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[The state of transboundary air pollution: 1992 update]
1993
Development and transfer of pollution prevention technology
1993
Rappaport, Ann
Direct Effects on Boreal Forest Trees in Northern Europe
1993
Koski, V. (Finnish Forest Research Institute, Vantaa (Finland). Department of Forest Ecology)
Northern species not only tolerate but even benefit vegetatively from a slightly warmer climate than they have been adapted to. If the climatic warming remains below 5 celsius in annual mean temperature, the present forest will not be subject to direct disaster. Reproductive processes are likely to be enhanced through increased flowering and better seed maturation. There are few empirical studies on reproductive biology in new environments.
Show more [+] Less [-]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.
Show more [+] Less [-]Direct and Indirect Effects and the Long-term Risks of Air Pollution on Forest Ecosystems: A Call for Caution in Proper Diagnosis of Causes
1993
Skelly, J.M. (The Pennsylvania State University, (USA). Department of Plant Pathology)
Forest Scientists must recognize that numerous diseases and insect occurrences as well as more subtle environmental stresses are prevalent as causes of changes in forest health. Their interactions often lead to "natural" declines of individual tree species or site-species declines of multiple species. The role of air pollution should be carefully investigated in an integrative sense with these other endemic and sometimes epidemic outbreaks of biotic agents and environmental stresses.
Show more [+] Less [-]Direct and Indirect effects and the Long-term Risks of Air Pollution on Forest Ecosystems: Air Pollutants and Tree Ecophysiology
1993
Matyssek, R. (Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf (Switzerland))
The potential effects of long-term exposures to widespread low but raised concentrations above natural levels in Central Europe are still being discussed. This uncertainty results from an inadequate mechanistic understanding of the influence of air pollutants and other environmental factors of trees.
Show more [+] Less [-]Air Pollution and Forest Condition in Central Europe
1993
Kandler, O. (University of Munich, Munich (Germany).Botanical Institute of University of Munich)
Depending on their concentrations, air pollutants are dangerous to forests. With the exception of some industrial areas in the east, concentrations of air pollutants in Central Europe are below the damaging threshold as shown by the records of the monitoring stations.
Show more [+] Less [-]Climate Change - Potential Impacts on Subalpine Forest Ecosystem
1993
Kraeuchi, N. (Swiss Federal Institute of Technology, Zurich (Switzerland))
The ranges of the ecosystems move when the climatic pattern changes. Simulations have shown that a global warming would cause important changes of the species composition in subalpine forests. Deciduous trees would invade today's subalpine belt. Various conifers would be displaced and migrate into alpine zone. The model simulations are based on the IPCC climate scenarios.
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 [-]Direct and Indirect Effects and the Long-term Risks of Climate Change on Forests: Tropical Deforestation and Carbon Dioxide
1993
Jarvis, P.G. (University of Edinburgh, Scotland (United Kingdom). Institute of Ecology and Resource Management)
Destruction of forests leads to the release of carbon dioxide stored in the wood and also usually results in major releases of carbon dioxide stored in soil. Annual releases of carbon dioxide from destruction of tropical forests was estimated at about 1650 million tonnes per year.
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