The effect of large mammal herbivores on soil nematodes in tropical forests

• Grant number: 25/03637-7
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: August 01, 2025
• End date: July 31, 2026
• Field of knowledge: Biological Sciences - Ecology - Ecosystems Ecology
• Principal Investigator: Mauro Galetti Rodrigues
• Grantee: Letícia Gonçalves Ribeiro
• Supervisor: Elizabeth Le Roux
• Host Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil
• Institution abroad: Aarhus University, Denmark
• Associated to the scholarship: 23/12828-5 - Linking the brown and green world: The effects of large herbivores on soil properties in a tropical forest, BP.DR

Abstract

This project aims to investigate the impact of large mammalian herbivores (LMHs) on soil nematode communities in a tropical forest ecosystem. LMHs play a crucial role in shaping soil properties. Through herbivory, they can alter litter quality and quantity, as well as nutrient inputs to the soil. In addition, they cause physical disturbance through trampling and supply nutrients through dung and urine inputs. They also affect microbial communities and other soil organisms. Nematodes, which occupy multiple trophic levels and contribute significantly to nutrient cycling, are valuable indicators of soil ecosystem health. While studies in temperate forests have shown that LMHs can alter litter quality, microbial composition, and nematode community structure, the specific effects of LMHs on soil biota in tropical forests remain underexplored. Therefore, this study aims to investigate the effects of LMHs on soil nematode communities in a tropical forest using a long-term (14 years) mammal exclusion experiment in the Brazilian Atlantic Forest. Soil samples will be collected from paired open and fenced plots and analyzed for chemical, physical and biological properties and for nematode extraction. Nematodes will be identified, classified into functional groups and evaluated using ecological indices. This research will involve the application of models to assess how LMH biomass and soil properties affect nematode abundance, diversity, and ecological indices. This comparison will help assess the impact of LMHs on nutrient cycling through above and belowground interactions.