Aplikasi Kompos Bungkil Jarak Pagar untuk Mereduksi Emisi Gas Rumah Kaca Karbondioksida (CO2), Metana (CH4) dan Dinitro-Oksida (N2O) dari Perkebunan Jarak Pagar

Abstract

Jatropha curcas cake compost application in agricultural practiced can increase soil organic carbon and improve amonification, nitrification and nitrogen fixation which good for plant. On the other hand, compost had potentially increase greenhouse gas (GHG) emission especially CO2, CH4 and N2O. This research was conducted to measure the GHG of this compost application and have been done in two steps. Firstly, clear the diurnal change in the GHG emission to determine the time of maximum GHG emitted to the air. It showed that the average concentration of CO2 and CH4 was higher during nighttime while N2O was higher during daytime. The maximum concentration of CO2, CH4 and N2O appears at 06:00 p.m. (354 ppm), 05:00 a.m. (5.4 ppm) and 04:00 p.m. (5.5 ppm). Secondly, identification of CO2, CH4 and N2O emission from compost application and compared to an-organic fertilizer (urea and slow release urea). The result showed that concentration of CH4 from Jatropha curcas cake compost was lower than urea at 3, 5 and 7 day after fertilization while N 2O from compost was higher at 3 and 14 day after fertilization. Urea application enhances CH4 emission by increasing metanogen activity. Meanwhile, addition of organic matter into soil caused oxygen deficiency and increase nitrate denitrification to N2O. Compared to slow release urea, CH4 concentration from compost was higher at 3, 5 and 14 day after fertilization. N2O from compost was lower at 5 and 14 day after fertilization. Calculation of total CH4 and N2O during 14 day showed that CH4 from compost was lower (621 mgC/m2) than urea (630 mgC/m2) and slow released urea (638 mgC/m2) while N2O from compost was highest (455 mgN/m2).