Human-induced eutrophication of coastal water may be a major threat to aquatic life. Here, we investigated the effects of N-rich well amelioration brines (WAB) on coastal phytoplankton population's habitat in the surface oligotrophic waters of the southeastern Mediterranean Sea (SEM). To this end, we added WAB (2 concentrations) to mesocosms (1-m³ bags) to surface SEM water during summer and winter, where changes in phytoplankton biomass, activity and diversity was monitored daily for 8 days. Our results demonstrate that WAB addition triggered a phytoplankton bloom, resulting in elevated algal biomass (maximal +780%), increased primary production rates (maximal +675%) and a decrease in eukaryotic algal α-diversity (ca. −20%). Among the species that bloomed following WAB amendments, we found the potentially toxic dinoflagellate Karlodinium venificum. This study adds valuable perspective to the effect of nutrients discharged into nutrient limited SEM coastal waters, and in particular of N-derived WAB.

The heavy metals (Cu, Cr, Zn, Cd, Pb) were analysed for 217 surface sediment samples collected across 14 typical intertidal zone areas in China. The data reveals the heavy metals spatial distribution patterns and correlations among their concentrations. Cu, Zn, Cd and Cr showed similar trends of spatial variation and the correlations between the concentrations of every two heavy metals were significantly positive except for the correlation between Pb and Cr concentrations. By using Nemerow index method, Enrichment factor and Sediment Quality Guidelines, it is found that Hangzhou Bay and Jiulong River Estuary were polluted, Yingluo Bay and Dongzhaigang Bay were Cd-rich areas. Except Beidaihe shoal, Sishili Bay and Yingluo Bay that were not exposed to any ecological risk of heavy metals and had no adverse biotoxic effects, the other 11 typical intertidal zone areas were exposed to moderate ecological risk of heavy metals in the sediment with potential adverse biotoxic effects.

Sediment samples were collected from Caofeidian Long Island, China to investigate the contamination level and distribution pattern of 16 polycyclic aromatic hydrocarbons (PAHs). Source identification and risk assessment were also performed on these PAHs. The distribution patterns and source identification results indicated that the PAHs in the survey area originated from coal, biomass, and petroleum combustion as well as the combination of these three processes. Although the concentration of fluorene in the sediment exceeded the ERL level in some sampling sites, the effect range low–effect range median ratio implied a relatively low level of toxicity in these sediments. Meanwhile, the mean effects range–median quotient indicated that the 16 PAHs in sediments from Caofeidian Long Island pose a low ecological risk.

The strandline is one of the first deposition habitats of microplastics before they are integrated to the beach as a standing stock or finally removed. Beaches, entirely or partially protected by beachrocks, have different sediment dynamics and therefore may present variation in microplastic deposition. The aim of this work was to test if protected and unprotected (i.e., exposed to waves) areas of a sandy beach present different microplastic accumulation on the strandline – a habitat greatly influenced by both water and sediment dynamics. Microplastic (MP) amounts were significantly higher at the protected area (Mprotected = 642.6 ± 514.8 MP m−2, Mexposed = 130.6 ± 126.8 MP m−2, Mann-Whitney U test, U = 14.5, p = 0.0009), showing that beachrocks influence microplastic accumulation on the beach face. Therefore, hard structures parallel to the beach may also affect microplastics deposition on beach sediments, being important to consider these structures on microplastic surveys.

A cocktail of land-based sources of pollution threatens coral reef ecosystems, and addressing these has become a key management and policy challenge in the State of Hawaiʻi, other US territories, and globally. In West Maui, Hawaiʻi, nearly one quarter of all living corals were lost between 1995 and 2008. Onsite disposal systems (OSDS) for sewage leak contaminants into drinking water sources and nearshore waters. In recognition of this risk, the Hawaiʻi State Department of Health (DOH) is prioritizing areas for cesspool upgrades. Independently, we applied a decision analysis process to identify priority areas to address sewage pollution from OSDS in West Maui, with the objective of reducing nearshore coral reef exposure to pollution. The decision science approach is relevant to a broader context of coastal areas both statewide and worldwide which are struggling with identifying pollution mitigation actions on limited budgets.

Along the Upper Gulf of Thailand, coastal fences and breakwaters have been constructed using bamboo since 2005. Despite their potential benefits, bamboo structures disintegrate within seven years releasing floating debris which severely damages mangrove tree stems. The aim of the study was to investigate whether such stem damage resulted in the decline of Avicennia spp. stands along the Upper Gulf of Thailand. Tree health assessments were conducted to assess the probability of crown dieback in damaged and undamaged trees. Satellite-derived time-series of vegetation indices were used to detect long-term forest decline. In contrast to the unaffected landward mangroves, seaward mangroves were unable to recover from insect-induced defoliation events after the collapse of a nearby fence. Furthermore, there was a significantly higher probability that damaged trees showed signs of moderate-to-severe crown dieback. It is recommended that bamboo fences be secured by replacing individual stems before they become detached.

PURPOSE OF REVIEW: Phenolic wastewaters represent a serious health and environmental problem. The remediation of phenolic wastewaters using oxidoreductase enzymes has emerged as an attractive environmentally friendly treatment method. However, the loss of enzyme activity during the treatment remains a key limitation. Thus, the aim of this article is to review and assess the recent progress in utilizing surface active additives (i.e., polymers, biopolymers, surfactants, and biosurfactants) for the reduction of enzyme inhibition and, thus, the enhancement of enzymatic remediation of phenolic wastewaters. RECENT FINDINGS: The reported effect of polymeric and surfactant additives on the enzymatic remediation of phenolic pollutants is mixed. Some studies reported significant enhancements while others demonstrated minimal or no gains. More seriously, it has been reported that these fossil-based additives might lead to a higher toxicity of the treated wastewaters. Bio-based (biopolymers and biosurfactants) additives might address this toxicity issue; however, the bio-based additives are not always as effective as the fossil-based ones. Despite the beneficial effect, with some exceptions, of additives, the enhancement level varies widely, probably due to the variations in the reaction environment. Thus, to draw meaningful and reliable conclusions on which additive(s) is more promising, thorough studies under unified conditions are needed. Additionally, generation of secondary pollutions associated with the fossil-based additives urges the replacement of such additives with bio-based ones. However, the effectiveness of the bio-based additives is still not sufficiently documented, stressing the need for more in-depth studies.

We analyze Pb content and Pb isotope ratios in 29 surface sediments and one sediment core from the eastern Beibu Gulf, Southern China. The results indicate that obvious Pb enrichment was limited to the oil and gas exploration area in the central gulf and the mud deposit in the northern gulf. The enrichment of Pb in sediment core A97 started in the 1860s, but a notable drop of Pb content occurred in the 1970s, suggesting variations in human activity. The Pb isotope ratios in sediments were very similar to those in natural sources, except for the sediments near the oil platform, which may be polluted by anthropogenic input. Sediments with relatively high radiogenic Pb isotope compositions may be mainly sourced from northern coast of Beibu Gulf, sediment flux through Qiongzhou Strait, or the Red River, while the coastal zone of western Hainan Island and nearby bottom erosion area produce as minor provenances.