High versus low organic loading impact on gypsum converting communities grown on sewage

By comparing this enrichment to sewage sludge across a gradient of organic loading, we show that microbial origin, syntrophic structure, and organic availability collectively determine methane suppression and sulfate reduction efficiency. We further examined whether the balance between methanogenesis and sulfate reduction is governed by community composition, syntrophic structure, or initial inoculum biomass selected during enrichment. These results show that enrichment history, community structure, and organic availability together determine the balance of sulfate reduction and methane production during phosphogypsum treatment.