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The scientific assessment and prediction of nearshore water quality are crucial for marine environment protection efforts. This study is based on a comprehensive analysis of existing assessment and prediction methods and considers the regular and random characteristics of nearshore seawater quality due to both natural and anthropogenic influences. It proposes a new method that applies the kriging interpolation algorithm to empirically generated spatio-temporal semivariograms to assess and predict seawater quality. The application of this method in Fujian coastal areas shows that it is able to flexibly and scientifically estimate the variations in various indicators in the region. Combined with GIS spatial data overlay analysis operations, it can be used to quantitatively evaluate different qualities of seawater and provide scientific guidance for marine environmental protection. [ABSTRACT FROM AUTHOR]

The larval development of cowries has remained underexplored due to challenges associated with restricted growth and high mortalities, and as a result, their larvae never achieve competency or metamorphosis. In this study, we conducted a series of experiments using Cypraea tigris larvae to optimise the culture protocols. Broadly, there were no apparent differences in larval survival rates among the seawater quality levels (0.2, 1 aged, 50 μm filtered seawater). In contrast, a microalgal diet solely of Tisochrysis lutea and a mixed diet of Rhodomonas salina + Chaetoceros mulleri had higher larval survival rates than two other mixed diets (i.e., T. lutea + Tetraselmis suecica and T. suecica + R. salina). The provision of 10 ppm of the antibiotic streptomycin sulphate also boosted larval survival by preventing ciliate infection and minimising bacterial growth. We subsequently improved culture protocols by applying new information from these experiments and report the first successful captive breeding of C. tigris through to settlement. The C. tigris larvae reared at 28°C attained competency as early as 40 days post-hatching and metamorphosed by 42 days upon transfer to a well-conditioned tank. Observations of C. tigris larvae and early-stage juvenile development were documented for the first time and are reported herein. [ABSTRACT FROM AUTHOR]

Seawater pollution is highly detrimental to human life and marine biota. Quality of seawater in a particular location also affects fish caught by fishermen. This is the reason why early detection of water conditions is crucial for the preservation of the marine ecosystem with a focus on the measurements of temperature, pH, and salinity. Separate researches have been conducted on the application of sensors and IoT to measure seawater quality as well as fish caller device to increase the possibility of catching fish. Therefore, this research has been used to integrate both devices in order to ensure fishermen contribute to the provision of information on seawater quality while catching fish by using fish caller device. This has been achieved through the implementation of NodeMCU ESP8266 to control frequency of fish caller device as well as to assess the parameters of seawater quality. Moreover, data obtained from the sensors have been first stored in a microSD card in order to overcome the lack of internet connectivity at the location and automatically sent to the server once the NodeMCU established an internet connection. An Android smartphone application has been used to select frequency of fish caller device according to the desired fish species as well as to view the seawater quality data stored on the server. This effort is directed at ensuring that an integrated system is developed to increase frequency of catching fish using fish caller device while contributing to the process of monitoring seawater quality, which is crucial for the preservation of the marine ecosystem. [ABSTRACT FROM AUTHOR]

In the field of chemical engineering and water treatment, the study of viruses, included surrogates, is well documented. Often, surrogates are used to study viruses and their behavior because they can be produced in larger quantities in safer conditions and are easier to handle. In fact, surrogates allow studying microorganisms which are non-infectious to humans but share some properties similar to pathogenic viruses: structure, composition, morphology, and size. Human noroviruses, recognized as the leading cause of epidemics and sporadic cases of gastroenteritis across all age groups, may be mimicked by the Tulane virus. The objectives of this work were to study (i) the ultrafiltration of Tulane virus and norovirus to validate that Tulane virus can be used as a surrogate for norovirus in water treatment process and (ii) the retention of norovirus and the surrogate as a function of water quality to better understand the use of the latter pathogenic viruses. Ultrafiltration tests showed significant logarithmic reduction values (LRV) in viral RNA: around 2.5 for global LRV (i.e., based on the initial and permeate average concentrations) and between 2 and 6 for average LRV (i.e., retention rate considering the increase of viral concentration in the retentate), both for norovirus and the surrogate Tulane virus. Higher reduction rates (from 2 to 6 log genome copies) are obtained for higher initial concentrations (from 101 to 107 genome copies per mL) due to virus aggregation in membrane lumen. Tulane virus appears to be a good surrogate for norovirus retention by membrane processes. [ABSTRACT FROM AUTHOR]

This article, titled "Editorial: Coastal environmental quality and marine biodiversity assessment, volume II," emphasizes the importance of monitoring and addressing coastal pollution to ensure the sustainability of coastal and marine ecosystems. The release of contaminants from human activities has led to the deterioration of seawater and sediment quality in coastal areas. The article highlights the need for regular monitoring of physical, chemical, and biological characteristics of seawater and sediment to develop plans for mitigating pollution and promoting healthy habitats for plants and animals. It also discusses the impact of pollutants on the coastal and marine ecosystem, including trace metals and eutrophication, and the role of phytoplankton in primary production patterns. The article further explores the impact of eutrophication and organic pollution on phytoplankton abundances in coastal aquatic systems and the role of microorganisms in seawater and biogeochemical processes. The study also examines the composition and diversity of deep-sea bacterial communities and the factors influencing prokaryotic communities in the Korea Strait. The findings highlight the need for further research on water masses, climate change, and their effects on marine ecosystems. [Extracted from the article]

