FUNCTIONAL CONECTIVITY AND THE IMPORTANCE OF THE LANDSCAPE-ORGANISM INTERACTION
Keywords:Habitat fragmentation, dispersal, perceptual range, graph theory
The effects that changes on landscape spatial patterns have on ecological processes are of great importance due to the increasing rate of human modifications on the landscape, such as habitat fragmentation and habitat loss. Landscape connectivity, the opposite of fragmentation, determines the degree to which a landscape facilitates or restricts the movement of organisms between habitat patches. It influences population survivorship and dynamics on fragmented landscapes. With the development of Landscape Ecology, different indices for estimating landscape connectivity appeared. Some indices were criticized because of their redundancy, sensibility to scale, and because they measured only physical aspects of the landscape. Several authors have called attention on the importance of considering organism-landscape interactions when studying connectivity. There is a difference between structural connectivity, which considers only physical aspects of the landscape, and functional connectivity, which considers species-landscape interactions. Functional connectivity is a variable dependent on the vagility of the organism. Research priorities should focus on studying species-specific behavioral aspects, and making a link between these traits and landscape connectivity. Graph theory appears as a useful tool for studying functional connectivity. It allows for the use of species specific traits, and it helps on decision making for increasing landscape connectivity.