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Multidisciplinary researches allowed us to describe the morphological and palaeoenvironmental dynamics of the Kotychi Lagoon in the Holocene. This transition environment is separated from the open sea by a low barrier and has limited communication with it through a stable, short, and narrow inlet. The lagoon is limited by a modern alluvial plain made by several streams. Along the landward lagoon margins, small-scale deltas of these streams prograded into the lagoon. Intertidal and supratidal mud flats developed among the deltas, covered with vegetation (e.g., Salicornia sp.). Northwards, the lagoon is limited by a large marshy area. To the North of this area, a group of well-developed beach ridges parallel to the current shoreline is present. These are affected by erosion, and migrating sandy dunes have buried some of the beach ridges. South of the lagoon, the ancient Peneus River delta is located. The bottom depth in the Kotychi Lagoon decreases gradually from the landward of the barrier to the inner lagoon margins. Although the maximum depth is about 2.5 m in front of the inlet, the average depth is only 0.5 m. The main lithological type of the lagoon sediments is sandy mud, with some exceptions in the eastern edge of the lagoon and some locations around it where silty-clayey sediment was deposited. According to geomorphological surveys and palaeoecological interpretation of two cores analysis as well as with previous researches and datings, the recent morphogenetic evolution of this lagoon is mainly due to three Holocene phases: 1) 7-4 ka BP: sediment filling, development of a primitive open lagoon; 2) 4–1.5 ka BP: development of sandy ridges, partially closed lagoon; 3) 1.5 ka BP - present-day: closed lagoon, with one mouth. Fractal analysis confirms that currently the basin shape is evolving from a lagoon towards a coastal pond, due to contraction and filling up by sediments. [ABSTRACT FROM AUTHOR]

During a survey on the biodiversity of nematodes in the Petrel lagoon (central Chile), a population of Leptolaimus was found in sediment samples. Morphological, morphometric and molecular data indicated that the recovered nematode is a new species. This nematode belongs to the group in which the males only have four pre-cloacal tubular supplements present, and females have no supplements. The new species can be separated from the other species of the group by the length of both males and females (843-1060 μm), the tail length (118-208 μm), the shape of the gubernaculum, and the arrangement of the caudal setae in males (a pair of ventral precloacal setae at level of spicules, a pair of dorsal post-cloacal setae, two subventral and two subdorsal caudal pairs. The differences from closely related species L. gerlachi, L. praeclarus, L. octavus, L. hydrothermalis, L. vipriensis, and L. hadalis are discussed. The recovered population is described herein as Leptolaimus petrelense n. sp. [ABSTRACT FROM AUTHOR]

The Arab region is located in an arid environment and suffers from water scarcity and poor water quality which are expected to become more severe in coming years due to global warming. In this study, the groundwater quality of 205 wells in Qatar was investigated. The physical parameters of pH, electrical conductivity (EC), total dissolved solids (TDS), salinity, inorganic carbon (IC), and organic carbon (OC) were determined. The study characterized the concentrations of major anions of Cl, F, Br, NO3, PO4, and SO4, and major cations of Ca, K, Mg, and Na. Importantly, metals and metalloids including V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Ba, Pb, and U were determined. The results revealed that the groundwater of all wells is not drinkable due to high salinity (average TDS 4598 mg/L and salinity 0.4%, respectively). Additionally, average concentrations of major anions Cl, SO4, and F were 1472, 1064, and 1.9 mg/L, respectively, and all exceed the World Health Organization (WHO) guidelines for drinking water. However, NO3 concentration in 11 out of 205 wells was above the WHO guidelines of 50 mg/L due to intensive agriculture and fertilizer applications. Major cations of Ca, K, Mg, and Na were higher than WHO guidelines with average concentrations of 345, 63, 127, and 923 mg/L, respectively. All trace metals were much lower than the WHO guidelines for drinking water; however, the vanadium (V) average concentration in groundwater of all wells was 31 μg/L, which is five times higher than the Dutch guidelines (whereas the WHO has no guidelines for V). The groundwater of Qatar is dominated by Ca and Mg sulfates in Sabkha environments and dominated by NaCl in the coastal zones from evaporate environments consisting of coastal salt flats, salt pans, estuaries, and lagoons supersaturated by salts and the influence of sea water intrusion. [ABSTRACT FROM AUTHOR]

