PURPOSE OF REVIEW: This paper reviews recent advances in a membrane bioreactor (MBR) and focuses on the features and performance of MBR configurations. Special attention is given to MBR configurations developed for improving pollutant removal and fouling control. RECENT FINDINGS: The first development discussed in this review is related to pollutant removal. Modified MBR configuration can enhance pollutant removals, such as those observed in baffled, osmotic, aerobic granular sludge, and electric field-assisted MBR. In addition, fouling is still the major problem in MBR applications. Fouling affects membrane performance stability as well as operational and capital costs. Several new MBR configurations have been developed to address fouling issues. By using dynamic membrane and free-moving particles, these new configurations make MBR operation more stable with fewer cleaning operations. In addition, lower cleaning frequency will decrease operational expenditure and capital investment. Due to their unique features, newly developed MBR configurations are proved to display high pollutant removal in wastewater treatment. Meanwhile, MBR with dynamic membranes and moving particles can decrease membrane fouling due to mechanically induced shear with lower energy consumption than shear by conventional aeration.

The structural characteristics of phytoplankton communities and their relationship with environmental factors were analysed based on survey data from the central South China Sea in summer 2020. A total of 416 separate taxa from 90 genera and 4 phyla were identified, with an average cell abundance of 572.98 cells/L. The dominant phytoplankton species were Nitzschia spp., Gyrodinium spp., Synedra spp. and Navicula spp. The Shannon-Wiener index ranged from 2.25 to 4.98, and the evenness index varied from 0.48 to 0.93. Correlation analysis showed that total cell abundance was negatively correlated with salinity, nitrate and silicate and was positively correlated with nitrite. Compared with the historical data, Thalassionema nitzschioides was cited repeatedly in previous researches as the dominant species. In addition, the Shannon–Wiener index showed an overall increasing trend over time, and the community structure is becoming more stable.

Southeast Brazilian bays have been increasingly degraded by untreated organic loads. Therefore, to assess fecal contamination status, sediment quality regarding polycyclic aromatic hydrocarbons (PAHs), and sources of organic matter (OM), we have determined fine-grained and total organic carbon (TOC) content and concentrations of PAHs and sterols in twenty-six surface sediment samples in Sepetiba Bay. The fine-grained (1–26 %), TOC (0.20–3.45 %), PAHs (<LQ – 78.27 ng g⁻¹) and sterols (0.10–21.58 μg g⁻¹) results showed a decreasing trend from the internal to the external sector of the study area. The diagnostic ratios of selected PAHs and sterols indicated a mixture with significant contribution from continental and pyrolytic OM in all stations. The fecal contamination is significant to the internal sector of Sepetiba Bay. Considering a site-specific sediment quality guidelines (SQGs) the PAHs levels with more restricted benchmark values indicate the harbor and the internal sector as contaminated.

To determine the ecological effects of atmospheric wet deposition of dissolved nutrients on the coastal waters around the Yangma Island, rain and snow samples were collected and analyzed at a shore-based site for one year. The wet deposition fluxes of dissolved inorganic nitrogen and phosphorus (DIN and DIP) and dissolved organic nitrogen and phosphorus were 69.2, 0.136, 13.3 and 0.143 mmol m⁻² a⁻¹, respectively. In summer, the new production fueled by wet deposition accounted for 19.3 % of that in seawater and 16.4 % of the amount of particulate organic carbon ingested by the scallops cultivated in the study area, indicating the potential contribution of wet deposition to fishery resources. Meanwhile, precipitation increased the seasonal average DIN/DIP ratios in surface seawater by 17.7 %, 16.3 %, 23.4 % and 6.5 % in spring, summer, autumn and winter, respectively, which could change the composition of ecological community and cause obvious negative impact on the ecosystem and mariculture.

This study aimed to assess the maternal offloading of metals in the Brazilian guitarfishPseudobatos horkelii through determining essential (Cr, Cu, Fe) and non-essential (Cd, Hg, Pb) metal concentrations along two generations of this species: pregnant females and offspring. The maximum transfer capacity (ECER) and offspring/mother ratio were calculated to estimate the extent of offloading, as well as the proportion of contaminants presented in offspring related to the maternal concentrations. Transfer efficiency was element-dependent. Chromium had the highest ECER (99.7%), followed by Hg (67.7%). Other essential metals were less transferred (9.6–35.6%) and Cd and Pb were not detected in uterine content samples. The relationships between maternal length and concentration, as well as transfer capacity were not significant, indicating that females might be continuously exposed, and that offloading might not excrete metals efficiently. On the other hand, embryos are exposed to these elements which could impair embryonic development.

