribute to global warming. The farmers in Jambi and Riau province have been cultivated Liberica coffee on peat soil since 1940. This study evaluated the effect of Liberica coffee cultivation to peat carbon conservation. The study was arranged as an observation method at the Liberica coffee tress aged 1) 4-6 years (young productive plants) and 2) > 10 years (mature productive plants). Each observation consisted of 16 trees. The results showed that the average CO2 emissions from the peat cultivated Liberica coffee around 23.7 Mg CO2/ha/year, while it from peat soil under natural forests were reported to be 20-40 Mg CO2/ha/year. The litters of the productive Liberica coffee trees return organic C to the peat about 0.35 to 4.7 Mg/ha/year. Compost of 13.5 Mg/ha of Liberica coffee cherries cascara and parchment, applied by farmers as a fertilizer also returned 7.38 Mg/ha/year of organic C, while the number of organic C carried by 1.5 Mg/ha/year of the Liberica coffee green beans was only 825 kg/ha/year, approximately. This study showed that the Liberika coffee cultivation on peat soil is a safe way to conserve C in peat soil.