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1

Nitrogen deposition and flux through three birch stands (Betula pubescens Ehrh.) in the Kampinos National Park (central Poland)

Kram K.

Polish Journal of Ecology

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2008

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Vol. 56, nr 4

605-612

EN

Nitrogen flow through birch stand canopies was studied in the Kampinos National Park (large forested area with inland dunes and wetlands close to Warsaw) during the growing seasons (April-October) of 2005-2006. The amount of nitrogen deposition including main forms like NO[3], NH[4], organic N and the aerosolgaseous fraction of deposition were estimated as well as the influence of birch canopies on this process. Because a method of "artificial foliage" allows to measure an aerosol-gaseous fraction of deposition a gradient of rain collectors equipped with artificial foliage of known surfaces were used. The results were compared with amounts of nitrogen measured in the throughfall of three birch forests. All stands (age 20.50 years) were rather similar, but stand II has smaller LAI (Leaf Area Index = 2.5 m[^2] m[^-2]) than stands II and III (3.8 and 3.9 m[^2] m[-2]). It was found that nitrogen deposition in the Kampinos National Park is rather high - 1.6 kg ha[^-1] month[-1]. Ammoniumnitrogen made almost half of this value, organic nitrogen - over one third, and nitrate-nitrogen constituted the rest. Aerosol-gaseous input significantly made the deposition increased only in the case of nitrate-nitrogen, but deposition of ammonium- and organic nitrogen were similar and independent of catching leaf area. All fractions of nitrogen were effectively taken up during their passing through birch canopies (57% of nitrogen deposition was retained). Generally two thirds of deposited ammonium-nitrogen, more than half of organic N, and one third of nitratenitrogen were taken up by birch canopies. However, uptake efficiency of all N forms was lower for stand with smallest leaf area with no statistically significant retention of organic N.

2

The influence of low frequency magnetic field upon cultivable plant physiology

Rochalska M.

Nukleonika

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2008

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Vol. 53, suppl. 1

17-20

EN

The 16 Hz frequency and 5 mT magnetic flux density as well as alternating magnetic field influence the field germination physiological yield-forming features and the yield of sugar have been investigated. The profitable influence of the investigated factor at physiological yield-forming features, causing an increase in sugar beet root and leaf yield, was shown. The beneficial influence on the yield is especially clear in unfavourable weather conditions.

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Wybrane zdalne metody szacowania biomasy roślinnej w ekosystemach leśnych jako podstawa systemu raportowania bilansu węgla

Chirrek M., Strzeliński P., Wencel A., Zawiła-Niedźwiecki T., Zasada M., Jagodziński A.

Roczniki Geomatyki

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2007

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T. 5, z. 4

7-16

EN

Effects of increasing CO2 content in the atmosphere of Earth have been widely discussed for a long time and found their expression in a form of the .Kyoto Protocol.. The document shows various ways of reducing the CO2 content. Forest management is listed as one of such possibilities. Thus, the important issue arises to monitor carbon amount accumulated or released as a result of forest ecosystem management as well as to predict its changes depending on various scenarios. The importance of this problem persuaded the General Directorate of State Forests to fund a research project entitled .The Carbon balance in biomass of the major forest forming species in Poland.. The goal of the project is to elaborate and validate allometric equations and expansion factors for determining the biomass of forest stands. Methods to assess amount of carbon accumulated in forest ecosystems as well as methods of detecting changes in carbon accumulation and dynamics resulting from various ways of forest management were also to be elaborated. The first stage of the research, planned for years 2007.2010, is to be performed on about 300 sample plots representing different age classes and sites for 8 major forest tree species and 12 species of shrubs. Empirical equations and expansion factors for determining biomass of trees, shrubs, forest floor, and carbon sequestered in stands will be worked out based on direct and indirect measurements of various forest attributes. The valuable element of the project is a possibility of data integration and comparison of various research methods (satellite and airborne imagery, airborne and terrestrial laser scanning, hemispheric images). As a result of the project, also answers to the following questions are expected: What is the influence of LAI, determined with the use of various methods (hemispheric images, airborne and satellite imagery, and airborne and terrestrial laser scanning), on the accuracy of tree biomass and stand carbon balance assessment? What is the role of vegetation indices on tree biomass assessment accuracy? Does the terrestrial laser scanning significantly increase accuracy and precision, and shorten time of tree, stand and forest floor plants. measurements and their biomass assessment?

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Influence of species composition and forest age on leaf area index

Kram K.

Polish Journal of Ecology

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1998

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Vol. 46, no 1

75-88

EN

Investigations of leaf area index (LAI) were performed in forest stands of pine, beech as well as birch, alder, spruce, larch and oak using the LAI-2000 Plant Canopy Analyser made by American corporation LI-COR. Canopy LAI has been found to differ considerably depending on both dominant tree species and stand age. From among the species examined spruce exhibited the highest LAI amounting to 10.0 m^2 m^-2, where other species had much lower LAI-s (within a range 1.6-6.3 m^2 m^-2).Canopy LAI increased rapidly in young stands attained a peak at approximately age 20 and decreased slowly thereafter. It has been revealed that projected leaf area of an individual tree increases linearly as the tree grows older.