Electrical resistivity imaging of mangrove sediments, northern Taiwan

Mangrove sediments are natural carbon sinks that may act as key components for climate change mitigation. To investigate the characteristics and distribution of the carbon-dense muds in the coastal mangrove areas of northern Taiwan, we applied both floating and submerged electrodes for subsurface resistivity imaging. After collecting the apparent resistivity data, we conducted 2D resistivity inversion and 3D modeling. Our results show that the muddy sediments are characterized by low resistivity and are primarily found in the top ten meters below the riverbed. On the other hand, a higher resistivity layer, probably indicating coarse-grained sediments, is situated below the muddy layer. Although the submerged electrodes generally provide the best data quality, the floating electrodes efficiently image the bottom of the muddy sediments. Therefore, we recommend that a combination of floating and submerged electrode methods for resistivity imaging should be an efficient approach to investigate mud distribution in mangrove sediments with shallow water depths.