Linkages Between Amazon Mangrove Coastlines and Fluvial Sediment Exchange: How Climatic Variations Could Impact Mangrove Health

University Of Washington, Seattle WA

Investigators

Abstract

Mangrove forests are extremely valuable marine environments that protect human habitation against waves and currents, are themselves home to many juvenile marine organisms, and are major repositories for carbon. The mangrove coastlines south and north of the Amazon River mouth have had little impact from humans in terms of pollution or clear cutting, but reduction in sediment supply could expose mangrove forests to intense erosion from oceanographic forces. A doubling of eustatic (global) sea-level rise due to climate change could provide substantially more space to trap fluvial sediment discharge, perhaps doubling entrapment and further reducing the sediment supply to the ocean and coastal mangrove environments. To investigate this linkage between sea-level rise and mangrove health, a collaborative research network between US and Brazilian scientists will be established to supply the set of specialized skills necessary for this study. The US group brings expertise in sediment transport processes and the impacts of climate variations on river delta and coastal environments; off-shore research, and land-ocean interactions and global change. The Brazilian collaborators bring expertise in remote sensing, experience with mangrove coastlines, and coastal and estuarine circulation and sedimentological processes in the deltaic regions associated with the Amazon River. This project will entail a short course/technical workshop at Universidade Federal do Pará (UFPA); a preliminary field expedition to the Amazon tidal river and mangrove coastlines surrounding the river mouth; and the development of a communication network for sharing of scientific results and discussion. The short course and field expedition will involve a group of about 6 Brazilian and 6 U.S. students at the graduate and advanced undergraduate levels. The students will be exposed to the scientific underpinnings of fluvial and coastal sedimentation and the relevant environments through field excursions to the Amazon river mouth and coastal mangrove forests. This project and anticipated follow-on activities will lay the groundwork and create the international collaborations necessary to address the question of the linkages between sedimentological and geochemical processes operating on mangrove coastlines and fluvial sediment and carbon exchange to the coastal ocean.