Weed Management Influences the Accumulation of Organic Matter in the Soil and Productivity in Coffee Farming

The management of weeds can influence organic matter (OM) and organic carbon (OC) levels, impacting the productivity and sustainability of coffee plantations. This study aimed to evaluate OM and OC levels in coffee soils under different weed management practices and their influence on coffee tree physiology and productivity. The experiment featured six treatments (without weeding, manual weeding [MW], brushcutter, trenching, contact herbicide [CH], and pre‐emergent herbicide [PEH]) and a control. Soil samples were collected at three depths (0–10, 10−30, and 30–60 cm) for OM, OC, and density analysis. Additionally, coffee productivity was measured over four harvests (2020–2023), while gas exchange parameters were evaluated during the final year of the study. Weed management using PEH initially resulted in higher productivity in the 2020 harvest; however, no significant differences in yield were observed among treatments in the following 3 years. Data showed that the continuous use of PEH, followed by CH and MW, most negatively impacted soil properties, as these methods eliminate the vegetation cover that protects OM and soil structure. This led to lower soil quality over the 4‐year study, evidenced by significant reductions in OM and OC and increased soil bulk density. The principal component analysis highlighted the strong correlation between water‐use efficiency and soil OM and OC levels. Therefore, management practices that preserve vegetation cover are essential to promote environmental conservation and sustainability of the production system.