The impact of nitrate pollution in waterways on freshwater species

Nitrate pollution in freshwater environments is caused by runoff from fertilisers, urban waste and debris. Despite evidence of the negative effects of nitrate on aquatic species, it is considered to be relatively non-toxic. Yet after heavy rain, it can found in concentrations up to 100 times the current safe guideline of 50 mg/l. We investigated how nitrate interacts with other environmental stressors (acidity, high temperatures and low oxygen) to impact freshwater fish and crustaceans through a series of tank and flume experiments on three common native species.