Is Ocean acidification really a threat to marine calcifiers?


Is Ocean acidification really a threat to marine calcifiers?

Is Ocean Acidification Really a Threat to Marine Calcifiers? A Systematic Review and Meta-Analysis of 980+ Studies Spanning Two Decades, is a study published on the Small - Weinheim an der Bergstrasse, which makes an interesting retrospective on an aspect that unfortunately is becoming increasingly popular in the oceans, and is a direct consequence of the climate crisis.

It has been estimated that between 1751 and 1994, the surface pH of ocean waters decreased from 8.25 to 8.14, with a corresponding increase in the concentration of H + ions, equal to 26% The process of continuous acidification of oceanic waters undoubtedly leads to effects on the food chain and, in particular, can affect the lysocline and the compensation depth of the carbonates; resulting in the dissolution of the calcareous shells of shells, molluscs and calcareous plankton, consisting of calcium carbonate (CaCO3).

Researches explained: "Ocean acidification is considered detrimental to marine calcifiers, but mounting contradictory evidence suggests a need to revisit this concept. This systematic review and meta-analysis aim to critically re-evaluate the prevailing paradigm of negative effects of ocean acidification on calcifiers." They then added: "Based on 5153 observations from 985 studies, many calcifiers (e.g., echinoderms, crustaceans, and cephalopods) are found to be tolerant to near-future ocean acidification (pH ≈ 7.8 by the year 2100), but coccolithophores, calcifying algae, and corals appear to be sensitive.

Calcifiers are generally more sensitive at the larval stage than adult stage."

Is Ocean acidification really a threat to marine calcifiers?

Researchers also said: "Over 70% of the observations in growth and calcification are non-negative, implying the acclimation capacity of many calcifiers to ocean acidification.

This capacity can be mediated by phenotypic plasticity (e.g., physiological, mineralogical, structural, and molecular adjustments), transgenerational plasticity, increased food availability, or species interactions. The results suggest that the impacts of ocean acidification on calcifiers are less deleterious than initially thought as their adaptability has been underestimated.

Therefore, in the forthcoming era of ocean acidification research, it is advocated that studying how marine organisms persist is as important as studying how they perish, and that future hypotheses and experimental designs are not constrained within the paradigm of negative effects."