TY - JOUR T1 - Elevated maximum temperatures and high-magnitude thermal variability drive low coral diversity on nearshore lagoonal reefs on the Belize JF - bioRxiv DO - 10.1101/036400 SP - 036400 AU - JH Baumann AU - JE Townsend AU - TA Courtney AU - HE Aichelman AU - SW Davies AU - FP Lima AU - KD Castillo Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/01/14/036400.abstract N2 - Aim Coral reefs are increasingly threatened by interactions of global and local anthropogenic stressors, two of the most prominent being rising seawater temperature and nutrient enrichment. We aim to determine how spatiotemporal variations of environmental stressors across a reefscape determine which coral species are most successful during this climate change interval.Location Belize, Central AmericaMethods Thirteen lagoonal reefs on the Belize Barrier Reef System (BBRS) were surveyed to investigate the influence of temperature and nutrient history on coral community structure across reefscapes. A novel metric was developed using ultra-high resolution sea surface temperature (SST) records to classify reefs as enduring low temperature parameters (lowTP), moderate temperature parameters (modTP), or extreme temperature parameters (extTP) based on four thermal parameters known to be important drivers of overall reef healthResults Coral species richness, abundance, diversity, density, and percent cover were lower at extTP sites compared to lowTP and modTP sites, but these reef community traits did not differ between lowTP and modTP sites. Coral life history strategy analyses indicated that extTP sites were dominated by hardy stress-tolerant and fast growing weedy coral species, while lowTP and modTP sites included competitive, generalist, weedy, and stress-tolerant coral species.Main Conclusions Coral community differences between extTP and lowTP/modTP sites were primarily driven by temperature differences. While the influence of nutrients on reef community traits was minimal, bulk nutrient concentrations likely affected percent coral cover. Lack of community scale differences between lowTP and modTP sites is likely driven by low-magnitude thermal variations in these reef locations. Dominance of weedy and stress-tolerant genera at extTP sites suggests that corals utilizing these two life history strategies may be better suited to cope with IPCC projected ocean warming conditions. Our results reveal that temperature is the primary driver of differences in coral community composition among these distinct reef environments. ER -