Sie können Bookmarks mittels Listen verwalten, loggen Sie sich dafür bitte in Ihr SLUB Benutzerkonto ein.
Medientyp:
E-Artikel
Titel:
Multi-decadal changes in structural complexity following mass coral mortality on a Caribbean reef
Beteiligte:
Roff, George;
Joseph, Jennifer;
Mumby, Peter J.
Erschienen:
Copernicus GmbH, 2020
Erschienen in:Biogeosciences
Sprache:
Englisch
DOI:
10.5194/bg-17-5909-2020
ISSN:
1726-4189
Entstehung:
Anmerkungen:
Beschreibung:
<jats:p>Abstract. In recent decades, extensive mortality of reef-building corals
throughout the Caribbean region has led to the erosion of reef frameworks and
declines in biodiversity. Using field observations, structural models, and
high-precision U–Th dating methods, we quantify changes in structural
complexity in the major framework-building coral Orbicella annularis over a 20-year period at
Long Caye (Belize). Despite extensive mortality following the mass coral
bleaching event of 1998, the structural complexity of frameworks remained
largely unchanged between 1998 (rugosity index, R, of 2.35±0.1) and
2018 (R of 2.29±0.1). Colony-scale structural complexity was maintained,
as the rapid growth of surviving ramets (0.69±0.1 cm yr−1)
offset the slower bioerosion of dead ramets (-0.11±0.16 cm yr−1). Despite the apparent stability of the structural complexity at
colony scales, bioerosion of individual dead ramets over 2 decades led to
declines in microhabitat complexity, with an overall reduction in the depth
of microhabitats within frameworks. Altered microhabitat complexity appears
to have negative effects on cryptic fauna, with the grazing urchin
Echinometra viridis declining from 1.5±0.4 individuals m−2 in 1998 to 0.02± individuals m−2 in 2018. Changes in microhabitat complexity have the potential to
alter ecological interactions that can impact recovery dynamics on coral
reefs in ways that are undetectable using traditional rugosity metrics of
structural complexity.
</jats:p>