This dataset comprises physiological and metabolic measurements of the southern king crab, Lithodes santolla, exposed to different temperatures (0–25 ºC) and two oxygen conditions (Normoxia: 21 kPa and Reduction: 12 kPa). Physiological variables include oxygen consumption, heart rate, and ventilation rate. The dataset was generated to evaluate the physiological responses of L. santolla to environmental variation in temperature and oxygen availability. Physiological data were collected in 2016 at the Alfred Wegener Institute, List/Sylt, Germany, using animals transported from Punta Arenas, Chile, during the PS98 expedition (10 April to 11 May 2016). Oxygen concentration was measured using optical oxygen sensors (PSt3, PreSens GmbH, Germany). Heart and ventilation rates were recorded by infrared photoplethysmography (photoplethysmographs and amplifiers from iSiTEC GmbH, Germany) and digitized using a PowerLab acquisition system (ADInstruments, United Kingdom).
Temperature is a major driver for the geographical distribution of organisms, such as the foundation kelp species Saccharina latissima. Globally rising sea surface temperatures and intensification of marine heatwaves have already led to local loss of kelp populations. We investigated temporal variations in the thermal susceptibility of S. latissima. Therefore, we assessed the stress responses of field sporophytes sampled from Helgoland (German Bight) to an experimental heat wave scenario in June 2018, August 2018, and August 2019. The experiment in June 2018 was conducted by Diehl et al. (2021a) and the respective dataset (Diehl et al. 2021b, https://doi.org/10.1594/PANGAEA.931637) was re-evaluated for this study. Treatment temperatures (18, 20, 22, 24 °C) were based on 18 °C summer mean sea surface temperature on Helgoland as control, and Δ+2, Δ+4, Δ+6 °C as temperature-amplitude treatments, mimicking marine heatwaves. After a three-days wound healing phase, seven days of temperature acclimation (day 0-7) and seven days of temperature treatment (day 8-14) followed. The survival, growth and maximum photosynthetic quantum yield (Fv/Fm; June 2018/August 2018: ImagingPAM, Walz Imaging PAM Maxi Version M-series; August 2019: Portable Chlorophyll Fluorometer PAM-2100, Heinz Walz GmbH, Effeltrich, Germany) were measured on day 0 and day 14. To highlight changes as response to the experimental heat wave, physiological parameters were shown as percentage of the initial values. Absolute concentrations of pigments were analyzed using a HPLC. Afterwards, accessory pigment (Acc) and xanthophyll cycle pigment (VAZ) concentration, as well as the de-epoxidation state of the xanthophyll cycle (DPS) and ratios were calculated.