The Albufera of Valencia, a Mediterranean coastal lagoon, has experienced a shift to hypertrophic conditions over the past 40 years due to agricultural and urban-industrial pollution. From August 2023 to early 2024, the water of the lagoon turned reddish-brown. This change has been observed in the past, but never with this intensity or duration, which typically occurs during periods of drought. In this study, carotenoid concentrations were analyzed in relation to precipitation and temperature using field and remote sensing data from February 2016 to December 2023. In November 2023, samples showed unusually high concentrations of carotenoids. The study confirmed the effectiveness of a new algorithm for estimating carotenoids using Sentinel-2 imagery to complement chlorophyll-a data. Results showed that temperature and precipitation significantly influenced carotenoid/chlorophyll-a ratio, highlighting a climatic control of phytoplankton community structure. These results highlight the importance of long-term monitoring and conservation efforts to address climate change and human impacts. This research is a first step in using optical properties of lakes as an indicator of phytoplankton dynamics under environmental stress and warns of the potential for increased occurrence or persistence of such phenomena with future climate trends. [ABSTRACT FROM AUTHOR]

This article considers a newly developed model of Holocene shoreline displacement in the southern part of the former Ventspils Lagoon of the Baltic Sea basin (present-day western Latvia) in relation to data from previous and new archaeological research in the area, assessing the changing pattern of Stone Age settlement and resource utilisation during the Mesolithic and Neolithic. An extensive lagoon was formed at the time of the maximum level of the Ancylus Lake and once again during the Littorina Sea maximum. In the south of the lagoon, the former shores from the two separate phases of the lagoon's existence lie at similar elevations, providing the conditions for site re-occupation. There were river mouth sites on the continental shore of the lagoon and island sites on the seaward side, whereas in the periods with a low water level, human settlement focused on the relict waterbodies and watercourses within the exposed low-lying terrain of the former lagoon bed. The water-level fluctuations and resulting landscape changes were much more rapid during the Ancylus stage, the loci of settlement and resource exploitation necessarily shifting at fairly short intervals. The two lagoon phases also represent rather different aquatic environments. [ABSTRACT FROM AUTHOR]

This work analyzes the propagation properties of long-period ship-induced waves of vessels in confined waterways that are surrounded by wide and shallow water bodies using numerical simulations. Previous measurements indicated that, in the presence of shallow water surroundings, the drawdown being part of the long-period wave system can travel in the form of depression waves over several ship lengths distance [Parnell et al., "Ship-induced solitary Riemann waves of depression in Venice Lagoon," Phys. Lett. A 379, 555–559 (2015); Scarpa et al., "The effects of ship wakes in the Venice Lagoon and implications for the sustainability of shipping in coastal waters," Sci. Rep. 9, 19014 (2019)]. The exact conditions leading to these unexpectedly large propagation distances could to date not be clarified [Parnell et al., "Depression Waves Generated by Large Ships in the Venice Lagoon," J. Coastal Res. 75, 907–911 (2016)]. In this work, evidence from numerical simulations is presented, indicating that the far-field propagation properties are governed by the wave speed of the shallow water surroundings. In case the ship speed is larger than the surrounding wave speed (supercritical conditions), a free wave is continuously generated traveling over the shallow water with only minimal height decay. In the simulations, depression waves can travel over a distance of three ship-lengths with a height reduction below 10% in the supercritical regime, as compared to 80% height reduction in the sub-critical regime. In a one-dimensional environment, this agreement of free and forced wave speed is known as Proudman resonance. [ABSTRACT FROM AUTHOR]

