Activities have the potential to increase or decrease local salinity through either input of fresh water or physical changes that may alter water exchange and therefore salinity. Changes to salinity can impact growth, respiration, behaviour, and reproduction, and may ultimately alter communities/habitats, particularly if combination with other stresses such as temperature.
Benchmark:
Increase from 35 to 38 units for one year or Decrease in salinity by 4-10 units for a year.
Examples:
Discharges from pipelines, capital dredging if this alters the halocline/tidal exchange, erection of barrages, weirs that alter freshwater and seawater flow or exchange rates.
Notes:
Excludes fin fish fresh water treatment for sealice as not at benchmark (altering salinity for a year). Excludes carbon storage as salt cavern washings not relevant to Scotland.