Acid-base balance and changes in haemolymph properties of the South African rock lobsters, Jasus lalandii, a palinurid decapod, during chronic hypercapnia

• Main Authors: Knapp, Jarred L, Bridges, Christopher R, Krohn, Janina, Hoffman, Louwrens C, Auerswald, Lutz
• Format: Dataset
• Language: English
• Published: PANGAEA 2015
• Subjects: Acid-base regulation; Alkalinity; total; standard error; Animalia; Aragonite saturation state; Arthropoda; Benthic animals; Benthos; Bicarbonate; Bicarbonate ion; BIOACID; Biological Impacts of Ocean Acidification; Bohr Coefficient; Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Coast and continental shelf; Containers and aquaria (20-1000 L or < 1 m**2); Figure; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Haemolymph; calcium ion; haemocyanin; lactate; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.847479; https://doi.org/10.1594/PANGAEA.847479

Few studies exist reporting on long-term exposure of crustaceans to hypercapnia. We exposed juvenile South African rock lobsters, Jasus lalandii, to hypercapnic conditions of pH 7.3 for 28 weeks and subsequently analysed changes in the extracellular fluid (haemolymph). Results revealed, for the first time, adjustments in the haemolymph of a palinurid crustacean during chronic hypercapnic exposure: 1) acid-base balance was adjusted and sustained by increased bicarbonate and 2) quantity and oxygen binding properties of haemocyanin changed. Compared with lobsters kept under normocapnic conditions (pH 8.0), during prolonged hypercapnia, juvenile lobsters increased bicarbonate buffering of haemolymph. This is necessary to provide optimum pH conditions for oxygen binding of haemocyanin and functioning of respiration in the presence of a strong Bohr Effect. Furthermore, modification of the intrinsic structure of the haemocyanin molecule, and not the presence of molecular modulators, seems to improve oxygen affinity under conditions of elevated pCO2.