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Soil microorganisms suppressed by emissions of a magnesite plant in the Slovak Republic
2002
Kautz, G. (University of Cologne, Cologne (Germany). Institute of Zoology) | Zimmer, M. | Zach, P.: Kulfan, J. | Topp, W. | Zelinkova, D.
Soil microorganisms are important for plant growth and beneficial for the nutrition and the development of a variety of soil animals. Together with soil invertebrates they also improve nutrients availability in soils. Although not frequent in Europe , magnesite emissions can affect the nutritional status of the vegetation and the survival of soil microorganisms as well as other biota locally, and thus may be crucially responsible for the quality of the entire biotic system. The observed gradients of soil microbial characteristics reflect the physico-chemical properties of soils around the magnesite plant and may be used to predict transitory changes during amelioration
Показать больше [+] Меньше [-]Effects of elevated CO2 and O3 on silver birch rhizosphere and leaf litter decomposition
2002
Kasurinen, A. (University of Kuopio, Kuopio (Finland). Department of Ecology and Environmental Science) | Vapaavuori, E. | Holopainen, J. K. | Holopainen, T.
There is still limited amount of information about the long-term and interactive effects of increased CO2 and O3 levels on larger forest trees growing under natural or semi-natural conditions. Elevated CO2 and O3 might affect the quality and quantity of leaf litter produced and thus change litter decomposition rates and nutrient cycling in the forest ecosystems severely. In this long-term field experiment we studied the effects of realistically increased CO2 and O3 levels on fine root and mycorrhiza growth in ozone-tolerant and ozone-sensitive silver birch clones by root ingrowth core method. We measured rhizosphere soil CO2 efflux plus assessed the total fungal biomass of fine roots and soil by ergosterol analysis
Показать больше [+] Меньше [-]Quality assurance (QA) procedures in the Italian network for forest health monitoring; a six-years experience
2002
Cozzi, A. (Linnaea-ambiente, Firenze (Italy)) | Bussotti, F. | Ferretti, M.
The results indicate that it is possible to reach a good level of reproducibility in a relatively short time. However, quality assurance procedures allow to know the real status of reliability of the field data. More attention must be given to the Level II indices, to select the really useful and informative ones, and to concentrate on these the didactic efforts
Показать больше [+] Меньше [-]Throughfall and canopy interactions in five different tree species in Denmark
2002
Hansen, K. | Bastrup-Birk, A. | Hovmand, M.F. (Danish Forest and Landscape Research Institute, Hoersholm (Denmark))
Acidification of forest soils is dependent on the tree species for several reasons. One reason is that the deposition to deciduous tree species normally is considered lower than to coniferous tree species. This study therefore considers the differences in deposition to different tree species in Denmark. Canopy throughfall and precipitation were collected during the period 1986 to 1999 at three trial species experimental sites in Denmark. At each site the species Norway spruce, sitka spruce, Douglas fir, beech and oak were studied. The paper presents and discusses the differences in canopy exchange processes and dry deposition in different tree species and at different locations
Показать больше [+] Меньше [-]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
Показать больше [+] Меньше [-]Long-term effects of air pollution on spruce forests in the Tatra Mts. - ozone and vegetation studies
2002
Godzik, B. (Polish Academy of Sciences, Krakow (Poland). Institute of Botany) | Fleischer, P. | Grodzinska, K.
Wet-deposited - sulphur and nitrogen pollutants and ambient ozone are important anthropogenic factors affecting forest health. Regular assessment of chemistry of throughfall and precipitation water based on two-week sampling started in 1997. Passive samplers for detection of ozone concentration have been exposed on a network of monitoring stations during vegetation periods since 1998. In addition, in selected locations, UV absorption monitors for continuous O3 measurements were installed in 1999
Показать больше [+] Меньше [-]Unaccounted spatial variability may bias site-related estimates of ozone-like foliar symptoms
2002
Maccherini, S. (Universita di Siena, Siena (Italy). Dipartimento Scienze Ambientali) | Betti, G. | Cozzi, A. | Ferretti, M. | Grohmann, F. | Savini, P.
The assessment of O3-like foliar symptoms is increasingly considered in monitoring programs aimed at evaluating air pollution effects on forests. The results showed considerable spatial and temporal variation of O3-like foliar symptoms: year, subplot adn the interaction between year and plot were found significant factors. Symptoms resulted lower in 2001; there were differences of foliar symptoms between different subplot and overall the variation between years are considerably different according to the plot being considered. These findings suggest that O3-like foliar symptoms recorded on a small plot selected without a formal statistical approach and with no consideration of the apparently high variability of symptoms expression risk to introduce a serious bias in the evaluation of the potential ozone impact at a given site and its trend
Показать больше [+] Меньше [-]Soil acidification in Swiss forest ecosystems
2002
Braun, S. (Institute for Applied Plant Biology, Schonenbuch, (Switzerland)) | Kurz, D. | Fluckiger, W.
Soil water measurements in Swiss forest plots show a decrease of the ratio between base cations and aluminium within last 4 years. The decrease is significant in at least one soil layer in 12 of 14 plots and is strongest in areas with high acid deposition. In some of the soils the critical ratio of 1 is being reached today. The development is compared with model estimates. In Switzerland, 80% of acid deposition is made up by nitrogen compounds
Показать больше [+] Меньше [-]Narrow-band spectral indices for foliage loss of Norway spruce (Picea abies [L.] Karst.) estimation
2002
Rasi, R. (Forest Research Institute, Zvolen (Slovak Republic))
The spectral reflectance curves give important information about investigated objects. High-resolution laboratory spectroradiometric measurements were used to investigate the spectral reflectance properties of spruce twigs with various foliage loss. The spectral reflectance was measured in the range from 400 nm to 1100 nm wavelength with 2 nm spectral sampling interval. Measurements of spectral reflectance were obtained using a LI-COR spectroradiometer LI-1800 equipped with standard 1/2 mm monochromator exit slit measuring 6 nm bandwidth and its external integrating sphere covered with barium sulphate inside
Показать больше [+] Меньше [-]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
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