Figure 1.
Study area and spatial distribution of Afzelia africana and Pterocarpus erinaceus in Benin.
Table 1.
Environmental variables used and their sources.
| Bioclimatic/biophysical variables | Description | Contribution of predictor variables to the model for each species | Resolution | Sources | |
|---|---|---|---|---|---|
| Afzelia africana | Pterocarpus erinaceus | ||||
| Bio_2 | Mean diurnal range (max temp - min temp) (monthly average) | X | X | ||
| Bio_4 | Seasonal temperature variation | X | X | 2,5 min | (Fick & Hijmans, 2017) |
| Bio_5 | Max temperature of warmest period | X | |||
| Bio.12 | Annual precipitation | X | X | ||
| Soil (biophysical v.) | Global soil types | X | X | ~0,54 min | (GLCF, 2023) |
Table 2.
Relative contributions of the environmental variables to the model of each species (Percent contribution).
| Species | Mean diurnal range (bio_2) | Seasonal temperature variation (bio_4) | Annual precipitation (bio_l2) | Max temperature of warmest month (bio_5) | Types of soil (soil) |
|---|---|---|---|---|---|
| A. africana | 25.3% | 9.4% | 18.7% | - | 46.4% |
| P. erinaceus | 19.7% | 4.3% | 20.3% | 4.3% | 51.4% |
Figure 2.
Results of the Jackknife test using AUC on test data.
Table 3.
Evaluation of the potential habitat suitability area for the species studied in Benin under current and future climatic conditions (HadGEM2-ES, MIROC5, RCP4.5 and RCP8.5).
| Species | RCP | Models | Unsuitable | Low suitability | Medium suitability | High suitability | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Areas (km2) | Trends (%) | Areas (km2) | Trends (%) | Areas (km2) | Trends (%] | Areas (km2) | Trends (%) | |||
| A. africana | Current | 9638.82 | 15098.71 | 27488.52 | 62536.93 | |||||
| RCP4.5 | HadGEM2-ES | 10252.29 | 0.5 | 13537.21 | -1.3 | 43080.59 | 13 | 47892.89 | -12 | |
| MIR0C5 | 9582.75 | -0.04 | 12449.20 | -2 | 45089.21 | 15 | 47641.82 | -12 | ||
| RCP8.5 | HadGEM2-ES | 8578.44 | -0.9 | 17428.91 | 2 | 50194.44 | 19 | 38561.2 | -20 | |
| MIROC5 | 7239.37 | -2 | 21990.129 | 6 | 54860.27 | 23 | 30673.22 | -27 | ||
| P. erinaceus | Current | 16363.17 | 9745.70 | 22800.20 | 65853.92 | |||||
| RCP4.5 | HadGEM2-ES | 13704.58 | 2 | 9708.29 | -0.3 | 29522.45 | 5 | 61827.66 | -3 | |
| MIROC5 | 13892.9 | -2 | 7155.67 | -2 | 23266.45 | 0.4 | 70447.96 | 4 | ||
| RCP8.5 | HadGEM2-ES | 13495.36 | -2 | 15755.06 | 5 | 32807.37 | 8 | 52705.19 | -11 | |
| MIROC5 | 13704.59 | 2 | 4561.21 | -4 | 39963.05 | 14.9 | 56534.13 | -8 | ||
Figure 3.
Predicted habitat suitability for Afzelia africana in Benin under current and future climate scenarios: (a) Current conditions, (b) MIROC5 RCP4.5, (c) MIROC5 RCP8.5, (d) HadGEM2-ES RCP4.5, and (e) HadGEM2-ES RCP8.5.
Figure 4.
Predicted habitat suitability for Pterocarpus erinaceus in Benin under current and future climate scenarios: (a) Current conditions, (b) MIROC5 RCP4.5, (c) MIROC5 RCP8.5, (d) HadGEM2-ES RCP4.5, and (e) HadGEM2-ES RCP8.5.