Spatial and Temporal Variability of Water Temperature during early Stage of Kelp Culture in Sanggou Bay, China

Abstract

The spatial-temporal variability of water temperature in autumn during the early stage of kelp culture in Sanggou Bay was studied based on moored measurements. The vertical profiles of temperature demonstrated that the water columns were well mixed. By using moving average filter, water temperature variations were decomposed to the trend (>12d), synoptic-scale (5~12d) component, and tidal-scale (<25h) component. Temperature variations were dominated by the trend which dropped gradually during the observation. The temperature decline rates, which were affected by water depth, varied from 0.16 °C/d to 0.24 °C/d. Synoptic and tidal cycles contributed to the temporal oscillations of temperature. The synoptic-scale components were also modulated by water depth. The ranges of tidal-scale component were higher at the bay mouth than those in the inner bay. Water temperature during the early stage of kelp culture was basically within the optimum ranges for kelp and bivalves.