全國 主要 都市에 綠陰樹로 植栽된 느티나무의 健康度 測定과 이를 利用한 大氣汚染狀態 推定

Abstract

This study was conducted to measure shade tree health in major cities and to test the possibility of using the health data to indirectly estimate status of air pollution in the same areas. Zelkova serrata Makino planted as a shade tree in six largest cities and three industrial complexes was measured in mid August for growth increment, visible leaf damage, bark pH, chlorophyll and β-carotene contents, and tree vitality. The results were compared with those of healthy trees in three mountain areas as a control. Chlorophyll and P -carotene were extracted in dimethyl sulphoxide solution and quantified by spectrophotometry, while tree vitality was estimated by measuring electrical resistance in the cambium using Shigometer. Growth parameters such as new shoot length, number of leaves, or width of annual rings varied widely in various locations. Visible leaf damage was observed in most of the sites except mountain areas, with heaviest damage in industrial complexes. Chlorophyll and b -carotene contents, bark pH, and tree vitality were lower in six major cities and lowest in industrial complexes, compared to those in mountain areas. Tree vitality was positively correlated with chlorophyll(?=0.58) and 8 -carotene content(?=0.55). and negatively correlated with degree of leaf damage. Tree health can be estimated most successfully by combining data on visible leaf damage, chlorophyll and P -carotene contents and electrical resistance. Among the 19 sites surveyed in Seoul metropolitan areas, west side of Kangnam(south of River Han) where Kuro and Yongdungpo industrial complexes were located showed lowest tree health and Kangnam showed lower tree health than Kangpuk(north of River Han). It is concluded that Zelkova serrata trees are sensitive to air pollution and can be used as a bioindicator to indirectly monitor air pollution status in large cities and industrial complexes.