Climate change is one of this generation’s most persistent and pressing problems. It not only affects sea levels, habitats, and wildlife, but also resources vital to human survival. One of theses resources is food: as we deplete fertile land, waste fresh water, and cause severe weather changes, we increase the risk of our global food security.
The rapid growth of the human population means that food security will soon become a concern for both developing and developed countries alike. To address this issue, Dr. David J. Beerling and his colleagues from the University of Sheffield are researching agricultural practices that not only preserve the environment, but also act to undo human pollution. In a paper published by Nature on 17 January 2018, the team put forth a farming practice that uses silicate rocks to remove carbon dioxide from the atmospheres.
The process involves the regular addition of small pieces of calcium and magnesium-bearing rocks into the soil. The silicate rocks react with the carbon dioxide in the atmosphere to form stable alkaline forms of carbon dioxide (namely bicarbonate and carbonate), then carry the compounds with the rest of the soil runoff into the ocean. This process therefore assists with the reduction of carbon dioxide in the atmosphere (a major cause of Earth’s severe climate change).
Dr. Beerling’s research also indicates that his team’s process improves crop performance, and can act as a substitute for fertilizers. The silicate rocks can also increase the pest and disease protection of the crop. Dr. Beerling hopes that the benefits will create an incentive for farmers to adopt the practice.
Of course, there are financial and practicality issues preventing this novel process from being adopted. For instance, a substantial amount of silicate rocks is required to accomplish the carbon sequestration (or removal of carbon dioxide from the atmosphere). For 10 to 30 tonnes of carbon dioxide per hectare of crop per year, 9-27 pentagrams of silicate rock is needed. Moreover, a cost-effective way to obtain these rocks does not exist either. Our current rock mining, grinding, and spreading technologies would likely yield carbon emissions equivalent to 10-30% of the carbon that would be sequestered by the silicate rocks obtained. The research paper consequently emphasizes the need for innovation in the industrial sector in sustainable rock mining practices.
Finally, because this idea is so novel, further research and greater public acceptance is needed for it to become common practice. If effective, however, silicate rocks have the potential to reshape sustainable agricultural practices.