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Soil nutrients in a mature natural mixed forest exposed to elevated CO2
2002
Bucher-Wallin, I. K. | Schleppi, P. | Hagedorn, F. | Bucher, J. B. (Swiss Federal Research Institute WSL, Birmensdorf (Switzerland))
Elevated CO2 was shown to influence the nutritional status of exposed ecosystems. In an earlier experiment in model ecosystems in open-top chambers with young spruce and beech, the nitrate concentration of the soil solution was dramatically reduced after 4 years exposure to elevated CO2. This phenomenon was mainly interpreted as an immobilization of nitrogen in the soil. To test if such effects occur also in mature, undisturbed natural forests, we used facilities of the Swiss Canopy Crane project. Here in a mixed 120 years old forest the crowns of 30-35 m high broadleaved trees are fumigated with CO2 during the growing season since spring 2001. According to the results the soil is probably not yet much influenced by the fumigation of the tree crowns, and it is too early to estimate whether the observed nutrient effects are due to the CO2 treatment or to the natural variability of the soil
Show more [+] Less [-]Nutrient concentrations in the foliage of beech (Fagus sylvatica L.) and Norway spruce (Picea abies L. Karst.) plants of a model ecosystem in response to long-term exposure to atmospheric CO2 enrichment and increased N deposition
2002
Landolt, W. | Egli, P. | Pezzotta, D. | Bucher, J. B. (Swiss Federal Research Institute WSL, Birmensdorf (Switzerland))
The biological effects of both elevated CO2 and N deposition on model ecosystem were investigated in the Birmensdorf open-top chamber facility. Each of the 16 chambers was divided into two compartments with a ground area of 3 msub2 and filled with natural unfertilized forest soils from two sites (one acidic, the other calcareous). Elevated CO2 significantly increased O and Zn concentrations in beech leaves and those of Zn in spruce needles on the calcareous soils. Enhanced N deposition also led to a dilution of nutrients and increased N contents
Show more [+] Less [-]Long-term changes of soil chemical parameters in forests of Saxony (Germany)
2002
Raben, G. | Symossek, F. | Katzschner, W. | Gemballa, R. | Karst, H. | Kohler, S. | Nowatzki, O. (Saxon State Institute of Forestry, Pirna (Germany))
Taking into account the results of environmental monitoring in forest ecosystems (European Level I- and II-Programme) showing high degrees of soil acidification and still a widespread exceedance of critical loads by deposited sulphur and nitrogen compounds, the programme of differentiated forest protection liming should continue with site specific doses. On the other hand the programme to restore forest ecosystems with higher stability and to a large extent balanced nutrient cycles has to be carried out in order to minimize internal acid-generating processes
Show more [+] Less [-]Needle surface structure and its relation to nutrient status of Norway spruce under the long-term air pollution influence
2002
Popierova, D. | Mankovska, B. (Forest Research Institute, Zvolen (Slovak Republic))
Emissions, especially of SO2 and to a certain degree of NOx have been reduced markedly in Slovakia during the 90s. Problems related to climate change and especially ozone are increasingly growing. The aim was to evaluate the long-term air pollution effect on forest ecosystems in mountain area with prevailing distribution of spruce through evaluation of spruce needle surface structure in relation to mineral nutrient status of trees. According to strong relationship between the coefficient of epicuticular wax degradation (Q) and accumulation of S and other elements it can be suggested that evaluation of needle surface structure by means of Q well reflects the surface status of needles
Show more [+] Less [-]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
Show more [+] Less [-]Reducing the impact of crop nutrients on the environment
1993
Steen, I. | Williams, T. (European Fertilizer Manufacturers Association, Brussels (Belgium))
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))
Towards integrated national modelling with particular reference to the environmental effects of nutrients
1998
Alkemade, J.R.M. | Grinsven, J.J.M. van | Wiertz, J. | Kros, J. (National Institute of Public Health and the Environment, Bilthoven (Netherlands))
Monitoring of nitrogen compounds on Yakushima Island, a world natural heritage site
1998
Satake, K. | Inoue, T. | Kasasaku, K. | Nagafuchi, O. | Nakano, T. (National Institute for Environmental Studies, Onogawa 16-2, Tsukuba, Ibaraki 305-0053 (Japan))
Nitrogen in Dutch freshwater lakes: trends and targets
1998
Molen, D.T. van der | Portielje, R. | Nobel, W.T. de | Boers, P.C.M. (Institute for Inland Water Management and Waste Water Treatment, Lelystad (Netherlands))