Connectivity as the Amount of Reachable Habitat: Conservation Priorities and the Roles of Habitat Patches in Landscape Networks
Landscape connectivity plays an important role in sustaining ecological processes at different spatial and temporal scales (e.g., Connectivity conservation, Cambridge, 2006). Landscape connectivity can help to counteract some of the adverse effects of habitat fragmentation and to facilitate species range shifts in response to climate change. Therefore, maintaining or enhancing landscape connectivity is a key part of current biodiversity conservation efforts. A variety of metrics for analyzing connectivity have been developed, ranging from some derived from or used within metapopulation models (Nature 404:755–758, 2000; Ecology 84:1131–1145, 2002) to others based on network analysis (graph theory) (Community Ecol 1:89–94, 2000; Ecology 82:1205–1218, 2001; Ecol Appl 18:1810–1825, 2008; Ecography 33:523–537, 2010; Biol Conserv 144:44–55, 2011; Ecology 92:847–858, 2011). In particular, graph-based approaches have gained increasing popularity in ecological research and applied conservation planning in recent years (Front Ecol Environ 2:529–536, 2004; Landsc Urban Plan 83:91–103, 2007; Ecol Lett 12:260–273, 2009; Landsc Urban Plan 100:67–76, 2011; Landsc Ecol 27:185–198, 2012; Funct Ecol 28:990–998, 2014). Graphs are just a data structure, and, similarly to vector or raster data structures in geographical information systems, different outcomes of variable quality can be obtained through their use. A crucial issue is how to measure and analyze connectivity in order to capture important aspects and provide meaningful guidance for conservation decisions. Through this lab, students will.
KeywordsHabitat Patch Habitat Area Landscape Connectivity Connectivity Metrics Focal Patch
Funding was provided by the Spanish Ministry of Science and Innovation through DECOFOR (AGL2009–07140) and GEFOUR (AGL2012-31099) projects. The capercaillie habitat data were provided by Instituto Catalán de Ornitología (ICO) with support from Generalitat de Catalunya (Departament d’Agricultura, Ramaderia, Pesca, Alimentació i Medi Natural) and CatalunyaCaixa (Obra Social). We thank all volunteers that made possible the collection of the information for the Catalan Breeding Bird Atlas.
References and Recommended Readings1
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