Influence of Oil Palm Plantation Age and Hydrology on Dissolved Organic Carbon Concentration of Malaysian Tropical Peatland Water Resources

Abstract

Due to boom recorded globally in oil palm industries, many palm oil producing countries like Malaysia and Indonesia converted the sizeable parts of their carbon-rich previously stable peat swamp forests to oil palm plantation. This conversion resulted in huge loss of the soil carbon in dissolved and gaseous forms to atmospheric body and nearby streams. This paper thus focuses on assessing the influence of oil palm plantation age and hydrological factors on dissolved organic carbon concentration in the tropical peatlands. Four different plantations were considered with different years of peat swamp forest conversion ranging from 2000, 2002, 2006 and 2010. The plantation tagged 2010 was first cleared in 1978 and hereby referred to as 2010/1978 in this study. Two tube wells were installed in each of the plantations for monitoring DOC concentration of groundwater between September 2013 and December, 2014. The results showed positive influence of heavy storm events on DOC concentrations and that the lowest DOC concentration ranging from 18.10 mg/L to 28.60mg/L was observed at 2010/1978 plantation as against the highest DOC concentration of range 169.2 mg/L to 250.50 mg/L at 2000 plantation. The results therefore justify the influence of age of plantation as 1978/2010 plantation recorded the lowest DOC concentration as against the 2000 plantation recording the highest DOC concentration. It is thus recommended that oil palm cultivation on peatlands should be avoided as this practice, if not well-managed, leads to flux and emission of stored soil carbon in both dissolved and gaseous forms to the surrounding water resources and atmospheric body.