el-Sur - ELevation-diversity relationships along a latitudinal gradient in southern SoUth AmeRica

• Applicant: Professor Dr. Severin Irl
• Subject Area: Physical Geography ; Ecology and Biodiversity of Plants and Ecosystems
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 537131975

Understanding the drivers of diversity patterns is a fundamental task in biogeography, particularly in our rapidly changing world that is currently facing dramatic biodiversity loss. Large-scale plant biodiversity patterns are proposed to be driven by climate, area and evolutionary history. Even though elevation-diversity relationships have drawn the attention of biogeographers and ecologists since Alexander von Humboldt’s times, it is still unclear, as a result of their collinearity, what the individual effects of these drivers are. The el-Sur project aims to disentangle the multilayered processes operating across scales that generate and maintain biodiversity. To achieve this, we leverage a unique study system, the Andes of southern South America that are considered a global biodiversity hotspot, to study how elevation-diversity relationships are affected by climate, area and evolutionary history. We have identified a suite of highly suitable elevational gradients along the Chilean Andes ranging from the Mediterranean winter rain biome in Central Chile to the Valdivian rainforest and the Magellanic rainforest in the South. El-Sur is a collaboration of Severin Irl from the Goethe-University Frankfurt with Dylan Craven from the Universidad Mayor in Santiago de Chile. The 36-month project will focus on three main objectives that divide the project into three work packages (WPs). WP1 will quantify how elevation-diversity relationships change with latitude and area using taxonomic and phylogenetic diversity measures. WP2 will disentangle the effect of water availability and aridity from temperature effects by using paired elevational gradients on the windward and leeward side of the Andes. WP3 will study macroevolutionary diversity patterns along elevation and aridity gradients to test several competing evolutionary theories (Out-of-the-tropics hypothesis, tropical niche conservatism and austral niche conservatism) using the anomaly that many species are of Gondwana origin in southern South America. Within El-Sur, we will conduct extensive field work in Chile to sample multiple elevational gradients on the windward and leeward side of the Andes. We will combine sampling woody vegetation using vegetation plots with state-of-the-art phylogenetic and bioclimatic data as well as species distribution modelling and macroecological analyses. El-Sur will lead to a more mechanistic understanding of the underlying processes driving plant diversity across spatial scales as well as along multiple environmental gradients using a unique, but historically underrepresented model system of the Global South.

• DFG Programme: Research Grants