The assessment of seawater quality is a complex process as it involves the influence of several factors and is characterized by dynamic changes in these factors. Herein, a novel model coupled with the semi-partial subtraction set pair potential method (SSSPP) and game theory was discussed for the dynamic assessment of seawater quality. In the proposed model, the identity–discrepancy–contrary degrees were calculated to construct the evaluation matrix, and then the classification and the dynamic risk trends of the seawater quality were determined. A case study and comparison with the single-factor approach and Nemerow index evaluation method were carried out to confirm the accuracy and dependability of the suggested model. The results indicate that the proposed method can be used to measure trends in seawater quality evolution and also to diagnose key indicators affecting seawater quality. It provides a new and effective way to accurately identify the quality of seawater and its trends. [ABSTRACT FROM AUTHOR]

Outbreaks of crown-of-thorn starfish (COTS) have caused dramatic declines in reefs through predation on corals, but the post-bloom effects of COTS may still potentially threaten the environment and living organisms due to massive organic decomposition. This stimulation experiment showed that the decomposition of COTS debris triggered an extra mineralization process and resulted in acidifying, hypoxic, and eutrophic seawater. Consequently, the photosynthetic efficiency of coral symbionts decreased by 83%, and coral bleached after removing the stress within two days, then the coral skeleton dissolved at rates of 0.02–0.05 mg cm−2 day−1. Within two weeks, the photosynthesis and growth of benthic algae were suppressed by 27–86% and 1.5–16%, respectively. The mortality of turf algae and coralline algae indicated compromised primary productivity and limited coral recruitment, respectively. However, macroalgae, as coral competitors, became the only survivors, with increasing chlorophyll content. This study suggests a continuing decline of reefs during the collapse phase of COTS outbreaks and highlights the need for improving control strategies for the COTS population. [ABSTRACT FROM AUTHOR]

The development of coastal truism in Albania during the last decade has had a huge impact on the seawater quality. As a result, it is shown that the recreative water quality is affected sometimes by the presence of different types of microorganisms, some of them potential pathogens for humans. This study has the main focus on the assessment of the seawater in the bathing site of Zvërnec Beach in Vlore Albania. The examination of the seawater is based on the evaluation of the microbiological indicators such as total coliforms and E coli and also the physical-chemical parameters like pH, temperature, conductivity, DO, and salinity. The study was conducted over eight months from June 2022 to January 2023. The samples were collected in six different sites and have been analyzed for both microbial and physic-chemical parameters. The method for the fecal bacteria assessment is the standard technique of MPN. The results show that one station has large values of bacterial pollution, and there is a correlation between fecal contamination and temperature. Every station displays seasonal differences, during summer there is a higher contamination, compared with winter. Therefore, seawater monitoring of microbiological elements must be performed continuously in all the coastal areas of Vlora City. [ABSTRACT FROM AUTHOR]

Mariculture can provide a large amount of food without occupying land resources, which provides important assistance for humans to achieve sustainable development. In this paper, China, where the output of mariculture exceeds half of the global output, is taken as the research area. Based on the spatial distribution data of three periods of mariculture along the coast of the Chinese Mainland in 2000, 2010, and 2020 obtained from remote sensing images and from the perspective of the mariculture center, the spatial development of mariculture in three periods in China is explored. Furthermore, by spatially overlaying mariculture data with concurrent water quality data, the relationship between the development and changes in the mariculture center and the seawater quality in different geographical environments was analyzed at the national scale.. We found that (1) Mariculture in China exhibits a noticeable geographical differentiation, with the scale and development speed of mariculture in northern regions surpassing that of the southern regions. (2) Good seawater quality is the prerequisite for the formation of mariculture centers, while water quality deterioration is detrimental to the development of mariculture. (3) The formation of large-scale high-density mariculture centers does not necessarily lead to deterioration of the seawater quality. Furthermore, we found that the water depth is an important factor leading to the spatial distribution pattern of mariculture in China, i.e., dense in the north and sparse in the south. The flow velocity is an important factor determining the water quality changes in mariculture centers.

To ensure the environment-friendly and ecological safety of seawater pumped storage power station (SPSPS) operation, the effect of chemical oxygen demand (COD) discharged by a proposed SPSPS on the surrounding marine environment was simulated and investigated in this paper, which was based on the monitoring and analysis of seawater quality in the Dawanshan island as an example. The results showed that the seawater quality surrounding the Dawanshan island was good with the COD value less than 0.2 mg/L. When the COD concentration was less than 50 mg/L in the effluent of SPSPS, the maximum COD concentration reached 2.29 mg/L in the surrounding seawater, which could still satisfy the requirement of the seawater quality. However, when the COD concentration was higher than 100 mg/L in the effluent of SPSPS, the risk of exceeding the seawater standard was high in the surrounding seawater. The discharge of COD was affected by the seawater temperature and tide, and fluctuated in terms of concentration, diffusion direction and gather location in the surrounding seawater according to the season change. The maximum COD concentration would increase with the water discharge increasing from the SPSPS into the surrounding seawater. The distance between the location of the maximum COD concentration in the surrounding seawater and the outfall of SPSPS was about 1.6 km. The results would provide a scientific basis for controlling the COD pollution from the discharge of SPSPS.

In order to strengthen the mastery of the water environment quality of key sea areas and protect the marine ecological environment, based on the monitoring results of 24 stations, this paper evaluated the water environment quality of Luanhe estuary-Beidaihe sea area from 2015 to 2019 by integrating the evaluation methods of single factor pollution index method, eutrophication index method and organic pollution evaluation index method. The results showed that the overall water quality in the study area was good. Inorganic nitrogen, active phosphate and chemical oxygen demand exceed the standard in varying degrees, but most stations met the class Ⅰ seawater quality standard. In 2015 and 2018, individual stations at the estuary were in eutrophic state, and other years and stations were in oligotrophic state. Except for individual stations near the shore and estuary, the seawater was not organically polluted, the water quality was in about good or good condition, and there was a trend of continuous development.

