Stress-physiological response patterns in spruce needles relate to site factors in a mountain forest : 3rd EUROSILVA Workshop, Obergurgl, Austria, September, 10-14, 1998

1999

2 Abb., 13 Lit.

Unselbständiges Werk

5943

200086251

Spruce trees are exposed to a complex of environmental factors at natural stands. The patterns of physiological plant responses allow conclusions regarding the stress combinations. At particular field sites small scale site factors, e.g. edaphic conditions, contribute to the stress level of trees together with large scale environmental factors such as altitudinal gradients. In the present paper, physiological response patterns of spruce trees (Picea abies (L.) Karst.) are related to large scale and small scale environmental factors. A principal component solution containing six accumulated components. Component scores were calculated by a two-way analysis of variance (ANOVA) with the large scale factor "altitude" and the small scale factor "water supply", in order to evaluate differences between sites and plant responses. Statistical trends for an altitude effect on scores were observed for antioxidants and pigment ratios (chlorophyll a/b and chlorophylls/carotenoids). For the effect of the site type (good or deficient water supply) significant correlations between water deficiency and antioxidant concentrations could be found. An independent support for this result was provided by measurements of osmotic potentials in saturated needles, indicating that enhanced contents of ascorbate were correlated to more negative osmotic potentials. This statistical approach showed that smale scale edaphic factors (e.g. deficient water supply) decisively contribute to the stress level of spruce trees.