Date of Defense
4-16-2025
Date of Graduation
4-2025
Department
Biological Sciences
First Advisor
Steven Bertman
Second Advisor
Kathryn Docherty
Abstract
Regenerative agriculture (RA) is a modern approach to farming that aims to restore soil health, biodiversity, and ecosystem function. Basic principles that describe RA include ‘minimizing soil disturbance, ‘keeping the soil covered’, ‘maximizing crop diversity’, and ‘keeping living roots in the soil year-round’. The practices associated with these regenerative principles, such as no-till, cover-cropping, and composting, have been shown to increase soil health and mitigate climate change. In this study, the link between RA, soil health, and crop nutrition was investigated. An agricultural field was established at Kalamazoo Nature Center’s DeLano Farms and split into 48 plots. These plots were treated with different agricultural combinations in a fully crossed experimental design. Regenerative treatments applied included compost and cover crops. Fertilizer addition, which is not a regenerative treatment, is also included as a treatment. Combinations of these treatments were tested to investigate the effect regenerative and non-regenerative treatments have on different parameters. We hypothesized that regeneratively treated plots would experience increases in soil organic matter % and extracellular enzyme activities due to regenerative agriculture’s positive effect on soil health. We also hypothesized that regeneratively treated plots would experience increases in crop yield and total phenolic content. Three crops - lettuce, spinach, and collards - were planted in the Summer 2024 growing season. Various plant health metrics were measured including chlorophyll concentration, sap brix, sap pH, shoot biomass, and total phenolic content. Soil was also sampled from all plots prior to the growing season. Various soil assays were conducted including soil organic matter, soil moisture %, water infiltration rate, aggregate stability, extracellular enzyme activities, soil pH, PLFA, and carbon and nitrogen content. Our results found that soil organic matter % and crop yield were significantly increased by regenerative compost treatments. Total phenolic content of lettuce crops was significantly increased in combined fertilizer-cover crop treatments. Extracellular enzyme activities and the total phenolic content of collards were not significantly impacted by the different treatments. Further research must be done to investigate how regenerative agricultural practices effect crop nutrition.
Recommended Citation
McKinney, Marie, "The effects of regenerative agriculture on soil and crop health on a small-scale vegetable farm in Kalamazoo, MI" (2025). Honors Theses. 3909.
https://scholarworks.wmich.edu/honors_theses/3909
Access Setting
Honors Thesis-Restricted
Restricted to Campus until
6-3-2027