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This is the first report on the occurrence of NPPs in the coastal environment. The visual survey is the most common method to quantify and characterize beach litter. However, it is very labor intensive and difficult to carry out on beaches which are remote or difficult to access. We suggest an alternative approach for assessing beach litter using an unmanned aerial vehicle (UAV), or aerial drone, with automated image requisition and processing. Litter of different sizes, colours, and materials were placed randomly on two beaches. Images of beaches with different substrates were obtained by the drone at different operating heights and light conditions and litter on the beaches was identified from the photos by untrained personnel. The quantification of beach litter using the drone was three times faster than that by visual census. This study has demonstrated the potential of using the drone as a cost-effective and an efficient sampling method in routine beach litter monitoring programs. For decades, in response to industrialization and urbanization, environmental qualities of estuarine and coastal areas of the west coast of Korea have been deteriorating. Long-term changes in concentrations of persistent toxic substances (PTSs) in sediments, including PAHs, styrene oligomers, nonylphenols, and metals and their potential toxicities via AhR- and ER-mediated potencies, and bioluminescent bacterial inhibition, were investigated. Long-term monitoring in five estuarine and coastal areas (2010-2018; 10 sites) showed that concentrations of PAHs and nonylphenols in sediments have declined while concentrations of some metals, Cd, Cr, and Hg have increased. Similarly, AhR-mediated potencies in sediments have declined, but inhibitions of bioluminescent bacteria have increased. Concentrations of sedimentary PAHs and AhR-mediated potencies were significantly (p&nbsp; less then &nbsp;0.01) and positively correlated. Sources of PAHs from combustion have been gradually declining while inputs from vehicle exhaust by-products have been increasing. Overall, this study brought our attention a balanced regulation in chemical-specific manner. This study evaluates the geographical distribution of Pb, Cd, Cr, Ni, Co, Cu, Zn, Mn and Fe in wild mussels Mytilus galloprovincialis as well as in associated suspended particulate matter (SPM) and sediments from the Algerian coast. The bioaccumulation (metal concentrations in tissue), bioavailability (metal indices) and bioconcentration of trace metals from the adjacent environment were assessed. The computed pollution load index (PLI) indicates that the sediments are not polluted by these metals, except for Zn which shows a moderate level of contamination. All the metals in SPM samples are in a 'safe range' with respect to the computed degree of contamination (DC&nbsp; less then &nbsp;2). The target hazard quotients (THQ) and the hazard index (HI) values indicate a risk level with Fe. However, the Cr measured in mussels is considered 'extreme', according to the consumption rate limit for mussels (CRlim) which limits their consumption to 0.5&nbsp;kg/day. Mussels (Perna viridis) were collected from the northern coast of the South China Sea (NSCS) to investigate the geographical distribution and potential risk of dichlorodiphenyltrichloroethane and its metabolites (DDTs). DDTs had concentrations that ranged from 248&nbsp;ng/g to 4650&nbsp;ng/g lipid weight (lw), with an average of 807&nbsp;±&nbsp;932&nbsp;ng/ng lw. A comparison of the levels of DDTs in mussels indicated that the NSCS is still one of the most polluted areas in the world, although a decreasing trend was observed. DDT metabolites were predominant in all samples, suggesting that historical residue was the main source of DDT pollution. However, there were new inputs of DDTs which likely associated with antifouling paints. The human health risk assessment revealed that the current concentrations of DDTs in mussels might pose little health risk for the consumers. The influence of upwelling on the phytoplankton community was examined during the upwelling-relaxation period in the southeastern Arabian Sea. Elevated upwelling intensity during the summer monsoon season of 2016 resulted in the re-suspension of harmful dinoflagellates into the surface water. Further, the surplus of phosphorus (P) inputs into the coastal waters from estuarine runoff during the upwelling-relaxation period induced blooming of Gonyaulax polygramma (4.9&nbsp;×&nbsp;106 cells L-1). Results from canonical correspondence analysis revealed that elevated upwelling intensity, P and salinity during the year 2016 likely triggered the bloom of G. polygramma in the study region. HABs like G. polygramma threaten fish stocks such as sardines which have a vital role in the ecosystem. Studies on phytoplankton communities and nutrient dynamics in upwelling systems would be useful in predicting the incidence/toxic effects of harmful algal blooms as these regions have a high potential for fisheries. To evaluate changes in the source of sedimentary organic matter (OM) in the Yellow River estuary, a sediment core collected in eastern Laizhou Bay was analyzed for total organic carbon (TOC), stable carbon isotopes of TOC, and biomarkers. The results showed a decreasing trend in terrestrial OM (TOM), but an increasing trend in marine OM (MOM) over the past 60&nbsp;years. TOM was subdivided into soil OM and plant OM in a three end-member mixing model. The soil OM gradually decreased over the past 60&nbsp;years, with a significant decline since the 1980s, while the plant OM gradually increased. This reveals that the reduction in TOM was caused mainly by the decreased input of soil OM. The reduced TOM contribution can be attributed primarily to dam construction and a decline in precipitation, whereas the elevated MOM contribution was caused by enhanced marine productivity driven