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 is gaining attention for its potential to improve soil health and agricultural productivity. In a recent study published in Scientific Reports, Rashid et al., explored the use of de-ashed biochar as a carrier for slow-release nitrogen fertilizers (SRFs) in alkaline calcareous soils. The research addresses the limitation of traditional SRFs synthesized from pristine biochar, which often underperform compared to conventional nitrogen fertilizers.  

The authors synthesized biochar-based slow-release fertilizers (BSRFs) using modified/de-ashed biochar as the nitrogen carrier. They hypothesized that BSRFs would enhance nitrogen use efficiency (NUE), particularly in alkaline calcareous soils where suitable SRFs are lacking. A two-year field experiment was conducted to compare the efficacy of BSRF (formulated with a 1:1 mass ratio of de-ashed biochar and urea) with conventional urea (CU) and commercial slow-release fertilizer (CSRF) under wheat (Triticum aestivum L.) and maize (Zea mays L.) cropping systems in two different textured soils.  

The results demonstrated that BSRF significantly increased the retention of soil mineral nitrogen (NH4+-N, NO3–N) compared to CU and CSRF. Consequently, this enhanced retention led to increased nitrogen uptake by the crops, with an improvement of up to 23.71% in wheat and 26.55% in maize. Additionally, the study observed an increase in soil organic carbon (SOC) content, with improvements of up to 50.7% and 45.6% recorded in wheat and maize crops, respectively.  

In conclusion, the findings suggest that BSRFs are a promising alternative to conventional nitrogen fertilizers, particularly for alkaline calcareous soils. By improving nitrogen retention and uptake, BSRFs can enhance crop productivity and promote soil health. The use of de-ashed biochar as a carrier for slow-release fertilizers represents a significant advancement in sustainable agricultural practices.  

Source: Rashid, M., Hussain, Q., Khan, K. S., Alvi, S., Abro, S. A., Akmal, M., … & Iqbal, R. (2025). De-ashed-biochar slow-release N fertilizer increased NUE in alkaline calcareous soils under wheat and maize crops. Scientific Reports, 15(1), 7748. https://doi.org/10.1038/s41598-025-90651-7