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Over the past several decades, evolution models for both the PSP and the SCS have been established reasonably. For example, the time of the NNW oriented seafloor spreading of the SCS along the South China Block was calibrated to begin at 33 Ma and cease at 15 Ma, respectively, during which the east subbasin (33-15 Ma) formed first and the southwest subbasin (23.6-16 Ma) formed later (

Directly integrating anammox into sewage treatment is attractive, but anammox bacteria (AnAOB) enrichment is complex due to vicious competition from heterotrophic bacteria (HB). A novel strategy of optimal organics management using a preanaerobic stage and subsequent limited-oxygen conditions (0.32 ± 0.15 mg-O 2 /L) is applied, and a hybrid autotrophic− heterotrophic denitrification process is developed to treat sewagelike wastewater with a COD/N ratio of 3.1 for 420 days. The stable process was achieved, and a high total nitrogen removal rate of 0.53 kg-N/(m 3 •d) was obtained compared to conventional nitrification/denitrification. The 16S rRNA high-throughput sequencing analysis suggested that the relative abundance of the nonendogenous HB (Denitratisoma and Thauera) was drastically reduced (P ≤ 0.001), whereas the endogenous denitrifying HB (Candidatus (Ca.) Competibacter) was significantly enriched in the anammox granules (9.98%, P ≤ 0.001). Moreover, Ca. Competibacter as an inner core and Nitrospira and Ca. Brocadia as an outside coating of the anammox granules indicated the cooperation of AnAOB with HB as revealed by laser-scanning confocal microscopy and qPCR. In situ tests further confirmed nitrite from two pathways (partial nitritation and endogenous partial denitritation) that favored AnAOB enrichment. Optimal organics management can mitigate the competition of HB with AnAOB by redirecting the metabolic pathways and microbial community, which is critical to directly integrating anammox into sewage treatment.

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