Sentences with phrase «calcification rates»
"Calcification rates" refer to the speed or rate at which a substance or tissue in the body becomes hardened or forms calcium deposits. Full definition
In addition, they state that there was «no significant correlation between calcification rate and seawater aragonite saturation (Ωarag)» and «no evidence of CO2 impact on bleaching.»
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Ocean acidification may increase calcification rates, but at a cost.
* The rising CO2 content of the atmosphere may induce very small changes in the well - buffered ocean chemistry (pH) that could slightly reduce coral calcification rates; but potential positive effects of hydrospheric CO2 enrichment may more than compensate for this modest negative phenomenon.
These responses include impacts on calcification rates [18,19], immune function [20], reproduction and carryover effects in larval and juvenile stages of invertebrates [21], enhanced productivity in phytobenthos [22 — 25] but reduced calcification and growth in calcareous algae [26 — 28].
Dr Sarah O'Dea, from Ocean and Earth Science at the University of Southampton and lead author of the study, says: «Our results show that climate change significantly altered coccolithophore calcification rates at the PETM and has the potential to be just as significant, perhaps even more so, today.
Not all species will react the same: In 2008, studies showed that ocean acidification may even boost calcification rates in some animals.
He has also published in the scientific literature detailing his concerns about the methodology used to measure calcification rates, including a technical paper in Marine Geology (volume 65).
Lower calcification rates would reduce the alkalinity pump, reduce surface CO2 and increase the buffering capacity of surface waters.
It is the rate of photosynthesis and the energy it provides that typically controls calcification rates.
Percentage change in calcification rates plotted against seawater aragonite saturation state
TA, total alkalinity; DIC, dissolved inorganic carbon; pCO2, carbon dioxide concentration; HCO3 −, bicarbonate concentration; CO32 −, carbonate concentration; POC, particulate organic carbon content per cell; PP, primary production per cell; PIC, particulate inorganic carbon content per cell; CR, calcification rate per cell; Chl a, chlorophyll a content per cell.
Our novel technique involved analysing coccolithophore skeletal remains and applying observations from modern specimens to estimate, for the first time, calcification rates of fossil coccolithophores.»
Extension rates are presented here (Figure 2), as changes in calcification rates are mainly driven by extension due to minimal density fluctuations in these cores (Figure S1, S2); this has been found in other studies as well [11], [42].
They found that calcification rates under these manipulated pre-industrial conditions were higher than they are today.
When exposed to ocean acidification in controlled laboratory experiments, growth and calcification rates of the single - celled alga are slightly reduced.
It found that calcification rates of C. pelagicus and T. pertusus halved during the PETM, due to changes in environmental factors that influenced their growth.
For statistical analyses, one - way ANOVA was used and followed by Tukey HSD (honestly significant differences) to assess the differences in experimental treatments of calcification rates and genes» real - time PCR results.
The coral fragments that have been subjected to SW + 200, were removed from gene expression analysis because no statistically significant was found between the calcification rates of SW + 100 and SW + 200 treatments (Fig. 2).
When treated by seawater with high calcium concentrations (addition of 100 gm / L, added as CaCl2.2 H2O), the coral increases its calcification rates and associated genes were up - regulated as a result, which were then identified.
Hence, it could be suggested that the small differences in the calcification rates observed between 100 mg / L and 200 mg / L calcium additions during the day could be a result of relatively mediocre photosynthetic activities of the endo - symbionts, but this should be further studied.
Laboratory studies have examined the effects of ocean acidification on many types of corals and coralline algae, revealing a range of responses from a 3 % to 60 % decline in calcification rate for a doubling of atmospheric CO2.ref A recent study of brain corals in Bermuda found that calcification rates have declined by 25 % over the past 50 years and ocean acidification is a likely contributing factor.
All coastal engineering communities support intense metabolic processes, including high primary production, respiration and calcification rates, thereby affecting CO2, CO3 −, and alkalinity concentrations and surface water pH. However, many metabolically intense coastal habitats are experiencing global declines in their abundance at rates in excess of 1 % per year (Duarte et al. 2008; Ermgassen et al. 2013).