Freshwater ecosystems such as lakes, ponds, and wetlands release large amounts of methane, a greenhouse gas much more powerful than carbon dioxide. As these ecosystems face increasing pressures from climate warming and nutrient pollution, understanding what controls methane emissions has become essential for improving climate predictions and developing effective management strategies.
Therefore, in this thesis, I investigated how warming, nutrient inputs, aquatic plants, and animals inhabiting the sediment (bioturbators) influence methane production, consumption, and release from freshwater sediments. My research showed that reductions in nutrient inputs and long-term warming change the communities of microorganisms responsible for methane consumption, but these changes do not always reduce methane emissions. The results also demonstrated that aquatic plants and bioturbating worms can either increase or decrease methane emissions depending on their characteristics and the type of sediment in which they live. In addition, a new scanning method was developed to measure methane stored as gas bubbles in sediments, improving estimates of an important but often overlooked emission pathway. Together, these findings show that methane emissions are controlled by a complex interaction of biological and local environmental factors. Effective mitigation therefore requires integrated and site-specific management strategies.
Ilenia Marquina Luévano is a microbiologist and environmental scientist with expertise in laboratory research, data analysis, and microbial ecology. She obtained her Bachelor's degree in Chemistry, Bacteriology and Parasitology (Microbiology) from the Universidad Autónoma de Nuevo León, México, and worked in the food industry as a microbial laboratory analyst and quality inspector. Awarded the Orange Tulip Scholarship, she completed an MSc in Biology at Radboud University, conducting research at both Radboud University and the Netherlands Institute of Ecology (NIOO-KNAW). She subsequently earned her PhD in Ecology at Radboud University, investigating the biological drivers of methane emissions in freshwater ecosystems. During her PhD, she supervised students, presented her work at international conferences, and submitted her work to peer-reviewed journals. She is now seeking opportunities in the Dutch industry or in academic support roles, where she can apply her laboratory, analytical, or project coordination skills in collaborative scientific environments.