Efficient synthetic generation of ecological data with preset spatial association of individuals

Abstract

Many experiments are not feasible to be conducted as factorials. Simulations using synthetically generated data are viable alternatives to such factorial experiments. The main objective of the present research is to develop a methodology and a platform to synthetically generate spatially explicit forest ecosystems represented by points with a predefined spatial pattern. Using algorithms with polynomial complexity and parameters that control the number of clusters, the degree of clusterization, and the proportion of nonrandom trees, we show that spatially explicit forest ecosystems can be generated time efficiently, which enable large factorial simulations. The proposed method was tested on 1200 synthetically generated forest stands, each of 25 ha, using 10 spatial indices: Clark-Evans aggregation index, Ripley’s K, Besag’s L, Morisita’s dispersion index, Greig-Smith index, the size dominance index of Hui, index of nonrandomness of Pielou, directional index and mean directional index of Corral-Rivas, and size differentiation index of Von Gadow. The size of individual trees was randomly generated aiming at variograms like real forests. We obtained forest stands with the expected spatial arrangement and distribution of sizes in less than one hour. To ensure replicability of the study we have provided a free fully functional software that executes the stated tasks.