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1

Landscape pattern and genetic structure of a yellow-necked mouse Apodemus flavicollis population in north-eastern Poland

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Gortat T., Gryczynska-Siemiatkowska A., Rutkowski R., Kozakiewicz A., Mikoszewski A., Kozakiewicz M.
Acta Theriologica
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2010
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tom 55
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nr 2
109-121
Reduced connectivity among local populations inhabiting a spatially heterogeneous landscape may restrict gene flow and thus contribute to diminished genetic variation within a population. The aim of this study was to determine the role of geographic distance and habitat barriers in developing genetic structure of a yellow-necked mouse Apodemus flavicollis (Melchior, 1834) population, taking into consideration the spatial organization of the landscape. A field study was carried out in two plots located in NE Poland that differed considerably in terms of the scale of habitat fragmentation: (1) a continuous forest complex, and (2) a mosaic of smaller forest habitats. The plots were separated by a water barrier comprised of a chain of lakes. DNA samples from a total of 654 individuals were examined by microsatellite analysis (5 loci). The results showed that the yellow-necked mouse population was characterized by a poorly pronounced genetic structure throughout the study area, although the statistical significance of F ST for most location pairs indicated that gene flow in the area was not free. The division of the mouse population into three genetically distinct groups clearly demonstrated the significant role of water bodies as a natural barrier effectively hindering free movement of animals and thus gene flow. Analysis of the genetic structure of the mouse population throughout the study area and also within the distinguished groups indicated that the entire study population may be considered as a single metapopulation. Our results suggest that geographic distance alone is not the predominant factor affecting the genetic structure of population, but in the mosaic landscape the relative isolation of individual forest fragments, and barriers hindering movements of individuals and limiting gene flow among local populations played a much more important role.
2

Sinuosity and edge effect - important factors of landscape pattern and diversity

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Stejskalova D., Karasek P., Tlapakova L., Podhrazska J.
Polish Journal of Environmental Studies
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2013
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tom 22
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nr 4
The paper is focused on two crucial landscape-forming aspects: linear elements (watercourses, linear tree plantings, road network) and neighbouring edges of landscape segments, or ecotones. Linear elements accentuate the character of landscape, its division, pattern, and contribute significantly to landscape passability and its diversity. The edges of neighbouring landscape segments not only create the spatial arrangement of landscape, but they also are important habitats for plants and animals. So they are irreplaceable for the maintenance of ecological stability of landscape and they are an important element of its biodiversity. The analysis of trends of changes in the length of linear elements and ecotone edges was performed in three time horizons: in the first half of the 19th century, in the 1960s, and at the present time. The evaluation was done in four model territories. Ous paper evaluates the sinuosity of linear elements (roads and railways, watercourses, dirt roads, linear tree plantings) and the lengths of common borders of segments of arable land – permanent grasslands and arable land – forests.
3

Landscape-level spruce mortality patterns and topographic forecasters of bark beetle outbreaks in managed and unmanaged forests of the Tatra Mountains

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Sproull G. J., Bukowski M., McNutt N., Zwijacz-Kozica T., Szwagrzyk J.
Polish Journal of Ecology
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2017
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tom 65
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nr 1
Bark beetle outbreaks and tree mortality patterns should be better understood to control outbreak impacts. We investigated landscape-level patterns of Norway spruce mortality caused by Ips typographus outbreaks across three periods from 1999–2012 in Tatra National Park (Poland) using high-resolution aerial orthophotos and satellite imagery. Shifts in tree mortality related to elevation, slope, and solar equinox radiation were analyzed with ANOVAs (Tukey's HSD tests). Boosted regression trees were employed to assess the forecasting effectiveness of these variables related to mortality period. Spruce mortality severity increased significantly across time in both managed and unmanaged forests. Management activities did not effectively reduce spruce mortality severity. Mortality severity increased significantly at higher elevations over time, while slope and radiation trends varied. Elevation and radiation were the best forecasters of mortality period, exhibiting moderate predictive ability. Beetle-induced spruce mortality increased significantly in Tatra National Park from 1999–2012, particularly at high elevations. Management strategies aimed at minimizing spruce mortality have been ineffective.
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