Effects of Ozone on the Growth of Norway Spruce exposed in Open-Top Chambers

1989

6 Tab., 13 Lit. Ang.

Unselbständiges Werk

2693

200037854

Four year old seed propagated Norway spruce (Picea abies (L.) Karst) trees were exposed in open-top chambers to either charcoal filtered air or to non- filtered air added ozone. The trees were exposed from mid July to mid October 1986 and from early May to mid October 1987. A destructive harvest was done November 1986 and no effects of ozone were seen on needle length. The variance components from these data were used for planning of the 1987 growth measurements. In 1987 budburst was delayed about one week on the ozone exposed trees. The same delay could be seen for shoot and needle elongation. In mid-summer no differences in shoot length persisted, but needles on ozone fumigated trees remained shorter. A destructive harvest in November showed no significant differences in current year shoot dry matter production. The influence on the trees of the delayed budbreak will be discussed.