The potential of L‐band SAR for quantifying mangrove characteristics and change: case studies from the tropics

Abstract

Lucas, R. M., Mitchell, A. L., Rosenqvist, A., Christophe, P., Melius, A., Ticehurst, C. (2007). The potential of L-band SAR for quantifying mangrove characteristics and change: case studies from the tropics. Aquatic Conservation-Marine and Freshwater Ecosystems, 17, 245-264. Sponsorship: Environmental Research Institute of the Supervising Scientist (ERISS)1. The Japan Aerospace Exploration Agency's (JAXA) Advanced Land Observing Satellite (ALOS) L-band Phased Array Synthetic Aperture Radar (PALSAR), launched successfully in January 2006, will provide new data sets for coastal ecosystems mapping and change monitoring at local to global scales. 2. To evaluate L-band capability for mangrove applications, data acquired by the NASA airborne SAR (AIRSAR) and Japanese Earth Resources Satellite (JERS-1 SAR) over sites in Australia, French Guiana and Malaysia were used to demonstrate benefits for mapping extent and zones, retrieving biomass and structural attributes (e.g. height), and detecting change. 3. The research indicates that mapping is most effective where mangroves border non-forested areas and where differences in structure, as a function of species, growth stage and biomass distributions, occur between zones. 4. Using L-band SAR, biomass can be retrieved up to ?100?140 Mg ha?1, although retrieval is complicated by a noticeable decrease in L-band backscattering coefficient within higher (?>200 Mg ha?1) biomass stands, particularly those with extensive prop root systems. 5. Change detection through multi-temporal comparison of data proved useful for mapping deforestation/regeneration and mangrove dynamics associated with changing patterns of sedimentation. 6. The research highlights the likely benefits and limitations of using ALOS PALSAR data and supports JAXA's Kyoto & Carbon (K&C) Initiative in promoting the use of these data for regional mangrove assessment.Peer reviewe

Improving the Estimation of Above Ground Biomass Using Dual Polarimetric PALSAR and ETM+ Data in the Hyrcanian Mountain Forest (Iran)

“…RMSE decreases to 43.25 Mg/ha in this model (Table 8). Saturation of L-band that occurs at high AGB can explain the moderate correlation [15,19,22,88,89]. Results from ANOVA test (at 5% confidence interval) among P1-P5 models confirm that all of the models are significantly different from one another.…”

Object-Based Approach for Multi-Scale Mangrove Composition Mapping Using Multi-Resolution Image Datasets

“…The zonation pattern in Moreton Bay represents variations of Avicennia marina vegetation structure (i.e., canopy density, tree stem, tree height) across the mangrove stand. Hence, the mangrove zonation pattern differentiation based on image spectral reflectance suggested by Lucas et al [56] was not applicable in this case. To address this issue, in theory, the inclusion of textural or contextual information might help the classification.…”

“…From the field survey, it was established that these zonations represent a variation of canopy cover density, stem structure, dominant species, and tree height ( Table 2). Optical remote sensing data can often distinguish different mangrove zones based on the spectral reflectance of dominant mangrove species within each zone [56]. Multi-resolution segmentations with the scale parameters of 10 and 25 were applied to the AVNIR-2 and WV-2 image data, respectively, within the mangrove class to aggregate the zonation pattern.…”

Advanced Land Observing Satellite Phased Array Type L-Band SAR (ALOS PALSAR) to Inform the Conservation of Mangroves: Sundarbans as a Case Study

“…Change detection using both optical and radar data has previously been applied to mangroves, including those in the Sundarbans, Australia, South and Central America and southeast Asia [9,[36][37][38]. In this study, we use horizontal emitted, vertical received (HV) SAR data from ALOS/PALSAR scenes for change detection.…”