Dataset: Shifts in distribution ranges of Mexican oaks due to climate change and their consequences on the geographical patterns of species richness

This repository contains the files associated with the following article:

Nathalie S. Hernández-Quiroz and E.I. Badano “Shifts in distribution ranges of Mexican oaks due to climate change and their consequences on the geographical patterns of species richness”, submitted to Plant Diversity.

Dataset 01 is a compressed file (*.rar) that compilates a series of Microsoft Excel files with data that supports the results of the study (104 files, a file per oak species). Each Excel file contains three spreadsheets. The first one has the occurrence data (latitude and longitude) used to calibrate the distribution model of the corresponding species (SDM), the near-to-present values of the 19 bioclimatic variables associated with these coordinates, and the Spearman correlation coefficients used to select the variables included in the SDM (selected variables are indicated in green). The second spreadsheet shows the near-to-present occurrence probabilities of the target species that concur with its presence data, and the table on the side shows the fraction of true presences dropping at each probability decile. The third spreadsheet shows ten-thousand random geographic coordinates and their corresponding near-to-present and future occurrence probabilities of the species. Future occurrence probabilities are provided for the three CMIP6 models used in the study (CanESM5, MIROC6 and INM-CM4-8) at four radiative forcing levels estimated by the middle of the 21st century (2.6, 4.5, 7.0 and 8.5 W/m2).

Dataset 02 is comprised by a series of interactive maps optimized for Google Earth. To visualize these maps, we recommend installing the latest desktop version of this software. Opening this file may take several minutes, depending on the speed of the CPU, the available Random-Access Memory (RAM) and the Video Random Access Memory (VRAM). The interactive maps are organized in the different folders and detailed information on model outputs can be accessed expanding them (click on the arrow on the left of folders to expand them):

Major mountain ranges of Mexico – This folder contain the polygons of the major mountain ranges of Mexico, which are the regions estimated to contain most oak species.

Estimated species distributions – For each Mexican oak, this folder shows the distribution of georeferenced records used to calibrate its SDM. The folder also contains the estimated distribution ranges of the species (pixels with occurrence probability is higher than 0.5) under the near-to-present and future climate (red layers). The surface area of distribution ranges (in km2) can be visualized clicking on the corresponding layer. The mid-century distribution ranges of species are provided separately following the predictions of the three CMIP6 models used in the study (CanESM5, MIROC6 and INM-CM4-8) at four radiative forcing levels each (2.6, 4.5, 7.0 and 8.5 W/m2), and these layers are accompanied with the corresponding distribution of areas classified as climatically unsuitable in the MESS analyses (white layers). Clicking on the scientific name of each species displays a message indicating the bioclimatic variables used to calibrate the SDM, the percent variance explained by each of them and the average AUC value of the model. This message also shows the statistical results supporting the relationships between near-to-present and future occurrence probabilities, which are accompanied with the corresponding graphs. These graphs are provided for the different radiative forcing levels, where the black line is the theoretical relationship with intercept = 0 and slope = 1, while lines in other colours are the empirical relationships obtained for the predictions of CanESM5 (red line), MIROC6 (Green line) and INM-CM4-8 (yellow line).

Shifts in oak richness – This folder contains interactive maps showing the current and future richness patterns of oaks across Mexico. These maps are organized in subfolders for the near-to-present climate and the climate predicted to occur by the middle of the 21st century by the three CMIP6 models used in the study (CanESM5, MIROC6 and INM-CM4-8) at four radiative forcing levels each (2.6, 4.5, 7.0 and 8.5 W/m2). For building these maps, Mexico was subdivided using a 1:50000 UTM-scaled grid comprised by 2312 spatial units of 27.7 x 32.5 km (~900 km2 each), and oak richness at each grid cell was estimated counting the number of species overlapping their distribution ranges within it. To simplify the visualization of this information, spatial units of the grid were classified in species richness categories that increase every ten units (see the reference scale of maps). Clicking on each spatial unit (grid cells) displays the full list of oaks included in the study, and those species dropping within the spatial unit are indicated with a “X” symbol.