Coastal zones are critically important ecosystems that are closely tied to human activities, such as tourism, urbanization, transport, and aquaculture. However, managing and monitoring sea water in the coastal areas is often challenging due to the diversity of the pollution sources. Traditional approaches of onsite measurement and surveys have limitations in terms of cost, efficiency and productivity compared with modern remote sensing methods, particularly for larger and longer observations. Optical remote sensing imagery has been proven to be a good data source for water quality assessment in general and for seawater studies in particular with the use of advanced techniques of data processing such as machine learning (ML) algorithms. However, optical remote sensing data also have their own disadvantages as they are much affected by climatic conditions, atmospheric gas and particles as a source of noise in the data. This noise could be reduced, but it is still unavoidable. This study aims to model seawater quality parameters (total suspended solids (TSS), chlorophyll-a (chla), chemical oxygen demand (COD), and dissolved oxygen (DO)) along a 134 km sea coastal area of the Binh Dinh province by applying the current robust machine learning models of decision tree (DT), random forest (RF), gradient boosting regression (GBR), and Ada boost regression (ABR) using Sentinel-2 imagery. To reduce the atmospheric effects, we conducted onsite measurements of sea surface reflectance (SSR) using the German RAMSES-TriOS instrument for calibration of the Sentinel-2 level 2A data before inputting them to the ML models. Our modeling results showed an improvement of the model accuracy using calibrated SSR compared with the original Sentinel-2 level 2A SSR data. The RF predicted the most accurate seawater quality parameters compared with in situ field-measured data (mean R2 = 0.59 using original Sentinel-2 level 2A SSR and R2 = 0.70 using calibrated SSR). The chla was the most precise estimate (R2 = 0.74 when modelled by the RF model) flowing by DO, COD and TSS. In terms of seawater quality estimation, this accuracy is at a good level. The results of the seawater quality distributions were strongly correlated with coastal features where higher values of TSS, chla, COD, and DO are near the river mouths and urban and tourist areas. These spatial water quality data could be extremely helpful for local governments to make decisions when the modelling is continuously conducted (using big data processing), and it is highly recommended for more applications. [ABSTRACT FROM AUTHOR]

Coastal tourism has a great role in the Albanian economy. In recent years, there has been an increase in public awareness regarding seawater quality. Beach water quality is affected by a point source (such as sewage outfalls) and a non-point source of contamination (such as stormwater runoff, sand resuspension, animal fecal inputs, and human bather shedding). Contaminated seawater could cause several health consequences for beach users. International regulations usually assess water quality by the quantification of fecal indicator bacteria. This study aimed to evaluate the seawater quality in eight beaches along the Southern Adriatic. Settings and Design: The, microbiological and physic-chemical analysis of recreation seawater. Water samples were taken monthly from January to December 2021 in eight stations and eventually distributed on this coastline. Methods and Material: Fecal bacteria is determined using MPN techniques and EC media, while physic-chemical parameters were estimated using standard methods. Results: High values of coliform bacteria were observed in four sampling stations, beaches classified as: urban, near harbors, and delta river. Conclusions: According to the obtained data, monitoring programs have to be focused especially in urban areas and in tourist beach sites. This could enhance microbiological water quality and consequently, beachgoer’s safety and touristic beach attractiveness to international visitors. [ABSTRACT FROM AUTHOR]

The purpose of the paper was to create databases that would allow a proper assessment of the degree of marine pollution generated by shipyard industrial sector. The study was conducted over a period of three years, between 2015 and 2017. The parameters determined for the waters collected from the shipyard were within the maximum allowed limits according to the norms in force. However, values very close to the maximum allowable limit were observed in the case of groundwater for nickel, determined from the drilling located near the fuel depot in 2015 and chlorides determined from the drilling located near the galvanizing workshop, both in 2016 and in 2017. The analyzed parameters for the soil samples, collected from various sampling points and different depths, were below the value of the alert thresholds for less sensitive soils, according to Order 756/97. The databases created for this study can contribute as an incipient basis for the development of larger studies that include other industrial sectors as well as a longer evaluation period.

The transport of live fish for aquaculture is a key issue in the domestication of new species. National level programs were developed in Peru for controlled repopulation of Peruvian grunt (Anisotremus scapularis), reared in extensive systems or ongrown in floating cages, but these were limited by inadequate knowledge of the best transport parameters to ensure survival. This study aims to identify the effect of low‐density (21.18 ± 4.38) medium (31.77 ± 6.57) and high‐density in (42.36 ± 8.76 kg m−3), corresponding to 6 (48), 9 (72), and 12 (96 ind·bag−1) ind·L−1 during the transport time (8, 10, and 12 hr), on survival. Also seawater temperature, dissolved oxygen, pH, ammoniacal nitrogen (NH3N), ammonia (NH3), and ammonium (NH4) were recorded at the end of transport. Survival at 8 and 10 hr at low‐density was similar, but decreased at 12 hr. In contrast, all densities showed a greater effect after 12 hr of transport with 61.11 ± 17.35; 67.13 ± 7.13, and 70.49 ± 4.70% survival, respectively. Finally, the influence of the variables analyzed to contribute to survival and the sum of these, plus other parameters that were not measured, such as stress, leads to the conclusion of between 8 and 10 hr of transport time and not exceeding stocking density of 72 ind/bag (31.77 ± 6.57 kg m−3) should be used. [ABSTRACT FROM AUTHOR]

A monitoring program of seawater quality was conducted during the October 2013–June 2016 period at the port city of Patras. A total of fourteen sampling campaigns were conducted. Eleven sampling sites were selected at the Southern New Port and at the Northern Old Port of Patras, namely at the discharge point of the south outlet of the collecting storm water conduit and at the two river mouths discharging at both sides of the Southern New Port, to evaluate the contribution of surface runoff and harbor activities on seawater pollution. At each site, water quality parameters were determined in situ, and water samples were transferred and analyzed at the laboratory. Taking into consideration the whole set of measurements, it can be concluded that the seawater quality of the two ports is satisfactory in comparison to other coastal zones in the area around Patras and other ports.

