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Direct and indirect effects and the long term risks of air pollution on forest ecosystems: effects and risks on ectomycorrhizae
1993
Brunner, I. (Swiss Federal Institute for Forest Snow and Landscape Research, Birmensdorf (Switzerland))
Two main effects on ectomycorrhizae can be distinguished: direct effects due to a change in the soil chemistry and indirect effects due to a change of the carbohydrate supply from the host trees to the roots.
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 [-]Pedologic and nutritional aspects of enhanced carbon-dioxide storage in forest ecosystems
1993
Huettl, R.F. (Forestry Dept. Kali and Salz AG, Kassel (Germany))
Enhanced forest growth in combination with relatively high Nitrogen deposition may result in further pedologic and nutritional changes and an even greater destabilisation of forest ecosystems.
Mostrar más [+] Menos [-]Socio-economic assessment of global change and air pollution-related forestry damage
1993
de Steiguer, J.E. (USDA Forest Service, Raleigh, North Carolina (USA))
Information on potential forestry losses seems to be crucial to government officials that they can properly assess the costs and benefits of limiting pollution and greenhouse gas emissions. However very few socio-economic assessments of potential losses have been completed.
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.
Mostrar más [+] Menos [-]Meßtechniken zur Messung von Ammoniak in der Umgebungsluft Texto completo
1993
Dämmgen, Ulrich
Plant nutrient management and the environment
1993
Joly, C.
Prevention of water pollution by agriculture and related activities
1993
Burt, J.P. (United States Dept. of Agriculture, Washington, DC (USA))
Improving nitrogen management in irrigated, intensely cultivated areas: the approach in France
1993
Ignazi, J.C. (Comite d'Orientation pour la Reduction de la Pollution par les Nitrates, Paris (France))