Enhancing Irrigation Performance in Loamy Sand Soil Using a Blood–Bran Mixture: Effects on Soil Moisture Dynamics and Crop Response

Abstract Water scarcity is a growing concern in arid and semiarid regions. The prevailing coarse-textured soils in these areas pose significant challenges for crop production. This study aimed to evaluate the effect of a blood–bran mixture as an organic soil amendment on cotton growth, yield, and water productivity under deficit irrigation conditions in loamy sand soil. Additionally, the study assessed the impact of the amendment on soil moisture distribution patterns. The amendment composed of a mixture of animal blood and wheat bran at a mixing ratio of 50 ∶ 50 w / w . Open field experiments were conducted during two consecutive seasons, 2023 and 2024. Three irrigation levels (100%, 80%, and 60% of crop water requirements) and four concentrations of the blood–bran (BB) amendment (0, 5, 10, and 15 Mg ha − 1 ) were evaluated. The results revealed that crop growth and productivity, and soil moisture distribution patterns were significantly affected by the application of BB amendment. Incorporating the BB amendment significantly enhanced plant height, chlorophyll content, number of bolls per plant, yield and water productivity ( p < 0.05 ). The results also revealed that moderate water deficit maintained cotton yield while improving water productivity compared with full irrigation. The application of BB amendment at 15 Mg ha − 1 and 80% of irrigation water requirements achieved the highest water productivity without significant yield reductions. Combining nitrogen-rich slaughterhouse blood waste with hydrophilic wheat bran offers a promising and sustainable solution for enhancing soil quality and agricultural productivity.