The Red Sea coastal environment of Halayeb and Shalateen area is renowned for its abundant marine flora and fauna. It also holds significant economic and cultural importance for local communities. However, this region is currently confronted with various challenges, including climate change and habitat destruction. To effectively address and mitigate these issues, advanced technologies that offer a holistic understanding of the area's environmental conditions are required. This paper applies the integration of Geospatial Artificial Intelligence (GeoAI) and ChatGPT to study the Red Sea Coastal water quality dynamics of Halayeb and Shalateen Area. Landsat imagery and Copernicus Marine Service were used to retrieve area boundaries and monitor the physicochemical characteristics of the coastal water respectively. ChatGPT was utilized to generate Python code that facilitates the creation of optimal distribution maps for each physical and chemical property criterion. The Python codes were incorporated into the Python program within the ArcGIS 10.7.1 and executed to generate the desired maps representing the dynamics of physical and chemical properties. It was found an observed fluctuation in chemical properties next to the coastline around the mouth of two main wadies; Wadi Hudain, and Wadi Da'eb. The degree of stability increased away from the coast toward the deep water. That proved the effect of the runoff on the seawater, as the runoff plays an essential role in the water state, especially in such semi-closed water bodies like the Red Sea where the flashfloods are the main source that can enrich water with sediment and nutrients. The state of seawater in terms of physical properties was not characterized by a specific pattern. The distribution of physical parameters in the Red Sea is influenced by factors such as regional climate variations, monsoonal winds, and local topography. This paper serves as a stepping stone for future research endeavors, exploring the full potential of this integrated approach. It can be concluded that the fusion of GeoAI and ChatGPT technologies has the potential to revolutionize our approach to studying and managing the coastal environment. [ABSTRACT FROM AUTHOR]

The polyculture of shellfish and seaweed together is an effective way to solve the current bottleneck in developing the shellfish culture industry, and determining the optimal ratio is an important prerequisite for its application. Large-scale oyster monocultures in the Beibu Gulf (South China) have led to environmental degradation and exceeded the aquaculture carrying capacity. In order to cope with the problem, this study designed a microcosm of polyculture with shellfish and seaweed, trying to explore the optimal ratio with both environmental protection and economic benefits. Different densities of Gracilaria tenuistipitata (0.33–4.17 kg/m3 ) combined with a fixed density (83.3 ind/m3 ) of Crassostrea hongkongensis were investigated to measure the growth rate and nutrient removal effects. The oyster growth rates in the polyculture groups were 6–14-fold that of the oysters in the monoculture group. The highest oyster and seaweed growth rates were in the medium-density seaweed group (0.83 kg/m3 ). Compared with the low-density seaweed groups, a high density of seaweed effectively removed the nutrients released by the oysters. A response surface analysis showed that a seaweed density of 1.567 kg/m3 was the optimal proportion with 83.3 ind/m3 (10 individuals) of C. hongkongensis, with a predicted growth rate of 0.110%/day for the oyster and 0.564%/day for the seaweed. This research indicates that combining G. tenuistipitata in a polyculture system could increase oyster production and provide the exciting prospect of improving seawater quality in the Beibu Gulf. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the relationships between atmospheric parameters, seawater quality and green mussel production which were cultured in pond, estuary and coastal areas. Seawater and mussel samples were collected from mussel farms in the inner Gulf of Thailand from January to December 2019. Climate data were obtained from the Thai Meteorological Department. The correlations between selected atmospheric and seawater parameters were developed using linear and non-linear models. The influence of seawater quality on mussel production was evaluated using principal component analysis and stepwise multiple linear regression. The effects of atmospheric variation on green mussel productivity were simulated. The results showed that high air temperature and rainfall caused an increase in seawater temperature and a decrease in salinity, respectively. It was observed that the most influential factors affecting mussel production were nutrients and dissolved oxygen in ponds, temperature and salinity in estuaries, and nutrients and pH in coastal areas. The simulation indicated that mussel production can deteriorate when air temperature reaches 34°C and rainfall is higher than 200 mm per month. Our results suggest that under climate change events, locations with less riverine influence can provide higher mussel productivity. These results can be used as a guideline for farmers during a climate change event.

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Coliform bacteria (CB) can be used as an indicator of seawater quality. Long-term monitoring of seawater quality based on CB abundance is lacking in Jiaozhou Bay. In this study, CB abundance in surface seawater of 12 different stations in Jiaozhou Bay was investigated by culturing method. The results showed that: (1) the abundance of CB showed a decreasing tendency during the investigation. During 2004–2007, 2008–2013, and 2014–2017, the average CB abundance decreased significantly, forming a “three stages phenomenon”; (2) the average CB abundance in the first half of the year was lower than that in the second half; (3) the CB abundance in Jiaozhou Bay was spatially heterogeneous. The maximum average CB abundance was observed in the estuary area, and followed by the bay mouth area, the outer bay area, and the inner bay area. The highest abundance may be associated with sewage discharge related to human activities; (4) the abundance of CB was most positively correlated with the concentration of ammonium salt and nitrate, while most negatively correlated with salinity; (5) the years 2007 (2008) and 2013 (2014) were time points of the “three stages phenomenon.” These time points coincide with environmental governance actions, indicating that the actions have played a prominent role in improving seawater quality. Long-term survey of CB can not only serve as an indicator of seawater quality, but also provide a basis for the development of environmental governance strategies and pollution control.

