STiR coffee and tea magazine

32 STiR coffee and tea / Issue 5, 2017 (October / November) By Dan Bolton Soil samples indicate the effectiveness of bio char on crop yields Working biochar into the soil Helping Put the Earth Back in the Black TALAWAKELLE, Sri Lanka The leaves that pluckers harvest take with them tons of essential minerals and trace metals that must be replaced to sustain the health and yields of tea bushes. Constantly generating new leaves stresses tea bushes that over 150 years have con- sumed great quantities of soil nutrients. Replenishing these chemicals is expensive in countries like Sri Lanka that lack a domestic fertilizer industry. Soil inputs are expen- sive and they expend petroleum, contributing to greenhouse emissions. Island coun- tries like Sri Lanka bear the additional shipping expense of hauling millions of tons of minerals across the sea. Biochar is a promising answer. Senior soil scientist Dr. R. S. Dharmakeerthi calls Biochar "a black gold that could improve the living standards of the poor in Sri Lanka in many ways while protecting our environment." Dr. Keerthi Mohotti, deputy director of research at the Tea Research Institute of Sri Lanka, the nation's premier institution on tea research, explains that unlike other perennial plantation crops tea requires high soil fertility. "In Sri Lanka it is provided through integrated soil management strategies that are laborious and costly. Climate change has led to frequent heavy rains that speed up soil degradation. Hence, alternative and grower friendly options are a necessity to meet such challenges today," he said. What is biochar? The International Biochar Initiative (IBI) (www.biochar-international.org) describes biochar as a modern adaptation of the 2000-year-old practice of burning agricultural waste to improve soil. Biochar holds carbon, boosts food security, increases soil bio- diversity, and discourages deforestation, according to IBI. "The process creates a fine- grained, highly porous charcoal that helps soils retain nutrients and water. It acts as a charcoal filter to concentrate and prevent minerals from leaching into groundwater and causing pollution."

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