The Damage of Deicing Salt on Two Spruce Tree Species Planted along Roadsides in Northern Japan

抄録

　The growth of two spruce species (Picea abies (L.) Karst., and Picea glehnii Masters) planted along roadsides is often reduced by salt stresses. To analyze the toxicity of deicing salts, we measured needle lifespan, and the concentration of chlorophyll, sodium, and chlorine of the two spruce species at damaged and healthy sites. In the needles of P. abies large amounts of sodium and chlorine were detected, especially in winter. Chlorophyll concentration in needles of P. abies decreased, and needle shedding accelerated. By contrast, in P. glehnii no difference was found in the concentration of sodium, chlorine, and chlorophyll, and in survivorship of needles between summer and winter. Therefore, we concluded that effect of salt spray was larger for the site of P. abies than that of P. glehnii.