Do conservation practices bring quick changes to key soil properties for resource-limited farmers

Authors: SARR, SAIT - University Of Louisville; GEBREMEDHIN, MAHETEME - Kentucky State University; COYNE, MARK - University Of Kentucky; TOPE, AVINASH - Kentucky State University; Sistani, Karamat; LUCAS, SHAWN - Kentucky State University

Submitted to: Journal of the Kentucky Academy of Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/19/2019
Publication Date: 10/17/2019
Publication URL: https://handle.nal.usda.gov/10113/6811094
Citation: Sarr, S., Gebremedhin, M., Coyne, M., Tope, A., Sistani, K., Lucas, S. 2019. Do conservation practices bring quick changes to key soil properties for resource-limited farmers. Journal of the Kentucky Academy of Science. 80(1):6-16. https://doi.org/10.3101/1098-7096-80.1.6.
DOI: https://doi.org/10.3101/1098-7096-80.1.6

Interpretive Summary: Soil conservation practices such as cover cropping, animal manure use, no-tillage, and crop rotation can improve soil quality by enhancing soil physical, chemical, and biological properties. Cover crops and animal manure combination can be a viable alternative management practice and source of nutrients for intensive farming and improving soil health/quality. cover crops and manure applications as soil quality building practices by farmers is still relatively small. This research evaluated whether manure and cover crops in combination influenced the physical, chemical, and biological properties of agricultural soils. Three fertilization treatments were employed: 1) poultry manure, 2) chemical fertilizers (urea, diammonium phosphate, and potash), and 3) a non-fertilized control. A second set of treatments consisting of winter cover crops or no cover crops was used within each fertilizer treatment. Considering the site-specific soil conditions, cover crop and manure use may need longer-term assessment to reveal their impact on the yield and soil quality benefits, especially to resource-limited producers adopting these conservation practices.

Technical Abstract: Soil conservation practices such as minimum tillage, crop rotation, cover crops, and manure application have strong advocacy. Short-term proof that these practices are beneficial might improve their adoption among resource-limited producers. A two-year study (2015-2017) was conducted on a privately-owned small, limited resource farm in southwestern Kentucky to evaluate how cover crops and manuring, alone or in combination, influenced soil nutrient availability, nitrogen mineralization and crop yield. Three fertilization treatments were employed: 1) poultry manure, 2) chemical fertilizers (urea, diammonium phosphate, and potash), and 3) a non-fertilized control. A second set of treatments consisting of winter cover crops or no cover crops was used within each fertilizer treatment. The cover crop consisted of a mix of cereal rye (Secale cereale L.), Austrian winter pea (Pisum sativum L.), and crimson clover (Trifolium incarnatum L.). Summer crops consisted of a no-till maize (Zea mays L.) - soybean (Glycine max L.) rotation. Soil samples were taken before and after each cropping season and analyzed for bulk density, organic carbon content, pH, cation exchange capacity, total phosphorus (P), potassium (K), trace elements, and soil nitrogen (N) mineralization. Cover crops with or without manure enhanced soil N mineralization rates and increased soil extractable P and K but did not significantly improve yield. Considering the site-specific soil conditions, cover crop and manure use may need longer-term assessment to reveal their impact on the yield and soil quality benefits, especially to resource-limited producers adopting these conservation practices.