Ever since I heard of it the first time the black earth phenomenon in the Amazon has always fascinated me, according to the wikipedia article terra preta will give a 38-45% higher yield of rice without fertilization when compared to fertilized ferralsol and the Biochar Fund gives an even higher figure of 840% (the figure is given in an unclear manner, it’s likely it refers to total biomass of the plants, not yield). Wherever the truth may be it’s obvious that this is powerful stuff that can simultaneously increase the crop yields in tropical countries while at the same time eliminating the need for expensive artificial fertilizers.... more