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Influence of land cover and structure of ree stands on pollen deposition in Zaborski Landscape Park

100%

Filbrandt-Czaja A. , Deptula M. , Nienartowicz A.

tom 16

The paper presents a comparison of modern pollen deposition in Tauber traps after one-year exposure at two research sites - Laska and Widno, located in the northern part of the Zaborski Landscape Park in the Pomerania Province (Northern Poland). The studied sites were circular in shape with a radius of 2 km and an area of 1256 ha each. They were characterised by similar contribution of forest and non-forest areas, as well as similar species composition and area covered by tree species. Both sites differed, however, in the location of traps in relation to forest areas and distribution of deciduous trees amid pine monocultures. At the former site, a Tauber trap was placed in the open field, i.e. in xerothermic meadow, in the western part of the Laska village. At the latter site, a trap was placed on the borderline between meadows of the Widno village and the surrounding forests. At the site of Laska, scattered deciduous trees occurred mostly in the form of small clusters amid extensive pine monocultures surrounding the village. Whereas at the site of Widno, deciduous tree species covered larger areas in the form of more fertile oak-hornbeam forests, beech forests and birch woods amid pine forests. The size of area covered by tree species and the amount of pollen deposition by these trees were positively correlated at both sites. In addition, the average annual pollen deposition was calculated for each site for seven most abundant tree species during the period of 1999-2010. By comparing the arithmetic means, it was found that the pollen deposition at the site of Widno is higher for most of the studied arboreal species compared with the site of Laska, but these differences are statistically significant only in the case of birch and hornbeam.

Development of forests in the former heathland landscape: changes in the habitat quality, structure of undergrowth, syntaxonomy of phytocoenoses and modern pollen deposition

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Deptula M. , Filbrandt-Czaja A. , Nienartowicz A. , Kaminski D. , Adamska E. , Piernik A. , Lewandowska-Czarnecka A.

nr 2

This study presents changes in the quality of habitats between 1926 and 2013 in permanent units of forest division restored in the 19th century as a result of afforestation carried out in the landscape dominated by heaths and xerothermic grasslands. The research was conducted in the Zaborski Landscape Park, located in the north-western part of the Tuchola Forest − one of the largest forest complexes in Poland. Changes in the habitat quality were determined based on data included in seven consecutive inventory books. Assessment according to the 5-point quality scale was performed on the basis of average height reached by a pine forest stand of a certain age occurring in particular forest subsections. It has been found that the quality of habitat increased over 87 years by two classes, on average from IV to II. The number of species, especially deciduous trees and shrubs listed in inventory books, was an additional parameter expressing the habitat quality. The extent of habitat changes was also determined based on the types of syntaxa, which are represented by relevés forming the time series and made more or less at the same sites by different authors in 1961, 2002 and 2013, i.e. over the period of 52 years. Temporal changes in the structure of phytocoenoses and their syntaxonomic affiliation were determined using the classification and ordination methods. It has been found that in the study area and within the studied time horizon, there was a recession of dry coniferous forest which developed towards mesic (fresh) pine forests. Whereas within the fresh coniferous forest, there were transitions from the poor cladonietosum variant to the mesotrophic typicum variant, or from the typicum variant towards the fertile variant with a large contribution of Fagus sylvatica in the main tree layer and undergrowth. A change in the forest type from a pine monoculture to mixed pine-beech forest was also reflected in the spectrum of modern pollen deposition collected after annual exposures of Tauber traps. In this case, the observations were performed by the same research team over 15 years.