Accounting for the influence of temperature and location when predicting seagrass (Halophila ovalis) photosynthetic performance

We show that the effect of temperature on photosynthesis a widely distributed and ecological important seagrass species was not consistent among locations, with some evidence acclimation to local range. This has implications for modelling productivity impacts light reduction ecosystems. Reduced availability is one main pressures negatively impacting meadows worldwide. Our knowledge photosynthetic characteristics critical predicting managing reducing activities but suffers from two information gaps: first, data overwhelmingly derived studies leaf tissue whole plants, unlikely reflect plant performance under stress; second, few have looked at spatial temporal variability in seagrasses. investigated variation range temperatures plants Halophila ovalis, species, by measuring oxygen exchange intact collected four locations across latitudinal gradient (10°) three (17 °C, 23 28 °C). For all affected parameters, parameters (NPmax, R, Ik) showing distinct difference between tropical temperate locations. example, NPmax ranged 1.35 ± 0.12 5 0.16 mg O₂. g DW−1. hr−1 4 0.3 12 0.68 location. However, often rate greatest approaching mean month maximum location, suggestive acclimation. Time year also rates how influenced those rates. conclude application P–I model, predict or manage H. likely other may require site- time-specific relationships.