Response of temperature, moisture and CO2 emission from different water levels at undisturbed peat soil column

Abstract

Greenhouse gas (GHG) emissions from peatlands are influenced by many factors and most of them are difficult to control. Soil temperature and moisture regulate biological reactions in the soil leading to gas production. It is a complex mechanism, considering the difficulty in controlling soil moisture and temperature. The study aimed to assess the consequence of soil moisture and temperature alteration on Carbon Dioxide (CO2) emission through water level management. Soil samples were collected using a 21 cm (diameter) and 100 cm (length) of polyvinyl chloride (PVC); each was dipped into big bucket to control water level. Water levels were controlled in daily basis. Three different water levels were arranged, i.e., at 15 cm, 35 cm and 55 cm beneath earth surface and were replicated 3 times. The results showed that water levels affected soil and water temperature. Non-linear relationship between temperature and CO2 emission (P < 0.01) was discovered in this research. The lowest soil moisture was recorded at -55 cm water level below surface, then by experiments at -35 cm and -15 cm water levels. Lower water level increased aeration of peat soil and created optimal conditions for microorganisms to oxidize organic matters that produced and emitted CO2 into the atmosphere.