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Limited climatic niche filling o f mangroves
Q uisthoudt Katrien12, Loïc Pellissier3, Farid D ahdouh-G uebas'2, Nico Koedam2
and C hristophe F. Randin4
1 Laboratory o f Systems Ecology and Resource Management, Université Libre de Bruxelles
Av. F. D. Roosevelt, 50, B-1050, Brussels, Belgium
e-mail: kauistho@ ulb.ac.be
2 Laboratory o f Plant Biology and Nature Management, Vrije U niversiteit Brussel
Pleinlaan, 2, B-1050 Brussels, Belgium
3 A rctic Research Centre, D epartm ent o f Bioscience, Aarhus University, Aarhus, Denmark
4 Institute o f Botany, U niversität Basel, Schönbeinstrasse 6, 4056 Basel, Switzerland
An expansion o f the d istrib u tio n o f mangroves tow ards higher latitudes m ig ht be expected as a
consequence o f global w arm ing. However, mangroves may not yet have reached an e q u ilib riu m w ith
the current clim ate because o f Quaternary clim ate oscillations. This lack o f e q u ilib riu m may lim it
the a b ility to forecast mangrove range dynamics. In th is study, we exam ined the d is trib u tio n o f
mangroves w orldw ide to determ ine w hether and where mangrove species have reached the
potential latitud in al lim its dictated by clim ate.
We predicted the current d istrib u tio n o f the w o rld ’s 39 d om in a nt m angrove tree species based on
an ensemble o f species d istrib u tio n models (SDMs). The projected and observed latitud in al lim its o f
the mangrove fo re st and o f each species were com pared to id e n tify p otential areas w ith lim ited
clim atic niche fillin g (i.e. geographic areas where m angrove species are absent despite the
occurrence o f a p ote ntia lly suitable climate according to the SDMs).
Most mangrove species are not com pletely in e q u ilib riu m w ith cu rren t clim ate conditions. However,
where there is a continuous coastline fro m the southern to the northern latitud in al lim it (e.g. EastAfrica) more species have reached th e ir potential clim atic latitud in al lim its com pared to regions that
are composed o f scattered islands (e.g. South-East Asia). Hence, the greater prevalence o f lim ited
clim atic niche fillin g in the latter may be a ttrib u te d to dispersal tim e lag and the changes in the
config uratio n o f islands
Our study indicates a discrepancy between clim ate s u ita b ility and the accessibility o f sites by
mangrove species during colonisation. This fin d in g also suggests th a t lim ited m igrations by
mangrove species w ill occur in certain regions in a fu tu re w arm ing clim ate.
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