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Direct and Indirect effects and the Long-term Risks of Air Pollution on Forest Ecosystems: Forest Decline and Wood Quality
1993
Bues, C.T. | Schulz, H. (University of Munich, (Germany))
The results of numerous investigations in Europe on potential relationships between forest decline caused by immissions and the wood quality of diseased trees consistently showed the technical properties of wood form diseased trees to be unaffected. Wood from diseased trees can be used without reservation.
Mostrar más [+] Menos [-]Direct Effects of Air Pollution on Physiology of Forest Trees in the Western United States
1993
Bytnerowicz, A. (USDA Forest Service, Riverside, CA (USA). Pacific Southwest Research Station)
Physiological processes of western trees are effected by ozone at concentration over 80 ppb, depending on the duration of the exposures and environmental conditions. At a single fascicle level short-term ozone exposures can cause reduction, no change or increase of stomatal conductance and net assimilation rate. Two seasons of exposures at twice level ozone concentrations caused a significant reduction of stomatal conductance and pigment concentrations in foliage.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]Direct and Indirect effects and the Long-term Risks of Air Pollution on Forest Ecosystems in Latin America
1993
Innes, J.L. (Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf (Switzerland))
The biggest problem facing the forest of Latin America is deforestation. Air pollution also constitutes a threat to some forests, and pollution level will increase in the future. Major problem associated with photochemical smogs have been documented in the mountains around Mexico City and Santiago in Chile. Acidic deposition has been identified in some areas and is known to be affecting forest reserves in rural situations.
Mostrar más [+] Menos [-]Indirect effects and the Long-term Risks of Air Pollution on Tolerant Hardwood Forest Ecosystems in Central Canada
1993
Morrison, I.K. (Forestry Canada Ontario Region, Sault Ste. Marie (Canada))
There is a strong evidence to indicate that sulphates and nitrogen oxides cause increased leaching of base cations, principally calcium and magnesium from soils supporting old-growth sugar maple forest in central Canada. Sugar maple trees sequester Ca, especially in bark. A site low in exchangeable bases might become less productive, if subjected to prolonged high rates of leaching and full tree harvesting.
Mostrar más [+] Menos [-]Direct and Indirect Effects and the Long-term Risks of Air Pollution on Forest Ecosystems: Effects on Soil Nutrition
1993
Guang-Jing Ma | Bai-Zhong Li | Ping Zhang | Jing-shen Liang (Chinese Academy of Forestry, Wan Shou Shan (China). Research Center for Forest Environment)
Atmospheric pollutant can cause direct effects mediated by foliage and indirect effects mediated through soil. Biotic and abiotic factors can confound relationships among nutrient cycling, growth loss and mortality and air pollution. Changes in the soils could result from acidic deposition. Changes could include increased fertility as a result of sulphur and nitrogen input to soils that are deficient in these elements or decreased fertility through ion leaching or mobilization of toxic substances as aluminium.
Mostrar más [+] Menos [-]Direct and Indirect Effects and the Long-term Risks of Air Pollution on Forest Ecosystems: Effects on Soil Micro-organisms
1993
Innes, J.L. (Swiss Federal Institute for Forest, Snow and Landscape Research, Birmensdorf (Switzerland))
The soil biota plays a critical part in the functioning of forest ecosystems. Acidification and heavy metals have the greatest direct effects on the soil biota. However pollutants can have indirect effects through their influence on tree root systems. Acidic deposition can decrease the incidence of mycorrhizal infection, but soil pH and concentration of nitrogen and certain forms of sulphur are also important.
Mostrar más [+] Menos [-]Climate Change and Forest Ecosystems - an Overview
1993
Kraeuchi, N. (Swiss Federal Institute of Technology, Zurich (Switzerland). Department of Forest and Wood Research)
Climate change must be considered an ecological and socio-economic threat. We have to support any measures that are combating climate change. It is currently unknown which climate scenario will come true, and therefore very important to maintain the biological diversity of the forest ecosystems for a wide variety of possible development.
Mostrar más [+] Menos [-]The Swiss National Forest Inventory, an information for the assessment of the condition and long-term changes of Swiss forest
1993
Brassel, P. (Swiss Federal Institute for Forest Snow and Landscape Research, Birmensdorf (Switzerland))
The national forest inventory of Switzerland is a large-scale assessment of the condition and changes in Swiss forests. Some of the most important advantages of the NFI are its permanence, the long-term and flexible inventory design, the high data-quality and the compatibility with the damage inventory.
Mostrar más [+] Menos [-]Direct and indirect effects and the long term risks of air pollution on forest ecosystems: the role of forest health monitoring
1993
Innes, J.L. (Swiss Federal Institute for Forest Snow and Landscape Research, Birmensdorf (Switzerland))
Monitoring of forest health represents an important part of programmes assessing the actual and potential impact of air pollution and climate change on forests. The available information indicates that variation between years is high, indicating that long term time series will be required to identify trends in forest condition.
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