Nutritional effects triggered by the extreme summer 2003 in the free air ozone fumigation experiment at the Kranzberger Forst

Abstract

Since the year 2000 mature beech and spruce trees were treated in a Weld experiment with double ambient ozone concentrations. Elevated ozone had no inXuence on average single leaf biomass and there were also no ozone eVects on leaf nutrient concentrations in climatic normal years. However, the extraordinary dry summer 2003 triggered signiWcant diVerences between the fumigated and control trees. For beech in the year after the drought event the control trees surprisingly had signiWcantly lower foliar levels of K and P than in former years, whereas the ozone exposed trees showed no signiWcant nutritional eVects. There are indications, that the trees exposed to double ambient ozone were already adapted to higher ozone values, whereas the control trees experienced extraordinary high ambient ozone concentrations in the dry and sunny summer 2003. For spruce in autumn 2003 and 2004 ozone treated trees had signiWcantly higher foliar levels of K in current year needles than control trees, an eVect which cannot be thoroughly interpreted yet on the basis of the dataset available.

Nutritional Status of Major Forest Tree Species in Germany

“…Thus, it must be assumed that older needles had element contents in the year of formation that are comparable to contents of the current needle year. However, element contents in foliage can vary from year to year, especially during or after climatically extreme years (Göttlein et al 2009;Jonard et al 2009;Schleppi et al 2000). This may be a problem for the evaluation of the dataset if there were a systematic deviation of element contents in the respective needle-formation year at all NFSI sites.…”

The ground-level ozone concentration in forest and urban environments in central Slovakia

“…The forest in our study area consisted mainly of Fagus sp. considered a strong producer of isoprene by Benjamin and Winer ( 1998 ) and, at the same time, is less affected by ozone stress (Göttlein et al, 2009 ). Lime trees and low vegetation grow in the immediate vicinity of the inner city, both emitting a large amount of BVOCs.…”