Intraspecific morphological variation and environmental drivers in Macleania rupestris: a model-based population...

Area of Science:

• Ecology
• Plant Morphology
• Conservation Biology

Background:

• Macleania rupestris, an ecologically and culturally significant Ericaceae species in Ecuador's montane forests, displays considerable intraspecific morphological variation.
• Understanding this variation and its environmental drivers is vital for conservation and restoration planning, especially under climate change.

Purpose of the Study:

• To identify distinct morphological groups within Macleania rupestris populations.
• To assess the environmental drivers, including climatic seasonality and spatial autocorrelation, influencing these morphological traits.
• To develop a trait-based classification framework for conservation and restoration.

Main Methods:

• Analysis of 15 quantitative traits in 200 individuals from four populations in Azuay and Cañar provinces.
• Application of hierarchical clustering and Random Forest classification to identify morphological groups.
• Use of generalized linear models to evaluate the influence of climatic seasonality and spatial autocorrelation on key traits.

Main Results:

• Two distinct morphological groups were identified, primarily differing in seed number, fruit humidity, fruit dimensions, and petiole length, explaining over 75% of variation.
• Climatic seasonality and spatial autocorrelation significantly influenced key traits; seed number and fruit length showed strong responses to temperature and precipitation.
• A Random Forest model achieved 99.5% accuracy in assigning individuals to morphological groups based on key traits.

Conclusions:

• Environmental heterogeneity drives intraspecific differentiation and local adaptation in Macleania rupestris along climatic gradients.
• The study provides a novel trait-based classification framework, integrating morphological variation and environmental factors for effective conservation.
• Findings inform seed sourcing and restoration strategies to enhance ecosystem resilience in Ecuadorian montane forests.