Biochar is fine-grained, highly porous charcoal that help soils retain nutrients and water. Specifically, the use of biochars in tropical soils has been linked to stronger root structure, higher PH, greater nutrient uptake and reduced watering requirements.
Biochar use in soils
The soil fertility benefits of biochar as soil enhancer that holds carbon and makes soils more fertile, boost food security, discourage deforestation and preserve cropland diversity.
– Reduced leaching of nitrogen into ground water
– Possible reduced emissions of nitrous oxide
– Increased cation-exchange capacity resulting in improved soil fertility
– Moderating of soil acidity similar to lime
– Increased water retention
– Increased number of beneficial soil microbes
Biochar can improve almost any soil. Areas with low rainfall, nutrient-poor soils, acid soil will most likely see the largest impact from addition of biochars.
All organic matter added to soil significantly improves various soil functions, not the least the retention of several nutrients that are essential to plant growth. What is special about biochar is that it is much more effective in retaining most nutrients and keeping them available to plants than other organic matter such as for example leaf litter, compost or manures. Interestingly, this is also true for phosphorus which is not at all retained by ‘normal’ soil organic matter.
Biochar is much more persistent in soil than any other form of organic matter. The long persistence of biochar in soil also makes it a prime candidate for the mitigation of climate change.
The extremely porous nature is found to be effective at retaining both water and water-soluble nutrients. It is extreme suitability as a habitat for many beneficial soil micro organisms. When biochar is pre-charged with these beneficial organisms, it becomes an extremely effective soil amendment promoting good soil and, in turn, plant health.