Looking at the peat from above: application of Interferometric synthetic aperture radar to detect peatland subsidence in the Biebrza Valley

Abstract

This study presents an analysis of peatland surface height changes in the Biebrza Valley, Poland, using the Alaska Satellite Facility (ASF) Interferometry Synthetic Aperture Radar (InSAR) on-demand cloud computing via Small Baseline Set (SBAS) technique and seasonal-annual search approach. The dataset covers the period from April 2015 to April 2022. The findings reveal a consistent rate of peatland subsidence, calculated to be 1.25 cm per year, which was validated through field surveys. The statistical analysis demonstrates the dataset’s robustness, with an R2 value of 0.94, indicating a strong correlation, while the low RMSE value of 0.23 cm suggests minimal error. The negative Pbias value of -33.6 indicates a tendency towards overestimation of the measured subsidence values. These results indicate the high precision and accuracy achieved by the InSAR products generated by the ASF DAAD HyP3 platform, providing reliable measurements at the millimeter level. Considering the extensive area of the Biebrza National Park, covering 59,717 hectares, the estimated annual volume loss of peatland is projected to reach approximately 7,500,000 cubic meters based on the observed rate of subsidence. These findings underscore the significant impact of peatland degradation and emphasize the need for continued research and proactive measures to mitigate such effects.