The Effect of Canal Distance on the Groundwater Level Dynamics at Burned Peatland in Limbung Village, West Kalimantan

Watershed Management Laboratory, Department of Forest Resources Conservation, Faculty of Forestry, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia

^* Corresponding author: hsuryatmojo@ugm.ac.id

Abstract

Peatlands have hydrological functions, one of which is water storage. Limbung Village experienced peatland fires, and there was drainage (canal). This research aims to determine the characteristics of peatland, the dynamics of groundwater levels, and the groundwater level response in the burned peatland. The study was carried out from September to December 2023 by measuring groundwater levels using monitoring wells, heavy rain using a rain gauge observing characteristic peat soil, and vegetation observations were made with a PSP size of 25 × 80 m. An analysis of the influence of rain thickness on the increase in GWL was carried out to understand the effect of canal distance on GWL dynamics using simple regression analysis. Results of the research show that the peat groundwater level has a high rain intensity of >43.64 mm, which is needed to increase the GWL. The response to the increase in GWL occurs more quickly at a distance of 20 m from the canal, compared to 3 points following response begins to decrease drastically starting from a distance of 70 m from the canal. Low vegetation density, soil characteristics, and the condition of the canal blocking cause different responses.