Simple Summary: The Najeoer Pond, which is the object of this study, was created to be utilized as a test bed for the restoration of endangered species and for carrying out ecological education on the pond ecosystem. To achieve these goals, the Najeoer Pond was created for diversity and stability purposes by first securing various water depths imitating natural lagoons and inducing the establishment of various vegetation types according to the depth. As a result of analyzing the vegetation settlement process for 12 years after its creation through vegetation cover, species composition, species diversity, and the ratio of exotic species, and comparing the results with those of natural lagoons, the Najeoer Pond has been shaped to resemble the diversity and stability of natural lagoons. The carbon absorption capacity of the littoral vegetation established around the pond was significantly higher than that of forest vegetation. In this respect, the Najeoer Pond was also deemed to have a high creation effect in terms of ecological function. Therefore, a stable pond with diversity can be created because vegetation diversity can be guaranteed as a result of securing the ecological diversity of various water depths. The Najeoer Pond was created in a rice paddy as a part of a plan to build the National Institute of Ecology. To induce the establishment of various plants, the maximum depth of the pond was 2.0 m, and diverse depths were created with a gentle slope on the pond bed. When introducing vegetation, littoral and emergent vegetation were first introduced to stabilize the space secured for the creation of the pond, whereas the introduction of other vegetation was allowed to develop naturally. In this pond, floating, emergent, wetland, and littoral plants have been established to various degrees, reflecting the water depth and water table. As a result of stand ordination, based on vegetation data obtained from the created Najeoer Pond and a natural lagoon selected as the reference site, the species' composition resembled that of the reference site. Diversity, based on vegetation type, community, and species, tended to be higher than that of the reference site. The proportion of exotic species increased due to the disturbance that occurred during the pond creation process but continued to decrease as the vegetation introduced during the creation of the pond became established. Considering these results comprehensively, the restorative treatment served to increase both the biological integrity and ecological stability of the pond and, thus, achieved the creation goal from the viewpoint of the pond structure. [ABSTRACT FROM AUTHOR]

Intertidal groundwater springs provide thermally stable, nutrient‐rich freshwater that causes fine‐scale variability in water temperature and salinity and promotes biodiversity in coastal estuaries and lagoons. In this study, we combined three thermal sensing techniques to elucidate summer water temperature patterns at the mouths of intertidal groundwater springs and the ambient coastal lagoon in Prince Edward Island, Canada. Thermal infrared imagery captured the spatiotemporal variability in relative temperatures of the lagoon channel and cold‐water plumes from the springs. Thermal anomalies due to the springs were detected at the surface throughout a tidal cycle, suggesting that the thermal plumes were buoyant. Fiber‐optic distributed temperature sensing paired with temperature loggers near the spring outlets recorded groundwater temperatures at low tide (~ 7°C) but ambient lagoon temperatures (up to 26°C) at high tide due to the vertical thermal gradient in the stratified water column. Calculated estuarine Richardson numbers throughout the study confirm intertidal spring buoyancy due to salinity differences. The fiber‐optic distributed temperature sensing results revealed pronounced variations in temperature as evidenced by spatial (3.7°C) and temporal (5.5°C) standard deviations over the cable length during the study and lower mean lagoon bed water temperatures at high tide (22.5°C) than low tide (24.3°C) due to heat advection from tidal pumping. Lagoon temperatures fluctuate at diurnal (solar) and semi‐diurnal (tidal) frequencies. The findings emphasize the efficacy of a multi‐technology approach to reveal fine‐scale and dynamic thermal processes that drive temperature patterns and habitat distribution in coastal lagoon ecosystems and highlight the thermal influence of intertidal springs. [ABSTRACT FROM AUTHOR]

The article in the Journal of Fish Diseases discusses the prevalence and typology of skeletal abnormalities in fish from the Eastern Mediterranean. The study reports on various types of skeletal abnormalities found in specimens of 10 fish species from the Aegean Sea, with rates ranging from 3.3% to 28.6%. The research highlights the impact of anthropogenic pressures, pollution, and other factors on the occurrence of skeletal abnormalities in wild fish populations. The study emphasizes the need for further monitoring programs to understand the effects of fish abnormalities on natural stocks and mortality rates. [Extracted from the article]

