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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.
显示更多 [+] 显示较少 [-]Restoration of functioning forest ecosystems in the Krusne Hory Mts.
2002
Podrazsky, V. | Karas, J. (University of Agriculture, Prague (Czech Republic). Faculty of Forestry)
Research project main aims are coordinating, summarizing and making interpretation from the research results from the region of interest. Further targets are to focus, concentrate and promote research activities of relevant departments of the Faculty of Forestry in this area. Intention of organising institution is to create a material, grouping together research results available from the Ore Mts., forming a basis for results exchange and launching the data as well as for results utilisable in the forest practice in this region
显示更多 [+] 显示较少 [-]Foliar elements of Scots pine across the transect from the ammonia emission source (1995-1998)
2002
Kupcinskiene, E. (University of Agriculture of Lithuania, Kaunas (Lithuania). Kaunas-Akademia)
Significant correlations (p0.05) were found between the concentration of elements in the c needles and the distance of the sites from nitrogen ferilizer factory (NFF): the amounts of C, K, Mg, Zn, and Rb in the c+1 needles were increasing, whereas concentrations of N, P, Al, Mn, Cu, Ni, Sr and Cd were decreasing alongside the transect from NFF. Statistical analyses performed on logarithms and estimation of components of variance by maximum likelihood has shown that the age of the needles and the sites were the most important, while year of sampling was much smaller source of variance. Only a few significant differences were found comparing the amount of elements in Scots pine needles collected in four-year space
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]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
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