IRDIRD


Cyril MARCHAND

Telephone:

687 26 07 80

Fax:

687 26 43 26

Email:

cyril.marchand@ird.fr

Postal Address:

IRD

 

 

BP A5, 98848 Nouméa,

 

 

Nouvelle Calédonie

 

Office No.:

69

 

Activities

2000-2003: Ph.D. student, Institut des Sciences de la Terre  d'Orléans (UMR 6113, CNRS-UO), Organic matter dynamics in the mangroves of French Guiana

2004: Post-doctoral fellow, Institut des Sciences de la Terre  d'Orléans (UMR 6113, CNRS-UO), Carbohydrates and lignin diagenesis in the mangroves of Guadeloupe

2005-2006: Post-doctoral fellow, LGPMC, University of New-Caledonia, Relationships between heavy metals distribution and organic matter diagenesis in the mangroves of New-Caledonia

Since October 2006: IRD scientist, Organic matter and heavy metals dynamics in the mangroves of New-Caledonia

Research Interests

Resulting from demographic increase, urbanization, expansion of industrial activities, natural resources prospecting and exploitation, the biodiversity of coastal environment, which hold importance regarding ecology and economy, is threatened. Mangrove forests are specific coastal wetlands, having a high adaptation capacity to extreme environmental conditions, e.g. hypersalinity, waterlogging, contrasting redox conditions, substrate instability. Mangroves develop on almost 75% of tropical and subtropical coastlines, where they cover ca. 200,000 km2 (Day et al., 1987). Mangrove forests are constituted of ±19 flowering plant families, decomposed in ± 27 genera and ±70 species (Ellison and Farnsworth, 2001). These forests are among the most productive terrestrial ecosystems with a total net primary production that can be estimated up to 149 mol C m-2 y-1 (Kristensen et al., submitted). As a consequence, mangroves are considered to have a high impact on the global carbon cycling. Additionally, mangroves support coastal food webs. Waters bordering on mangroves are generally rich in fishes and shrimps. A recent study demonstrate that up to 10% of terrestrial DOC present in the ocean are produced by mangrove forests, while they represent only 0.5 % of land surface (Dittmar et al., 2006).  Additionally, mangrove forests significantly reduce coastal erosion (Wolansky, 1992; Furukawa et al., 1997, Wong, 2003) and may provide protection from tropical cyclones and tidal waves (Dahdouh-Guebas et al., 2005). Finally, mangroves shelter an important animal biodiversity, notably macrobenthos.

Regrettably, mangrove forests are currently disappearing at 1-2 % per year, a rate greater than or equal to that of coral reefs or inland tropical rainforests (UNEP-WCMC, 2006; Valiela et al. 2001, Wilkie and Fortuna 2003). This destruction occurs all around the world, and particularly in developing countries, where 90% of mangrove areas are found. During the last 30 years, estimations of mangrove loss ranged from 35 to 86 % (Wilkie and Fortuna 2003). Mangroves destruction not only threatened mangrove biodiversity but also the biodiversity of associated ecosystems, notably the adjacent coral reefs. One threat on mangrove forest is trace metals pollution. Resulting from their richness in organic matter, and the variability of redox processes that occur in mangrove sediments, mangroves are preferential zone for the accumulation of heavy metals (Harbison, 1986). In this specific ecosystem, heavy metals dynamic is intimately linked to the one of organic matters that are ubiquitous.  Actually, heavy metals can be physically or chemically associated to organic matter by complexation/chelation/adsorption (Nissenbaum and Swaine, 1976; Wood, 1996). Additionally, their accumulation in high quantity can strongly modify mangrove sediments geochemistry and thus may influence mangrove biodiversity.

The main objectives of our current research are:

- to understand the relationships between substrate geochemistry and mangrove biodiversity,

- to assess the processes that link heavy metals distribution to organic matter dynamic in the ecosystem,

- to model the evolution of biodiversity with increasing anthropogenic pressure.

