BIOdiversity and ecosystem functioning of MANgroves in French Guiana: prospects for ecOsystem management in the Amazonian system – BIOMANGO

- complementarity between disciplines
- functional approach of the biodiversity
- in situ techniques for observation and experimental

in progress

next field work expected for 2015 to experimentally study biodiversity effect on biogeochemical functions in mangroves

- A. Aschenbroich, T Stieglitz, F Fromard, G Thouzeau, RC. Aller, M Tavares A Gardel, E Michaud. 2015. Mangrove crabs and their burrows – key players in benthic processes in mangrove ecosystems. 2015 Aquatic Sciences Meeting. Aquatic Sciences: Global And Regional Perspectives — North Meets South. 22-27 February 2015, Granada, Spain.
- A. Aschenbroich, E Michaud, F Fromard, LF Daigle, B Long, G Thouzeau. 2015. CT-Scan analysis of bioturbation structures: from intertidal mudflat to young mangrove forest in French Guiana (South America). 2nd International conference on tomography of material and structures. June 29th – July 3rd, Québec, Canada.
- A. Aschenbroich, E. Michaud, F. Fromard, F. Gilbert, G. Thouzeau. Investigating the changes in benthic macrofauna community structure and bioturbation during mudflat colonization by mangrove. 5th Nereis park Conference, 5-7 juillet 2014, Plymouth, Angleterre.
- Sciences Ouest, Mars 2015, numéro 329. Une biodiversité utile à la mangrove.
- CNRS International Magazine, winter 2015, number 36. Why Mangroves matter – Mangroves: an asset to treasure.
- CNRS Le Journal, janvier 2015. L’inquiétant recul des mangroves.
- www.guyane.cnrs.fr/spip.php,
- www.guyane.cnrs.fr/spip.php
- www.guyane.cnrs.fr/spip.php
- pôle-relais Mangroves et Zones humides d’outre-mer – Ifrecor – Conservatoire du Littoral : www.pole-zh-outremer.org/projets/projet-biomango-biodiversite-et-fonctionnement-des-ecosystemes-dans-les-mangroves-de-guyane-francaise/
- Emission Radio Guyane 1ère (08/10/2013)
- Emission TV « le Monde de Jamy » diffusion programmée le 15 juillet 2015 sur France 3
- Plaquette « Programme Culture Scientifique 2014 -2015 (15 000 exemplaires) et éducative « A l’école des océans » 2013 – 2014 – 2015 (30 000 exemplaire)

Mangrove forests are highly productive coastal ecosystems and stimulate carbon and nutrient cycles in coastal areas. Mangroves play a key role in the functioning of coastal ecosystems and provide ecological services and socio-economic irreplaceable value. Benthic biodiversity plays a key role in stimulating and maintaining this productivity through the activities of bioturbation. Mangroves are set to disappear with human pressure and climate change. In French Guiana (FG), mangroves are subjected and adapted to recurring sedimentary disturbances along the coast of Guiana due to the massive sediment supply from the Amazon. Five mangrove facies are established: emergent mud bank, mangrove pioneer, young forest, mature forest, forest senescent. Adult mangroves stabilize the coast but during mud bank erosive phases, forests are destroyed. During the accretion phase of mud banks, mangroves are able to develop very rapidly and are characterized by high productivity. The first data acquired on the benthic system indicate that mangroves are adapted to these phases of stability and instability; pioneer species in high density occur in unstable sediments with low species richness. Current studies in ecology show that the productivity of an ecosystem (respiration, primary production, mineralization capacity) is not dependent on its species richness but on functional richness, which in benthic systems can be represented by key functional groups of bioturbating organisms. The role of benthos and associated bioturbation activity on the productivity of mangroves in French Guiana is still unknown. Given the high productivity of mangroves in French Guiana and solid basic background knowledge of the environment, studies on the relationships of biodiversity to ecosystem functioning must now be addressed. The resilience of mangroves in French Guiana is a key to the structuring and functioning of the ecosystem and must be fully understood to develop a strategy for management and conservation of the coastline in this environment still only minimally disturbed by human activity. The project BIOMANGO proposes to define the basis for resilience by studying: 1) in situ spatio-temporal variability of benthic biodiversity (microphytobenthos and fauna) in response to biotic and abiotic factors, 2) in situ spatio-temporal variability of biogeochemical fluxes corresponding to the different stages of the mangrove development and associated benthic biodiversity, and 3) in vitro role of the impact of bioturbation functional diversity on ecosystem functions. The project BIOMANGO will use multidisciplinary approach and methods to test for possible relationships between benthic biodiversity and productivity of mangroves. Specific scenarios will be evaluated based on the initial observations of the project. The final results will establish a baseline of functioning of mangrove ecosystems of FG, which will reveal ecosystem services that may be lost under the increasing human pressure (i.e., case of oil pollution). BIOMANGO will fuel both theoretical and management models to understand the relationship between biodiversity and functioning of mangrove ecosystems. The study area chosen is known to be difficult to access, and the logistics are already coordinated. The implementation of this project will be enhanced by national and international collaboration (NSF) within the same study area, including the coordinators involved in BIOMANGO. The results of this project will not simply be disseminated through traditional scientific publications, but also through educational workshops offered at French schools in collaboration with an innovative team skilled in scientific communication.