Shedding Light on Trophic Cascades: How Sunlight Can Shape Small, Freshwater Ecosystems
Date
2-18-2025
Faculty Mentor
Grover Brown, Biology
Files
Submission Type
Conference Proceeding
Location
11:00-11:10 am | Houston Cole Library, 11th Floor
Description
Please note: no video is available for this presentation.
Trophic cascades play a critical role in ecosystem dynamics, influencing nutrient cycling and biomass distribution. This study investigates a bottom-up trophic cascade in Hanes Branch Stream, Jacksonville, Alabama, by examining how increased sunlight, a limiting resource in small streams, impacts freshwater food webs. We analyzed algae biomass, snail density, macroinvertebrates, and fish populations in sunlit (upstream) and shaded (downstream) sections. Our results showed a significant increase in snail density upstream, suggesting greater primary production fueled by enhanced sunlight exposure. However, a sewage spill in July 2024 dramatically disrupted this balance, leading to a severe decline in snail populations compared to pre-spill data from 2023. Most snails observed post-spill were deceased, which could have a cascading effect at higher trophic levels. Understanding these interactions is crucial for preserving biodiversity and maintaining ecosystem stability in our city.
Keywords
student research, biology
Rights
This content is the property of Jacksonville State University and is intended for non-commercial use. Video and images may be copied for personal use, research, teaching or any "fair use" as defined by copyright law. Users are asked to acknowledge Jacksonville State University. For more information, please contact digitalcommons@jsu.edu.
Disciplines
Biology
Recommended Citation
James, Chloe, "Shedding Light on Trophic Cascades: How Sunlight Can Shape Small, Freshwater Ecosystems" (2025). JSU Student Symposium 2025. 67.
https://digitalcommons.jsu.edu/ce_jsustudentsymp_2025/67
