| Popis: |
Deicing salt is used to melt snow and ice on the road for traffic safety during the winter season, which accumulates in the roadside vegetation and induces visible injuries. The damage may accelerate particularly when it coincides with early spring leaf out. In order to better understand the response mechanisms, C. kousa (3-year-old) was irrigated twice prior to leaf bud in a rhizosphere with solutions of 0.5, 1.0, and 3.0% calcium chloride (CaCl2) concentration, that were made by using an industrial CaCl2 reagent practical deicing material in Seoul. Physiological traits of the mature leaves were progressively reduced by CaCl2 treatment, resulting in reductions of total chlorophyll contents, chlorophyll a:b, photosynthetic rate, quantum yield, stomatal conductance, FV/FM, and NPQ. On the contrary, light compensation point and dark respiration were increased at high CaCl2 concentration. A decrease in intercellular CO2 concentration by stomatal closure first resulted in a reduced photosynthetic rate and then was accompanied by low substance metabolic rates and photochemical damage. Based on the reduction of physiological activities at all treatments (CaCl2 0.5%, 1.0%, and 3.0%), C. kousa was determined as one of the sensitive species to CaCl2. |
