Very high resolution Earth Observation features for testing the direct and indirect effects of landscape structure on local habitat quality

tModelling the empirical relationships between habitat quality and species distribution patterns is the firststep to understanding human impacts on biodiversity. It is important to build on this understanding todevelop a broader conceptual appreciation of the influence of surrounding landscape structure on localhabitat quality, across multiple spatial scales. Traditional models which report that ‘habitat amount’in the landscape is sufficient to explain patterns of biodiversity, irrespective of habitat configurationor spatial variation in habitat quality at edges, implicitly treat each unit of habitat as interchange-able and ignore the high degree of interdependence between spatial components of land-use change.Here, we test the contrasting hypothesis, that local habitat units are not interchangeable in their habitatattributes, but are instead dependent on variation in surrounding habitat structure at both patch- andlandscape levels. As the statistical approaches needed to implement such hierarchical causal models areobservation-intensive, we utilise very high resolution (VHR) Earth Observation (EO) images to rapidlygenerate fine-grained measures of habitat patch internal heterogeneities over large spatial extents. Weuse linear mixed-effects models to test whether these remotely-sensed proxies for habitat quality wereinfluenced by surrounding patch or landscape structure. The results demonstrate the significant influenceof surrounding patch and landscape context on local habitat quality. They further indicate that such aninfluence can be direct, when a landscape variable alone influences the habitat structure variable, and/orindirect when the landscape and patch attributes have a conjoined effect on the response variable. Weconclude that a substantial degree of interaction among spatial configuration effects is likely to be thenorm in determining the ecological consequences of habitat fragmentation, thus corroborating the notion of the spatial context dependence of habitat quality