Umoren, et al (2024) The effectiveness of various 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 types in enhancing the phytoremediationThis is a technique that uses plants to clean up contaminated soil or water. Biochar can enhance phytoremediation by improving soil conditions and promoting plant growth, allowing plants to absorb and break down pollutants more effectively.   More of soils polluted with petroleum hydrocarbon. Journal of Plant Nutrition and Soil Science. https://doi.org/10.1002/jpln.202300285

Biochar, a form of charcoalCharcoal is a black, brittle, and porous material produced by heating wood or other organic substances in a low-oxygen environment. It is primarily used as a fuel source for cooking and heating.   More used as a 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, has shown promise in enhancing the cleanup of petroleum hydrocarbon-contaminated soils. This recent study aimed to assess the effectiveness of different biochar types, specifically maize stalk biochar (MSB) and nipa palm biochar (NPB), in improving soil quality and promoting plant growth in polluted environments.

Conducted from July to October 2021 at an automobile workshop site, the experiment utilized a randomized complete block design with various plots treated with biochar at 20 tons per hectare, while control plots received no biochar. Soil samples were analyzed both before and after treatment.

Initial soil analysis of the polluted site revealed high levels of bulk density, moisture, organic carbon, and heavy metals like cadmium, chromium, lead, and zinc compared to unpolluted soil. These conditions were coupled with lower hydraulic conductivity (the soil’s ability to transmit water) and available nutrients like phosphorus, manganese, and iron.

Post-treatment results were promising. The application of both MSB and NPB significantly reduced total petroleum hydrocarbons, cadmium, and chromium levels in the soil. NPB was particularly effective, achieving the lowest concentrations of petroleum hydrocarbons, lead, manganese, and zinc, while MSB excelled in reducing cadmium and chromium.

Interestingly, heavy metal accumulation was greater in the leaves than in the fruits of the plants grown in treated plots, with NPB plots showing the highest concentrations. NPB-treated plants also demonstrated superior growth, with taller plants and wider leaf areas.

These findings suggest that nipa palm biochar (NPB) is particularly effective for phytoremediation, the process of using plants to remove contaminants from soil, making it a valuable tool for managing petroleum hydrocarbon-polluted soils.