This study assessed the impact of stressors on marine bivalves from three Moroccan lagoons – Moulay Bousselham, Sidi Moussa, and Oualidia – using biomarkers like Acetylcholinesterase, Glutathione-S-Transferase, Catalase, and Metallothioneins. Biomarker variations indicated pollutant impacts, including pesticides and heavy metals. Results showed distinct biochemical responses, with Oualidia lagoon indicating improved water quality and significant alterations in Sidi Moussa. Seasonal variations in Moulay Bousselham highlighted the importance of temporal dynamics in pollution assessment. This study emphasises the importance of multibiomarker approaches in assessing and preserving the health of Moroccan lagoons. [ABSTRACT FROM AUTHOR]

In this study, the current status of water quality in Güllük Lagoon and Köyceğiz-Dalyan Lagoon was examined by comparison using water quality indexes, multivariate statistical analyses and geographical information systems. Water quality parameters comprised of 9 variables i.e., WT, pH, DO, NO2-N, NO3-N, NH4-N, TP, SSM, BOD5 were measured in Güllük Lagoon and Köyceğiz-Dalyan Lagoon. Although there are important activities such as earthen pond fish farms, fish hatcheries, feldsbat and marble quarries, streams carrying domestic wastes, port, secondary residences and agricultural activities in Güllük Lagoon, there are intense tourism and agricultural activities in Köyceğiz-Dalyan Lagoon. The average concentrations of DO, TP, NO2-N results in Güllük Lagoon and DO, TP and NH4-N results in Köyceğiz-Dalyan Lagoon were determined in second class water quality according to surface water quality criteria. While both lagoons were found to be in "Good" quality class as a result of water quality index, Güllük Lagoon was found to be "medium polluted" and Köyceğiz-Dalyan Lagoon was found to be "slightly polluted" quality class as a result of comprehensive pollution index. It was observed that water quality index values of both lagoons decreased in the dry season, while their comprehensive pollution index values increased in the dry season. On the basis of the general averages of water quality index, it was found as Köyceğiz-Dalyan Lagoon (85.0) > Güllük Lagoon (84.05), and on the basis of the general averages of comprehensive pollution index, it was found as Güllük Lagoon (1.34) > Köyceğiz-Dalyan Lagoon (0.79). Relationships between variables were determined by geographical information systems (IDW technique) and statistical analyses (Descriptive statistics, Spearman rho correlation, Kruskal-Wallis test, multiple linear regression and Principal component analysis). As a result of multiple linear regression analysis in measured parameters, it was determined that the most important parameter affecting the water quality index in Güllük Lagoon was NH4-N, and the most important parameter affecting the comprehensive pollution index was SSM. In Köyceğiz-Dalyan Lagoon, it was observed that the water quality index was affected by the WT parameter and the comprehensive pollution index was affected by the SSM parameter. There is no difference in the concentrations of the average water quality parameters measured in both lagoons, and both lagoons are generally in the first and second class surface water quality class. However, Güllük Lagoon, which contains more different pollutant sources than Köyceğiz-Dalyan Lagoon, is shown to be more polluted according to water quality indexes. In addition, it has been determined that SSM is the most important parameter that determines the water quality among the measured water quality parameters of both lagoons. [ABSTRACT FROM AUTHOR]

Based on logging, core, thin section and geochemical analysis, the tectonic-lithofacies paleogeographic pattern of first member to third member of Ordovician Majiagou Formation (O1m1-O1m3 for short) in Ordos Basin is reconstructed, and the tectono-sedimentary evolution characteristics and oil-gas geological significance are discussed. The results are obtained in four aspects. First, a set of marginal argillaceous dolomites with high gamma ray value developed steadily and diachronously at the bottom of Majiagou Formation, which distributed over the Huaiyuan Movement unconformity, with d13C values positive drift characteristics comparable to global transgression of the Early Ordovician Floplian. Second, the global sea level rose and the ancient land was submerged into the underwater uplift in O1m1 to O1m2, and the central uplift was deposited for the first time in the Ordovician, forming a tectonic pattern of "one uplift and two depressions". Subsequently, the subduction and extrusion outside the basin and the differentiation of uplift and depression in the basin of O1m3 resulted in the activation of the Wushenqi-Jingbian bulge. Third, the evolution of the tectonic pattern had a significant impact on the sedimentary paleoenvironment. The O1m1 overlaps westward, and saline lagoon is formed in eastern depression and influenced by the transgression. The transgression continued in O1m2 and resulted in communication with the wide sea, and the large-scale grain shoal developed around eastern depression, and the late dry shrinkage formed a small scale evaporite lagoon in upper part. Under the influence of highland sealing in O1m3, the water body gradually differentiated into dolomitic gypsum and saline lagoons to the east, and the grain shoal spread along the highs around sag. Fourth, the source rocks developed diachronously at the bottom of Majiagou Formation form a favorable source-reservoir assemblage with the shoal facies reservoir distributed around the slope of O1m2-O1m3, and they have certain exploration potential for natural gas. [ABSTRACT FROM AUTHOR]

