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Hierarchy theory as a guide to mycorrhizal research on large-scale problems.
1991
O'Neill E.G. | O'Neill R.V. | Norby R.J.
Deperissement des forets et pollution atmospherique [pluies acides, degats par region et par essence].
1987
Muller M. | Wunenburger R.
Politique generale de protection de l' environnement en France en matiere de pollution atmospherique [actions du Ministere de l' Environnement, de l' Agence pour la Qualite de l' Air et du Ministere de la Sante].
1987
Legrand H. | Biren J.M. | Jouan M.
Institutions active in environmental science, research and technology in Italy.
1994
Facchetti S.
Protection of the environment has been of public concern for many years in Italy and many institutions here are involved in this field. However, the advantages offered by the improvement of the quality of the environment are not always considered in economic terms, even though a rigorous evaluation of the relationships between economy and environment should help us to better understand how protection of the environment is related to economic development and social benefits.
Afficher plus [+] Moins [-]Soil nutrients in a mature natural mixed forest exposed to elevated CO2
2002
Bucher-Wallin, I. K. | Schleppi, P. | Hagedorn, F. | Bucher, J. B. (Swiss Federal Research Institute WSL, Birmensdorf (Switzerland))
Elevated CO2 was shown to influence the nutritional status of exposed ecosystems. In an earlier experiment in model ecosystems in open-top chambers with young spruce and beech, the nitrate concentration of the soil solution was dramatically reduced after 4 years exposure to elevated CO2. This phenomenon was mainly interpreted as an immobilization of nitrogen in the soil. To test if such effects occur also in mature, undisturbed natural forests, we used facilities of the Swiss Canopy Crane project. Here in a mixed 120 years old forest the crowns of 30-35 m high broadleaved trees are fumigated with CO2 during the growing season since spring 2001. According to the results the soil is probably not yet much influenced by the fumigation of the tree crowns, and it is too early to estimate whether the observed nutrient effects are due to the CO2 treatment or to the natural variability of the soil
Afficher plus [+] Moins [-]Science and policy - to what extent does long-term monitoring of forest ecosystems contribute to policy relevant air pollution issues?
2002
Haussmann, T. (Federal Ministry of Consumer Protection, Food and Agriculture, Bonn (Germany)) | Fischer, R. | Riebau, A.
Following the objective to provide an overview on the spatial and temporal variation in forest condition on a European scale, an extensive systematic survey on more than 6000 so called Level I plots throughout Europe is carried out. Results show a recuparation of crown condition in the mid nineties and a resuming deterioration with nearly a quarter of the sample trees classified as damaged in 2001. Results of statistical evaluations explain the observed variation mainly by weather extremes, insects, fungi and indirect effects of air pollutants via soil acidification or changes in the nutritional status of trees
Afficher plus [+] Moins [-]Reindeer summer pastures and ultraviolet radiation (UV)
2002
Soppela, P. (University of Lapland, Rovaniemi (Finland). Arctic Centre) | Turunen, M. | Heiskari, U. | Forbes, B. | Aikio, P. | Magga, H. | Sutinen, M. L. | Ahman, B. | Helle, T. | Nieminen, M. | Kyro, E. | Lakkala, K. | Huttunen, S. | Uhlig, C.
The aim of the proposed research is to investigate the effects of UV-radiation on chemical composition, palatability and digestibility of summer pasture plants of reindeer. The studies are planned to be conducted in natural peatland ecosystems with (I) enhanced UV-B radiation, provided by UV-B lamps and (II) with UV-filtration experiments with the same plant species in reindeer pastures in the Lappi Reindeer Herding Cooperative in Eastern Finnish Lapland. The results will provide information about the effects of ambient and enhanced UV radiation on summer pastures of reindeer and can be used to evaluate their consequences on reindeer management
Afficher plus [+] Moins [-]Nutrient concentrations in the foliage of beech (Fagus sylvatica L.) and Norway spruce (Picea abies L. Karst.) plants of a model ecosystem in response to long-term exposure to atmospheric CO2 enrichment and increased N deposition
2002
Landolt, W. | Egli, P. | Pezzotta, D. | Bucher, J. B. (Swiss Federal Research Institute WSL, Birmensdorf (Switzerland))
The biological effects of both elevated CO2 and N deposition on model ecosystem were investigated in the Birmensdorf open-top chamber facility. Each of the 16 chambers was divided into two compartments with a ground area of 3 msub2 and filled with natural unfertilized forest soils from two sites (one acidic, the other calcareous). Elevated CO2 significantly increased O and Zn concentrations in beech leaves and those of Zn in spruce needles on the calcareous soils. Enhanced N deposition also led to a dilution of nutrients and increased N contents
Afficher plus [+] Moins [-]Impact of regional pollution load on tree condition and interpretation of assessment methods
2002
Augustaitis, A. (Lithuanian University of Agriculture, Kaunas (Lithuania). Forest Monitoring Laboratory)
Investigation of air pollution impact on tree condition indicates the greatest correlation between pine defoliation and SO2, SO4 and NH4 concentration in the air, NH4 load with precipitation and its pH in the eastern part of Lithuania. In the southern part significant correlation was found between defoliation and SO4 concentration in the air and SO4, NH4 load with precipitation and its pH. No significant correlation was found in the western region of the country, which includes seaside part. Tree age and tree development classes have an essential effect on the correlation significance
Afficher plus [+] Moins [-]Response of coniferous ecosystems to reduction of SO2 and NOx emission in last decade in Poland
2002
Staszewski, T. (Institute for Ecology of Industrial Areas, Katowice (Poland)) | Uzieblo, A. | Kubiesa, P. | Lukasik, W. | Szdzuj, J.
Five permanent plots in pine and spruce stands were established at beginning of the 90s. The sites were situated in a gradient of air pollution level, from the south to the north of Poland. There are presented changes in SO2 and NO2 concentration in the air as well as loads of acidic compounds and the exceedance of critical loads in the period of 1993-2001. Response of the forest ecosystems was evaluated by changes in health status of trees and changes in biodiversity at forest permanent plots. The comparative study revealed an improvement in the health condition of trees and a tendency of ecosystems to regenerate due to greater than 30% decrease in emission in the last decade
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