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The response of the forest ecosystem to the reduction of TPP SO2 emissions with emphasis on the nutrient cycling
2002
Simoncic, P. | Kalan, P. | Kraigher, H.: Levanic, T. | Urbancic, M. | Vilhar, U. (Slovenian Forestry Institute, Ljubljana (Slovenia))
Selected parameters of the nutrients cycling process for forest ecosystem were investigated in period 1989-2000 at Prednji Vrh in the area affected by the Sostanj thermal power station. In the year 1995 desulphurization of exhaust gases from the TPP Sostanj caused considerable reduction of SO2 emission. We could not find serious tree-ring width decline in spruce. In the year 1956 and 1978 tree-ring widths rapidly declined. In the year 1995 slight icrement recovery could be observed. One probably climatically (drought) induced pointer year (1992) occurred
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]Spatial variability of some topsoil character in a declining forest site (Krkonose National Park, Czech Republic)
2002
Zanini, E. | Caimi, A. | Santoni, S. | Bonifacio, E. (DIVAPRA-Chimica Agraria, Grugliasco (Italy))
45 sites were selected and sampled on the transects and according to the first results of the spatial analysis, 15 more sites were added where useful for the optimal interpolation. Topsoils were sampled including both the soil organic horizons and the more superficial mineral horizon, frequently E, if reached. The depth of the organic horizons, the grass cover, ranked by its hydrophilic character, related to the incipient hydromorphy visible where Norway spruce is more declining, and the Norway spruce health status were systematically recorded
显示更多 [+] 显示较少 [-]Effects of big polluters on biodiversity of northern terrestrial ecosystems
2002
Kozlov, M.V. (University of Turku, Turku (Finland). Section of Ecology)
Impacts of big polluters on adjacent ecosystems can be seen as long-term unintentional experiments. Contrary to the common guess, results of these experiments may be used to address basic ecological problems, like diversity - stability and diversity - productivity relationships, as well as evaluate general effects of disturbance on ecosystem structure and functioning. Toxicity of pollutants plays a leading role at early stages of forest decline, while transformation of forests into birch woodlands and industrial barrens is accelerated by positive feedback's acting primarily via changes in microclimate
显示更多 [+] 显示较少 [-]A global overview of the long-term effects of air pollution on forest trees and ecosystems
2002
Bastrup-Birk, A. (Centre of Forest, Landscape and Planning, Hoersholm (Denmark)) | Kozlov, M. | Thienhoven, M. van
This paper aims to integrate existing information on effects of air pollution on main forest tree species of economic importance, mainly on growth and reproduction. Gaps in knowledge and areas for future research will be identified
显示更多 [+] 显示较少 [-]Diagnosis of pollution effect on Slovak forest ecosystems
2002
Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic))
Presented paper based on long-term and systematic research of the negative effect of pollutants and of the content of the elements in particular parts of forest environment (the years 1965/2002) proves of the importance, need and justificatin of the research on given subject. Knowing the elemental composition of pollutants as to its quality and quantity is basic precondition with diagnosing the effect of polluted air on forest environment. For the needs of practice three main pollution deposition types (acid, alkaline and ammonia) and 8 subtypes were established. They represent changes of forest ecosystems caused by different substances from pollutants
显示更多 [+] 显示较少 [-]Conditions of natural regeneration of Norway spruce ecosystems in the Krkonose mountains
2002
Cudlin, P. (Academy of Sciences of the Czech Republic, Ceske Budejovice (Czech Republic). Institute of Landscape Ecology) | Godbold, L. | Bonifacio, E. | Egli, S. | Fritz, H. W. | Chmelikova, E. | Kowalik, P. | Martinotti, M. G. | Moravec, I. | Nicolotti, G. | Zanini, E.
The aim of the international EU project was to characterize the status, conditions, and constraints for natural regeneration of Norway spruce (Picea abies [L.] Karst.) ecosystems in different stage of forest decline on three permanent research plots in the Giant Mts., to assess whether the biotechnological measures are necessary to support a natural regeneration at each plot. There were not ascertained any fundamental differences in basic soil types of three permenent research plots. No significant differences were observed in diversity of fungal and bacterial rhizospheric populations, including ectomycorrhizal symbionts
显示更多 [+] 显示较少 [-]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
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