Biochar, a stable form of carbon which is rich in nutrients, is considered to be an environmentally-friendly, multi-beneficial soil enhancer that is produced from the pyrolysis of biomass (Eg: plant matter, household waste or manure). This ability as a soil enhancer stems from its great potential to absorb toxic substances and restore and revive contaminated environments. The application of biochar to the soil also greatly improves soil functions. A few of these agronomic benefits include improving absorption and retention of nutrients and water in soil, decreasing the soil’s acidity and the uptake of toxins, and increasing the soil microbial diversity. In addition to these, biochar also helps reduce the emissions from biomasses that would otherwise degrade into non-CO2 greenhouse gases such as methane (CH4) and Nitrous Oxide (N2O). Studies have suggested, in theory, that 12 percent of global green-house gas emissions could be offset by producing biochar.
With tea being one of the main export oriented plantation crops in Sri Lanka, improvement of soil conditions in estates has become increasingly required with regard to many aspects. Years of neglect due to poor management practices have created unsustainable and unyielding estates. The application of chemical fertilizers have led to certain issues related to soil properties arising, for example, microbial growth issues, pH changes, water quality deterioration and so on.
In light of this, Dilmah Conservation initiated a research study to be carried out in the tea plantations to address and mitigate this present situation. Through this experiment, which was implemented in March 2016, Dilmah Conservation hopes that the deteriorating soil conditions in many Sri Lankan tea plantations may be addressed with the proposal of good agricultural practices as a sustainable solution to this.
The overall objective is to evaluate the effectiveness of biochar as a potential soil enhancer in tea cultivation and to hopefully aid in the reduction of harmful chemical fertilizer use and organically improve the quality of plants as well as surrounding ecosystems and environment both above and below ground.
Large scale applications were completed in several Dilmah plantations, which have yielded extremely positive results for productivity. The first site for the biochar application was at Rilhena Estate followed by Kahawatte Plantations, chosen for its different agronomic and climatic conditions. At present, research is being conducted at the Endana estate. More specifically, this research conducted by Dilmah Conservation expects to evaluate the potential usage of biochar as a multi-beneficial soil amendment, so as to be incorporated in tea fields to increase yield and quality of tea. Helped Dilmah Headquarters in Peliyagoda, Sri Lanka achieve carbon neutrality through carbon sequestration.