Complex network analysis of socio-ecological systems

Complex network theory and analysis (CNTA) belong to a stream of research studies refuelled by the interplay between the extensive use of statistical mechanics tools based on a re-interpretation of the well-known graph theory and the availability of a huge processing power accessible today in unprecedented ways. At the turn of the millennium, a multi-sector community of scientists began to apply CNTA to the scrutiny of large systems with the lenses of network modelling. The underlined assumption is that any system can be conceived of as an ensemble of punctual elements, to be represented by nodes, intertwined through a set of connections, sketched as edges. A major advantage of CNTA is the use of very simple metrics able to picture the general and local properties of the network and the ability to classify the different systems into classes of webs. In this essay, I demonstrate how CNTA can be applied to a category of systems, i.e. socio-ecological ensembles, where network elements and general properties are designed to describe phenomena considered in both social sciences and ecology. Typically, I study commuting and ecological networks. In the first case, the nodes stand for origin and destination towns of the daily movement and the edges for the commuting relation between the towns. In the second case, the nodes stand for habitat patches of certain vegetal target species and the edges for the seed dispersal relation between the patches. Results demonstrate how CNTA is able to discover common properties even in apparently different systems.