Abstract
Shallow marine macrophyte communities serve key roles in the tropical coastal ecosystem but are undergoing large and rapid deterioration worldwide, as is also the case in the non-estuarine mangrove lagoon of Lac Bay, Bonaire, in the Southern Caribbean. To help better understand both the drivers of assemblage structure and potential consequences of the changes taking place in the bay, we here quantify and describe the distribution of algal and seagrass assemblages along the environmental gradient from the turbid, inner mangrove pools to the clear, open bay conditions, based on 98 randomly-chosen, 4 m2 survey plots. Seven assemblages were described along this land-to-sea gradient, five of which were dominated by marine macrophytes, one by sponges and one by a polychaete. With exception of the hypersaline backwaters which were devoid of benthic macrophyte vegetation, isolated mangrove pools showed the lowest total benthic cover, species richness and biodiversity of all habitats. Salinity and substrate particle-size composition accounted for most variation between the different assemblages and appear to be the key known determinants of assemblage composition. We developed a conceptual model to help disentangle the relationship between and the relative roles of the two principal drivers, as part of a cascade of effects which ultimately result from terrestrial run-off into the bay as mediated by mangrove encroachment into the bay. The model links spatial patterns to ongoing processes and implies that the assemblage patterns described are not only a reflection of, but also allow prediction of how the assemblages develop through time.
Original language | English |
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Article number | 103148 |
Pages (from-to) | 1-16 |
Number of pages | 16 |
Journal | Aquatic Botany |
Volume | 159 |
Early online date | 29 Jul 2019 |
DOIs | |
Publication status | Published - Dec 2019 |
Funding
This work was conducted on Bonaire under auspices of Stinapa Bonaire and with critical support by Ramon de León, manager of the Bonaire Marine Park. Main funding was provided by the Netherlands Ministry of Agriculture, Nature and Food Quality under project number 4308701003 to A. Debrot, principal investigator, as part of the Wageningen University BO program (BO-11-011.05-007) and to Erik Meesters under program BO-11-011.05-012. Wageningen Marine Research provided supplemental funding through student internship grants to A. Hylkema and W. Vogelaar. We further thank Frank van Slobbe of DROB-Bonaire for arranging the necessary permits and the STINAPA rangers and additional staff, for their advice, cooperation and assistance. Liesbeth van der Vlies is thanked for help in preparing the manuscript for publication and Jessica Schop for drawing our model diagram and Callum Reid for finalizing our two maps. Dr. R. Peachey generously allowed us to use the CIEE Bonaire laboratory facilities while Dr. Maarten Prins and Martine Hagen kindly allowed us to use their sediment analysis laboratory at the Free University of Amsterdam. Finally we thank Ellard Hunting from the University of Amsterdam for identifying the unknown sponges and remain indebted to two anonymous reviewers for providing several critical reviews which allowed major improvements to our manuscript.
Funders | Funder number |
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Free University of Amsterdam | |
Netherlands Ministry of Agriculture, Nature and Food Quality | 4308701003 |
Universiteit van Amsterdam | |
Wageningen University and Research | BO-11-011.05-012, BO-11-011.05-007 |
Keywords
- Drivers of assemblage structure
- Mangrove land reclamation
- Non-estuarine mangrove system model
- Tropical seagrass