Aerial Photography and Valuation of Norway Spruce Decline Evolution in the Ardennes

1989

S. 155-171

6 Abb., 3 Tab., 19 Lit. Ang.

Unselbständiges Werk

200014656

A diagramm of the decline symptoms evolution has been carried out using infrared color aerial photographies (scale 1/5 000) taken in 1983 and 1985: after a stratification of Norway Spruce stands (age, 2 levels; general healt state, 3 levels), 10 permanent plots including 10 trees have been identified in each of the 6 strata. The health state of 70% of the trees doesn't change. The other 30% improve or degrade following different ways with a privileged propensity to the chlorosis stage. A study taking into account ecological factors would permit a better analysis of stratification criteria.