title: Species-specific responses to climate change and community composition determine future calcification rates of Florida Keys reefs.
abstract: Anthropogenic climate change compromises reef growth as a result of increasing temperatures and ocean acidification. Scleractinian corals vary in their sensitivity to these variables, suggesting species composition will influence how reef communities respond to future climate change. Because data are lacking for many species, most studies that model future reef growth rely on uniform scleractinian calcification sensitivities to temperature and ocean acidification. To address this knowledge gap, calcification of twelve common and understudied Caribbean coral species was measured for two months under crossed temperatures (27, 30.3 °C) and CO2partial pressures (pCO2) (400, 900, 1300 μatm). Mixed-effects models of calcification for each species were then used to project community-level scleractinian calcification using Florida Keys reef composition data and IPCC AR5 ensemble climate model data. Three of the four most abundant species, Orbicella faveolata, Montastraea cavernosa, and Porites astreoides, had negative calcification responses to both elevated temperature and pCO2. In the business-as-usual CO2emissions scenario, reefs with high abundances of these species had projected end-of-century declines in scleractinian calcification of >50% relative to present-day rates. Siderastrea siderea, the other most common species, was insensitive to both temperature and pCO2within the levels tested here. Reefs dominated by this species had the most stable end-of-century growth. Under more optimistic scenarios of reduced CO2emissions, calcification rates throughout the Florida Keys declined <20% by 2100. Under the most extreme emissions scenario, projected declines were highly variable among reefs, ranging 10-100%. Without considering bleaching, reef growth will likely decline on most reefs, especially where resistant species like S. siderea are not already dominant. This study demonstrates how species composition influences reef community responses to climate change and how reduced CO2emissions can limit future declines in reef calcification.
authors: Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA.|Joint Institute for the Study of the Atmosphere and Ocean, University of Washington, 3737 Brooklyn Ave NE, Seattle, WA, 98195, USA.|NOAA Pacific Marine Environmental Laboratory, 7600 Sandpoint Way NE, Seattle, WA, 98115, USA.
authors: Remy R
authors: RR
authors: Okazaki
authors: Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA.
authors: Erica K
authors: EK
authors: Towle
authors: Ocean Chemistry and Ecosystems Division, NOAA Atlantic Oceanographic and Meteorological Laboratory, 4301 Rickenbacker Cswy, Miami, FL, 33149, USA.|Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA.
authors: Ruben
authors: 0000-0002-3804-1233
authors: R
authors: van Hooidonk
authors: Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA.
authors: Carolina
authors: C
authors: Mor
authors: Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA.
authors: Rivah N
authors: RN
authors: Winter
authors: Department of Marine Geosciences, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA.
authors: Alan M
authors: AM
authors: Piggot
authors: Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA.
authors: Ross
authors: R
authors: Cunning
authors: Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA.
authors: Andrew C
authors: AC
authors: Baker
authors: Department of Geological Sciences, University of Miami, 1320 S. Dixie Hwy, Coral Gables, FL, 33124, USA.
authors: James S
authors: JS
authors: Klaus
authors: Department of Marine Geosciences, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA.
authors: Peter K
authors: PK
authors: Swart
authors: Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA.
authors: Chris
authors: C
authors: Langdon
mesh_terms: D000818:Animals; D037421:Anthozoa; D017691:Caribbean Region; D057231:Climate Change; D057894:Coral Reefs; D005431:Florida; D011157:Population Dynamics; D012623:Seawater
keywords: Florida Reef Tract; biomineralization; calcification; climate change; coral reefs; dissolution; ocean acidification; precipitation; scleractinia; warming