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Succession of Tree Species on Drained Bogs in ‘Brzozowe Bagno koło Czaplinka’ Nature Reserve, NW Poland

Jagodziński A. M., Dyderski M. K., Horodecki P., Rawlik K., Gdula A. K.

Polish Journal of Ecology

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2018

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Vol. 66, nr 4

352--368

EN

Succession of woody species on bogs is a process limited by high groundwater table. In the case of drainage, this limiting factor becomes suppressed and succession may accelerate. The aim of the study was to assess the development of tree stands on a raised bog influenced by drainage and wild fire and to assess the dynamics of woody species encroachment. The study was conducted in the ‘Brzozowe Bagno koło Czaplinka’ nature reserve in NW Poland, where the originally unforested peat bog was influenced by peat harvesting, drainage and fire over 100 years. The diameter at breast height of tree species and natural regeneration were assessed. Six types of tree stands were distinguished: open bog, bog forest with Pinus sylvestris, early-, mid- and late-successional bog forest with Betula pubescens and pioneer forest with Populus tremula, which occurred in the post-fire sites. After ca 100 years of human activity on an unforested peat bog, dense forest emerged on almost all of the study area. Drainage and wildfire influenced tree stand structure. The course of succession most probably goes from open bog to pine bog forest and early-, mid- and late-successional birch forests. Regeneration of B. pubescens is a crucial phase of woody species succession, because this species creates suitable conditions for growth of late-successional species.

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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.

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Teledetekcyjna analiza sukcesji brzozy omszonej {Betula pubescens Ehrh.) na terenie Parku Narodowego Thingvellir, Islandia

Strzeliński P., Wencel A.

Roczniki Geomatyki

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2006

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T. 4, z. 2

139-145

EN

The paper presents the use of satellite remote sensing to vegetation succession analysis in Thingvellir National Park in Iceland. The research had the below aims: 1) analysis of succession of common white birch (Betula pubescens Ehrh.) 2) an assessment of quantity of birch trees 3) classification of basic types of vegetative cover 4) analysis of possibilities of use of remote sensing data in Thingvellir National Park. The paper encompassed analysis and interpretation of SPOT5 satellite images of the park and its surroundings (taken in 2003) and digital maps produced on the basis of aerial photographs and field observations (from the years 1955.1978). The analysis has covered fenced part of the park (5002 ha). Within the framework of field work, decision of number and kind of vegetation classes was made. As much as 4 classes were fixed and verified in the field . grass cover, moss cover, broad-leaved/birch cover, coniferous cover. The maps of the scale: 1:50 000 i 25 000 were made, and then verified in the field. The vegetation classes constituted respectively: grass cover . 1.0% of the park area, moss cover . 19.0%, broad-leaved trees/birch . 54%, coniferous trees . 0.3%. There was also the class .others. (25.7% of the park area), which encompasses all areas having no meaning for final results and areas which are impossible to classify. Selected data concerning birch (on the basis of SPOT5 and field control) were compared to data from the years 1972.1978. Unfortunately, precise quantity comparison was impossible due to differences in accuracy of data (date from the years 1972.1978 are less precise). Hence only area comparison was made. In the years 1955.2003 area covered by birch did not changed considerably, still it is the dominant class in respect of area. Presently common white birch covers 2705 ha which is 54% of Thingvellir National Park area within borders from before 2004 and 66% of land area. The project concerned the forests and birch thickets in Thingvellir National Park commissioned by Skógrćkt Ríkisins and RALA (Institut of Forest and Agricultural Research). The main works on project have been done from the beginning of July to the end of September 2005.