SILand: an R package for estimating the spatial influence of landscape

Abstract

ContextThe spatial distributions of species and populations are both influenced by local variables and by characteristics of surrounding landscapes. Understanding how landscape features spatially structure the frequency of a trait in a population, the abundance of a species or the species richness remains difficult specially because the spatial scale effects of the landscape variables are often unknown. ObjectivesHere, we present "siland", an R package for analyzing the effect of landscape features on georeferenced point observations (described in a Geographic Information System shapefile format). Methods & Results"siland" simultaneously estimates the spatial scales and intensities of landscape variable effects. It does not require any information about the scale of effect. Two methods are available: one is based on focal sample site (Bsiland method, b for buffer) and one is distance weighted using Spatial Influence Function (Fsiland method, f for function). siland allows for effects tests, effects maps and models comparison. ConclusionsAdaptable and user-friendly, the "siland" package is a very practical tool to perform landscape analysis.