Statistical modelling of suspended sediment off Stonehaven

McCaig, Chris (2013) Statistical modelling of suspended sediment off Stonehaven. In: Marine Alliance for Science and Technology for Scotland: Annual Science Meeting, 2013-08-27 - 2013-08-29.

[thumbnail of Statistical modelling of suspended sediment off Stonehaven] Other. Filename: ChrisMcCaig.ppsx

Download (1MB)


Changes in suspended sediment concentration (SSC) are important for both the physical and ecological environment. One of the main impacts is on the attenuation of light intensity with depth, which affects phytoplankton and macrophyte primary production, and the environment for visual predators. However, detailed data on SSC are relatively scarce, so both dynamic and statistical models which may predict SSC from more readily available data are potentially valuable. We analysed a dataset of >400 turbidity profiles collected at weekly intervals during 2007-2011 at the Marine Scotland Science sampling site off Stonehaven on the east of Scotland. We sought to establish a statistical General Additive Model (GAM) of SSC at a given altitude above the seabed with explanatory variables being seabed depth, tidal, wind, wave, and river outflow data. Alternative models were assessed with Akaike's Information Criterion to choose between the fits offered by different models. Our final model provided a highly significant fit to the observed data from the main sampling site. We then tested the model by applying it to independent data collected at secondary sampling sites in both shallower and deeper water in the vicinity and showed that the model provided as significant account of the SSC dynamics at these site also.