Rising CO₂ enhances hypoxia tolerance in a marine fish.

ABSTRACT: Global environmental change is increasing hypoxia in aquatic ecosystems. During hypoxic events, bacterial respiration causes an increase in carbon dioxide (CO₂) while oxygen (O₂) declines. This is rarely accounted for when assessing hypoxia tolerances of aquatic organisms. We investigated the impact of environmentally realistic increases in CO₂ on responses to hypoxia in European sea bass (Dicentrarchus labrax). We conducted a critical oxygen (O_2crit) test, a common measure of hypoxia tolerance, using two treatments in which O₂ levels were reduced with constant ambient CO₂ levels (~530 µatm), or with reciprocal increases in CO₂ (rising to ~2,500 µatm). We also assessed blood acid-base chemistry and haemoglobin-O

SUBMITTER: Montgomery DW 

PROVIDER: S-EPMC6805886 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature