Evaluating the Functional Connectivity of Natura 2000 Forest Patch for Mammals in Romania

Abstract Maintaining and improving landscape connectivity represents a central objective in biodiversity conservation. The present study aims to evaluate the functional connectivity of the Romanian Natura 2000 forest sites for mammals, and to determine the importance of individual forest patches in maintaining landscape connectivity. We established three groups of mammals according to the dispersion distance and the average home-range size: small mammals (1 km; 1 ha), intermediate (10 km; 100 ha) and large mammals (100 km; 1000 ha). For measuring the connectivity we used a graph theory approach and the software CONEFOR 2.6. The importance of each patch as an indicator for the connectivity of forest surfaces was determined using a binary index, the Harary index (dH). Forest surfaces included in the Natura 2000 network present a high connectivity for terrestrial mammals with a large dispersion value and home range when compared with other categories of mammals. Furthermore, results evidence that the connectivity objective of the Natura 2000 network is not totally fulfilled, especially for protected forest surfaces, requiring the focus of future activities on increasing the connectivity of the network.

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