10 research outputs found
International Nonregimes: A Research Agenda1
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146934/1/j.1468-2486.2007.00672.x.pd
Coral adaptation in the face of climate change: Response
[Extract] In their Review, "Coral reefs under rapid climate change and ocean acidification" (14 December 2007, p. 1737), O. Hoegh-Guldberg et al. present future reef scenarios that range from coral-dominated communities to rapidly eroding rubble banks. Notably, none of their scenarios considers the capacity for corals to adapt. The authors dismiss adaptation because "[r]eef-building corals have relatively long generation times and low genetic diversity, making for slow rates of adaptation [relative to rates of change]." We think the possibility of adaptation deserves a second look.\ud
\ud
Many features of coral life histories, such as extended life spans, delayed maturation, and colony fission, do result in long generation times (1) [some between 33 and 37 years (2)]. However, other corals, such as many species of Acropora and Pocillopora, mature early, grow rapidly, and suffer whole-colony mortality, as opposed to colony fission, after mechanical disturbances (3) and thermal stress (4). The life histories of these ecologically important and abundant species suggest an underappreciated capacity to adapt rapidly to changing environments
Coral reefs under rapid climate change and ocean acidification
Atmospheric carbon dioxide concentration is expected to exceed 500 parts per million and global temperatures to rise by at least 2 degrees C by 2050 to 2100, values that significantly exceed those of at least the past 420,000 years during which most extant marine organisms evolved. Under conditions expected in the 21st century, global warming and ocean acidification will compromise carbonate accretion, with corals becoming increasingly rare on reef systems. The result will be less diverse reef communities and carbonate reef structures that fail to be maintained. Climate change also exacerbates local stresses from declining water quality and overexploitation of key species, driving reefs increasingly toward the tipping point for functional collapse. This review presents future scenarios for coral reefs that predict increasingly serious consequences for reef- associated fisheries, tourism, coastal protection, and people. As the International Year of the Reef 2008 begins, scaled- up management intervention and decisive action on global emissions are required if the loss of coral- dominated ecosystems is to be avoided