Topic Modeling of Fatty Acid Studies: Evaluating Environmental Changes in Freshwater Ecosystems

Abstract

Fatty acids (FAs) are biochemical molecules with vital structural and metabolic functions in all living organisms. Over the last decades, FA analysis in ecological studies has garnered significant attention due to its diverse applicability, such as taxonomic support for species identification, investigations on trophic interactions, and environmental monitoring of aquatic ecosystems. Here, we reviewed the usage of FAs in ecological studies analyzing environmental changes in freshwater systems by applying a Topic Modelling Analysis to a total of 119 papers previously extracted by a systematic search in Web of Science, followed by ordination analyses. The analysis revealed topic similarities among publications and assessed topic popularity—hot, neutral, and cold topics—based on their prevalence over the years. Topics such as “Seasonality and land-use effects”, “Environmental/temperature stress in biofilms”, “Highly Unsaturated Fatty Acids (HUFAs) in plankton”, and “FAs in fish tissues” were classified as hot topics, with the first two experiencing an increasing trend since 2015. Topics classified as neutral included “Total lipids in invertebrates” and “FAs in river organic matter”. Cold topics included “Food quality for Daphnia”, “FA markers in sediments”, and “Trophic transfer in reservoirs/fish farms”. Topic modeling revealed 12 distinct research topics, indicating that the use of FAs as markers for environmental changes in freshwater ecosystems is a diverse and multifaceted field. This research spans various communities, ecosystem compartments, and types of environmental change, with most topics showing a stable publication trend over time. To enhance future research in this area, it is recommended that FA fingerprinting be further developed to target specific impacts and communities, particularly in the context of multiple stressors on freshwater ecosystems.