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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 [-]Leaf morphology and gas exchange in holm oak (Quercus ilex L.) trees in different environments
2002
Lakso, K. (University of Oulu, (Finland). Department of Biology) | Paoletti, E. | Huttunen, S.
Two holm oak (Quercus ilex L.) sites in Tuscany, Central Italy, were studied in July 2000. Leaf morphological characteristics (area, dry weight, specific dry weight, water content, epicuticular wax amount, stomatal density) and leaf fluorescence were measured. Ozone flux into the leaves was calculated on a stomatal conductance basis. Among the measured parameters, only stomatal density and wax amount significantly differed between the sites. This response might indicate an adaptation to air pollutants, of which tropospheric ozone might be of the greatest importance
显示更多 [+] 显示较少 [-]Ozone-specific microscopic symptoms in the mesophyll cells and their relation to nutrient status of Norway spruce needles - a field study
2002
Kivimaenpaa, M. (University of Kuopio, Kuopio (Finland). Department of Ecology and Environmental Science) | Jonsson, A. M. | Stjernquist, I. | Sellden, G. | Suttinen, S.
The results showed that ozone specific symptoms can be detected in the needles of mature spruces in the southern Sweden with AOT40 considerably lower than the present critical level of 10 000 nl 1sup-1. The results could be expressed as an index per tree and needle generations, but also as a single value for forest stand allowing statistical tests. The results from this study support the general hypothesis and results from exposure and field studies that low nutrient concentrations or nutrient deficiency modifies the ozone response in plants. The results also show that together with low nutrition status ozone may affect the hardiness status of the needles
显示更多 [+] 显示较少 [-]Needle traces of Scots pine as air pollution indicators
2002
Konopka, B. (Forest Research Institute, Zvolen (Slovak Republic))
Needle retention, needle density, height and radial increments were surveyed on Scots pine (Pinus sylvestris L.) in four forest regions, In the each forest region research was conducted on seven about 45-year-old pines. The Needle Trace Method (NTM) was used to determine needle retention and needle density along the main stem retrospectively for the last four decades. The NTM invented by Kurkela and Jalkanen is based on the examination of the vascular bundles connecting the needles and shoot pith. There are presented the long-term average values of needle retention in the particular forest regions, their differences. Needle retention and needle density reflected air pollution stress on the pines
显示更多 [+] 显示较少 [-]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 [-]Ozone symptoms in native herbaceous species in Southern Alps: field assessment and laboratory verification
2002
Gerosa, G. (Universita degli Studi, Milano (Italy). DiProVe) | Marzuoli, R. | Cesana, V. | Ballarin-Denti A. | Bussotti, F.
Small attention has been still addressed to the study of ozone effects on seminatural vegetation. Following this direction we selected an ozone heavily exposed area in Northern Italy, where the development of visible injuries on leaves of common pasture herbs were observed. The selected area, an alpine pasture located at Moggio belongs to the Level II permanent monitoring network of the ICP-Forest program. The ozone exposure mapping exercise made on the whole regional domain estimated for this area an AOT40f of 32000 ppb.h as 1999 and 2000 years average
显示更多 [+] 显示较少 [-]Assessment of ozone visible symptoms in the field - perspectives of quality control
2002
Bussotti, F. (University of Florence, Florence (Italy)) | Schaub, M. | Cozzi, A. | Krauchi, N. | Ferretti, M. | Novak, K. | Skelly, J. M.
Two field exercises for the assessment of foliar visible ozone symptoms were performed during the "2nd UN/ECE ICP-Forests Intercalibration Course on the Assessment of Ozone Injury on European tree Species" organised by the WSL in collaboration with the University of Florence, Linnaea ambiente, and the PSU. The exercises were conducted at the Lattecaldo OTC research facility in Southern Switzerland and on the Moggio Level II plot in Northern Italy from 22-24 August 2001. 48 participants represented 21 countries. There are given objectives and results and conclusions from both sites
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
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