The effects of ozone stress on tree growth and vigor in the Sierra Nevada of California, USA : Air Pollution and Forest Decline. 14th International Meeting for Specialists in Air Pollution Effects on Forest Ecosystems

1989

S. 289-291

3 Abb., 1 Tab., 3 Lit. Ang., En, Zfsg. En

Unselbständiges Werk

200034690

We investigated the effect of chronic ozone exposure on ponderosa pine in the Sierra Nevada of California. Ponderosa pine was sampled in 56 stands (1400 trees), with half of the stands in areas with documentation of ozone injury (asymptomatic). Ozone injury to needles was high in the southern Sierra and low in the north. There was no evidence of recent growth reductions on a regional basis, although some sites had recent growth reductions. Several sites had recent growth increases that are probably related to timber management practices. Most of the growth trends in this century are correlated with regional precipitation patterns.