Abstract
Accurate prediction for gas transport parameters, soil-gas diffusivity and air conductivity, is important to quantify methane emission from wetland. However, only limited measurements of gas transport parameters are available for peat soils. In this study, undisturbed soil cores were collected from a peat soil profile at the Bibai wetland, Hokkaido. Simultaneous measurements of volume shrinkage, soil-water retention curve, and gas transport parameters were carried out. The peat samples showed remarkable shrinkage following drainage, and the soil-gas diffusivity and air conductivity were greatly affected by pore structure change due to shrinkage. Examining pore structure indexes and water drainage from inner- and outer-pores in peat soil, changes in gas transport parameters can be classified into three stages with increasing in pF.