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Abstract
Degraded soil health conditions are major constraints to the sustainable production of row crops in the state of Georgia and most states in the Southeastern United States. The warm temperatures, as well as intensive rainfall, rapid mineralization of organic matter, and depletion of mineral-derived plant nutrients. Moreover, reliance on conventional tillage (CT) for seedbed preparation further degrades soil health. Management practices such as conservation tillage, cover crops (CCs), and organic amendments (OAs) are employed to improve soil health and row crop productivity. However, there are shortcomings associated with individual management practice. Integrating these practices could mitigate the limitations and augment the benefits of each management practice. Field studies were established to evaluate the individual and integrated impacts of tillage, CCs, and OAs on soil health and row crop productivity. The row crops evaluated were corn (Zea mays L.), cotton (Gossypium hirsutum L.), and peanut (Arachis hypogaea L.). Cereal rye (Secale cereale; CR) was used as the cover crop, and the OAs was a combination of animal manure and biochar (BC). The studies were established at two locations: (1) the USDA-ARS Bellflower Farm in Tifton and (2) the Southeast Georgia Research and Education Center in Midville, GA. In the first study, the integration of CCs and OAs into strip tillage (ST+Int) minimized soil compaction compared to strip tillage (ST) after tillage operations in the third year. Overall, integrating CCs and OAs into CT (CT+Int) and the ST+Int increased soil respiration and organic matter within the 0-15 cm depth, but the effects were not consistent across years. The various management systems had a minimal impact on cotton productivity and fiber quality. Moreover, the integrated sustainable management systems did not consistently improve soil biochemical properties. The findings of the second study showed that reduced tillage (RT) produced similar cotton, peanut, and corn yields as the CT, indicating the ST was effective in seedbed preparation. Cotton responded favorably to poultry litter (PL) application in RT and CR (RT+CR+PL), especially when compared to only RT+CR. Also, integrating RT, CR, PL, and BC did not substantially improve soil health.