Predicting suitable habitats of Podophyllum hexandrum under a climate change scenario in Nepal

Podophyllum hexandrum Royle is a perennial herb with high medicinal significance. Due to high demand, rhizomes are being harvested unsustainably. Besides, climate change has become another prevalent threat to its population. In Nepal, the information on the suitable habitats of Podophyllum hexandrum is inadequate. Therefore, the present study modelled suitable habitats of Podophyllum hexandrum under current and future climate change scenarios using MaxEnt probabilistic modelling. Nine bioclimatic and two topographic variables with 36 occurrences of Podophyllum hexandrum were used in the model. Furthermore, response curves for each selected predictor variable were generated, and a jackknife test was conducted to estimate the effect of individual predictors on habitat suitability. The model output indicated that about 24.36% of Nepal’s total area was suitable for the occurrence of Podophyllum hexandrum. Out of the total current suitable area, 2.31% constitute high, 6.14% mid and 15.91% constitute low probability regions. The highest potential distribution was predicted in eastern and central Nepal, whereas the western region has low suitability under the current climatic scenario. In addition, the future suitability projection showed that the suitable range would decline in 2050 and 2070 under SSP-245 and SSP-585 trajectories, respectively. Altitude and precipitation seasonality (Bio 15) were the important environmental factors affecting the spatial distribution. Overall, this study identified potential habitats for Podophyllum hexandrum under current and future climatic scenarios in Nepal, providing a framework for its conservation planning and habitat management.