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Effects of SO(2), NO(2), and O(3) on population development and morphological and physiological parameters of native herb layer species in a beech forest.
1989
Steubing L. | Fangmeier A. | Both R. | Frankenfeld M.
Pesticides in rainfall and air in Italy.
1993
Trevisan M. | Montepiani C. | Ragozza L. | Bartoletti C. | Ioannilli E. | Re A.A.M. del
Long-term research in the forest ecosystems under the influence of Gabcikovo hydropower plant
2002
Oszlanyi, J. (Slovak Academy of Sciences, Bratislava (Slovak Republic). Institute of Landscape Ecology)
48 sites were chosen for the ecological research and monitoring in the area influenced by the Gabcikovo hydropower plant. Decrease and exceptional increase of groundwater level was the main factor, which was expected to cause abrupt and intensive changes in production-ecological parameters, in structure and composition of tree, shrub and herbaceous layers. In chosen sites measurements and observations started in 1987. Abrupt and intensive growth of the leaf area index and improvement of health condition of tree and shrub layer was observed
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 [-]Forest health conditions in North America
2008
Tkacz, Borys | Moody, Ben | Villa Castillo, Jamie | Fenn, Mark E.
Some of the greatest forest health impacts in North America are caused by invasive forest insects and pathogens (e.g., emerald ash borer and sudden oak death in the US), by severe outbreaks of native pests (e.g., mountain pine beetle in Canada), and fires exacerbated by changing climate. Ozone and N and S pollutants continue to impact the health of forests in several regions of North America. Long-term monitoring of forest health indicators has facilitated the assessment of forest health and sustainability in North America. By linking a nationwide network of forest health plots with the more extensive forest inventory, forest health experts in the US have evaluated current trends for major forest health indicators and developed assessments of future risks. Canada and Mexico currently lack nationwide networks of forest health plots. Development and expansion of these networks is critical to effective assessment of future forest health impacts.
显示更多 [+] 显示较少 [-]Changes in conifer and deciduous forest foliar and forest floor chemistry and basal area tree growth across a nitrogen (N) deposition gradient in the northeastern US
2007
Boggs, J.L. | McNulty, S.G. | Pardo, L.H.
We evaluated foliar and forest floor chemistry across a gradient of N deposition in the Northeast at 11 red spruce (Picea rubens Sarg.) sites in 1987/1988 and foliar and forest floor chemistry and basal area growth at six paired spruce and deciduous sites in 1999. The six red spruce plots were a subset of the original 1987/1988 spruce sites. In 1999, we observed a significant correlation between mean growing season temperature and red spruce basal area growth. Red spruce and deciduous foliar %N correlated significantly with N deposition. Although N deposition has not changed significantly from 1987/1988 to 1999, net nitrification potential decreased significantly at Whiteface. This decrease in net potential nitrification is not consistent with the N saturation hypothesis and suggests that non-N deposition controls, such as climatic factors and immobilization of down dead wood, might have limited N cycling. Data from the 1999 remeasurement of the red spruce forests suggest that N deposition, to some extent, is continuing to influence red spruce across the northeastern US as illustrated by a significant correlation between N deposition and red spruce foliar %N. Our data also suggest that the decrease in forest floor %N and net nitrification potential across sites from 1987 to 1999 may be due to factors other than N deposition, such as climatic factors and N immobilization in fine woody material (<5 cm diameter).
显示更多 [+] 显示较少 [-]Elaboration of critical load maps in Switzerland
1993
Rihm, B. (Meteotest, Bern (Suisse))
Determination of critical loads of atmospheric pollutants in natural ecosystems, particularly forests. Basic principles. The Vosges project (France)
1993
Dambrine, E. (Institut National de la Recherche Agronomique, Champenoux (France). Centre de Nancy, Microbiologie Biogeochimie et Pathologie des Ecosystemes Forestiers) | Probst, A. | Party, J.P.
The effects of simulated acid precipitation on leaf litter quality and the growth of a detritivore in a buffered lotic system
1988
Garden, A. | Davies, R.W. (Department of Biological Sciences, University of Calgary, Alta. T2N 1N4 (Canada))
Niepolomice Forest - a GIS analysis of ecosystem response to industrial pollution
1997
Weiner, J. | Fredro-Boniecki, S. | Reed, D. | Maclean, A. | Strong, M. (Department of Ecosystem Studies, Institute of Environmental Biology, Jagiellonian University, ul. Ingardena 6, 30-060 Krakow (Poland))