B0965
Title: Joint species distribution modeling with competition for space
Authors: Juho Kettunen - University of Eastern Finland (Finland) [presenting]
Lauri Mehtatalo - Natural Resources Institute Finland (Finland)
Eeva-Stiina Tuittila - University of Eastern Finland (Finland)
Aino Korrensalo - Natural Resources Institute Finland (Finland)
Jarno Vanhatalo - University of Helsinki (Finland)
Abstract: Joint species distribution models (JSDM) are important statistical tools in community ecology. They are routinely used for inference and various prediction tasks, such as to build species distribution maps. However, existing JSDMs cannot model mutual exclusion between species. The deficiency is tackled in the context of modeling plant percentage cover data, where mutual exclusion arises from limited growing space and competition for light. A Bayesian hierarchical joint species distribution model is proposed where latent Gaussian variable models describe species niche preferences and Dirichlet-Multinomial distribution models the observation process and competition between species. Decision-theoretic model is used for comparison and validation methods to assess the goodness of the proposed model and its alternatives. The model is demonstrated by analysing the vegetation cover of an extensively studied boreal minerotrophic fen, which is part of the Siikaneva peatland study site in Southern Finland. The results improve the total vegetation cover estimates compared to the existing species distribution models and provide quantitative uncertainty estimates for them for the first time. The results also demonstrate that the proposed joint species distribution model can be used to simultaneously infer interspecific correlations in niche preference as well as mutual competition for space and through that provide novel insight into ecological research.