Biochar- Black Earth Biotechnology

It can be described as a handful of charcoal, but Terra Preta (black earth), an ancient Amazonian agricultural practice, is gaining widespread attention. It is called “Biochar” or “Agrichar” these days, and it offers great potential for our planet. It may play a significant role in addressing issues of climate change, lessening erosion, improving crop yields and other environmental benefits.

Biochar is a process where carbon is drawn from the atmosphere. Biochar stores carbon in the ground for hundreds of years and its potential in reducing greenhouse gases (GHGs) is impressive. Biochar diminishes carbon release and reduces the impact from all farming and agricultural waste. Both the burning and natural decomposition of agricultural matter contributes to a vast amount of carbon released into our air. Biochar uses waste as feedstock—products typically mulched, composted or left to rot. Biochar stores carbon in the ground for long periods of time (estimates range from hundreds to thousands of years) and reduces atmospheric GHG levels, including nitrous oxide and methane in addition to CO2. Also there are research that Biochar it increases soil fertility, lessens erosion, increases agricultural productivity and improves water quality.

The third largest carbon pool on the Earth’s surface is the soil. There are various ways we can reduce greenhouse gas emissions such as minimizing tillage, diminishing or eliminating the use of nitrogen fertilizers, and preventing erosion. By enriching our soil with carbon we can store vast amounts of extra carbon when we bury it in the form of Biochar (biomass heated in a low-oxygen environment).

Roughly 30% of greenhouse gases result from land use practices and exceed the combined emissions of the industry and transportation sectors. Advancing agricultural carbon sequestration is critical to offset global fossil fuel used in food production. When natural ecosystems are converted to agricultural land use, most carbon in the soil is simply lost as greenhouse gas. So exploring how we can capture or sequester carbon due to farming, forestry and other land use practices is a pressing necessity. Sequestration of greenhouse gases so that they are not released into the atmosphere already happens naturally through photosynthesis—it is required to grow and sustain all plant life. Exploring how we can best sequester greenhouse gases in other ways so that they are not released into the atmosphere is critical in the reduction of our carbon footprint.

In addition to reducing CO2 released into the atmosphere, Biochar has been found to decrease methane and nitrous oxide emissions from soil, thus further reducing GHG emissions. Nitrous oxide is approximately 300 times stronger than CO2 in terms of global warming potential, and laboratory studies to date show that nitrous oxide emissions were reduced by 80-90% by land application of Biochar.

Biochar provides significant benefits in addition to carbon sequestration. Studies suggest that Biochar sequesters around 30-50% of the carbon available in the feedstock being used. It allows us to manage waste—agricultural, forest, municipal, wastewater, etc.—in a more sustainable manner. It assists the soil food web to build much more recalcitrant organic carbon (living biomass microbes & fungus) in addition to the carbon in the Biochar. It reduces nitrogen leaching and nitrous oxide emissions; it augments nutrient retention and moderates soil acidity; it increases water retention and productivity.

Biochar can retain up to 50% of the feedstock carbon in charcoal under best conditions. A fine-grained, porous charcoal substance is made when Biochar is produced. When this product is used as a soil amendment, it effectively removes carbon dioxide from the air. Biochar provides a habitat for soil organisms, yet is not itself consumed by them. Biochar holds and slowly releases water, minerals and nitrogen to plants. When Biochar is used as a soil amendment along with manure or fertilizer it greatly improves the soil, its productivity, nutrient retention and availability according to several studies.

It has been concluded by some soil experts that biochar keeps nutrients from running off or leaching out of soils allowing for increased plant growth. Since adding charcoal to soils appears to increase crop production. What’s more is reduces acidity and lessens nitrogen leaching while adding potassium. This reduces the amount of fertilizer required and increases water retention.

Innovations in agriculture provide the best opportunity to remove carbon from the atmosphere by changing the way we grow our food and use our land. Unfortunately, farming over the last 10,000 years has released roughly two-thirds of our excess greenhouse gases. Various agricultural practices have mined out soil carbon, converting it to carbon dioxide.

However, there are a few environmental groups who question the benefits of this biotechnology. They feel it is “dangerously premature”, that most of the claims made by Biochar advocates are unproven, and these critics argue that it has a high potential for causing harm.

Advancing Biochar technologies have significant implications. As this technology evolves so will Biochar best management practices. Apart of this process we will find how Biochar affects and effects our soil, water, air and climate. Researching and developing biochar offers numerous opportunities and challenges. More trials and tribulation will determine whether this black earth will result in greener rewards.