Refine search
Results 1-3 of 3
Direct and Indirect effects of Air Pollution on Forest Ecosystems: the Attempt of a Resume of Scientific Investigations Carried out in Nortrhine-Westphalia/FRG during the last Decade
1993
Prinz, B. (Landesansalt fuer Immissionsschutz, Essen (Germany))
Since the beginning of the 80's, a wide-spread damage to Norway spruce has occurred, mainly characterized by the light-induced decay of chlorophyll in magnesium-deficient needles. Damage also occurs in deciduous trees, especially in beech. To clarify the causes of the damage in Northrine-Wesphalian forests, extensive investigations have been carried out, which combined experimental techniques and epidemiologically orientated surveys.
Show more [+] Less [-]Status and Trend of Deposition Rates in Spruce Stands of Baden-Wuerttemberg (Germany)
1993
Hildebrand, E.E. (Forest Research Institute Banden-Wuerttemberg, Freiburg (Germany))
Deposition rates in Baden-Wuerttemberg, which are monitored by sampling grid, mostly exceed critical loads. This applies especially for nitrogen input and the deposition of total acidity. In a periodic inventory of tree nutrition on a basic grid of 4 km, regions abundant and persistent Mg and K deficiency could be identified.
Show more [+] Less [-]Effects of Acidic Deposition on Calcium Nutrition of Spruce/fir Forests in the Eastern U.S.: Implications for Physiological Processes, Growth, and Climate Interactions
1993
McLaughlin, S.B. (Oak Ridge National Laboratory, Oak Ridge, TN (USA))
Calcium avaiability to forests has been shown to be reduced by acidic deposition in several ways including: increased leaching from foliage, increased leaching from soils, and decreased availability from poorly buffered soils when aluminium is mobilized. Studies documented that acidic deposition has altered the growth and vigour of red spruce during the past three decades by changing calcium availability.
Show more [+] Less [-]