Other scientists have looked at materials like leaf compost or manure, while Professor Brown favors composts high in iron content, like the sludge from wastewater treatment.
The soil contains such components as oxidized iron, after a long period of oxidation, gradually added and mixed in the soil that produced this extraordinary reddish brown soil.
这里的土地里富含氧化铁，土壤里的铁质经过氧化慢慢沉积下来，逐渐形成了炫目的红棕色。
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The hepatocytes and Kupffer cells here are full of granular brown deposits of hemosiderin from accumulation of excess iron in the liver.