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The article investigated the effect of substrate ratio and shock load resistance on the nitrogen removal efficiency of curtain packing anammox filler and bundle packing anammox filler. The results had shown that the nitrogen removal performance was recommendable when the NH4 +-N: NO2 −-N was set as 1:1.20, regardless of the curtain packing filler or the bundle packing filler. After the total nitrogen concentration was directly increased from 770 mg/L to 1320 mg/L for 12 h. From the perspective of the steady of nitrogen removal performance, the bundle packing filler was better than curtain packing filler, and the effluent TN concentration was beyond 70 mg/L. Subsequently, within 1 day when the influent TN concentration increased to 770 mg/L, both filler systems quickly recovered. The structure of the bundle packing was beneficial to the fixed, cultured, and aggregation of anammox bacteria made it a better filler type. The high-throughput results showed that the dominant bacteria in the two packing fillers was Candidatus Kuenenia, which accounted for 15.16% and 22.85% in the curtain packing filler and the bundle packing filler system respectively.

The sensitivity of female and male individuals of the same species to environmental stress is often different. The present study investigated sea urchins (Strongylocentrotus intermedius) of both sexes that were exposed to water-accommodated fractions of heavy fuel oil (HFO-WAF) for 7 d. Polycyclic aromatic hydrocarbons (PAHs) bioaccumulation in sea urchin gonad tissue was significantly increased following the exposure to HFO-WAF. However, PAHs bioaccumulation significantly differed between females and males, which may be related to the lipid content of gonad tissue. We found a significant increase in the percentage of anomalies in their larvae 24 h post fertilization. This indicates that parental exposure to HFO-WAF can have an adverse effect on the offspring, which may consequently affect population recovery and maintenance.