A method of assessing the quality of seawater using the rotifer Brachionus plicatilis Müller is described. Relevance of developing a new bioassay of marine aquatic environment is emphasized, and the choice of the saltwater rotifer B. plicatilis as a test organism is justified considering its biological characteristics, specific structural features, reproduction, and development. A detailed protocol of maintaining rotifer cultures under laboratory conditions is presented, including feeding, breeding, and testing their sensitivity to standard toxicants; the list of necessary materials, reagents, and equipment is provided, and the procedures of biotesting and assessing seawater quality are described. Application of this bioassay is illustrated on several samples of seawater contaminated with heavy metals (copper and zinc) and organic compounds (ethanol and isopropanol). Some specific features of chronic and acute seawater pollution were determined. In particular, continuous contamination with a small concentration of a toxic substance and short-term exposure to high concentrations of pollutants can have different consequences. The results of the bioassay substantiate the need for laboratory experiments simulating different modes of contamination of aquatic environments with toxic pollutants. [ABSTRACT FROM AUTHOR]

The study provides an assessment of sand dredging activities from the bottom of the sea during 2016 in the Kingdom of Bahrain. Total Suspended Solids were analyzed from 2010 until 2016 in the northern and eastern locations according to the Manual of oceanographic observations and pollutant analyses methods. Fifty five percent of sand dredging companies complied with some legislation such as air quality and occupational health. Almost all lacked any compliancy evidence supporting environmental protection. Only 9% of these sand companies use siltation processes to the dredged materials. Siltation is an important step to avoid dispersion of sand into the marine environment. Ambient Total Suspended Solids was around 6.1 mgl−1 ± Standard Error and the study recommends 10 mgl−1 level as an accepted concentration in samples taken from 500 meters away from the dredgers and 100 mgl−1 in samples taken from the middle of the generated silt plumes. The effect of climatic temperatures, dust storms and rain levels on seawater Total Suspended Solids concentration has been briefly discussed. The study concludes no significance seasonal or spatial variation on the ambient Total Suspended Solids concentration. It recommends coupling remote sensing with the conventional data collection and integration of modelling efforts for effective cost benefit monitoring and management of the coastal waters. [ABSTRACT FROM AUTHOR]

Southern Taiwan’s Kenting National Park is a popular retreating place for many domestic and international tourists, with increasing tourist numbers potentially over-burdening the coastal ecosystems. To better understand human impacts, a long-term ecological research program was initiated in 2001 to track water quality at 14 coral reef-abutting sites throughout the park since then. Extracting the data from this 20-year survey, we found that increasing in the nutrient levels during the summer rainy season, together with the drops in salinity led by freshwater inputs (land- & rainfall-derived), was the main impact to coral reef ecosystem of Kenting. Cluster analysis further confirmed the nutrient influx was mainly attributed to the local discharge outlets with dense of villages and hotels at upstream. Therefore, more efforts are needed to input to control tourist number, treat waste water discharge and strengthen land protection facilities.

With the development of marine resources and human activities along the coast, seawater pollution has become a crucial topic. Monitoring and evaluation of seawater quality is an important reference for human to understand the marine ecological environment. This paper uses the T-S fuzzy neural network to evaluate the quality of seawater in Hangzhou Bay. The result shows that the water quality in Hangzhou Bay is at a poor level. This conclusion is consistent with the result of the Official Report of China Offshore Quality. [ABSTRACT FROM AUTHOR]

Objective: It has been shown that the incidence of gastrointestinal disease caused by gastrointestinal contamination with recreational waters correlates with the level of fecal indicator bacteria (FIB) in the water. The purpose of the study is to evaluate the results of microbiological analysis of seawater samples taken during the summer season of 2016 from the Atakum coasts of Samsun province and to evaluate the conformity of the results with respect to FIB levels and to propose the bathing water profile of these beaches. Methods: The microbiological results of 268 samples taken from 17 sampling points on the coast of Samsun -Atakum District of June-September 2016 were included in the study. Beaches in Atakum District are coded alphabetically with random letters. The data are expressed in median (minimum - maximum) values. All data were evaluated according to the criteria of "Swimming Water Quality Regulation". Results: In the study, 804 results of 268 samples taken from 17 points were evaluated. According to the related regulation, it is determined that there are no data exceeding the mandatory value but 14 (5%) data exceeding the guide value. Conclusion: It has been determined that sea water quality grade at all sampling points on the Atakum coast is "A". [ABSTRACT FROM AUTHOR]

The quality of seawater needs to be continuously monitored due to its effect on human life and natural ecosystems. However, the balance of the extent, spatial pattern and maintenance costs of marine environmental monitoring remains a challenging issue which is crucial for decision-makers. The main contribution of this work suggests taking advantage of two minimization criteria (TMC: integrating minimization of Kriging variance and minimization of relative error at a given confidence level) to improve the design and optimization of a marine environmental monitoring network. To achieve this purpose, the spatial simulated annealing (SSA) method is applied to identify the best locations for monitoring network optimization. For the case study, phosphate (PO 4) is used as an indicator to characterize the seawater quality in northern coastal waters of Zhejiang Province, China. The 122 existing sites have redundancies (about 78 sites) that can be effectively identified and removed to reduce costs with the given relative error (less than 10%) and confidence level (95%). Some new sites can be added and adjusted to improve the quality of costal environmental monitoring based on quantitative analysis. In addition, the relationship between the number of the monitoring sites and monitoring precision is analyzed. The results suggest that the present method using TMC can provide a scientific basis for marine environmental monitoring and management. • A method integrating statistical and geostatistical approaches was presented. • The two minimization criteria will help to quantitatively design monitoring sites. • Phosphate can be used as an indicator to evaluate and optimize monitoring networks. • The presented method successfully optimized the minimum number of monitoring sites. [ABSTRACT FROM AUTHOR]

