Decline of Montane Boreal Ecosystems in Central Europe and the Southern Appalachian Mountains

摘要

For more than a decade scientists from Western Europe and New England have documented an insidious dieback and/or decline of certain forest types, in particular high-altitude coniferous forests. Silver fir and Norway spruce are undergoing a severe decline in Hartz Mts., Black Mts., and the Bavarian Alps. Similar declines have been reported from western Czechoslovakia. Symptomatology of this syndrome includes chlorosis and abscission of older needles and a dramatic suppression of annual increment and growth. In addition, tree and herbaceous vegetative reproduction is in many cases either suppressed or absent. Recent surveys of the NC Mt. Mitchell (6,684' mean seas level) summit cone areas indicate a similar increment reduction along with symptoms similar to those observed in Europe (i.e. declining, chlorotic, low vigor spruce-fir stands). This decline appears to be in a much earlier stage of progression when compared to the above conditions.