Potential effects of climate change on members of the Palaeotropical pitcher plant family Nepenthaceae.

Laura K Gray,Charles Clarke,G R William Wint,Jonathan A Moran

doi:10.1371/journal.pone.0183132

Abstract

Anthropogenic climate change is predicted to have profound effects on species distributions over the coming decades. In this paper, we used maximum entropy modelling (Maxent) to estimate the effects of projected changes in climate on extent of climatically-suitable habitat for two Nepenthes pitcher plant species in Borneo. The model results predicted an increase in area of climatically-suitable habitat for the lowland species Nepenthes rafflesiana by 2100; in contrast, the highland species Nepenthes tentaculata was predicted to undergo significant loss of climatically-suitable habitat over the same period. Based on the results of the models, we recommend that research be undertaken into practical mitigation strategies, as approximately two-thirds of Nepenthes are restricted to montane habitats. Highland species with narrow elevational ranges will be at particularly high risk, and investigation into possible mitigation strategies should be focused on them.

Highlights

The monotypic Palaeotropical family Nepenthaceae is the largest family of pitcher plants, comprising approximately 140 species
The area under the curve (AUC) value is a measure of model accuracy, where, for instance, a value of 0.88 indicates that 88% of the time a random sample from presence predictions will have a greater probability of presence than a random selection from absence predictions across all available probability thresholds
N. tentaculata shows a higher model accuracy than N. rafflesiana (Table 1). These results are likely to be related to the more limited range of the former, which is a highland species: many studies have found that species distribution models for species with smaller ranges or narrower ecological tolerances have higher prediction accuracy than models developed for more widespread species [36,37,38,39]. These studies conclude that the higher predictive accuracy is a result of the fact that it is easier to separate suitable from unsuitable habitat for species with restricted environmental tolerances or very specific habitat requirements

Summary

Introduction

The monotypic Palaeotropical family Nepenthaceae (genus Nepenthes) is the largest family of pitcher plants, comprising approximately 140 species. The majority of Nepenthes species fall into two rather broad groupings, defined largely by their altitudinal distributions: so-called "lowland" species occur in habitats ranging from 0 m to approximately 1100 m above sea level (asl), whereas "highland" species are restricted to cooler, montane habitats, usually above 1100 m asl [2,3]. Beyond these two major groups, a few species occupy intermediate altitudinal ranges from approximately 700 to 1400 m asl; in addition, some species can occasionally be found growing above or below their typical altitudinal thresholds.

Methods

Results

Discussion

Conclusion