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bioRxiv · 10.1101/2024.05.31.596814

Higher functional resilience of temperate forests at intermediate latitudes of a large latitudinal gradient in South America

Abstract

Accurately mapping and assessing plant functional composition across space and time is pivotal for understanding environmental change impacts on the biodiversity and functioning of forests. Here, we test the capabilities of a combination of in-situ and remote sensing approaches to deliver accurate estimates of the functional composition of temperate forest ecosystems considering leaf and stem morphological, nutrient, hydraulic, and photosynthetic traits. We identify hydrological stress, soil, and topography as key drivers of plant functional traits. Further, hydrological stress and soil are key determinants of functional dispersion and redundancy in temperate forests distributed across a large latitudinal (30{degrees}S to 53{degrees}S) gradient in Chile. Functional dispersion peaks across Mediterranean forests, woodlands, and scrub, occupying between 30{degrees}S to 35{degrees}S. Conversely, functional redundancy peaks between 42{degrees}S and 53{degrees}S, corresponding to Magellanic subpolar forests. Although functional dispersion and redundancy peak at different latitudes corresponding to distinct forest types; they are both high at latitudes between 35{degrees}S and 42{degrees}S, coinciding with Valdivian temperate rainforests. Our results highlight areas in temperate forests in South America where both tree functional dispersion and redundancy are high, and hence could potentially be more resilient to environmental changes.

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BibTeXRIS

Deng, X., Carvajal, D. E., Urrutia-Jalabert, R., Machida, W. S., Rosen, A., Zhang-Zheng, H., Galbraith, D., Diaz, S., Malhi, Y., Aguirre-Gutierrez, J.. 2024-06-03. Higher functional resilience of temperate forests at intermediate latitudes of a large latitudinal gradient in South America. https://doi.org/10.1101/2024.05.31.596814

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