Sustainable restoration of degraded land is an important measure to meet global food demands. The use of modified biochar technology for soil improvement and environmental remediation is undoubtedly an effective  method. However, further research is needed on the impact of modified biochar on different soil phosphorus components and their biochemical properties.

In a study published in Environmental Sciences Europe, researchers from Xishuangbanna Tropical Botanical Garden (XTBG) of the Chinese Academy of Sciences and their collaborators revealed that magnesium-modified wheat straw biochar (Mg-WBC) significantly enhanced phosphorus (P) availability and improved key soil health indicators in different soil types, offering a promising strategy for sustainable agriculture and soil remediation.

The researchers measured the impact of unmodified wheat straw biochar (WBC) and Mg-WBC on phosphorus fractionation and biochemical properties under different soil conditions.

The researchers set up control and four different dose (1% and 2.5% of WBC and Mg-WBC) treatment groups applied to the Qiqihar (QY) and Harbin (HAR) soils. They evaluated the impact of biochar by determining soil chemical properties, enzyme activities, and microbial biomass.

They found that both WBC and Mg-WBC significantly improved soil characteristics. Biochar addition had a positive effect on the improvement of acidic soils. Mg-WBC significantly improved the P availability in both soils by increasing the moderately labile P content, while decreasing the non-labile P content.

The study suggested that Mg-WBC application enhanced phosphorus cycling, increased nutrient availability (especially labile P and carbon), and aided in remediating acidic soils. It promoted both agronomic productivity (higher yields) and environmental sustainability by recycling agricultural waste (wheat straw) and reducing nutrient loss.

"Magnesium-modified biochar is a powerful tool for improving soil fertility, particularly phosphorus availability in its most plant-usable forms," said Khan Muhammad Numan, a postdoctoral researcher of XTBG. "Our findings recommend that the appropriate biochar application strategy should be selected according to different soil conditions for the best soil improvement effects."

Published: 01 June 2025