Microbial community changes and metabolic pathways analysis during waste activated sludge and meat processing waste anaerobic co-digestion.

Waste activated sludge (WAS) and meat processing waste (MPW) were acted as co-substrates in anaerobic co-digestion (AcD), and biochemical methane potential (BMP) test was carried out to investigate the methane production performances. Microbial community structure and metabolic pathways analyses were conducted by 16S rRNA high-throughput sequencing and functional prediction analysis. BMP test results indicated that AcD of 70% WAS+30% MPW and 50% WAS+50% MPW (VS/VS) could significantly improve methane yield to 371.

Simultaneous recovery of short-chain fatty acids and phosphorus during lipid-rich anaerobic fermentation with sodium hydroxide conditioning.

Anaerobic fermentation (AF) could achieve simultaneous recovery of short-chain fatty acids (SCFAs) and phosphorus (P) when waste activated sludge (WAS) and meat processing waste (MPW) act as co-substrate. However, long-chain fatty acids, the degradation intermediates of lipids, always inhibit anaerobic microbial activity. Therefore, sodium hydroxide (NaOH) conditioning was applied to improve the lipid-rich AF performance in this study.

Spatiotemporal changes in net primary productivity before and after the development of unused land in the hilly areas of Hebei, China.

Net primary productivity (NPP) plays an important role in the carbon cycle of an ecosystem. To explore the impact of unused land development on NPP, this study adopted an improved Carnegie Ames Stanford Approach (CASA) model to analyze the changes in NPP before and after the development of unused land in Tang County, Hebei Province, in 2000, 2007, and 2018. The results showed that, due to the changes in land use types from unused land, forestland, arable land with high NPP values to urban and rural residential land, traffic land with low NPP values, and the changes in precipitation and temperature, the NPP in the study area showed an overall trend of decreasing first and then rising from 2000 to 2018.