| 要旨トップ | 日本生態学会全国大会 ESJ55 講演要旨


一般講演(口頭発表) G2-11

EFFECTS OF SIMULTANEOUS OZONE AND FLUORANTHENE EXPOSURE ON THE EVERGREEN CONIFER JAPANESE RED PINE (Pinus densiflora sieb et zucc.)

*Oguntimehin Ilemobayo, Sakugawa Hiroshi

Forest decline in Japan has long been traced to air pollution and acid rain/fog, with ozone having high tree damaging records. This study investigated the eco-physiological changes brought to the evergreen conifer, Japanese red pine, by simultaneous fumigation of O3 (O) and fluoranthene (F), a four ring polycyclic aromatic hydrocarbon, in a 90 d period. Seedlings were exposed singly or combined to 10 μM fluoranthene and O3 (3 ppm h in the first 60 d, or 6 ppm h in the last 30 d period) in open top chambers. After 90 d, O+F treatment showed negative effects on the needle visual symptoms, net photosynthesis rate at near saturated irradiance, stomatal conductance,photochemical efficiency of PS II in the dark, total chlorophyll content and Chl a :Chl b ratios. F treatment showed similar results but in lesser magnitude compared with F+O treatment. O treatment alone showed no significant negative effect, probably due to its low concentration in the first two months; in most cases, its effects are same with the control. Mannitol(M) additions mitigated O+F & F negative effects. Fluoranthene deposited on needle surfaces of Japanese red pine presents greater ecological damages risk to the red pine at low O3 concentration. The ubiquitous nature of fluoranthene combined with increasing trends of O3 effects on vegetation should be a major global environmental interest.

日本生態学会