by a rise in nutrient inputs. Coastal wetlands of the northern coast of Egypt have been impacted with higher loads of runoff, especially the large urbanized lakes of the Nile deltaic coast. Five urban lakes spanning the northern coast of Egypt (from east to west Bardawil, Manzala, Burullus, Edku, and Mariut) were sampled for quantifying concentrations of heavy metals in their sediment and plant tissues. Sediment and plant tissues in lake Bardawil were the least contaminated, and the other lakes were moderately to highly polluted with Ni, Co, Cr, Pb, Zn, and Cu. Edku had the highest concentrations of Co, Cr, and Cu (19.83, 45.42 and 68.60&nbsp;mg&nbsp;kg-1, respectively). The proportion of clay in sediment was significantly and positively correlated with Co and Ni in sediment (r&nbsp;=&nbsp;0.7 and P&nbsp;≤&nbsp;0.001), suggesting an important role of clay cation exchange capacity in the sorption of metals and removing them from the water column. Anthropogenic debris has been affecting fauna in different ways. We investigate the frequency of anthropogenic material in nests of a brown booby (Sula leucogaster) colony in the Saint Peter and Saint Paul Archipelago (SPSPA), Rio Grande do Norte, Brazil in February 2015 and November 2016. The items were classified according to type (threadlike plastic, sheet plastics, hard fragments, foamed synthetics and miscellaneous) and color. In 2015, a total of 30 anthropogenic items were found in 20.4% of the nests. In nests containing debris, miscellaneous items were found in 73.6% of nests. White/clear was the most common color, 52.6% of nests containing debris had items of this color. In 2016, 45 anthropogenic items were observed in 13.3% of the nests. Threadlike plastic was found in 59.2% of nests. Blue/purple was the most common color (55.5%). Even far from the Brazilian coast, the S. leucogaster colony has been affected by marine pollution. Several large semi-enclosed seas and coastal bodies have formed seasonal hypoxic water masses over large areas. The dominant cause for such formations is believed to be the increasing inflow of nutrients from watersheds and urban areas into estuaries and coastal waters. Several studies have reported hypoxic events in the Pearl River estuary (PRE). However, hypoxia events appear to be episodic, which are neither seasonal nor estuary-wide. The reasons for such occurrences are not understood fully. The objectives of this study are to use 24-year time series data obtained during 1988-2011 to analyze the long-term variability in dissolved oxygen (DO) in summer over the entire estuary from urban areas to estuarine coastal waters and examine regulating factors for the occurrences of hypoxia. The results showed that various regulating factors were responsible for the variability of DO in different regions of the PRE. DO decreased in the urban reach, upstream and main estuarine zones of the PRE from about 2000. It was hypoxic (DO less then 2.0&nbsp;mg&nbsp;L-1) in the urban reach zone and periodic low DO (DO less then 3.5&nbsp;mg&nbsp;L-1) and episodic hypoxic in the upstream zone after 2000, mainly influenced by the increasing sewage discharge. The main estuarine zone experienced episodic low DO and sporadic hypoxia after 2000. The ecosystem buffering capacity was characterized by turbidity, well vertical mixing and short residence time which diluted the pressure for the formation of hypoxia. The eastern shelf appeared to be more vulnerable to hypoxia because of its deeper topography, plume front position, and stratification of the water column compared with the western shelf. [https://www.selleckchem.com/products/gdc-0068.html https://www.selleckchem.com/products/gdc-0068.html] Its bottom waters experienced seasonal low DO but seldom hypoxia. In comparison, low DO rarely occurred in the western shelf because of its shallow topography and short residence time. In brief, 24-year series data captured from 1988 to 2011 showed a lack of seasonal and estuary-wide hypoxia in the PRE. Turkey, with her two important straits, is geographically in the middle of one of the major transportation routes and will continue to face risks the oil tankers pose in those sensitive areas. This paper revisits the site of an oil tanker accident that occurred at the northern entrance of the Istanbul Strait in 1994. The aim of the study was to simulate the same accident in PISCES-II Simulator to compare the response actions of the time with the present capabilities. Effort is also made to understand how the negative impacts of an oil spill accident can be lessened. Therefore, the study is planned to set to cover two separate response scenarios for the identical oil spill incident, actually simulating the 1994 M/T Nassica accident. The results showed that oil pollution response in places with strong currents like Istanbul Strait needs special care to sea conditions as well as related assets. To understand the impact of hydrodynamics on pollutant transport in Laizhou Bay, China, we conducted numerical simulations using Mike 21. The model was calibrated with good agreements to field monitoring data at various monitoring stations. The simulation results show a clockwise and an anti-clockwise tidally-induced residual circulation in the western and eastern bay, respectively. Historical COD monitoring data also indicate two rings of high COD concentration in the same regions of the bay. This suggests that the hydrodynamics of tidal and residual currents is the main cause of the ring-shaped high COD concentration field in the bay. Pollutant inputs from inland rivers are also important for the COD distribution, making the near-shore side of the COD ring higher than the offshore side. Regions with higher retention time in the bay are usually associated with higher COD concentrations. This study is useful in understanding the mechanism of pollutant spatial distribution and subsequent pollution control in a sea bay.