How different climate change and land use scenarios affects microorganisms diversity and freshwater ecosystem functioning: a mesocosms experiment

• Grant number: 24/17069-8
• Support Opportunities: Scholarships in Brazil - Master
• Start date: January 01, 2025
• End date: February 28, 2026
• Field of knowledge: Biological Sciences - Ecology - Ecosystems Ecology
• Principal Investigator: Gustavo Quevedo Romero
• Grantee: Marcela Lamas Cosenza
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 19/08474-8 - Freshwater ecosystems under climate change: impacts across multiple levels of organisation, AP.PFPMCG.TEM
• Associated scholarship(s): 25/04986-5 - Assessing freshwater fungi productivity and community composition to understand leaf litter decomposition rates in a mesocosm experiment, BE.EP.MS

Abstract

Climate change (e.g., warming), along with land use (e.g., deforestation and agriculture), can affect decomposers' community structure in freshwaters, including fungi known as aquatic hyphomycetes (AHs). It is expected that biodiversity changes in fungi communities can accelerate the rates of leaf litter decomposition, an essential function for maintaining freshwater ecosystems. However, there is a lack of knowledge concerning how multiple anthropogenic stressors can affect the biodiversity-ecosystem functioning relationship on the decomposition process. Regarding this matter, the project proposes to investigate how climate and land use change can affect fungi communities, approaching diversity and biomass accrual parameters, as well as the consequences for the decomposition process in freshwaters. Temperature and nutrient manipulations were carried out in a mesocosm experiment, allowing us to investigate how warming and nutrient supply affect the microorganisms. The mesocosms received a randomized treatment combining temperature increase, reduction in the allochthonous detritus supply, and nitrogen and phosphorus addition simulating climate change and land use scenarios (predicted for 2100). The material collected from the mesocosms will be used for the sequencing of the 18S rRNA gene and the fungi spore identification to access the biodiversity of the microbial community. To measure the decomposition rates, the dry detritus biomass and the cellulose decomposition will be used as proxies.