Modelling hydrological responses of a peatland to disturbance by geologic exploration

The slow recovery of trees in peatlands disturbed by linear clearings that arise from geologic exploration, also known as seismic lines, has spurred scholarly investigation into the underlying factors. The effect of tree canopy removal on the line on local water balance is one of the unanswered questions in past studies. Hence, this study aimed to provide insights into the impact of seismic lines on water balance components using CoupModel. Simulated values were compared with field measurements from a seismic line located in Fort McMurray, Alberta, Canada. The simulations indicated an increase in precipitation, soil moisture and temperature, and snow depth on the seismic line compared to undisturbed conditions with results aligned with the field measurements. Simulations also showed that the snow density on the seismic line was 4.6 % higher than the adjacent natural area (herein referred to as offline). Furthermore, the predicted shallower groundwater depth on the line was consistent with the observations. Although simulated net radiation off the line was higher than on the line, the actual evapotranspiration (AET) on the line was 8.3% higher than off the line. It was also found that evaporation from moss is the dominant component of the AET from the seismic line and adjacent natural area. However, greater precipitation inputs due to reduced interception outweighed the high AET on the seismic line, so that the seismic line had higher water storage than off the line by 38%. Sensitivity indicated the importance of site location (i.e., latitude), soil physical properties, and leaf area index parameters in simulations.  As a consequence, the initial model of water balance necessitates future researchers to explore the impact of different seismic lines, particularly at the catchment scale, to better understand the cumulative impact of these disturbances on water balance in boreal ecosystems.