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Needle surface structure and its relation to nutrient status of Norway spruce under the long-term air pollution influence
2002
Popierova, D. | Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic))
Emissions, especially of SO2 and to a certain degree of NOx have been reduced markedly in Slovakia during the 90s. Problems related to climate change and especially ozone are increasingly growing. The aim was to evaluate the long-term air pollution effect on forest ecosystems in mountain area with prevailing distribution of spruce through evaluation of spruce needle surface structure in relation to mineral nutrient status of trees. According to strong relationship between the coefficient of epicuticular wax degradation (Q) and accumulation of S and other elements it can be suggested that evaluation of needle surface structure by means of Q well reflects the surface status of needles
Afficher plus [+] Moins [-]Assessment of ozone air pollution injuries on forest vegetation in the Transalpine region of Lombardy (Italy) and Canton Ticino (Switzerland)
2002
Ballarin-Denti, A. (Universita Cattolica di Brescia, Brescia (Italy). Dip. Matematica e Fisica) | Bussotti, F. | Cozzi, A. | Krauchi, N. | Gerosa, G. | Schaub, M. | Skelly, J. M. | Tagliaferri, A.
Many previous studies evidenced very high levels of air pollution by ozone between the North Italy (Lombardy) and the Southern Switzerland (Canton Ticino). These levels are mostly attributed to the influence of the large urbanized area of Milan and to the urban and industrial settlements in the Po Valley. Recent researches revealed the existence of spread foliar ozone-like symptoms in many native plant species, both in the Swiss and in Italian sector. Experiments carried out in open top chambers in Canton Ticino allowed us to attribute the foliar symptoms to the ambient air pollution levels
Afficher plus [+] Moins [-]The progress and perspectives of ILTER research in Poland
2002
Zalewski, M. (Polish Academy of Sciences, Warsaw (Poland). International Centre for Ecology)
The general conclusions of Warsaw ILTER meeting was that following ILTER philosophy, ecological processes integrity can be maintained on the basis of profound knowledge on the rate of changes, hierarchy of driving forces and resistance and resilience of ecosystems. To achieve such complex understanding of these processes there is a need , first to collect and analyze broad spectrum of data possibly standardized by methodology and next permanently exchange information with coordinators from other countries and regions. As a consequence the participants suggested to extend the initial number of 6 sites situated mostly at National Parks and MAB Biosphere Reserve by the new sites representing broader scope of ecosystems and wider range of its anthropogenic modifications. This should allow to define the regional hierarchy of factors deteriorating the ecological systems and create better scope for comparative studies for global environment
Afficher plus [+] Moins [-]Moderation of CO2 induced gas exchange and growth responses by elevated tropospheric O3
2002
Karnosky, D. F. (Michigan Technological University, Houghton (USA). School of Forestry and Wood Products) | Sober, A. | Sharma, P. | Kubiske, M. | Isebrands, J.G.
Stimulation of photosynthesis by elevated CO2 has been consistently found for aspen but not for maple. Similar responses have been shown for growth. In contrast, O3 causes decreased levels of photosynthesis and growth in aspen but does not appear to impact sugar maple significantly. When the pollutants co-occur, CO2 induced enhancements in photosynthesis and growth are moderated so that trees in CO2 and O3 treatments respond similarly to those in control rings. In this presentation, we will provide a physiological interpretation of our results in modelling growth response under future atmospheric conditions
Afficher plus [+] Moins [-]Integrative study on relationships between atmospheric deposition and forest condition in German forest ecosystems using multivariate statistics
2002
Wellbrock, N. (Applied University of Forestry, Eberswalde (Germany). Institute of Soil Science) | Riek, W. | Wolf, B.
Interactions between atmospheric deposition and nutrient status or soil condition were studied using correlation analysis of the principal factors values for the year 1989. In case of both species, especially sulphur and calcium (factor 1) input is related to high foliar content of sulphur and calcium. The same influence can be detected for nitrogen (factor 3). Nitrogen inputs on Scots pine stands influenced the magnesium sufficient in a negative way
Afficher plus [+] Moins [-]Critical loads and exceedances for eutrophication and acidification in Flanders
2002
Neirynck, J. | Langouche, D. | Ridder, K. de | Wiedman, T. | Roskams, P. (Institute for Forestry and Game Management, Geraardsbergen, (Belgium))
Critical loads were estimated for over more than 1400 receptors supporting forest vegetation in northern Belgium using simple mass balance method. Necessary data were derived from old historical soil database, recent data from forest surveys, meteo data, level I and II plots and regional studies concerning elemental sequestration in woody biomass. Deposition estimates were performed with the OPS-model, which had been validated with deposition measurements of N and S in 6 level II plots over the period 1994-1998. In addition, an edge enhancement factor was calculated to account for enhanced deposition in plots situated in forest edges
Afficher plus [+] Moins [-]The changes of Scots pine (Pinus sylvestris L.) tree stem and crown increment under decreased environmental pollution
2002
Augustaitis, A. | Juknys, R. | Kliucius, E. | Augustaitiene, I. (Lithuanian University of Agriculture, Kaunas (Lithuania). Faculty of Forest)
The main objective of this paper is to analyse regeneration regularities of damaged trees during the period of decreased environmental pollution load. Investigations concentrated on Scots pine tree height and radial increment, branch length increment, amount of branches on the verticil and needle and whole crown mass. Model trees were selected in 3 stands located on 3.5, 10 and 21 km from the plant according to their development classes and condition
Afficher plus [+] Moins [-]European oak decline (Quercus robur and Q. petraea) and population genetic structures
2002
Hertel, H. | Zaspel, I. (Institute for Forest Genetics and Forest Tree Breeding, Waldsieversdorf (Germany). Federal Research Centre for Forestry and Forest Products)
Phenotypical differentiation between and within populations was observed. During the last decade, vitality decreased for both species in the observation plots in accordance with the general trend in Germany. Differences between the species were detected for single symptomatic traits like bark necroses. The genetic analyses with isozyme markers as well as cpDNA haplotypes resulted in remarkable differences between species
Afficher plus [+] Moins [-]The influence of air pollution on contents of pollutant in some components of nature environment in the protected landscape area Ponitrie
2002
Dureckova, E. (State Nature Protection of Slovak Republic, Nitra (Slovak Republic). Protected Landscape Area Ponitrie)
Since 1990 the investigations of quality of some components of nature environment were carried out on selected permanent plots in Protected Landscape Area Ponitrie focused on pollutant contents. The increased concentration of pollutants in precipitation from the top of the Vtacnik Mts. indicates firstly the effect of the nearby thermal power station, secondly documents an increased immission load on forest ecosystems in ridge positions of these mountains
Afficher plus [+] Moins [-]Neutron activation analyses for air pollution studies: some preliminary results of the European moss-survey 2000
2002
Ermakova, E. | Frontasyeva, M. (Joint Institute for Nuclear Research, Dubna (Russia). Frank Laboratory of Neutron Physics)
Instrumental neutron activation analysis (INAA) at the Joint Institute for Nuclear Research is presently being used in several projects on air pollution studies supported by the International Atomic Energy Agency and the Plenipotentiaries of the country members of JINR. They involve moss and lichen biomonitoring techniques and GIS technology for constructing geographical maps of atmospheric deposition patterns of key heavy metals and a number of additional elements. Multi-element INAA is considered to be a reference analytical technique providing most reliable results for the bulk elemental content due to the non-destructive way of sample preparation for analysis
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