Low calcification rates and calcium carbonate production in Porites panamensis at its northernmost geographic distribution

Abstract

Porites panamensis is a hermatypic coral present in the eastern Pacific Ocean. Skeletal growth parameters have been reported, but studies of the relationship between annual calcification rates and environmental controls are scarce. In this study, we investigated three aspects of the annual calcification rates of P. panamensis: growth parameters among three P. panamensis populations; the sea surface temperature as a calcification rate control spanning a latitudinal gradient; and calcium carbonate production among three sites. Growth parameters varied among the sites due to the colony growth form. Massive colonies in the north showed a higher calcification rate than encrusting colonies in the south (mean: 1.22-0.49 g CaCO 3 Á cm À2 Á yr À1 ), where variations in calcification rates were related to growth rate (0.91-0.38 cm Á yr À1 ) rather than to skeletal density differences (overall mean AE SD, 1.31 AE 0.04 g CaCO 3 Á cm À3 ). Our results showed a positive linear relationship between annual calcification rates and sea surface temperatures within these P. panamensis populations. Differences were related to distinct oceanographic environments (within and at the entrance of the Gulf of California) with different sea surface temperature regimes and other chemical properties. Different populations calcified under different environmental conditions. Calcium carbonate production was dependent upon the calcification rate and coral cover and so carbonate production was higher in the north (coral cover 12%) than in the south (coral cover 3.5). Thus, the studied sites showed low calcium carbonate production (0.25-0.43 kg CaCO 3 Á m À2 Á yr À1 ). Our results showed reduced calcification rates, regional temperature regime control over calcification rates, different growth forms, low coral cover and low calcium carbonate production rates in P. panamensis.Marine Ecology (2014) 1-12 ª

Environmental and physiochemical controls on coral calcification along a latitudinal temperature gradient in Western Australia

“…Our results further show that curve‐shaped seasonal temperature growth responses due to localized acclimation (e.g., for Galaxea spp. and Acropora dowingi ; Marshall & Clode, ; Vajed Samiei et al, ) and the positive relationship between temperature and calcification rates along tropical temperature gradients (e.g., for Montastraea and Porites ; Carricart‐Ganivet, ; Lough & Barnes, ; Lough et al, ; Norzagaray‐López et al, ) may be species‐ and location‐specific and not generally applicable to all coral genera, particularly those whose range extends to subtropical environments.…”

Differences in Growth and Calcification Rates in the Reef-Building Coral Porites lobata: The Implications of Morphotype and Gender on Coral Growth

“…Despite the importance of morphologic and growth variability in the reef structure, limited studies have been performed on massive corals (Graus and MacIntyre, 1982;Tomascik, 1990;Van Veghel and Bosscher, 1995;Smith et al, 2007). These include the reported by Norzagaray-López et al (2014) who found growth differences between columnar and encrusting colonies, nevertheless it is important to highlight that these differences were possibly biased by the effect of the gender and latitudinal gradients variations. To date, a comparison of the growth of different morphotypes including the gender effect in Poritid corals has not been undertaken, though it seems reasonable to speculate that columnar, massive and free-living forms may calcify at different rates in each specific gender.…”

Upwellings mitigated Plio-Pleistocene heat stress for reef corals on the Florida platform (USA)

“…More recent studies have shown the systematics of calcification to differ among taxa and ocean regions. While temperature tends to boost calcification rates in recent z corals, temperature effects on extension rate and density markedly differ (Carricart-Ganivet, 2004;Elizalde-Rendon et al, 2010;Lough, 2008;Norzagary-Lopez et al, 2014). In the IndoPacific genus Porites, linear extension rate shows a significant increase with sea-water temperature but a concomitant decrease in bulk skeletal density (Lough, 2008).…”

“…Upon microscopic investigation using SEM ( Fig. 2a-g), the skeletons display stacked spherulites or fans and layers of fibrous aragonite which represent the microstructures typical of scleractinian corals (Constantz, 1986;Nothdurft and Webb, 2007). Within the centres of the single calcifying units (sclerodermites), porosity is more or less enhanced and the aragonite crystallites are particularly small, granular in shape and have no preferential orientation (Fig.…”

“…Near-surface, open, straight tubular cavity systems, commonly Y-branched, with diameters < 5 µm and parallel to skeletal surfaces ( Fig. 2d) are less than 1 % by volume and probably caused by endolithic fungi (Nothdurft and Webb, 2007).…”