To reach our goals, we are working on a pluridisciplinary way (botanic, biogeochemistry, mineralogy, ...) in two times and on various sites subjected to different anthropogenic pressure. First, we are interested in the biogeochemical processes that control heavy metals dynamic (Fe, Mn, Cr, Ni, Co) among the three compartments constituting the ecosystem (sediments, waters, and mangrove plants).  Secondly, we would like to quantify heavy metals and organic matter fluxes on a transect from catchments through mangroves and to coastal ocean, to assess their possible role as sink. This research is currently conducted in New-Caledonia. The main specificity of the mangroves developing in New-Caledonia is their association with the world’s longest continuous barrier reef, which delimits a lagoon of more than 20,000 km2. Mangrove swamps cover 80% of the island eastern coastline and nearly 20% of the western’s. As a consequence, they represent one of the main nutrients source to the lagoon. In addition, they act as a buffer between the lagoon and the land, which is characterized by its richness in nickel. Currently, New Caledonia is the third nickel producing country in the world. Since the beginning of the activities at the end of the 19th century, almost 300 millions of m3 of laterites enriched in Fe, Mn, Ni, Cr and Co have been extracted. Processes of erosion and sedimentation, which naturally occur, are strongly emphasized by mining activities. As a consequence, a significant part of these materials has been transported by erosion to the coastal zone, where they can accumulate. Additionally, New-Caledonia is frequently subjected to tropical cyclones (in 25 years, 6 cyclones on the south of the island and 11 on the north). Processes of erosion and sedimentation are strongly increased during tropical cyclones, and represent the most important degradation of coastal zone, including mangroves and reefs. As a consequence, mangroves of New-Caledonia represent an extraordinary natural laboratory to study the anthropogenic influence on mangrove biodiversity.

 

Publications

International journals

9- Marchand, C., Lallier-Vergès, E., Disnar, J.-R., Kéravis, D., 2008. Organic carbon sources and transformations in mangrove sediments: a Rock-Eval pyrolysis approach. Organic Geochemistry 39, 408-421. [pdf]

8- Bouillon, S., Borges, A. V., Castañeda-Moya, E., Diele, K., Dittmar, T., Duke, N. C., Kristensen, E., Lee, S. Y., Marchand, C., Middelburg, J. J., Rivera-Monroy, V. H., Smith III, T.J., and Twilley, R. R. 2008. Mangrove production and carbon sinks: a revision of global budget estimates. Global Biogeochemical Cycling 22, GB2013. [pdf]

7- Kristensen E., Bouillon, S., Dittmar, T., Marchand, C.. in press. Organic carbon dynamics in mangrove ecosystem. Aquatic Botany. [pdf]

6- Duke, N. C., Meynecke, J.-O., Dittmann, S., M. Ellison, A., Anger, K., Berger U., Cannicci, S., Diele, K., Ewel, K. C., Field, C. D., Koedam, N., Lee, S. Y., Marchand C., Nordhaus, I., Smith III, T. J., Dahdouh-Guebas, F. 2007. A world without mangroves? Science 317, 41-42. [pdf]

5 - Marchand, C., Albéric, P., Lallier-Vergès, E., Baltzer, F. 2006. Distribution and characteristics of dissolved organic matter in mangrove sediments pore waters along the coastline of French Guiana. Biogeochemistry 81, 59-75. [pdf]

4 - Marchand, C., Lallier-Vergès, E., Baltzer, F., Alberic, P, Cossa, D., Baillif, P. 2006. Heavy metals distribution in mangrove sediments (French Guiana). Marine chemistry 98, 1-17. Top 10 most requested paper Marine Chemistry 2006. [pdf]

3 - Marchand, C., Disnar, J-R., Lallier-Vergès, E., Lottier, N. 2005. Early diagenesis of carbohydrates and lignin in mangrove sediments submitted to variable redox conditions (French Guiana). Geochimica et Cosmochimica Acta 69, 131-142. [pdf]

2- Marchand, C., Baltzer, F., Lallier-Vergès, E., Albéric, P., 2004. Pore water chemistry in mangrove sediments: relationship with species composition and developmental stages. (French Guiana) Marine Geology 208, 361-381. Top 25 most requested paper Marine Geology 2004. [pdf]

1- Marchand, C., Lallier-Vergès E. and Baltzer F. 2003.The composition of bulk sedimentary organic matter in relation to the dynamic features of a mangrove-fringed coast in French Guiana. Estuarine Coastal and Shelf Sciences 56, 119-130. [pdf]

