In Thailand, Green Carbon Inc. has partnered with the Rubber Authority of Thailand (RAOT) and Mahidol University to complete a controlled greenhouse experiment evaluating the application of rubberwood-derived 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 in the national natural rubber sector. The tri-party initiative assessed the agronomic impacts of pyrolyzed waste rubberwood across varying application rates and nutrient management regimes. By utilizing abundant domestic agricultural residues, the collaboration aims to establish a sustainable management framework that improves agricultural efficiency while creating high-integrity nature-based carbon removal pathways.

The primary challenge driving this research is the combination of soil degradation, escalating synthetic fertilizer expenses, and climate vulnerabilities affecting Thailand’s rubber plantations. Natural rubber cultivation faces declining soil quality and nutrient retention capacities, which limits plant development and reduces operational profitability for local farmers. Additionally, the industry generates over 1.5 million tons of waste rubberwood annually, presenting an underutilized biomassBiomass is a complex biological organic or non-organic solid product derived from living or recently living organism and available naturally. Various types of wastes such as animal manure, waste paper, sludge and many industrial wastes are also treated as biomass because like natural biomass these More stream that requires sustainable valorization strategies to mitigate agricultural waste and support national decarbonization targets.

To address these soil quality and waste management issues, Mahidol University conducted a controlled study evaluating biochar application rates of 0%, 1%, 3%, and 5% combined with chemical fertilizers, cow manure compost, and fish-derived bio-extracts. Green Carbon provided technical design and biomass processing expertise, while RAOT supervised sampling and analytical procedures on rubber tree seedlings. The researchers evaluated key performance metrics, including seedling height, root biomass development, soil nutrient retention, microbial community activity, and overall fertilizer use efficiency under controlled environmental conditions.

The outcome of the experiment confirmed that combining rubberwood biochar with appropriate nutrient sources enhances seedling growth, improves soil physical properties, and increases beneficial soil microbial activity. Although biochar was determined to function 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 rather than a full replacement for fertilizer, the trial demonstrated improved nutrient retention and fertilizer efficiency. Moving forward, Green Carbon and RAOT plan to expand into commercial-scale field trials across mature plantations, supporting RAOT’s seedling distribution program and advancing carbon credit generation through international registries such as Puro.earth and Isometric.