The Intergovernmental Panel on Climate Change found that the agriculture sector is accounted for from 10 to 12 percent of anthropogenic global emissions. Indonesia, known as a maritime and agricultural country, also has a contribution to this emission especially on peatland agriculture. The practice was blamed for the source of high greenhouse gas (GHG) emissions.
However, it is debatable, some scientists believe the source of emission, others have found proof the agricultural sector also sequesters carbon in the atmosphere. Since 2020, Tay Juhana Foundation (TJF) has tried to provide scientific evidence about sustainable agricultural practices that low GHG emissions. To provide comprehensive results, we have collaborated with experts from IPB University. On 6 to 12 November 2021, TJF and the experts visited our study site on peatland coconut plantation in Pulau Burung District, Riau Province.
On the first day, we employ discussion about initial research finding (figure 1). We found, the emission from peatland soil is same as in the mineral soil. What make it different is the vegetation, as productivity increase it will increase carbon emission from vegetation respiration. Not from soil oxidation of peat soil as we believe previously.
The next following days, we visited carbon measurement sites. We conducted CO2 flux measurement for six month to measure actual emission from soil. From this expert visit, we obtained two scientific findings.
First, a stable water table level produces a balanced condition for coconut to optimal growth in peatland utilization. In other areas, high deviation of water table from dry and wet season damage the peat soil and lower productivity. Also the transition peat age, from intermediate to sapric (from organic decomposition to true form of soil) questions other experts about the peat oxidation source of emission; because sapric soil is already mature soil and dont have bacteria to initiate oxidation. so the key land management belongs to peatland water management.
Second, the weeding activities (removing unwanted plants below coconut canopy) is by manual (cutting the weed) and not using herbicide and fire. As a result, the decomposed material from weeds has become fertilizer material for coconut. and from the soil layer, it creates an organic layer above peat soil (figure 2).