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The aim of this article is to present the activities of non-governmental organizations for the protection of natural heritage related to implementation of the projects within the Swiss-Polish Cooperation Programme in the focus area: biodiversity and ecosystem protection and the support of the cross-border environmental initiatives. Particular attention was paid to the protection of migration corridors and its legal basis in connection with implementation of the project The protection of the refugium of the Carpathian forest fauna – migration corridors. The study draws on statistical data on the activities of NGOs in the indicated topic area, as well as materials elaborated within the Swiss-Polish Cooperation Programme and the project The protection of the refugium of the Carpathian forest fauna – migration corridors. The protection of natural heritage is the area of activity of approximately 1 in every 20 non-governmental organizations in Poland. The interest in the indicated field of activity is gradually increasing, as well as the awareness of the necessity of taking measures towards protecting the areas allowing for migration of animals.
Determining ecological corridors is crucial for conservation efforts in fragmented habitats. Commonly employed least cost path (LCP) analysis relies on the underlying cost matrix. By using Ecological Niche Factor Analysis, we minimized the problems connected with subjective cost assessment or the use of presence/absence data. We used data on the wolf presence/absence in Poland to identify LCPs connecting patches of suitable wolf habitat, factors that influence patch occupancy, and compare LCPs between different genetic subpopulations. We found that a lower proportion of cities and roads surrounds the most densely populated patches. Least cost paths between areas where little dispersal takes place (i.e., leading to unpopulated patches or between different genetic subpopulations) ran through a higher proportion of roads and human settlements. They also crossed larger maximal distances over deforested areas. We propose that, apart from supplying the basis for direct conservation efforts, LCPs can be used to determine what factors might facilitate or hinder dispersal by comparing different subsets of LCPs. The methods employed can be widely applicable to gain more in-depth information on potential dispersal barriers for large carnivores.
River Vistula, one of the large (1047 km in length) European rivers preserved in semi-natural, dynamic condition, is recognized as important corridor that enables birds and fishes to migrate for long distances. To test whether the Vistula valley provides corridor function also for mammals, field surveys and habitat modelling for six target species: Bank vole Myodes glareolus, Yellow-necked mouse Apodemus flavicollis, Pine marten Martes martes, Beaver Castor fiber, Wild boar Sus scrofa, and Elk Alces alces, were undertaken in the 135 km long fragment of the valley from 529 (Warsaw) to 685 km (Włocławek). The data collected documented the occurrence of at least 51 mammals (5 Insectivora, 14 Chiroptera, 1 Lagomorpha, 16 Rodentia, 11 Carnivora, 4 Artiodactyla), and the highest species richness was noted in the fragment of river valley covered with mixed forests which makes up the protected area called Kampinos National Park. This protected area (385 km²) contains coniferous and mixed forests, inland dunes, wetlands, and mosaic of extensively used meadows, pastures, alder forests and fields. The LARCH (Landscape Ecological Analysis and Rules for the Configuration of Habitat) (Van der Sluis and Romanowski 2005) model outputs indicated the potential for large viable populations of species analysed in the river valley. The LARCH SCAN analysis showed that habitats of modelled species were well connected and their local populations formed highly sustainable network. The spatial cohesion of habitats was generally highest in Kampinos NP and along the fragment of River Vistula from 580 to 618 km. It is concluded that high cohesion of habitats facilitates dispersion of animals and provides potential for gene flow among the populations in the valley. Riparian forests and islands are important for connecting the local populations of mammals of two river banks and are the key elements to provide functional continuity of the corridor along the river in places, where it is discontinued on one bank. The scenario analysis demonstrates potentially negative effects of river regulation and construction of two dams on viability of mammalian populations and spatial cohesion of their habitats. The future corridor function of the River Vistula valley depends mostly on preservation of it’s dynamic, semi-natural condition.
In order to enable migration of plants and animals between various distant ecosystems, it is necessary to maintain ecological corridors between them. Spatial planning, especially that on the local level where spatial shaping methods are directly regulated, plays an important role here.
Along a 4.8 km long stretch of the ecological corridor of the lêza river, 175 patches dominated by Helianthus tuberosus s.l. were found. Among them, about two-thirds are not bigger than 4 m2, but many of the other patches cover areas of several hundred square meters to about 1300 m2. The effect of the H. tuberosus stands on the vegetation of anthropogenic habitats was studied at two sites: one post-agricultural and one post-industrial. At both sites, a system of transects with study plots was laid out. The transects began outside of the H. tuberosus stands (stage A) and penetrated their inside comprising three distinguished stages (B to D) of increasingly higher and denser thickets of sunflower. No significant differences between habitats were found. At both sites, there was a strong decrease in the number and biomass of co-occurring species only in the older stages (C and D) of thicket development, but not at the edges (B), where short H. tuberosus individuals strongly compete with other species.
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