The current dataset is part of WP1 Task 1 "psychological restoration - visual scenes" and was collected between March and May 2021 in facilities of the German Centre of Integrative Biodiversity Research (iDiv). It consists of data from a picture sort paradigm where we asked a total of 48 participants to sort 57 pre-selected forest photographs depicting varying levels of tree species richness as well as alternating tree species compositions. With this study we aim to better understand the concept of perceived forest diversity. In detail we wish to obtain insights about visual cues that people use when being instructed to categorise photos with varying tree species richness levels.

A total of 48 subjects participated in this study. Participants had to sort 57 forest photographs depicting varying levels of tree species richness as well as altering tree species compositions. Photographs were taken in temeprate, natural forest in Germany (Hainich), Belgium (TREEWEB) and Poland (Bialowieza) in late summer 2020. The experiment consisted of two open sorts and one closed sort. In the open sorts, participants were instructed to sort the photos according to any similarity-based sorting criterion and subordinate categories they liked. In the closed sort forest biodiversity was the sorting criterion. Participants were asked to sort the photos accoring to low, medium and high forest biodiversity levels. The succession of open and closed sort was fixed to prevent spillover effects.

pictures were taken in August / September 2020; the study was conducted from March-May 2021

We aim to quantify how people preceive and categorize forest pictures that contain alternating levels of tree species richness. We do multidimensional scaling for the open sorts. For the closed sort, the mean of the preceived biodiveristy score was correlated with actual tree species richness depicted on the photos. Perceived forest biodiversity ratings will then be compared with actual visual diversity indices.