Congress

11- Lallier-Vergès, E., Marchand, C., Albéric, P. (2007) Impact of organic matter decomposition on heavy metal distribution in mangrove sediments (French Guiana). EGU, Vienna, Austria, 15 – 20/04/07

10- Marchand, C.,  Allenbach, M.,  Baillif, P.,  Hoibian, T.  Albéric, P.,  Lallier-Vergès E. (2006) The fate of organic matter and heavy metals in an urban mangrove swamp, Nouméa, New Caledonia. Society of Wetland Scientist, Cairns, Australia, 5-9/07/06.

9  - Marchand, C.,  Lallier-Vergès, E.,  Baltzer, F. , Disnar J.-R. (2006). Organic matter dynamics in an Avicennia germinans mangrove swamp (French Guiana). Mangrove Macrobenthos Meeting 2, Gold Coast, Australia, 25-30/07/06.

8  - Lallier-Verges, E., Marchand, C., Albéric, P. and Disnar, J.-R. (2005). The fate of organic matter in mangrove sediments under variable redox conditions (French Guiana). 22ème International Meeting of Organic Geochemistry (IMOG), Séville, Espagne, 12-16/09/05.

7  - Marchand, C., Baltzer, F., Lallier-Verges, E., Albéric, P. and Cossa, D. (2004). Distribution des métaux lourds dans les sédiments de mangrove de Guyane française – Influence de la dynamique sédimentaire – Influence de la matière organique -. Ecosystème côtier amazonien (ECOLAB), Cayenne, Guyane française, 30/11-05/12/2004.

6  - Marchand, C., Lallier-Vergès, E., Baltzer F. and Albéric, P. (2004). Variabilités spatiales et saisonnières des paramètres physico-chimiques des sédiments de mangrove de Guyane française – Influence du développement de la végétation. Ecosystème côtier amazonien (ECOLAB), Cayenne, Guyane française, 30/11-05/12/2004.

5  - Debenay, J.P., Jouanneau, J.M., Sylvestre, F., Marchand, C., Lallier-Vergès, E. and Guiral, D. (2004). Microbenthos, its interrelation with sediments and organic matter.  Ecosystème côtier amazonien (ECOLAB), Cayenne, Guyane française, 30/11-05/12/2004.

4  - Marchand, C., Albéric, P., Baltzer, F. and Lallier-Vergès, E. (2003). Processes of organic accumulation in sediment and pore water along the mangrove fringed coast of French Guiana.. Society of Wetland Scientists (SWS), New-Orleans, LA, USA, 8-13/06/2003.

3  - Lallier-Vergès, E., Marchand, C., Baltzer, F. and Albéric, P. (2003). Reciprocal effect between mangrove species and sediment biogeochemistry in French Guiana. Society of Wetland Scientists (SWS), New-Orleans, LA, USA, 8-13/06/2003.

2  - Marchand, C., Baltzer, F. and Lallier-Verges, E. (2001). Biogeochemistry of mangrove sediment as witness of the evolution of a highly dynamic mangrove-fringed coast in French Guiana. 2001. Geochemistry in the Tropics (GEOTROP), Townsville, Australia 7-11/05/2001.

1  - Marchand, C., Lallier-Vergès, E. and Baltzer F. (2001). Organic markers as witnesses of the dynamic features of the mangrove coast in French Guyana. 2001. European Union of Geosciences (EUG), Strasbourg, France 8-12/04/2001.

 

Reviewer for the following scientific journals (in alphabetical order):

 

12- Bulletin of the Chemical Society of Ethiopia,

11- Chemical Geology,

10- Chemistry and Ecology,

9  - Deep Sea Research part II,

8  - Estuarine Costal and Shelf Science, 

7  - Geoderma,

6  - Journal of Oceanography,

5  - Marine Geology,

4  - Marine Pollution Bulletin,

 3 - Organic Geochemistry,

2  - Soil Science Society of America Journal,

1  - Wetlands Ecology and Management.


Home - Research Unit "Camelia" - Research Team - News - IRD Noumea