Effect of Deicing Salts on Urban Soils and the Health of Roadside Pines (<i>Pinus tabulaeformis</i>) in Northeast China

Abstract

Accumulation of high concentrations of Na and Cl ions in soils is one factor that hampers plant establishment along roadsides in regions where deicing salts are used to improve winter driving conditions. However, there is little information on the accumulation of deicing salts in roadside soil as well as on the phytotoxic impact of deicing salts on pines in Northeast China. The accumulation of salt in soil and injuries on pine needles (Pinus tabulaeformis) were investigated in the urban areas of Shenyang city in 2011. The results showed that the use of deicing salts on roads leads to the high accumulation of sodium (352–513 mg•kg-1) and chloride (577–2,353 mg•kg-1) in urban roadside soil. High pH and EC values suggested that the alkaline status and high soluble salts in the soil. High accumulation of deicing salts in roadside soil has been shown to have a phytotoxic effect on pines (Pinus tabulaeformis). Concentrations of Na and Cl in leaves were higher in the roadside plants than the plants appearing healthy in control site. The accumulation of Na and Cl in the needles were present up to an average of 274 mg•kg-1 (24–672 mg•kg-1) and 3,681 mg•kg-1 (786–9,919 mg•kg-1), respectively. It is evident that the deicing salts spray has a significant effect on the accumulation of sodium and chloride in urban roadside soils and needles of Pinus tabulaeformis, as well as the occurrence of visible injuries.