Well-connected living spaces for both animals and humans: unravelling complex interactions in coupled habitat and settlement networks

As much as many animal species depend on networks of well-connected habitat patches (i.e. habitat networks) for their long-term survival, many human societies are also dependent on networks of settlements that are well-connected by roads and traffic (i.e. settlement networks). In human-dominated landscapes, however, changes to any part of the settlement network can negatively affect the integrity of habitat networks, by causing decreases in habitat size, quality and/or connectivity. Interactions between these networks are often complex. For example, urban expansion can directly affect habitat sizes or connectivity, but can also have an indirect effect by causing changes in traffic flows. Nevertheless, understanding these interactions is essential for planning sustainable landscapes that maximise well-being and survivability for both animals and humans. Here we present the latest results of our research aimed at unravelling the complex interactions in coupled habitat and settlement networks. First we present results from a simulation study in which we assessed the effect of settlement and road network configurations on habitat connectivity. In general, we found a negative correlation between the number of settlements and habitat connectivity. Surprisingly, when comparing road networks with few and many roads, we also found that those with few roads did not always result in the highest habitat connectivity. Second we present the conceptual model and first results from the CHECNET project (Coupling human and ecological networks for sustainable landscape and transport planning), in which we aim to model the dynamics between empirically derived settlement and habitat networks in the Swiss plateau. The habitat networks are obtained from species occurrence data by combining habitat suitability modelling with habitat connectivity modelling. Dynamics in the settlement networks are simulated with the Swiss-wide land-use transport interaction model FaLC (Bodenmann et al. 2014). We present several interactions and feedbacks that we found in these networks and an outlook for future research in the CHECNET project. Based on our results, we emphasise the importance of considering complete habitat and settlement networks and their interactions for landscape-scale conservation planning.