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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.
Показать больше [+] Меньше [-]Contribution of ambient ozone to Scots pine defoliation and reduced growth in the Central European forests: A Lithuanian case study
2008
Augustaitis, Algirdas | Bytnerowicz, Andrzej
The study aimed to explore if changes in crown defoliation and stem growth of Scots pines (Pinus sylvestris L.) could be related to changes in ambient ozone (O(3)) concentration in central Europe. To meet this objective the study was performed in 3 Lithuanian national parks, close to the ICP integrated monitoring stations from which data on meteorology and pollution were provided. Contribution of peak O(3) concentrations to the integrated impact of acidifying compounds and meteorological parameters on pine stem growth was found to be more significant than its contribution to the integrated impact of acidifying compounds and meteorological parameters on pine defoliation. Findings of the study provide statistical evidence that peak concentrations of ambient O(3) can have a negative impact on pine tree crown defoliation and stem growth reduction under field conditions in central and northeastern Europe where the AOT40 values for forests are commonly below their phytotoxic levels.
Показать больше [+] Меньше [-]Ozone distribution and phytotoxic potential in mixed conifer forests of the San Bernardino Mountains, southern California
2008
Bytnerowicz, Andrzej | Arbaugh, M (Michael) | Schilling, Susan | Frączek, Witold | Alexander, Diane
In the San Bernardino Mountains of southern California, ozone (O(3)) concentrations have been elevated since the 1950s with peaks reaching 600 ppb and summer seasonal averages >100 ppb in the 1970s. During that period increased mortality of ponderosa and Jeffrey pines occurred. Between the late 1970s and late1990s, O(3) concentrations decreased with peaks approximately 180 ppb and approximately 60 ppb seasonal averages. However, since the late 1990s concentrations have not changed. Monitoring during summers of 2002-2006 showed that O(3) concentrations (2-week averages) for individual years were much higher in western sites (58-69 ppb) than eastern sites (44-50 ppb). Potential O(3) phytotoxicity measured as various exposure indices was very high, reaching SUM00 - 173.5 ppmh, SUM60 - 112.7 ppmh, W126 - 98.3 ppmh, and AOT40 - 75 ppmh, representing the highest values reported for mountain areas in North America and Europe.
Показать больше [+] Меньше [-]Global topics and novel approaches in the study of air pollution, climate change and forest ecosystems
2016
Sicard, Pierre | Augustaitis, Algirdas | Belyazid, Salim | Calfapietra, Carlo | De Marco, Alessandra | Fenn, Mark | Bytnerowicz, Andrzej | Grulke, Nancy | He, Shang | Matyssek, Rainer | Serengil, Yusuf | Wieser, Gerhard | Paoletti, Elena
Research directions from the 27th conference for Specialists in Air Pollution and Climate Change Effects on Forest Ecosystems (2015) reflect knowledge advancements about (i) Mechanistic bases of tree responses to multiple climate and pollution stressors, in particular the interaction of ozone (O3) with nitrogen (N) deposition and drought; (ii) Linking genetic control with physiological whole-tree activity; (iii) Epigenetic responses to climate change and air pollution; (iv) Embedding individual tree performance into the multi-factorial stand-level interaction network; (v) Interactions of biogenic and anthropogenic volatile compounds (molecular, functional and ecological bases); (vi) Estimating the potential for carbon/pollution mitigation and cost effectiveness of urban and peri-urban forests; (vii) Selection of trees adapted to the urban environment; (viii) Trophic, competitive and host/parasite relationships under changing pollution and climate; (ix) Atmosphere–biosphere–pedosphere interactions as affected by anthropospheric changes; (x) Statistical analyses for epidemiological investigations; (xi) Use of monitoring for the validation of models; (xii) Holistic view for linking the climate, carbon, N and O3 modelling; (xiii) Inclusion of multiple environmental stresses (biotic and abiotic) in critical load determinations; (xiv) Ecological impacts of N deposition in the under-investigated areas; (xv) Empirical models for mechanistic effects at the local scale; (xvi) Broad-scale N and sulphur deposition input and their effects on forest ecosystem services; (xvii) Measurements of dry deposition of N; (xviii) Assessment of evapotranspiration; (xix) Remote sensing assessment of hydrological parameters; and (xx) Forest management for maximizing water provision and overall forest ecosystem services. Ground-level O3 is still the phytotoxic air pollutant of major concern to forest health. Specific issues about O3 are: (xxi) Developing dose–response relationships and stomatal O3 flux parameterizations for risk assessment, especially, in under-investigated regions; (xxii) Defining biologically based O3 standards for protection thresholds and critical levels; (xxiii) Use of free-air exposure facilities; (xxiv) Assessing O3 impacts on forest ecosystem services.
Показать больше [+] Меньше [-]Polish mountain forests: past, present and future
1997
Grodzinska, K. | Szarek-Lukaszewska, G. (W. Szafer Institute of Botany, Polish Academy of Sciences, Lubicz 46, 31-512 Krakow (Poland))
The effects of excess nitrogen deposition on young Norway spruce trees. Part I. The soil
1994
Wilson, E.J. | Skeffington, R.A. (National Power Research and Engineering, Windmill Hill Business Park, Swindon, SN5 6PB (United Kingdom))
Glutathione status and glutathione reductase activity in spruce needles of healthy and damaged trees at two mountain sites
1993
Schmieden, U. | Schneider, S. | Wild, A. (Institut fur Allgemeine Botanik, Johannes Gutenberg-Universitat, 55099 Mainz (Germany))
Evaluation of ozone injury on foliage of black berry (Prunus serotina) and tall milkweed (Asclepias exaltata) in Great Smoky Mountains National Park
1997
Chappelka, A. | Renfro, J. | Somers, G. | Nash, B. (School of Forestry, Auburn University, Auburn, AL 36849 (USA))
Deterioration of forests in the Sudety Mountains, Poland, detected on satellite images
1997
Bochenek, Z. | Ciolkosz, A. | Iracka, M. (Institute of Geodesy and Cartography, Remote Sensing and Spatial Information Centre-OPLIS, ul.Jasna 2/4, 00-950 Warsaw (Poland))
The effects of excess nitrogen deposition on young Norway spruce trees. Part II. The vegetation
1994
Wilson, E.J. | Skeffington, R.A. (National Power Research and Engineering, Windmill Hill Business Park, Whitehill Way, Swindon, Wiltshire (United Kingdom))