Acidification mitigation plan for high priority salmon watersheds: effectiveness of liming to reduce toxic aluminum levels

Ionic aluminium (Ali) is toxic to Salmo salar and is known to be a key cause of population declines. Increases in Ali are caused by acidification. Aluminium levels are currently increasing in NS rivers. The results of the 2014-17 ASCF Dalhousie Ali survey (Sterling et al., 2018) show that all rivers tested have toxic levels of Ali. Without mitigation treatment, current trends indicate Ali levels will worsen, posing increased threats for salmon. This project will be using the 2014-2017 Ali survey information generated from our previous ASCF grant to determine how best to address the problem, using liming. This project will sample Ali levels in control and treatment catchments of Dr. Sterling’s current liming initiatives in NS. This information will be used to determine which liming method is best for reducing Ali levels, such as which is the best mineral composition and dose for liming.

Contact: Dr. Shannon Sterling, 902 494 3431, shannonsterling@dal.ca