Across their range and particularly in recent decades, mangroves have experienced significant loss and degradation through human activities (e.g., clearance or degradation), and have induced coastal and climate change. These changes and the impacts on the coastal environment are particularly noticeable in time-series of remote sensing data. The remote sensing community has reported on such changes at varying (local to global) scales and temporal frequencies and using a diverse range of sensors (primarily optical, radar, and lidar). However, despite alerting communities at all levels to such changes, mangroves continue to be lost or degraded to the point that there are now large sections of coastline with very little of this ecosystem remaining. Such losses are devastating to both floral and faunal diversity, and significantly compromise the integrity and functioning of coastal environments. Moreover, there are significant impacts on societies living close to or relying on mangroves, and also on local to national economies.
Without multi-scale Earth observations, there is no doubt that the community would be far less aware of the changes in mangroves that have occurred, and of the extent of the damage inflicted. However, we can do more, but this requires the whole community to engage and collaborate in a way that ensures that local to international policymakers, land managers, and communities are provided with robust datasets that routinely capture and can be used to report—on a timely and regularly basis—the states and dynamics of mangroves at local to global scales.
The Special Issue “Ensuring a Long-Term Future for Mangroves: A Role for Remote Sensing” in Remote Sensing aims at highlighting research that explores the following:
- How the characterizing, mapping, and monitoring of mangroves can be consistently coordinated, from local to global scales, such that the various datasets generated build on and align with each other, particularly in terms of mapped extents, class taxonomies, and biophysical attributes (e.g., height, cover, and biomass).
- How in situ (field) data coupled with very high spatial resolution airborne (including drone) and spaceborne images can support the development products and build sound baselines dedicated to emblematic topics such as, “mangroves for sustainable aquaculture” or “mangroves for early warning on coastal erosion”, which can be addressed and managed at national and international levels.
- How the development of algorithms and models for explaining changes along coastlines supporting mangroves as a function of forcing variables (climate, ocean, and human activities) can prefigure the dynamic and reliable classifications of coastal land cover change and evolution.
- How the transboundary issue of mangrove preservation can benefit from centralized repositories with freely available data at a global level.
- How local communities can be made increasingly aware of and become involved in the sustainable and equitable management of “their” mangrove region through new technologies including mobile phone applications, web-portals alimented by image data and dynamic land cover maps.
Prof. Richard Lucas, Dpt. of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, Ceredigion, United Kingdom
Dr. Christophe Proisy, Dpt. of GeoSpatial Monitoring and Information Technology, French Institute of Pondicherry, Pondicherry, India
Deadline for manuscript submissions: 30 January 2020