Key for peatland management is a deep understanding of the hydrological processes and phenomena in peatland such as water flow in the biosphere, leaf, stem, and root. Relationships between groundwater level (GWL), rainfall, and evapotranspiration are also the key elements. Soil moisture near the peatland surface is clearly affected by the vegetation types in peatland. An important indicator of peatland hydrology, i.e. hydraulic conductivity, is theoretically explained in this paper, including its behavior. Horizontal groundwater flow in a saturated peat layer is caused by horizontal difference of water potential, for which the understanding of groundwater flow, speed, and direction were measured. The canal construction in peatland is the most typical disturbance in a peatland ecosystem. The groundwater flow near the canal in the tropical peatland of Central Kalimantan suggested the presence of high permeable layers in the peat soil near the weir.
