Effect of peat water levels on greenhouse gas production in different cropping land use

Degraded peat has a high potential for use in agricultural production, especially food crops. The water table, which impacts the production of greenhouse gases (GHGs), is the main problem concerning peat utilization. The study aimed to determine the production of greenhouse gases at various peat water levels. The study was conducted in a laboratory setting utilizing the soil column of undisturbed peat soil. The factorial experiment was arranged in randomized block design, with three replicates, with the first factor was peat cropping use: Maize (Zea mays L.), pineapple (Ananas comosus (L.) Merr.), and scrubs. The second factor was water level (0, 10, 20, 30 cm depth). Variables measured were GHG flux (C[O.sub.2] and [CH.sub.4]), pH, redox potential, total C content, and ash content. The peat cropping use interacted significantly with the peat water level on the potential for [CH.sub.4] and C[O.sub.2] production and the value of global warming potential. Water table depth significantly increased C[O.sub.2] flux and global warming potential (GWP) in all three peat cropping uses. The lowest GWP at a 0 cm peat water level was 944 (pineapple use), 961 (maize use), and 1097 mg C[O.sub.2]e [m.sup.-2] [d.sup.-1] (scrub use). Peat for pineapple cultivation produces the lowest C[O.sub.2] production and GWP compared to maize cultivation and scrubs. The negative relationship between redox potential and GWP is significant in peat for scrub. The relationship between pH and GWP is significant in peat for pineapple and scrub. Key words: Carbon dioxide, global warming potential, methane, peat soils, water level.