https://asi.ucdavis.edu/news/new-study-biochar-helps-yields-...
https://journals.plos.org/plosone/article?id=10.1371/journal...
Some studies even show that biochar soil amendments accelerate the breakdown of humus and release net positive CO2 to the atmosphere:
> Our results showed that biochar application increased soil CO2 fluxes by 43.33% in unfertilized soils, but decreased by 8.61% in N-fertilized soils, consistent with the meta-analysis of Liu et al. (2016).
The metastudy did go into detail about N2O and CH4 as well in both fertilized and unfertilized soil.
https://www.youtube.com/watch?v=svNg5w7WY0k&t=5s
This is on my to-do list:
http://climatechangeacademy.com/courses/carbon-removal/4
I found a lot of information from comments here:
I was introduced to it on this podcast episode: https://podcasts.apple.com/us/podcast/permaculture-for-the-f...
It lasts for at least a couple thousand years, and is considered a long-lasting soil amendment.
The presence of biochar creates habitats for those microbes and conserves nutrients, making the soil fertile, even in areas like the Amazon where rainfall normally washes away nutrient accumulations. It can be made with processes that sequesters carbon, both in the charring stage (via gassifier designs optimized towards sequestering) and during the inoculation stage where it can capture greenhouse gases emitted by a compost pile.