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Indirect effects and the Long-term Risks of Air Pollution on Eastern North American Temperate Forest Ecosystems: Insect Outbreaks
1993
Chappelka, A.H. (Auburn University, Alabama (USA). School of Forestry)
Air pollutants cause subtle changes in natural resistance that can prediscope plants to insect attack. The majority of reports in the area of plant-pollutant-insect interactions have been correlative in nature. In the last ten years, there has emerged a growing body of literature, the vast majority with herbaceous crops, reporting on cause-effect relationships among insects and their hosts.
Afficher plus [+] Moins [-]Indirect effects and the Long-term Risks of Air Pollution on Eastern North American Forest Ecosystems: Pathological Problems
1993
Chappelka, A.H. (Auburn University, Alabama (USA). School of Forestry)
Air pollutants such as ozone may affect tree host-pathogen interactions by altering plant tissue susceptibility, plant resistance, pathogen virulence and inoculum density. Ozone has been shown to weaken trees in natural stands and increase their susceptibility to invasion by plant pathogens, such as Heterobasidion annosum. Ozone has also been shown to enhance disease development by fungi that are normally saprophytic in nature.
Afficher plus [+] Moins [-]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.
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