Tuesday, June 12, 2012

IUCN Report Addresses Seagrass Carbon

IUCN Report: Mediterranean Seagrass Meadows - Resilience and Contribution to Climate Change Mitigation

Download at IUCN

Published by IUCN and produced by the IUCN Centre for Mediterranean Cooperation, this document is a short summary of a technical report on the current state of affairs in the Mediterranean basin and a must-read for policy-makers. Authors of the book place special attention to the impact of climate change on Mediterranean seagrass ecosystems and their role they play in mitigating the effects of climate change, in respect of extreme weather events and blue carbon sequestration. 

Key issues: 

What are the impacts of climate change on Magnoliophyta in the Mediterranean? “Mediterranean seagrass meadows reflect the history and biogeograhical diversity of this particular area”, says Alain Jeudy de Grissac, Coordinator of IUCN-Med Marine Programme. “Along with the disruptions brought about by many human pressures, climate change could lead to a general warming of the Mediterranean with ‘meridionalization’ or even ‘tropicalization’ depending on the sector, and to increasing frequency of the sea water events”. 

What is resilience? “This new concept represents an exercise in realism, aiming to accommodate the idea that ecosystems change within and between various stable states”, says Gérard Pergent, one of the study coordinators from Corse University (France). “Depending on the characteristics specific to the various species of Magnoliophyta found in the Mediterranean (physiological, biological and ecological), their resilience, adjustment stability and capacity to adapt may differ” 

How much seagrass may contribute to climate change mitigation? “Seagrasses play a significant but quantitatively moderate role in carbon sequestration globally. They are estimated to account for 40% of the carbon stored each year by coastal vegetation”, says Miguel Ángel Mateo, Centre d’Estudis Avançats de Blanes (CSIC-Spain) “ “It is the large carbon stock accumulated during thousands of years what makes seagrasses potentially highly valuable in the context of global warming. Specifically, it is estimated that Posidonia oceanica is retaining up to 89% of the total CO2 emitted by all Mediterranean countries since the Industrial Revolution.

- Posted by Sven Stadtmann, GRID-Arendal