Eleven Years of Mangrove–Mudflat Dynamics on the Mud Volcano-Induced Prograding Delta in East Java, Indonesia: Integrating UAV and Satellite Imagery

Abstract

This article presents a novel approach to explore mangrove dynamics on a prograding delta by integrating unmanned aerial vehicle (UAV) and satellite imagery. The Porong Delta in Indonesia has a unique geographical setting with rapid delta development and expansion of the mangrove belt. This is due to an unprecedented mud load from the LUSI mud volcanic eruption. The mangrove dynamics analysis combines UAV-based Structure from Motion (SfM) photogrammetry and 11 years (2009–2019) satellite imagery cloud computing analysis by Google Earth Engine (GEE). Our analysis shows unique, high-spatiotemporal-resolution mangrove extent maps. The SfM photogrammetry analysis leads to a 3D representation of the mangrove canopy and an estimate of mangrove biophysical properties with accurate height and individual position of the mangroves stand. GEE derived vegetation indices resulted in high (three-monthly) resolution mangrove coverage dynamics over 11 years (2009–2019), yielding a value of more than 98% for the overall, producer and consumer accuracy. Combining the satellite-derived age maps and the UAV-derived spatial tree structure allowed us to monitor the mangrove dynamics on a rapidly prograding delta along with its structural attributes. This analysis is of essential value to ecologists, coastal managers, and policymakers.

Mangrove Above-Ground Biomass and Carbon Stock in the Karimunjawa-Kemujan Islands Estimated from Unmanned Aerial Vehicle-Imagery

“…Almost along the southwestern and northeastern wings coastline, the Lorey's height reaches more than 8 m. At the tail area, which is also bordered by the sea, the Lorey's height also reaches more than 8 m. Overall, we can see the clear border forming the narrow band of high Lorey's height facing the seaside. These heights are comparable with mangroves found in most areas in Indonesia, such as Bali [51], Porong Delta, East Java [52], Mahakam Delta [25], etc. But they are too short compared to the mangrove height in Papua, which can reach more than 40 m high, e.g., [25,53,54].…”

Nature-Based Engineering: A Review on Reducing Coastal Flood Risk With Mangroves

“…Bhargava et al (2021) applied remote sensing to observe the extent of the water surface and thus the topography relative to the water level. Additional morphological features, such as the presence of creeks or the intertidal topography in mangroves, have been obtained with (1) airborne or spaceborne remote-sensing with lidar (Zhang et al, 2008;Montgomery et al, 2018) or radar (Kuenzer et al, 2011), (2) fieldscale remote sensing with drones (Beselly et al, 2021) and ( 3) field monitoring with RTK GPS and/or Total Station (Horstman et al, 2015;Leong et al, 2018;Walcker et al, 2019) or levelling tubes (Quartel et al, 2007;Van Santen et al, 2007). It is generally challenging to obtain topographic measurements in mangrove forests, as direct measurements are hampered by the dense vegetation and RTK GPS as well as remote sensing are affected by the tree canopy.…”

UAV Photogrammetry in Intertidal Mudflats: Accuracy, Efficiency, and Potential for Integration with Satellite Imagery

“…[19,31,32] Despite the great potential of UAV-based SfM photogrammetry in monitoring intertidal topographic dynamics, there are some fundamental issues regarding the resultant topographic accuracy that have not been fully studied. First, SfM reconstructs the threedimensional structure of a scene or object from a series of overlapping images acquired from different perspectives [33,34]. The selection of different flight parameters (e.g., flight pattern, altitude, and overlap) not only affects the efficiency of the aerial survey but also could lead to significant differences in the accuracy of the photogrammetric results.…”