Abstract This paper builds an environmental Kuznets curve (EKC) multiple logistic regression model to analyze how socio-economic development impacts mainland China's coastal waters environment. China's coastal provinces have significantly different seawater quality at different stages of the seawater's EKC. Jiangsu and Hebei are still at the early stage of the seawater's EKC because of the large quantity of pollution-intensive industry, whereas the coastal provinces at the late stage of the seawater's EKC have presented obviously improved seawater quality based on adjustments in the industrial structure since 2001. Urbanization has a severe impact on the seawater quality of Shanghai and Zhejiang at the middle stage of the seawater's EKC. Furthermore, this paper proposes an overall strategy and several "tailored" strategies to address coastal waters environment improvement for current poorly targeted policies at different stages of the seawater's EKC. [ABSTRACT FROM AUTHOR]

This study reports a preliminary survey of salinity variations and trace element concentrations in seawater collected from the coastal areas of Qatar. The concentrations of trace elements in seawater were determined by inductively coupled plasma atomic emission spectroscopy. The concentrations of trace elements were less than 5 ppb for As, Cd, V, Ag, Cr, Mn, Co, Ni, Be, Cu, Tl, and Sn; less than 15 ppb for Pb, Zn, Fe, and Se; less than 50 ppb for Sb, Al, and Ba; and less than 15 ppm for Si, Sr, and B. The average salinities of eastern and western coasts were 42 and 51 ppt, respectively. This salinity variation across the coastal regions is due to the marginal enclosed nature of the sea and brine discharge from desalination plants of the Gulf region. Among analyzed elements, Al, Ba, Fe, Zn, Sb, and Pb were significantly higher at some specific locations than their general average concentrations in the region. These site-specific variations in trace element concentrations may be related to anthropogenic inputs from industrial activities. Strong correlations were obtained for Al–Fe, Sb–Pb, and Sr–B combinations confirming their coexistence from common pollution sources. The trace element average concentrations in Qatari seawater are within the national and environmental protection agency seawater quality standards, they and exhibited similar concentrations to that of Red Sea. Outcomes of this study can be applied to mitigate pollution, improve water management efficiencies and assist sustainable operations of desalination plants. [ABSTRACT FROM AUTHOR]

Since 2013, there has been an increase (>23%) in naval traffic using maritime routes and ports on the coastal fringe of Santa Marta, Colombia. Of major concern, and described by several studies, is the relationship between maritime traffic and coastal contamination. This study proposed a maritime traffic indicator considering the simultaneous effects of several relevant measurements of water quality parameters to estimate the impact of naval activity. The approach involved developing a model including the number of vessels, hull length, and permanence time in berths. In addition, water quality variables, considering climatic seasons, were used to verify association with maritime traffic and touristic activities. The high concentrations of total coliforms (TC) and dissolved/dispersed petroleum hydrocarbons in chrysene equivalents (DDPH) reported by the International Marina of Santa Marta (SM) were affected by the local anthropic activities, including tourism, naval traffic, and urban wastewater discharges. Moreover, our results suggest the occurrence of multiple chemical impacts within Tayrona National Natural Park (PNNT) affecting conservation goals. The estimation of the maritime traffic indicator proposed in this study may be an easy and more complete tool for future studies evaluating the impact of naval activities on environmental quality.

Many coastal cities in the world have adopted submarine outfall as the solution for their sewage disposal. Brazil, a country with a coastline of 7,500 km, or quite more if one includes the perimeters of bays, has had a good experience with submarine outfalls for sewage disposal. It has proved to be a safe and economical solution to keep coastal waters to meet quality standards. The paper covers aspects such as bathing standards, legislation, refers to the main outfalls in Brazil, suggested pretreatment, and trends in the outfall design.

The aim of the study was to evaluate the impact of potential pollution sources, mainly from the upstream anthropogenic sources and port-related activities. The in-vestigated area covered a wide range of anthropogenic im-pacts (e.g., industrial wastes, storm water runoff, acciden-tal oil spills, intentional discharges and shipping activities). The quality of water and Sediments was assessed us-ing Standard methods, as physical-chemical parameters, chemistry and biology (microbiology, ecotoxicology) aim-ing to figure the level of pollution and the effect of port-related activities. Seawater quality results agreed generally with environmental Standards. Though, in some samples the concentrations of sulphates (mg/1) and heavy metals (μg/1), as B, As and Se exceeded the recommended lim-its, without posing a serious environmental concern. Most of the surface sediment samples contain critical levels of hydrocarbons (C>12), (mg/kg), polycyclic aromatic hydrocarbons (ng/g) and polychlorobiphenyls (ng/g). For some heavy metals (mg/kg), exchangeable concentrations were found to be very close or above the regulations. The signifi-cance of this study is incontestable taking into account the lack of previous relevant historical data of this area. In this sense, it was possible to indicate, in general, good environmental conditions, despite the industrial and concentrated local port-related activities in the investigated area.