In Unare and Píritu Coastal Lagoons, a study was carried out to assess the effect of C, N, and P load contributions on the capability of the sediments to immobilize phosphates. To achieve the later, the geochemical data of the sediments were coupled to the P‐sorption index of Bache and Williams (IBW). In both lagoons, the sediments showed a pH > 7 because of calcareous sedimentation. The inorganic carbon values in the lagoons displayed a spatial distribution with higher concentrations toward the shores, that is defined by the carbonate lithology. On the contrary, the inner part of the lagoons was characterized by the presence of organic materials associated to the clay. The phosphorus content in the Unare Lagoon ranged from 290 to 625 mg kg−1, whereas in the Píritu Lagoon the values fluctuated between 213 and 1013 mg kg−1. The highest concentrations of phosphorus in both lagoons could be linked to sewage and runoff input from agricultural and livestock activities around the lagoon systems. The IBW displayed adsorption average values of 21.97 and 27.42 for Unare and Píritu Lagoon, respectively, corresponding to a rather low P sorption. In Unare Lagoon, the IBW showed positive correlations with C, N and Felabile but negative with P. However, in the Píritu Lagoon, despite the analogous lithology of the lagoons, a slightly positive non‐significative correlation between IBW and IC was only found. Although the sediments adsorb P with a rather low capacity, they can mitigate the eutrophication process in the studied lagoons. [ABSTRACT FROM AUTHOR]

It is increasingly recognised that nature‐based solutions in coastal ecosystems provide significant services compared to hard engineering measures. Several restoration projects are now being conducted worldwide to protect coastlines against flood risk and improve the ecosystems' quality. In the case of river deltas, managed realignment through levee breaching is becoming a recognised strategy for coastal wetland restoration. This study focusses on the formation of new wetlands in the Po River Delta after several natural dyke failures that occurred during the last century, when a large part of the land was abandoned and became wetlands. An historical review was performed to quantify the variation of the marsh extent in time developed after natural levee breaching in the easternmost lagoons of the delta and to understand the processes that determined their evolution. The analyses were based on orthophotos from the 1950s to the present‐day integrated with tidal records, water and sediment discharge records, and GPS survey for vegetation distribution. The review indicated that, between the 1950s and 1980s, anthropisation and natural processes caused a strong decline in marsh extent, thus leading to the recent shape of the lagoons. Several breaches and inlets were developed because of a combination of human intervention and erosive processes, and new tidal systems were born. Three main depositional areas connecting the main river branches were identified in three separated lagoons of the delta. These lagoons presented a 'crevasse splay' type of deposition which allowed the development of new tidal flats and, in certain cases, of large freshwater marsh systems within less than 8 years after the breach. The newly formed wetland systems (>100 ha) demonstrate the ability of the Po River Delta to build new wetlands, also during periods of human‐induced sediment starvation and high rates of subsidence, suggesting that further levee breaching should be exploited to favour marsh recovery. [ABSTRACT FROM AUTHOR]

