Prediction of Greenhouse Gases and Global Warming Potential in Agricultural Lands of Khuzestan Province Using DAYCENT Model

In the current years, increase of greenhouse gas emissions such as methane (CH4), nitrous oxide (N2O) and nitric oxide (NO) from soils to atmosphere is a global concern. Tillage and agricultural lands deveopment have been the main sources of greenhouse gases production. The aim of this study is to determine the rate of greenhouse gas emissions in agricultural lands of Khuzestan province using DAYCENT model. For this purpose, the rate of gas emmission from the soil surface was measured in each agricultural unit. Also, the emmission of methane, nitrous oxide and nitric oxide gases were estimated in agricultural ecosystems of Khuzestan province, using DAYCENT software. The global warming potential was determined for all the study areas. The highest methane emission (1.369 tons/ha) was estimated by DAYCENT model which corresponded to the paddy fields of Baghmalek. Also, the highest emission of nitrous oxide and nitric oxide were corresponded to Shush wheat fields with 0.101 and 0.111 tons per hectare per year, respectively. The maximum global warming potential (66.664 tones equivalent to carbon dioxide) was determined based on DAYCENT data which was corresponded to Shush wheat fields. The results showed a lower gas emissions and heating potential in sugarcane fields as compared to the other cultivars. Also, according to the statistical indicators of determination coefficient (0.98, 0.99 and 0.77), root means square Error (0.05, 0.31and 0.03) and model efficiency (0.61, 0.85 and 0.76), respectively for three gases of nitrous oxide, methane and nitric oxide, DAYCENT model showed an acceptable accuracy.