To explore the influence of tidal events on protozoan periphyton fauna along tidelines, a 1-month baseline survey for bioassessment was conducted in an intertidal zone of the Yellow Sea, Northern China. A total of 27 protozoans species were identified among five sampling sites along five tidelines (sites A–E). The periphytic protozoans showed a significant variation in species distribution and community pattern along five tidelines. Species richness decreased from the high tideline (site A) and reached the minimum value at the middle tideline (site C), followed by an increase up to the low tideline (site E). Individual abundances peaked at site C and leveled off at the other four tidelines. Species richness, evenness, and diversity showed low value at site C compared with those at the other four sites. These findings suggest that periphytic protozoan fauna was shaped by tidal events along the tidelines of marine ecosystems.

Investigations of the physicochemical degradation of personal protective equipment (PPE) under controlled environmental conditions are largely lacking. Here the chemical and physical changes of face masks and gloves (recovered from the marine environment) were evaluated after exposure time up to 60 days of simulated environmental conditions. The results suggested that the polymer backbone of PPE suffers typical changes induced by sun exposure. Changes in the intensity of diffraction peaks indicated shifts in the crystallinity of PPE, possibly altering their thermal behavior. Signs of physical degradation in PPE, such as ruptures, and rough surfaces, which exacerbated over time were also detected. Additionally, signals of some elements of concern, such as Cu and Mo, and elements typically found in seawater were detected. The results of this study allowed us to better understand the degradation of typical PPE items in the marine environment, ultimately resulting in the release of microplastics and chemical contaminants.

The presence of floating marine anthropogenic litter in marine environments increase the possibility of transportation of fouling organisms using these substrates as a vector, mainly for those species with close affinities to artificial substrates. The objectives were to qualitatively and quantitatively report anthropogenic litter and its associated fouling groups arround Ilha Grande Bay (IGB). Litter was collected, classified and examined for the presence of fouling organisms on beaches located at two different levels of wave exposure during rainy and dry seasons. The types of litter do not differ among beaches, and the highest density and cover of fouling were reported on exposed beaches due the currents, winds, and storm waves. Bryozoans, barnacles, polychaetes, and mollusks were the most frequent fouling groups observed in litter and represents a potential vector for the dispersion of species in the IGB and adjacent coastal areas.

The Red Sea is exposed to metals from a large variety of natural and anthropogenic sources. In this study, we analyzed 19 common element concentrations in 14 Red Sea zooplankton samples using inductively coupled plasma-optical emission spectrometry (ICP-OES). The average metal or metalloid concentrations of the Red Sea zooplankton were: Ca > Sr > Fe > Al > Zn > As > Cu > Mn > Cr > Mo > Ni > Pb > Cd. The As, Ca, and Cu concentrations significantly increased with increasing latitude, while Cd concentrations decreased (p < 0.01). Our study indicated that anthropogenic activities (i.e., cement factories and oil refining industries) might be the predominant sources of significantly high Cr (1718 mg/kg), Fe (11,274 mg/kg), Mn (57.3 mg/kg), Mo (286 mg/kg), Ni (226 mg/kg), Pb (332 mg/kg), and Zn (17,046 mg/kg) concentrations that recorded in the Central to North Red Sea zooplankton.

In this study, the abundance, and characteristics of the microplastics on the southern coast of the Black Sea were assessed. More than 70% of the detected microplastics were smaller than 2.5 mm and mostly consisted of fibers and fragments. The average microplastic abundance in the beach sediment and seawater were 64.06 ± 8.95 particles/kg and 18.68 ± 3.01 particles/m³, respectively. The western coast of the study area (Marmara region) was the most polluted area, and a spatially significant difference was determined in terms of abundance. The composition in the beach sediment (particles/kg) was dominated by styrene acrylonitrile copolymer (SAC) (40.53%), polyethylene terephthalate (PET) (38.75%), and polyethylene (PE) (6.91%), whereas the seawater (particles/m³) was dominated by PET (57.26%), PE (13.52%), and polypropylene PP (11.24%). The results of our study can be a baseline for environmental modeling studies and experimental studies on the marine organisms inhabiting the Black Sea.