Sharing research on tropical Andean forests at EGU26 in Vienna!

By Andrea Chávez

I presented my research poster at the EGU 2026, held in Vienna, Austria, from 3–8 May. My contribution, “Water Use Efficiency under fertilization schemes in an elevational gradient – Preliminary results from Nutrient Manipulation Experiment in Ecuador”, explored how nutrient availability and elevation shape the physiological responses of tropical montane trees in southern Ecuador.

Tropical montane forests are biodiversity hotspots that play an important role in global carbon and water cycles. As atmospheric CO₂ concentrations rise and nitrogen (N) and phosphorus (P) inputs change, understanding how trees respond to these environmental pressures becomes increasingly important.

Thus, my research aims to answer how do tropical trees maintain their carbon–water balance as nutrient availability changes? For this, I measured intrinsic water-use efficiency (iWUE), a physiological indicator of the relationship between carbon assimilation and stomatal conductance. Using stable carbon isotopes (δ¹³C), we investigated whether long-term nutrient enrichment alters tree water-use strategies and how these responses vary along an elevation gradient in the experiment. We studied six tree species across three elevations (1,000, 2,000 and 3,000 m above sea level) within the long-term Nutrient Manipulation Experiment (NUMEX) in the Ecuadorian Andes. I am working on the manuscript but you can read the abstract here https://meetingorganizer.copernicus.org/EGU26/EGU26-19064.html

I look forward to continuing to explore how tropical Andean forests respond to environmental change and what these responses can teach us about the future of these remarkable ecosystems. Lastly, EGU General Assembly 2026 was an opportunity to exchange ideas, discuss scientific approaches and connect with researchers working on environmental change and ecosystem functioning.