US EPA

787137 

Journal Article 

[Enhanced ozone strongly reduces the carbon sink strength of adult beech - resume from the free-air fumigation study at Kranzberg Forest] 

Matyssek, R 

2011 

Yes 

Gefahrstoffe, Reinhaltung der Luft / Air Quality Control
ISSN: 0949-8036
EISSN: 1436-4891 

71 

3 

103-107 

German 

WOS:000289183400007 

Ground-level ozone (O-3) has gained awareness as an agent of climate change. In this respect, key results are comprehended from a unique 8-year free-air O-3 fumigation experiment, conducted on adult beech (Fagus sylvatica) at Kranzberg Forest, Germany. A novel canopy O-3 exposure methodology was employed that allowed whole-tree assessment in situ under twice-ambient O-3 levels. Elevated O-3 significantly weakened the C sink strength of the tree-soil system as evidenced by lowered photosynthesis and whole-stem growth, but increased soil respiration. Associated effects in leaves and roots at the gene, cell and organ level varied from year to year, with drought being a crucial determinant of O-3 responsiveness. Regarding adult individuals of a late-successional tree species, empirical proof is provided first time in relation to recent modelling predictions that enhanced ground-level O-3 can substantially mitigate the C sequestration of forests in view of climate change. 

trees fagus-sylvatica; european beech; long-term; risk-assessment; mature beech; exposure; drought; l.; impact; growth