Thematic Discussion: Soil Quality / Carbon Sequestrations

The two major topics discussed showed considerable overlap, and related mainly to the following questions:

  • How do you show show results for carbon (C) sequestration within the project time frame?
  • What are the most important indicators of soil quality?

Suggestions regarding these issues were discussed in detail; however, the conversation eventually turned to the importance establishing the efficacy of CAPS through scientific studies. The merits of high-tech versus low-tech methods for analyzing soils and biophysical parameters were also discussed.

Major, recurring topics

  • Total organic carbon (TOC) and soil organic matter (OM)
  • Methods and issues related to measuring C changes

Disagreement

  • Importance of TOC measurements (too small to detect for C sequestration within the project timeframe, but important for evaluating soil quality)
  • Reasons for scientific documentation of CAPS impacts (as opposed to farmer perception)

Processes and products

  • Labile and stable SOC fractions
  • SOC light fraction
  • Particulate organic matter (POM)
  • Greenhouse gasses (GHGs)
  • The scientific foundation of CA in order to establish credibility among policymakers and decision makers

Conclusions

  • Soil C sequestration analyses should focus on parameters most likely to demonstrate effects within the project time frame (i.e. light fraction, POM, labile SOM)
  • Scientific documentation of the positive impacts of CAPS is necessary to establish credibility among and inform policy makers
  • Level of technological sophistication should be based on the needs of a particular project, rather than some external criterion