학술논문

Intra‐colony spatial variance of oxyregulation and hypoxic thresholds for key Acropora coral species
Document Type
article
Source
Ecology and Evolution, Vol 14, Iss 3, Pp n/a-n/a (2024)
Subject
Coral oxyregulator
Coral reefs
Climate change
Hypoxic tolerance
Hypoxia Response Curves
Ocean deoxygenation
Ecology
QH540-549.5
Language
English
ISSN
2045-7758
Abstract
Abstract Oxygen (O2) availability is essential for healthy coral reef functioning, yet how continued loss of dissolved O2 via ocean deoxygenation impacts performance of reef building corals remains unclear. Here, we examine how intra‐colony spatial geometry of important Great Barrier Reef (GBR) coral species Acropora may influence variation in hypoxic thresholds for upregulation, to better understand capacity to tolerate future reductions in O2 availability. We first evaluate the application of more streamlined models used to parameterise Hypoxia Response Curve data, models that have been used historically to identify variable oxyregulatory capacity. Using closed‐system respirometry to analyse O2 drawdown rate, we show that a two‐parameter model returns similar outputs as previous 12th‐order models for descriptive statistics such as the average oxyregulation capacity (Tpos) and the ambient O2 level at which the coral exerts maximum regulation effort (Pcmax), for diverse Acropora species. Following an experiment to evaluate whether stress induced by coral fragmentation for respirometry affected O2 drawdown rate, we subsequently identify differences in hypoxic response for the interior and exterior colony locations for the species Acropora abrotanoides, Acropora cf. microphthalma and Acropora elseyi. Average regulation capacity across species was greater (0.78–1.03 ± SE 0.08) at the colony interior compared with exterior (0.60–0.85 ± SE 0.08). Moreover, Pcmax occurred at relatively low pO2 of