Shifting sands: putting carbon back into soils

 

Photo credit: CGIAR

A scientist conducts soil testing at the Selian Agricultural Research Institute, Arusha, Tanzania.Photo Credit: Georgina Smith/CIAT

Evaluating the effectiveness of soil carbon sequestration

The world has a carbon problem, and we all know it. Tons of carbon dioxide are emitted into the atmosphere every day, contributing significantly to climate change. But slowing the rate of emissions will be no easy feat. In order to mitigate its effects, scientists are looking at alternative ways of dealing with the issue, such as carbon sequestration.

A moving target

In recent years, carbon sequestration has gained tremendous momentum and national andinternational initiatives have been taken up. But as to exactly how much of this carbon can be mopped up through sequestration is up to debate. Some scientists believe that indeed all anthropogenic emissions could be offset in such a way, while others believe only a few percent can be.

Certain key factors contribute to this uncertainty amongst the scientists. In soil carbon sequestration specifically, where organic matter such as manure, and compost are added to the soil, there are three major factors that influence its potential:

  • The dynamic nature of soil from place to place and over time
  • Variances between agricultural practices that influence the soil’s ability to act as a carbon sink
  • The significant changes to agricultural management practices that would need to be undertaken such as no-till agriculture. Globally, the adoption of such practices by farmers will take time.

Soil carbon? There’s an app for that!

To address these issues, the International Center for Tropical Agriculture (CIAT) created an app to help farmers and scientists calculate a soil’s current amount of sequestered organic carbon, as well as the quantitative impact of soil conservation practices on sequestration over time and at different scales.

Read the full article: CGIAR-THRIVE

Published by

Willem Van Cotthem

Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.