The effects of NaCl Deicing Salts on Sphagnum Recurvum P. Beauv

Abstract

In response to documented impacts of deicing salt runoff from a salt storage area along the Indiana Toll Road on the vegetation of Pinhook Bog, a student of the effect on NACl on one of the prominent bryophytes of the bog was initiated. Salt concentrations between 300 and 1500 mg/l as CL significantly reduced growth in length of Sphagnum recurvum in laboratory cultures. Growth in biomass was also reduced at higher concentrations under certain treatment conditions. Chloride appeared to be a greater growth inhibitor than chloride. In experiments in which water contact was reduced and evaporational plant surfaces increased, salt was deposited on plant tips through the evapotranspiration process, resulting in plant mortality at all NaCl concentrations tested. Washing of plant to simulate rainfall removed the salt encrustations, but they developed again quickly and produced similar lethal effects within 3 weeks of the last wash treatment. Since growth reduction and mortality of S. recurvum were shown at NaCl concentrations observed in Pinhook Bog, it is likely that deicing salts were responsible for the elimination of Sphagnum from the impacted area.