hii Link haipo kwenye lugha yako, kuangalia kwa: English (en),
au tumia ufasiri wa google:  

www.sciencedirect.com/topics/agric...s/terra-preta

For instance, Terra Preta soils and other anthropogenic soils amended with PyC as char that has aged with time have shown a high capacity of nutrient retention and crop productivity (Cheng et al., 2008;

From: Advances in Agronomy, 2017