Harnessing Diptera Diversity as a Bioindicator for Carbon and Nitrogen Loss During Litter Decomposition

Commodities

Practices

Biodiversity is a fundamental component of ecosystem function and soil health; however, agricultural intensification is a known driver of declining biodiversity. Efforts to mitigate the impact of agricultural intensification on biodiversity and ecosystem services (including decomposition) in the form of sustainable agricultural management are rising in adoption. Detecting the impact of sustainable agriculture on soil health is often challenging due to the extended time necessary to observe discernable changes. A bioindicator of soil health, connected to decomposition, C/N cycling, and microbial activity, would provide agricultural producers with a reliable tool capable of assessing the impact of management decisions early after adoption. Diptera (flies) are undervalued as ecosystem service providers but recognized for their role in decomposition and nutrient cycling. Quantifying the contributions of Diptera to decomposition in agriculture will establish this key insect taxon as a comprehensive bioindicator for soil health. I propose investigating the effect of sustainable agricultural management practices on cover crop decomposition, nutrient cycling, and soil insect diversity, with a particular emphasis on Diptera. Objectives of our project include quantifying the diversity and abundance of Diptera in sustainably and conventionally managed annual row crops, evaluating decomposition rates and C/N release of a cover crop, and assessing the relationship between Diptera emergence and cover crop decomposition. I will conduct my research at the W. K. Kellogg Biological Station in Michigan, where the United States Department of Agriculture (USDA) Long-Term Agroecosystem Research (LTAR) Aspirational Cropping Systems Experiment (ACSE) is established. The LTAR ACSE compares sustainable "Aspirational" systems with conventional "Business as Usual" systems, focusing on aspects including crop rotation, tillage, and cover cropping. I aim to advance the understanding of the relationship between sustainable agricultural management practices, soil biodiversity, and ecosystem function. By identifying the contributions of Diptera to decomposition processes, this project will provide valuable insights for agricultural management practices aimed at enhancing soil health and sustainability.

Learning Outcome(s): I will educate row crop growers about an underappreciated guild of beneficial insects in agriculture, the decomposers facilitating nutrient cycling. These agricultural producers will learn the efficacy of using a cover crop mixture of red clover, alfalfa, chicory, and annual ryegrass in soil nutrient cycling which will foster informed decision-making in agricultural management. Additionally, they will understand how soil biodiversity can be used as a bioindicator for assessing nutrient cycling and soil health.

Action Outcome(s): Empowered with a holistic understanding of sustainable soil management and biodiversity, row crop growers will be equipped to make informed decisions when adopting cover cropping and no-till, optimizing the efficacy of nutrient cycling. I expect my work will allow producers to integrate sustainable soil management with other management practices like insecticide applications to develop management strategies that reduce the disruption to soil biodiversity and the efficacy of adopting cover cropping and no-till. This will help agricultural producers convey how their management decisions translate into sustainable agriculture and meet industry priorities to the broader public.