Drobyshev, Igor
- Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences
Abstract
Crown defoliation of oak (Quercus robur and Q. petraea) was analysed in 808 trees during three forest condition surveys (1988, 1993, and 1999) in the southern Sweden. From 1988 to 1999 crown defoliation increased by more than 20%. Changes in crown defoliation were related to the pH in the upper 20-30 cm of the mineral soils, which was closely connected to other measures of soil fertility (cation exchange capacity, CEC and C/N ratio). Trees growing on soils with a high pH (>= 4.00, in BaCl2 filtrate), high CEC and low C/N ratio had significantly lower crown defoliation than trees growing on more acid soils (pH < 4.00), indicating that less favourable soil conditions may further enhance oak decline. Age did not differentiate trees with respect to crown defoliation, indicating that decline in crown condition was not due to an age-related increase in crown transparency. Considering only trees younger than 100 years, a significant interaction was observed between changes in crown defoliation and soil pH. Trees younger than 100 years old growing on more acidic soils had a greater increase in crown transparency than trees on more basic soils between 1988 and 1999. Trees
Keywords
age structure; biotic factors; climate variation; crown defoliation; environmental monitoring; European hardwoods; forest condition; oak decline; soil pH; acidification
Published in
Environmental Monitoring and Assessment
2007, volume: 134, number: 45660, pages: 199-210
Publisher: SPRINGER
SLU Authors
UKÄ Subject classification
Environmental Sciences and Nature Conservation
Publication identifier
- DOI: https://doi.org/10.1007/s10661-007-9610-9
Permanent link to this page (URI)
https://res.slu.se/id/publ/19838