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Air pollution status and forest health in the Retezat National Park, Romania
2002
Badea, O. (Forest Research Institute, Bucharest (Romania)) | Popescu, F. | Barbu, I. | Bytnerowicz, A. | Musselman, R. | Gancz, V. | Postelicu, D. | Vasile, C.
Ozone is a well-known phytotoxic agent causing damage to vegetation in parts of North America and Europe. Transboundary or long-range transport of ozone from Western Europe and the generation of ozone from local and regional precursors results in increasing ozone concentrations in Central and Eastern Europe, including the Carpathian Mountaians. Other air pollutants such as sulphur dioxide, nitrogen oxides, ammonia and heavy metals may also affect the health of Carpathian forests. During the 2000-2002 summer seasons, concentrations of ozone, sulphur dioxide, nitrogen oxides and ammonia were monitored with passive samplers. Results of those measurements will be used for development of GIS models of spatial and temporal distribution of air pollutants
显示更多 [+] 显示较少 [-]Physiological responses of Ailanthus altissima Desf. young plants in an area with high ozone pollution levels
2002
Bussotti, F. (Universita di Firenze, Firenze (Italy). Dipartimento di Biologia Vegetale) | Desotgiu, R. | Grossoni, P. | Gravanio, E. | Rodriguez, R.M.
Ailanthus altissimia Desf. is a non-native species spread throughout the Southern Europe as invasive plant. It demonstrated to be very sensitive to ozone and ozone-polluted environment, develops brownish stipples on the upper leaf surface. In the 2001 summer 12 young plants were placed in a site near the city of Florence (Italy), where high levels of ozone were experienced. Six of them were regularly watered and six were watered only when the wilting of their leaves was evident. Regular assessments were done during the experiment. They concerned growth, production of new leaves, dead and shedding of old leaves, visible symptoms of damage, stomatal conductance and CO2 uptake, chlorophyll fluorescence. The results suggest that the sensitivity to ozone of watered plants is connected to their higher growth ratio and stomatal conductance. Ozone plays a more important role than drought in producing foliar stress conditions
显示更多 [+] 显示较少 [-]Effects of preparatory stands on forest site restoration
2002
Remes, J. | Podrazsky, V. (Czech University of Agriculture, Prague (Czech Republic). Faculty of Forestry)
The main aims of the preparatory stands in air pollution areas are growth development, successfull dynamics of the plants and fast creation of the stand microclimate with favourable effect on soil conditions. This process is documented by height and diameter increment. The results confirm different growth dynamics of the particular species. Larch is the species with the best growth dynamics of selected species on experimental plots. On the other hand, beech is the worst species for reforestation in this condition. One of the causes could be damage by frost
显示更多 [+] 显示较少 [-]Response of subarctic tree seedlings to solar UV radiation
2002
Turunen, M. (University of Lapland, Rovaniemi (Finland). Arctic Centre) | Suttinen, M. L. | Derome, K. | Norokorpi, Y. | Lakkala, K.
The response of Betula pubescens Ehr., B. pendula Roth and two provenances of Pinus sylvestris L. to solar ultraviolet radiation were investigated in a UV exclusion field experiment during the 1997-1999 growing seasons in Finnish Lapland. The seed-grown seedlings were grown under UV-B exclusion and UV-B/UV-A exclusion as compared to control treatment and ambient plants. The only significant impacts of UV exclusion were found in P. sylvestris provenance Enontekio. Longer-term field studies are needed to detect the cumulative characteristics of the UV responses
显示更多 [+] 显示较少 [-]Long-term effects of pollutants on forest vegetation in Central Spis region
2002
Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic))
Pollution problems in forest ecosystems resulting from 100 year long operation of three smelter complexes in Central Spis are reviewed. Original data are presented with respect to temporal and spatial trends of nitrogen, sulphur and heavy metal pollution, and elemental composition of individual aerosols on leaf surface. Spruce stands in Central Spis are loaded by pollutants 1.7 times more than are critical values and the highest concentrations of As, Fe, Hg, and N were found in this region. Low Tatra National Park was the cleanest region where no element maxima were found
显示更多 [+] 显示较少 [-]Heavy metals and pedogenic processes in the Krkonose National Park (Czech Republic)
2002
Bonifacio, E. | Santoni, S. | Zanini, E. (Universita di Torino, Grugliasco (Italy). DIVAPRA Chimica Agraria)
Remarkable differences were found in soil development on three sites. At Modru Dul (the least damaged site) Sopdosols and Inceptisols were found, in Alzbetinska (moderately damaged) Entisols are common, while in Mumlavksa hora (highly damaged) the representative soils are several kind of Podzols, with variable degree of drainage restriction and organic soils. The heavy metal content is always rather low and the vertical distribution does not indicate any appreciable contribution of atmospheric contamination
显示更多 [+] 显示较少 [-]Contamination of beech and oak by pollutants in area of magnesite plant
2002
Mankovska, B. | Tucekova, A. (Forest Research Institute, Zvolen (Slovak Republic)) | Novak, J.
The magnesite plants Jelsava and Lubenik emitted in the 80s 30 000 tons of magnesite dust and heavy metals and 4000 tons of SO2 per year, what caused an extreme damage to the vegetation in the area around of about 500 km2. For the determination of 3 zones of endangerment we used pollution index values. In each pollution zone we demarcated experimental plots and carried out soil analyses. Forest stands polluted by magnesite dust belong to alkaline air pollution type
显示更多 [+] 显示较少 [-]Changes in forest ecosystems under the influence of alkalizing the environment pollutants
2002
Armolaitis, K. | Stakenas, V. | Raguotis, A. (Lithuanian Forest Research Institute, Kaunas (Lithuania))
The alkalinization has a positive influence on soil microflora abundance. The number of ammonifiers nearby the plant is greater by 2-4 times than in relatively unpolluted soils of the same type, while the amount of denitrifiers and anaerobic nitrogen-fixing microorganisms even by 20-50 times. Alkalinization has induced biological soil activity. The data obtained are compared with the data of analogous studies conducted on forest ecosystems affected by acidifying pollutants
显示更多 [+] 显示较少 [-]Can air pollution influence spruce bark beetle populations in the Central European mountains?
2002
Turcani, M. (Forest Research Institute, Banska Stiavnica (Slovak Republic). Forest Station) | Grodzki, W. | Fleischer, P. | Novotny, J.
Bark beetle populations were estimated periodically each year in 50 ha plots using a series of pheromone traps and through the dissection of 0.5 m sections of infested trees. Data were recorded on several parameters including the volume of infested trees, captures in pheromone traps, number of attacks, and the presence and relative abundance of related bark beetle species. In the period 2000-2001 3 transects were established in the High Tatra Mts., where captures in pheromone traps were recorded and compared with air pollution represented by ozone
显示更多 [+] 显示较少 [-]Chloroplast microsatellite markers monitoring genetic differentiation of Picea Abies [L.] Karst. in response to air and soil pollution
2002
Schubert, R. | Muller-Starck, G. | Metzger, H. G. | Riegel, R. (Technical University of Munich, Freising (Germany). Weilhestephan Center of Life and Food Sciences)
The chloroplast genome has been widely addressed to describe genetic diversity in tree species with regard to phylogeographic studies. In contrast, there is little information on the pattern of genetic differentiation in tolerant and sensitive tree populations, responding to different types of environmental stress. The results demonstrate that chloroplast microsatellites markers are useful tools for elucidating and for testing the pattern of genetic differentiation in stress-exposed populations of Norway spruce, offering to prove the feasibility of marker-aided selection in future
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