Planning priority conservation areas for biodiversity under climate change in topographically complex areas: A case study in Sichuan province, China

change. First, a topographic complexity could offer a high diversity of climatic conditions, resulting in more possibilities for adaptation [47]. Second, specific topography can change local atmospheric circulation to mitigate climate change [48]. Finally, as for the study area, the field survey showed that the topographic complexity provided shelters for biodiversity in the Quaternary Ice Age, such as the Hengduan Mountains [49, 50]. Although topographic complexity could significantly contribute to enhancing adaptation to cli- mate change, explicit quantification that was required highlighted changes in the effect of topogra- phy with temperature. In one such method, the effect of topographic complexity on adaptation was calculated by Rao’s quadratic entropy [51]. Another approach established the relationship between topographic positions and biodiversity to describe the mechanism of adaptation for cli- mate change [52]. Rather than measuring the topographic variation, our approach is different in its focus on quantifying the effect of topography on existing similar climatic conditions in a fixed area. According to our results, topographic complexity in a fixed window can provide more effec- tive shelters for biodiversity below 1.2˚C of temperature increase, where the index of topography position diversity is about 6 in Sichuan province. The quantifying results showed that the effect of topographic complexity would decrease or even be ignored with the temperature increase. Additionally, identifying suitable climatic areas for adaptation to climate change might be

useful, which have been used to plan ecological infrastructure for climate change. Nuñez Fig 7. Boxplots showing median, quartiles (25–75%), minimum and maximum of protection area for all national protection species in current nature reserves (a), in priority conservation areas for 2011–2040 (b), and 2031–2060 (c). https://doi.org/10.1371/journal.pone.0243425.g007 PLOS ONE Planning priority conservation areas for biodiversity under climate change in topographically complex areas PLOS ONE | https://doi.org/10.1371/journal.pone.0243425 December 23, 2020 11 / 15