A list of tools (GRASS GIS addons) I have created or contributed to. For installation you should preferably use the extension manager (g.extention or via GUI). If that doesn’t work, see the download link (and see here for installation instructions). For the full list of addons available for GRASS GIS, see here.
Computes the multivariate environmental bias, which compares the medium environmental conditions in an area (e.g., a country) to those in a subset of that area N (e.g., the protected areas in that country). It thus provides a measure to estimate how well conditions in the subset of an area represents conditions in the whole area (or the other way around, how biased the distribution of the subset is in environmental space. [manual page] [download link]
Detection and quantification of novel uni- and multivariate environments, following methods developed by Mesgaran et al. (2014). This includes areas where conditions fall outside the range of values observed in the reference / callibration data set (Type 1 novelty) or areas with novel combinations between the environmental variables (Type 2 novelty). [manual page] [download link]
Computes diversity indices based on 2 or more input layers representing species (or other categories being used). Indices currently implemented are the Renyi entropy index and a number of specialized cases of the Renyi enthropy, viz.the species richness, the Shannon index, the Shannon based effective number of species (ENS), the Simpson index (inverse and gini variants), and pielou’s eveness [manual page] [download link]
The function computes two metrics to quantify niche similarity or overlap between all pairs of input raster layers: (D) the niche equivalency or similarity for two species following Warren et al. (2009) based on Schoeners D (Schoener, 1968). [manual page] [download link]
Function to compute the variance inflation factor (VIF) and the square root of the VIF. The variable with the highest VIF will be dropped and the VIF will be recomputed. This will be repeated till an user-defined VIF threshold value is reached. [manual page] [download link]
Generates a raster layer with a weighted random selection of the raster cells (selected cells are assigned a value 1, other a value 0) based on a user defined weight raster layer. [manual page] [download]
Addon to create a forest fragmentation index from a GRASS raster map based on a method developed by Riitters et. al (2000). The index is computed using an moving window of user-defined size (default = 3). [manual page] [download]