The potential impacts of climate change on the extent, distribution and functional diversity of the Montane-Specialist Tree Community in Mesoamerica

Abstract

Tropical montane forests (TMFs) are ecosystems that, despite their small global area, have rich biodiversity, provide essential ecosystem services, and are of cultural significance. Their restricted distribution makes them highly vulnerable to anthropogenic pressures, including climate change. Their high ecological variability in remote areas with complex terrain makes their study challenging and costly, which may impede the design and implementation of conservation measures to preserve their biota and functions. In Chapter 2, I systematically review and critically assess the research on global TMFs under ongoing climate change, revealing some important methodological, geographical, and thematic biases: trees are the most studied group, and the Neotropics is the most studied region. Although these biases should be overcome, they also constitute an opportunity to direct efforts within well-studied areas that could serve as proxies for analogous tropical montane regions while local research is underway. One such area of opportunity is the montane-specialist tree community in Mesoamerica. The Neotropics are a hotspot of montane biota and of rare and range-restricted species, yet there is a dearth of information on the impacts on the montane-specialist tree subcommunity of its forests. Given the disproportionate role that rare and range-restricted species play in terms of richness, functional diversity, and support of vulnerable ecosystem functions, it is critical to forecast their potential responses to climate change. In Chapter 3, I use species distribution modelling to project the range and distribution of 272 Mesoamerican montane-specialist tree species under current and future climatic conditions by the end of the century, showing that this subcommunity will undergo significant losses of suitable habitat, but with some relicts remaining even under a severe climate change scenario. In Chapter 4, I incorporate the modelling results into a functional trait analysis to identify spatial patterns of functional diversity throughout the Mesoamerican region, their potential carbon stock capacity in aboveground biomass, and how these are predicted to shift in response to climate change. I found that despite the projected losses in suitable habitat, the functional diversity and aboveground biomass spatial patterns will persist, although they will be less conspicuous. These findings highlight the contribution of the montane-specialist trees’ role in providing functional redundancy and stability to their communities and call for urgent action to complement existing conservation measures with active efforts such as seed banks and assisted migration programmes for montane-specialist trees globally. Overall, this thesis establishes a framework for future research and policy to protect montane-specialist trees in Mesoamerica, highlighting the need for integrated evidence, cross-disciplinary methods, and international collaboration to address climate change challenges.

More information

Identifiers

ORCID for Erik Omar Mata Guel: orcid.org/0000-0001-7760-154X

ORCID for Kelvin Peh: orcid.org/0000-0002-2921-1341

ORCID for Becky Morris: orcid.org/0000-0002-0020-5327

Catalogue record

Export record