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Progressive methods of increasing the survival of planting stock in the reforestation of localities affected by air pollutants
2002
Tucekova, A. | Sarvas, M. (Forest Research Institute, Zvolen (Slovak Republic))
Possibilities of the use of progressive methods in artificial regeneration of areas affected by air pollutants are namely modification of soil environment, active protection of planting stock against root desiccation, use of containerized planting stock for artificial regeneration of clearings, which resulted from air pollution
Afficher plus [+] Moins [-]Probabilistic sampling for monitoring pollution effects on forest sites
2002
Fattorini, L. (Universita di Siena, Siena (Italy). Dipartimento di Metodi Quantitativi) | Ferretti, M.
The present paper presents a list of probabilistic sampling procedures and subsequent statistical analysis, which may achieve this goal without a considerable increase of field effort
Afficher plus [+] Moins [-]Development trends of forest soils water regime under changing ecological conditions
2002
Tuzinsky, L. (Technical University, Zvolen (Slovak Republic). Forestry Faculty)
Forest ecosystems water balance research is very complicated because of forest influence upon individual components of the water balance. Global climate changes represent a real threat for forest ecosystems. In hydric area these changes concern especially thermal balance and resulting increased evapotranspiration, time and spatial distribution of precipitation
Afficher plus [+] Moins [-]The contributing role of SO2 and drought in forest decline of Austrian pine in coastal Croatia
2002
Diminic, D. (University of Zagreb, Zagreb (Croatia). Faculty of Forestry) | Hrsovec, B. | Potocic, N.
This case study confirms the role of air pollution impact on forest susceptibility to other abiotic and biotic detrimental factors. It is however very important to take into account numerous contributing factors in order to interpret or predict the degree of damage correctly
Afficher plus [+] Moins [-]Monitoring of sulphur load in black pine (Pinus nigra Arn.) cultures at various distances from Plomin power plant, Istria, Croatia
2002
Seletkovic, I. | Potocic, N. (Forest Research Institute, Jastrebarsko (Croatia))
Black pine (Pinus nigra Arn.) was chosen as bioindication species for several reasons. Black pine stands are located throughout Istria, at various distances from the above mentioned power plant. Black pine does not shed needles in the autumn, thus prolonging their exposure to sulphur dioxide emissions. Also neeedles stay on branches for several years, giving us the possibility to analyse the effect on older needles
Afficher plus [+] Moins [-]Assessment of exceedance of critical levels for ozone in Slovak forest ecosystems
2002
Pavlendova, H. | Mindas, J. (Forest Research Institute, Zvolen (Slovak Republic))
For assessment of ozone risks to forests we used ozone thresholds and air quality guidelines set by several international organizations for protection of vegetation. We also used spatial modelling for estimation of basic ozone characteristics. Calculations of models were performed in the environment of the programme Idrisi 32. The spatial coverage of ozone monitoring network in the Slovak Republic has insufficient density. Ozone data come from two sources; SHMI/EMEP database of ozone concentrations from 4 monitoring stations and ozone database of FRI from 3 monitoring stations
Afficher plus [+] Moins [-]Impact of elevated O3 trembling aspen (Populus tremuloides MICHX.) leaf epicuticular waxes and elemental composition of leaves
2002
Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic)) | Karnosky, D. F. | Percy, K. | Ermakova, E. | Frontasyeva, M.
Foliage of three trembling aspen clones differing in O3 tolerance from Rhinelander, Kenosha and Kalamazoo were examined for 24 elements in the year 2001 and they were analyzed by INAA at reactor IBR-2, by AAS Varian 400 and by elemental analyzer LECO SC 132 and SP 228. In the fofliage of trembling aspen we found no statistically significant difference in the concentration of 22 elements except for K and Ni between clones. For the concentrations of elements between localities we found statistically significant difference for Al, Ba, Ca, Cd, Cl, Co, Cu, La, Mo, Na, Ni, Pb, Sm, Sr and Zn
Afficher plus [+] Moins [-]The Hungarian ILTER sites and their activities in 2002
2002
Kovacs-Lang, E. | Kertesz, M. | Toth, J. A.
The Hungarian ILTER Network consists of three sites representing the characteristic biomes in the country: lake Balaton ILTER site, Sikofut oak forest ILTER site, and the Kiskun sand forest-steppe ILTER site. Hungarian ecologists have developed broad multidisciplinary research projects, which can meet both the requirements of international research standards and the domestic needs of nature conservation and environment protection. Hungarian policy and decision makers have also recognised the importance of long-term ecological research. As a consequence different grants such as Hungarian R + D "Szechenyi", EU FWS Projects, OTKA and OTKA-NSF Projects, Joint grant of Ministry of Environment and the Hungarian Academy of Sciences were awarded in the last 2-3 years, what could create the basis of national and international research cooperations of Hungarian ILTER sites
Afficher plus [+] Moins [-]Mechanised site preparation and restoration of degraded site
2002
Ulbrichova, I. | Podrazsky, V. (Czech University of Agriculture, Prague (Czech Republic). Faculty of Forestry)
It was performed the study of the humus forms, quantity and pedochemical characteristics, further the study of plantation growth, and the dynamics in the period of 1994-1999. Negative impacts of the bulldozing were documented, acidification in the period 1994-1999 and the ameliorative role of the birch stand as well
Afficher plus [+] Moins [-]Macro and microscopic effects of polluted seasprays on Pinus halepensis needles in El Saler Natural Park (Valencia, Eastern Spain)
2002
Calatayud, V. (Fundacion CEAM, Valencia (Spain)) | Della Rocca, G. | Paoletti, E. | Sanz, M. J.
Coastal forest decline due to seasprays has been reported from all continents, both on broadleaves and conifers. The main cause has been identified in the presence of surfactants. Sea winds transport these substances to the leaves, where they are absorbed via cuticula and stomata producing indirect and also direct damage. The scope of this work is the macroscopic and microscopic assessment of the long term effects of polluted seasprays on Aleppo pines in natural conditions from the Saler coastline (Eastern Spain) inwards. Surfactants may be involved in the damage to Aleppo pine in El Saler as more severe episodes of damage have been observed in the last decade
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