OICC Press Journal of Crop Nutrition Science 2538-2470 11 1 2025 03 31 Research on the Effects of Vinasse and Humic Acid Along with Optimal Use of Chemical Fertilizers on Soil Nitrogen and Phosphorus Availability and Sugarcane Yield 10.57647/jcns.2025.1101.05 EN Seyedeh Zahra Jafari Naeini Department of Soil Science, Khuzestan Science and Research Branch, Islamic Azad University, Ahvaz, Iran.; Department of Soil Science, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran. Alireza Jafarnejadi Soil and Water Research Department, Khuzestan Agricultural and Natural Resources Research and Education Center, AREEO, Ahvaz, Iran. Kamran Mohsenifar Department of Soil Science, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran. Timoor Babaienejad Department of Soil Science, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran. Ali Gholami Water Studies Research Center, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran. Journal Article 2025 03 31 BACKGROUND: Replacing chemical fertilizers with organic fertilizers can play an important role in crop management. Also, by using organic fertilizers, in addition to reducing the consumption of Nitrogenous chemical fertilizers and triple superphosphate, it is possible to reduce costs and environmental pollution, which is a move towards achieving sustainable agricultural goals. OBJECTIVES: The aim of this study was to investigate the effect of Vinasse and Humic acid on soil Nitrogen and Phosphorus concentrations under Sugarcane cultivation conditions with chemical inputs. METHODS: Current research was done via split split plots experiment based on complete randomized block design with three replications. Vinasse at three level (0, 50, and 100 cubic meters per hectare) belonged to main plot, three levels of Humic acid (0, 2.5, and 5 kg.ha-1) belonged to sub plot, and two levels of fertilizer treatment (Recommended advised to consume N, P, K and 50% of Recommended) belonged to sub sub plot. RESULT: The result of analysis of variance revealed effect of effect of Vinasse, Humic acid, fertilizer and interaction effect of treatments on Nitrogen and Phosphorus concentration at both depth was significant. The highest increase in soil Nitrogen content compared to the control at a depth of (30-60) is 0.084 percent, and the highest average percentage increase in soil Nitrogen content compared to the control at a depth of 0-30 centimeters (0.081 percent) is with the use in treatments (100 m3. ha-1 Vinasse). The highest increase in soil Phosphorus compared to the control at a depth of (0-30 cm) and (30-60 cm) was 7.98 and 6.8 mg Phosphorus per kilogram of soil and with the in treatments (100 m3. ha-1 Vinasse). Consume 5 kg.ha-1 Humic acid achieve highest amount of Nitrogen, Phosphorus content and crop yield in both depths. So we can conclude that Vinasse, along with proper fertilizer management, can compensate for the lack and availability of some Nitrogen and Phosphorus in the soil and lead to a reduction in the consumption of chemical inputs and consequently reduce environmental pollution and by adding the highly nutritious elements Nitrogen, Phosphorus, and organic matter, it contributes significantly to soil fertility and plant growth. CONCLUSION: Finally according result of current research consume 50 m3.ha-1 Vinasse and 5 kg.ha-1 with 50% recommended amount fertilizer led to produce economic yield and decrease use of conventional fertilizer based on sustainable agriculture and input management.