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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
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]Natural regeneration of Norway spruce ecosystems in the Krkonose mountains: conditions and constraints
2002
Cudlin, P. | (Academy of Sciences of Czech Republic, Ceske Budejovice (Czech Republic). Institute of Landscape Ecology) | Chmelikova, E. | Falta, V. | Gronsky, R. | Sera, B. | Polak, T.
Results on germination, growth and mortality of Norway spruce seedlings during period 1994-2000 in various types of soil cover were summarized and evaluated. The years 1992 and 1995 were recorded as high seed production years, while the year 2000 is considered as the low seed production year. In 1999 natural seedlings from various soil covers were examined for lateral root and root tip development. The results of germination and surviving of Norway spruce seedlings are discussed in relationship with the stage of the decline of Norway spruce ecosystems
显示更多 [+] 显示较少 [-]Evaluation of environmental impact on Pinus mugo Turra as bioindicator in Subalpine belt of Julian Alps in Slovenia
2002
Batic, F. (University of Ljubljana, Ljubljana (Slovenia). Biotechnical Faculty) | Mavsar, R. | Rozman, A. | Sircelj, H. | Simoncic, P. | Turk, B.
Determination of the streses operating on a forest ecosystem demands the use of several bioindication methods. Air quality indicators were assessed from an inventory of forest decline based on the assessment of tree crowns and lichens. Photosynthetic pigments, ascorbic acid and major macro nutrients were studied in mountain pine (Pinus mugo Yurra) needles as indicators of physiological and biochemical stress. Analyses were carried out at selected forest plots and transects in predominantly unpolluted areas within Triglav National Park, Julian Alps, Slovenia. It was assumed that air pollutant input in forest ecosystems is of two kind, e.g. local from the air pollutin sources in the valleys on the North-West part of tha national park and transboundary source at high altitudes
显示更多 [+] 显示较少 [-]Nitrogen budget on a limestone site in the Austrian Alps
2002
Herman, F. (Institut fur Immissionsforschung und Forstchemie, Vienna (Austria). Bundesamt und Forschungscentrum fur Wald) | Smidt, S. | Englisch, M. | Feichtinger, F. | Gerzabek, M.: Haberhauer, G. | Jandl, R. | Kalina, M. | Zechmeister-Boltenstern, S.
While nitrogen input exceeded the critical loads of the WHO (1995), nitrogen deficiency and nutrient imbalances were verified by needle analyses. The atmospheric input of inorganic nitrogen was higher than the nitrogen output in 50 cm soil depth. A tracer experiment with 15N helped to prove that not more than half of the applied nitrate could be discharged. This allows the conclusion that nitrogen is stored in the system and that the site cannot yet be said to be saturated with nitrogen. The same result was also obtained by modelling
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]Implementation of remediation measures in municipal forests of Spisska Nova Ves
2002
Stefanik, J. (Municipal Forests, Spiska Nova Ves (Slovak Republic))
Spis region is due to long-term effect of air pollution one of the most polluted regions in Slovakia. Decline of trees, mostly of spruce, was recorded here altogether with disintegration of forest stands. Incidental felling and its volume is frequently connected with local source of air pollution from iron-ore works Rudnany and Kovohuty. Long-range transfer of air pollutants from Poland (Katowice) plays a certain role in air pollution as well. In the year 1994 the damaged stands were classified into the zones of endangerment, the period of the validity of forest management plan was shortened and there were proposed measures for forest regeneration
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]Dynamics of forest sites after liming
2002
Kunes, I. | Ulbrichova, I. (Czech University of Agriculture, Prague (Czech Republic). Faculty of Forestry)
The contribution summarizes outputs of annual measurements that were made in the eleven-year long period of observation (1991-2001). In this case, the liming had markedly positive effect on prosperity of spruce plantation up to now. The limed variants "surface" and "planting pit" show lower values of the total mortality than the control variant. Furthemore, the mean value of the periodic annual increment of the trees of the control variant is clearly lower than the mean values of the variant "surface" and the variant "planting pit". According to soil analyses the above described forms of liming do not seem to induce any serious negative changes within soil in this case
显示更多 [+] 显示较少 [-]Forms - an integrated forest monitoring system in Denmark
2002
Bastrup-Birk, A. | Johannsen, V.K. (Centre of Forest, Landscape and Planning, Hoersholm (Denmark))
A FORest Monitoring System (FORMS) has been implemented in Denmark in order to gain and deliver knowledge and information for operational and strategic decisions concerning nature and environment. FORMS integrate four national monitoring programmes. Forest condition monitoring is performed on 52 permanent plots distributed on a 16 x 16 km grid. FORMS gives a systematic and representative assessment of the resources in and development of the forests in Denmark, includes the monitoring of important processes in the forest ecosystem and follows the use of forest for recreational purposes
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