EFFECT OF SOIL AND FERTILIZER TYPES ON GREENHOUSE GAS EMISSIONS AND PLANT GROWTH IN OIL PALM PLANTATIONS

摘要

Oil palm plantations have been reported to release large quantities of N2O into the atmosphere, most likely linked to nitrogen fertilizer use. This study aimed to evaluate the effects of soil types in comparison peat soil with others and nitrogen fertilizer on N2O and CO2 emissions in oil palm plantations. Field experiments were conducted in sandy loam soil (7 years oil palm), sandy soil (9 years oil palm) and peat soil (5 years oil palm) from 2010 to 2013 treated with coated fertilizer and conventional fertilizer. N2O and CO2 fluxes showed high variations with seasons, types of soil and fertilizer treatments. The N application rate of coated fertilizer was about half that of conventional fertilizer and was applied as deep placement. The vegetation and yield were no significant difference among treatments. To get rid of previous dosage of fertilizer, cultivation test of immature trees (2 years oil palm) was done with coated fertilizer and conventional fertilizer in peat soil and sandy loam at the same plantation from 2011 to 2015. The N application rate of coated fertilizer was as same as that of convention fertilizer and half of that. Measurement of actual nitrogen release from coated fertilizer in the field was also evaluated from 2011 to 2013.