Habitat network analysis of the forest patches of the Bereg Plain based on the carabid fauna
Abstract
For many species, the most probable key to survival is maintaining the connectivity between local populations making migration and gene flow possible. This is probably true for the carabid species (Coleoptera: Carabidae) living in the fragmented forests of the Bereg Plain (NE Hungary and W Ukraine). Based on field data we constructed the landscape graph of the area representing the habitat network of these species. We analysed (1) the positional importance of landscape elements in maintaining the connectivity of the intact network, (2) the effect of inserting hypothetical corridors into the network, and (3) the effects of improving the quality of the existing corridors. Our results set quantitative priorities for conservation practice by identifying what to protect, what to build and what to improve. Several network analytical techniques were used, according to the essentially directed (source-sink) and highly fragmented nature of the landscape graph. We provide conservation priority ranks for the landscape elements and discuss the conditions for the use of the particular indices. Our study could be of extreme relevance considering that the construction of a new freeway through the area is in the planning phase.
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