Investigation of the influence of modified sediment on pH using rapid pH assessment methods

Abstract

Ocean acidification is changing the chemistry of the ocean and has the potential to result in large-scale ecosystem changes. Observations of dissolved shells and low survivorship rates of juvenile bivalves are a concern for the aquaculture industry. This research conducted in Baynes Sound, assessed the variability of sediment pH measurements between farmed and non-farmed beaches; evaluated the use of an Orion low maintenance pH triode and a Honeywell Durafet to rapidly assess sediment pH; examined existing shell content between farmed and non-farmed beaches; determined if there is a relationship between shell content and sediment pH; and determined if there is a difference in sediment pH and/or shell content in spatially separate sites. Sediment pH was highly variable, both between and within sites and no buffering effect was observed from existing shell content in the sediment. Any influences of aquaculture practices and shell content were prevailed by regional differences.