How does biochar impact soils and crops in a semi-arid environment?

This study investigates wood biochar’s effects on soil and crop yields over five years in semi-arid Great Plains. Findings show biochar enhances soil fertility and crop yields initially, especially above 6.25 Mg ha−1, but benefits diminish over time, highlighting its short-lived efficacy.

March 31, 2024

1–2 minutes

Blanco-Canqui, et al (2024) How does 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 impact soils and crops in a semi-arid environment? A 5-yr assessment. Field Crops Research. https://doi.org/10.1016/j.fcr.2024.109340

In recent research conducted in the semi-arid regions of the western U.S. Great Plains, the effects of wood biochar application on soil properties and crop yields were meticulously evaluated over a span of five years. This study focused on a no-till cropping system involving millet, pea, winter wheat, and sunflower rotation. Utilizing varying biochar application rates (0, 3.125, 6.25, 12.5, and 25 Mg ha−1) alongside three levels of nitrogen (N) fertilizer (0, 84, and 168 kg N ha−1), the research aimed to provide insight into the long-term benefits and limitations of biochar use in agriculture, especially in semi-arid environments where such data are scarce.The findings reveal that biochar significantly enhances soil fertility properties more than it does physical properties, with the most notable improvements observed in the first year following application. The study underscores that benefits associated with biochar, such as increased crop yield, are more pronounced with application rates exceeding 6.25 Mg ha−1 in certain years. However, combining biochar with N fertilizer did not yield additional benefits compared to using biochar alone.Interestingly, the impact of biochar on soil properties was found to diminish over time, suggesting that the positive effects of biochar on soil may be short-lived. Specifically, biochar’s influence was significantly stronger in the first year than in the third and fifth years after application. This diminishing effect raises questions about the longevity of biochar benefits in 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 and crop yield enhancement.The research contributes valuable long-term field data to the ongoing discourse on biochar’s efficacy as a soil amendment in semi-arid environments. It highlights the potential of wood biochar to improve some soil properties and crop yields, albeit with benefits that decrease over time. This study underscores the necessity for further research to determine the optimum biochar application rates and strategies for sustained soil health and productivity in semi-arid agricultural systems.