Risk Assessment of Gypsum Amendment on Agricultural Fields: Effects of Sulfate on Riverine Biota.

Gypsum (CaSO ∙2H O) amendment is a promising way of decreasing the phosphorus loading of arable lands, and thus preventing aquatic eutrophication. However, in freshwaters with low sulfate concentrations, gypsum-released sulfate may pose a threat to the biota. To assess such risks, we performed a series of sulfate toxicity tests in the laboratory and conducted field surveys.

Assessment of Fish Embryo Survival and Growth by In Situ Incubation in Acidic Boreal Streams Undergoing Biomining Effluents.

The applicability of an in situ incubation method in monitoring the effects of metal mining on early life stages of fish was evaluated by investigating the impacts of a biomining technology utilizing mine on the mortality, growth, and yolk consumption of brown trout (Salmo trutta) and whitefish (Coregonus lavaretus) embryos. Newly fertilized eggs were incubated from autumn 2014 to spring 2015 in six streams under the influence of the mine located in North-Eastern Finland and in six reference streams. Although the impacted streams clearly had elevated concentrations of several metals and sulfate, the embryonic mortality of the two species did not differ between the impacted and the reference streams.