Beach water quality is an important factor concerning public health and tourism linked to the “Sun, Sea and Sand” market and is usually assessed in international regulations by the quantification of Escherichia coli and enterococci counts. Despite Salmonella spp. detection not being included in international normative, the presence/absence of this bacteria is also an indicator of seawater quality. The objective of this study was to determine microbiological quality of beach water at 14 beaches along the Department of Atlántico (Colombia) and its relationship with beach characteristics as beach typology (i.e., urban, village, rural and remote areas), presence of beach facilities (e.g., bars, restaurants, etc.) and streams outflowing into the coastline. Sampling program aimed to analyse E. coli and Salmonella spp., by culture-based and real time PCR methods, respectively. Microbiological outcomes were compared with beach characteristics, and a cluster analysis was performed. E. coli and Salmonella spp. were detected in 70% and 20% of samples, respectively. Highest E. coli counts were observed at beaches classified as urban and at Sabanilla, a rural beach with presence of numerous beach restaurants/bars. Salmonella spp. presence was associated with streams that lack wastewater treatment systems. Cluster analysis clearly evidenced the relationship between E. coli and Salmonella spp. and beach characteristics, allowing to obtain indications to implement management programs. According to data obtained, monitoring programs have to be especially carried out in urban areas and at places with beach facilities. This could enhance microbiological water quality and consequently, beachgoers safety and touristic beach attractiveness to international visitors.

Abstract Andaman and Nicobar islands is one of the major tourism hubs of the World. Most travelers visit these islands for historical attractions, beaches, snorkeling, scuba diving, coral reefs, adventure and recreation. Port Blair is the capital and sole entry/exit point of these islands. The coasts of Port Blair Bay (PBB) and Wandoor Creek (WC) are largely populated due to its services offered to different public/private sectors and for the economic significance. Nevertheless, the global recognition of these islands relies on its healthy ecosystem. Effective management of beaches, bays and their environmental services requires knowledge of coastal water quality. This study assesses the datasets of twenty seawater quality parameters of PBB and WC generated during five years (2011–2015) at eight sites. Multivariate statistical techniques were used for (i) analysis and interpretation of water quality parameters (ii) identification of pollution factors/sources and (iii) understanding spatio-temporal variations valuable for coastal water quality management. Graphical abstract Unlabelled Image Highlights • Half-decade seawater quality datasets were evaluated via multivariate statistical analysis. • Assessment of long-term data aids to understand and establish spatial/temporal patterns. • Results identified the key parameters and characteristics responsible for seawater quality. • Investigation of intricate datasets facilitates future projected activities for ecosystem management. [ABSTRACT FROM AUTHOR]

The post-depositional geochemical behaviour of mercury and arsenic in submarine mine tailings from the Mesel Gold Mine in Buyat Bay, North Sulawesi, Indonesia was assessed by in situ sampling of tailings porewaters using dialysis arrays and seawater and fish monitoring. Under steady-state conditions one year after cessation of tailings discharge, the calculated arsenic efflux incrementally added 0.8 μg/L of arsenic to the overlying seawater. The mercury efflux across the tailings-seawater interface was negligible. The arsenic and mercury concentration in seawater bottom samples monitored biannually during a 9-year post-closure program were 1.54 μg/L and <0.05 μg/L, respectively. Analysis of 650 fish tissue samples, from the post-closure monitoring had mean mercury and arsenic concentrations consistently below the FAO/WHO CODEX, and Australian and New Zealand National Food Standards, respectively. The results of the porewater, seawater and fish tissue demonstrate that the arsenic and mercury-bearing bearing compounds in the tailings are geochemically stable. [ABSTRACT FROM AUTHOR]

Characterization of seawater quality is crucial to determine the selection and design of pretreatment process as well as to manage membrane fouling in seawater reverse osmosis (SWRO) plants. In some cases, conventional seawater quality parameters are limited in explaining the regional variations of raw seawater and/or in predicting the extent of membrane fouling because of poor correlations between the amounts of impurities in seawater and the resultant membrane fouling. In this study, four seawater quality parameters (P-MFI, C-MFI, PROTEIN and HUMIC) are newly employed to investigate whether those parameters could overcome the current limitations of conventional parameters. Seawater samples have been collected periodically from five different SWRO plants and then analyzed by multiple membrane array system to obtain the two different MFI values and by fluorescence spectrophotometer for PROTEIN and HUMIC quantifications. Statistical analyses of seawater quality data from the SWRO plants showing the different extent of membrane fouling suggest that those parameters are useful to estimate membrane fouling by all types of impurities such as particles, colloids and organic matters in seawater. In addition, the four suggested parameters (P-MFI, C-MFI, PROTEIN and HUMIC) could better specify the regional differences of seawater quality and the changes of impurities from raw seawater to RO feedwater according to operating conditions, which would be the basis to establish the practical guidelines for a pretreatment design and an efficient operation of SWRO plants. [ABSTRACT FROM AUTHOR]

Data are reported for an inland artificial lagoon (Ayla) to evaluate the impact of the lagoon’s modeled design and water replenishment system on its water quality and the coastal ecosystem. This study focused on Ayla’s upper lagoon (UL) only, due to its isolation from the two other lagoons and the ambient seawater in the Gulf of Aqaba (GoA). Nutrient measurements (nitrite, nitrate, ammonium, phosphate, and silicate) in addition to Chlorophyll a (Chl a) data were collected between July 2012 and June 2013. Chl a values in the UL were not significantly different from ambient seawater in the GoA, and the UL did not show seasonal differences (p = 0.456). Significant variability for nitrite was observed in the UL between spring and summer (p < 0.0001) and between fall and winter (p < 0.0001). Nitrite showed a stronger seasonal effect in the GoA seawater than in the UL (p = 0.056). Phosphorus showed a seasonal effect and remained similar between the UL and GoA. Nutrient stoichiometry showed a Redfield-like nitrogen-to-phosphorus (N:P) ratio for the ambient GoA seawater around the inlet pumping source and an increased N:P ratio inside the UL. This study emphasizes the importance of modeled lagoon design and seawater replenishment system in preventing and inhibiting eutrophication of the lagoon and therefore minimizing contamination in the coastal ecosystem.

