In a two-year field experiment published in the Alexandria Science Exchange Journal, Laila R. Salem and her fellow researchers investigated the long-term effects of using wheat straw biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More (WSB) and sugarcane bagasse biochar (SCBB) as soil amendments on sandy soil properties and the growth of Moringa oleifera. The study used biochar doses of 0.25% and 0.50% (w/w), along with a control group, and collected soil and plant samples at the end of each year. Their primary objective was to see how these biochar types influenced the soil’s chemical properties and the plant’s growth and biochemical composition.

The study found that adding biochar generally had a positive effect on the sandy soil’s properties, although the degree of improvement varied between the types of biochar and the doses used. For instance, biochar addition caused a slight increase in soil pHpH is a measure of how acidic or alkaline a substance is. A pH of 7 is neutral, while lower pH values indicate acidity and higher values indicate alkalinity. Biochars are normally alkaline and can influence soil pH, often increasing it, which can be beneficial More, but this increase was not statistically significant over the two-season period. However, electrical conductivity (EC) showed a slight but significant increase, remaining within safe limits for plant growth. The most significant improvements were seen in the availability of macronutrients and soil organic matter (SOM). The 0.50% dose of SCBB significantly increased available nitrogen (N) by 42.86%, phosphorus (P) by 43.54%, and potassium (K) by an impressive 133.70%.

SCBB proved to be more effective than WSB in enhancing soil characteristics, particularly in increasing exchangeable cations and cation exchange capacity (CEC). The superior performance of SCBB was attributed to its higher CEC value and specific surface area (SSA) compared to WSB. Additionally, the higher organic carbon content in SCBB contributed to a greater increase in soil organic matter than with WSB. The study noted that the positive effects on soil properties were more pronounced in the first year of the experiment, while the benefits to the plant’s vegetative growth became more significant in the second year. This decline in soil benefits over time may be due to the biodegradation of biochar and organic matter in the warm climate of the study area, which can reduce its long-term effectiveness if not reapplied.

The influence of biochar extended beyond the soil, significantly affecting the growth and biochemical composition of the Moringa oleifera plants. Vegetative growth parameters like leaves dry weight, plant height, trunk diameter, and seed weight were all positively influenced by the biochar treatments. The most substantial improvements were consistently observed with the 0.50% SCBB treatment. For example, in the second season, the leaves’ dry weight increased by 22.51-fold in the 0.50% SCBB treatment compared to the control. The study also found a favorable correlation between the plant’s biochemical compositions and the 0.50% SCBB treatment in both seasons. These findings suggest that the enhancements in soil parameters, such as increased nutrient and water retention, were directly responsible for the improved plant growth and health.

The researchers concluded that the 0.50% SCBB treatment was the most effective overall, demonstrating a clear benefit to both sandy soil properties and Moringa oleifera growth. To maintain these positive effects, the study recommended that biochar should be added annually to sustain improvements in key sandy soil properties and continue to enhance plant growth parameters. This highlights the potential of using agricultural waste like sugarcane bagasse to create a sustainable and effective soil amendmentA soil amendment is any material added to the soil to enhance its physical or chemical properties, improving its suitability for plant growth. Biochar is considered a soil amendment as it can improve soil structure, water retention, nutrient availability, and microbial activity.   More for arid and tropical regions.

Source: Salem, L. R., Saleh, M. E., El-Henawy, A. E. M. A., El-Absy, K. M., & El Gamal, E. H. (2025). Biochar as an Amendment to Sandy Soil Properties and Its Effect on Biochemical Composition and Growth of Moringa oleifera. Alexandria Science Exchange Journal, 46(3), 613–635.