Summary: | In the past three decades, peatlands all over the world such as upland bogs, tropical fens, have been undergoing significant and rapid degradations. These degradations cause carbon loss and CO2 emissions, and also fuel climate change. In this research, I present three case studies on how space geodetic tools, especially Radar Interferometry (InSAR), can be used to monitor and to advance our understanding of the long-term surface changes in peatlands. First, I investigate the eroding extent and severity of upland UK peatlands using InSAR. Both short wavelength C-band and long wavelength L-band data are explored in this study. I detect a long-term peat subsidence rate of about 0.3 cm/yr, and 2 cm of decrease in peat height between 2002 and 2010. I also examine the coherence performance of C- and L-band over upland bogs. I find L-band data provides better coherence than C-band in upland bogs. Second, I use InSAR time series generated by L-band images to map the spatial and temporal subsidence of drained tropical peatlands in Sumatra, Indonesia. And based on InSAR-derived subsidence rate data, I estimate carbon loss or CO2 emission. Third, I assess the effectiveness of peatland restoration work in in Central Kalimantan, Indonesia using InSAR (L-band images). Restoration effects and impact factors are investigated by the spatial and temporal changes of peat height, which also provide useful information for guiding future restoration activities in this region. Overall, this research suggests that InSAR time series is feasible to monitor long-term peat height change in peatlands, provides new insights into the dynamic surface changes in peatlands, and helps to study the carbon loss and CO2 emissions from peatlands, and understand restoration effects.
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