The benefits or otherwise of biochar

There are some very interesting ideas around 'biochar':
AgriChar: towards a carbon-negative agriculture
The Biochar Economy
The Biochar Blog • Buy Biochar From Wakefield

And this blog has looked at some of them:
Futures Forum: Sidmouth Climate Week >>> soil carbon sequestration >>> or: We've been treating our soil like dirt

However, a recent study questions the use of biochar in this part of the world:


No biochar benefit for temperate zone crops, says new report

Date:April 25, 2017

Scientists believe that biochar, the partially burned remains of plants, has been used as fertilizer for at least 2,000 years in the Amazon Basin. 

Since initial studies published several years ago promoted biochar, farmers around the world have been using it as a soil additive to increase fertility and crop yields. 

But a new study casts doubt on biochar's efficacy, finding that using it only improves crop growth in the tropics, with no yield benefit at all in the temperate zone.


No biochar benefit for temperate zone crops, says new report -- ScienceDaily
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