This work carries out a landscape analysis for the last 60 years to compare the degree of preservation of two areas on the same Italian coastline characterized by different environmental protection levels: a National designated protected areas and a highly tourist coastal destination. The conversion of natural land-covers into human land uses were detected for protected and unprotected coastal stretches highlighting that the only establishment of a protected area is not enough to stem undesirable land-use outcomes. A survey analysis was also conducted to assess attitudes of beach users and to evaluate their perception of natural habitats, beach and coastal water quality, and coastal dynamic over time. The results of 2071 questionnaires showed that there is similarity between subjective and objective data. However, several beach users perceived a bad quality of coastal water in the legally unprotected coastal area. The implications from a planning and management perspective are discussed. [ABSTRACT FROM AUTHOR]

Chlorophyll a (Chl a) is the predominant pigment in every single photosynthesizing organism including phytoplankton and one of the most commonly measured water quality parameters. Various methods are available for Chl a analysis, but the majority of them are of limited throughput and require considerable effort and time from the operator. The present study describes a high-throughput, microplate-based fluorometric assay for rapid quantification of Chl a in phytoplankton extracts. Microplate sealing combined with ice cooling was proved an effective means for diminishing solvent evaporation during sample loading and minimized the analytical errors involved in Chl a measurements with a fluorescence microplate reader. A set of operating parameters (settling time, detector gain, sample volume) were also optimized to further improve the intensity and reproducibility of Chl a fluorescence signal. A quadratic regression model provided the best fit ( r = 0.9998) across the entire calibration range (0.05-240 pg μL). The method offered excellent intra- and interday precision (% RSD 2.2 to 11.2%) and accuracy (% relative error −3.8 to 13.8%), while it presented particularly low limits of detection (0.044 pg μL) and quantification (0.132 pg μL). The present assay was successfully applied on marine phytoplankton extracts, and the overall results were consistent (average % relative error −14.8%) with Chl a concentrations (including divinyl Chl a) measured by high-performance liquid chromatography (HPLC). More importantly, the microplate-based method allowed the analysis of 96 samples/standards within a few minutes, instead of hours or days, when using a traditional cuvette-based fluorometer or an HPLC system. [ABSTRACT FROM AUTHOR]

Heavy metal contamination in both sediments and molluscs from the Egyptian Mediterranean coast was investigated. Seawater, sediments, and mollusc samples were collected from representative locations along the coastal area. Different representations of the data set, including, statistical methods (correlation matrix and cluster analyses), various sediment quality assessment methods, and bioaccumulation factor calculation, were combined to investigate the trends of heavy metals, identify pollution sources, and assess sediment quality from a toxicological point of view. The measurements of dissolved oxygen (DO) revealed to relatively well oxygenate surface water in all locations. There is a distinct change in the contents of heavy metals (Fe, Al, Zn, Cu, Ni, Cr, Pb, Cd, and Hg) among the sampling sediments. The statistical interpretations showed that the bio-availability of the studied heavy metals is controlled by different factors, including the geo-chemistry of sediments, the hydrology of the system, the uptake of metals from sediments, as well as human anthropogenic activities. Although, there are still certain points of the Egyptian Mediterranean coast with a relatively high concentration of toxic metals, the toxicological approach suggests that the risk for living organisms is not high, but, in the long run, toxicological implications can appear. These results can provide useful information for the local managers and decision makers. [ABSTRACT FROM AUTHOR]

The aim of the present investigation was to quantify the levels of trace elements (Zn, Cu, As, Pb, Cd and total Hg) in the Mediterranean mussel, Mytilus galloprovincialis (L.). Based on their levels, the quality of Montenegro seawater for future mussel farming was estimated. The mussel M. galloprovincialis (L.) was collected from four sites in the Montenegrin costal area in the period of two years to determine trace element concentrations and to classify the quality of the coastal water and possible health risks from its consumption. The mean metal concentrations in the mussels ranged from 133.5-205.9 for Zn, 7.50-14.5 for Cu, 4.42-13.3 for As, 4.70-12.9 for Pb, 1.73-2.41 for Cd and 0.07-0.59 for total Hg in mg/kg dry weight. The levels of toxic metals (except for Pb) in the mussels were within the maximum residual levels prescribed by the laws of Montenegro, the EU and the USFDA. In addition, the trace metal concentrations found in the mussels in this study were similar to regional data using this mussel as a biomonitoring agent of seawater quality.

As copper-coated cadmium granules, which are recommended for use in the standard method for analyzing nitrate, are environmentally unfriendly and forbidden in some countries, an alternative method is required. To enhance the method for determining low nitrate concentration in seawater, the optimal conditions for reducing nitrate to nitrite using zinc powder were assessed in this study. The modified zinc method was optimal at an 0.8:1 (v/v) ratio of buffer solution (pH 8.5) (4 ml) to water sample (5 ml) with 50 mg of zinc powder and a standing time of 30 min. The nitrite was reacted with sulfanilamide and N-(1-Naphthyl)-ethylenediamine dihydrochloride after nitrate reduction, and spectrophotometrically quantified at 543 nm. This modified method was found to have a linear dynamic range of 0.1–7.0 μM, a low detection limit (0.1 μM), good intra-day and inter-day reproducibility (<5% relative standard deviation), high-efficiency reduction (>95%), and excellent accuracy in analysis of certified reference material (95% relative accuracy). The results obtained using the modified method agreed well with those obtained using the conventional cadmium column method. Overall, this alternative green chemistry method is a simplified procedure for determining nitrate in seawater with a high efficiency. • Zinc powder can be employed as reductant for determining nitrate in seawater. • The limit of detection of this modified method was as low as 0.1 μM. • The nitrate results obtained using this method agreed well with the standard method. [ABSTRACT FROM AUTHOR]