Masters Theses
Date of Award
5-2025
Degree Type
Thesis
Degree Name
Master of Science
Major
Environmental and Soil Sciences
Major Professor
Sindhu Jagadamma
Committee Members
Debasish Saha, Jennifer Franklin
Abstract
While organic farming is growing in the U.S., its climate change mitigation potential is often questioned due to the heavy dependence on tillage for successful crop production at the expense of soil organic carbon (SOC). Therefore, it is critical for organic systems to transition to or implement management practices to balance productivity with environmental stewardship. This thesis tested the effectiveness of two management strategies to improve climate change mitigation and adaptation potential of organic systems. Our objectives were to quantify the SOC accumulation potential of implementing a perennial agroforestry system (AFS) which minimizes soil tillage and maximizes C inputs (study 1). However, when perennial systems cannot be implemented, we also evaluated whether high-quality compost amendments can offset tillage-related soil degradation by adding a source of C (study 2). Both studies were conducted at Caney Fork Farms, a certified organic farm in middle Tennessee. To meet the objectives, the first study quantified SOC stock and fractions near trees of two ages (4- and 7-years-old) and three distances from trees (0.5, 2, and 15 m) on SOC in a silvopasture AFS. The second study involved a field experiment to test 3 rates of compost made using the Biologically Enhanced Agricultural Management (BEAM) principle (0.56, 1.12, 2.24 Mg ha-1) compared to windrow compost (22.4 Mg ha-1), the co-application of BEAM with half the rate of windrow compost, and a control on soil health metrics and crop performance for one year. Study 1 revealed that SOC storage and stabilization were increased at 0.5 m from 7-year-old trees, likely from enhanced tree C inputs from older trees; implying that growing trees in a pasture is an effective climate change mitigation strategy that may increase over time. Study 2 did not reveal any improvement in soil health or crop performance of applying compost to an organic reduced tillage system after one year. This thesis highlights how improving the climate change mitigation potential of organic systems by increasing C inputs is feasible in perennial systems but more challenging for tilled systems and likely takes several years after strategies have been implemented to be effective.
Recommended Citation
Albert-Black, Cecilia, "Integration of Trees and Compost Amendments on an Organic Farm for Soil Carbon and Soil Health Benefits. " Master's Thesis, University of Tennessee, 2025.
https://trace.tennessee.edu/utk_gradthes/13867
Comments
I made sure all tables and figures were listed after they were mentioned in the text, I fixed the headers, formatting, and table of contents.