Seagrass Water Temperature, Light Intensity and Sediment Phosphorus Mathematical Solutions for Estuary Management

The aim of this study was to apply Zostera capricorni growth rate mathematical solutions to saline coastal lagoons to generate novel mathematical insights that could be used by estuary managers in other estuaries and saline lagoons. It is proposed that the quadratic curvilinear 2nd Order relationships of seagrass growth rates with water temperature and subsurface light intensity, and with linear relationships for sediment total phosphorus, have the potential to inform catchment runoff management strategies by applying the equations to similar data obtained for other Zostera species in coastal lagoons and estuaries. The equation for water temperature includes an expected 1.4°C increase due to climate change in the seagrass beds, which was consistent with the derived water temperature equation. Thus, the detailed data and information obtained from the online and published studies of Zostera provided important biological processes for assessing the likely effects of the three main environmental drivers on seagrass growth rates. Analysis of the data determined the optimum temperature, light intensity thresholds before photo-inhibition, and a benchmark for sediment total phosphorus (TP) associated with growth rates and higher and more stable biomass in the urbanized areas of the studied lagoon system. The relationship between Zostera biomass and TP indicates the possible optimization of seagrass biomass by catchment nutrient runoff.