Cryptofauna are an overlooked faunal group due to their hidden nature and the use of conventional survey methods, despite playing a significant role in the ecosystem complex as keystone taxa. In this study, a structural framework, viz. cryptofauna monitoring structure (CMS) was developed to assess cryptofauna living in the lagoon reef environment and their preference to various substrates. The efficiency of CMS modules was tested by deploying them in coral lagoons in Agatti and Kavaratti of the Lakshadweep Archipelago, India. A total of 24 CMS units, sets of four, were deployed in these islands at live coral, dead coral and sandy habitat sites. Retrieval of CMS units revealed a total of 424 individuals of motile and sessile organisms representing 12 different taxonomic groups collected. Among the habitats, the sandy area had a high taxa number while the dead coral area had a high taxa abundance. Polychaetes and gastropods were the dominant faunal groups regardless of habitat and island. The present study suggests that CMS can be an efficient tool to assess cryptofauna diversity, which could make monitoring cryptobionts more affordable and environment-friendly. In addition, this study lays the foundation for research into cryptic reef benthos in India. [ABSTRACT FROM AUTHOR]

The article explores the relationship between water quality and vulnerabilities faced by small-scale fishery communities in Chilika Lagoon, India. It discusses the impact of invasive shrimp aquaculture activities and hydrological interventions on water quality and fish populations, as well as the social and economic vulnerabilities in the small-scale fisheries system. The study aims to bridge the gap in understanding the role of water quality in vulnerability analysis and provides insights into coping responses and adaptive capacity for sustainable small-scale fisheries. The Chilika Lagoon has faced challenges such as pollution, biodiversity loss, and employment insecurity, leading to ecological, social, economic, institutional, and technological vulnerabilities for fishing communities. The text also discusses coping and adaptation strategies employed by these communities, the use of mobile phones and ICT tools in fisheries, and the importance of protecting water quality and implementing adaptation measures. The given document is a list of references and citations from various sources related to climate change, social vulnerability, and fishing communities in the Chilika Lagoon in India. These sources provide valuable information for researchers interested in understanding the impacts of climate change on fishing-dependent communities and the measures taken to address these challenges. The given text is a list of references and citations from various sources related to the topic of small-scale fisheries in the Chilika Lagoon in India. These sources cover a range of topics including social-ecological regime shifts, water quality, biodiversity, climate change, and the impact of human activities on the lagoon. They provide valuable information for [Extracted from the article]

This study investigates the biomass production and growth strategies of the relict seagrass Zostera marina, a species sensitive to high temperatures, within the Venice Lagoon (Italy). Monthly data collected from January to December 2019 and November 2020 to October 2021 in a single station in proximity of one lagoon port-entrance, along with seasonal data from 2018 and 2021 for the whole lagoon, were analyzed in conjunction with environmental parameters and macroalgal presence. The objective was to understand the impact of climate changes, particularly rising water temperatures, on the cover, standing crop and net primary production of Z. marina and the effect of the MoSE gate closures designed to protect Venice from high-water events. Despite expectations of a decline due to temperature increase and reduced water exchange, our findings reveal a notable adaptability of Z. marina, with increases in both cover and biomass. This resilience suggests that Z. marina can counteract environmental challenges, making this study relevant for broader ecological and conservation contexts beyond the Venice Lagoon. [ABSTRACT FROM AUTHOR]

Coastal lagoons are important wetland sites for migratory species and the local flora and fauna population. The Stagnone Lagoon is a coastal lagoon located on the west edge of Sicily between the towns of Marsala and Trapani. The area is characterized by salt-harvesting plants and several archaeological sites and is affected by microtidal excursion. Two mouths allow exchange with the open sea: one smaller and shallower in the north and one larger and deeper in the south. This study aims to understand the lagoon's hydrodynamics, in terms of circulation and involved forces. The circulation process appears to be dominated mainly by tide excursions and wind forces. Wind velocity, water levels, and water velocity were recorded during different field campaigns in order to obtain a benchmark value. The hydrodynamic circulation has been studied with a 2DH (two-dimensional in the horizontal plane) unstructured mesh model, calibrated with data collected during the 2006 field campaign and validated with the data of the 2007 campaign. Rapid changes in averaged velocity have been found both in Vx and Vy components, showing the strong dependence on seiches. This study tries to identify the main factor that domains the evolution of the water circulation. Sensitivity analyses were conducted to estimate the correct energy transfer between the forcing factors and dissipating ones. A Gauckler–Strickler roughness coefficient between 20 and 25 m1/3/s is found to be the most representative in the lagoon. To enhance the knowledge of this peculiar lagoon, the MIKE 21 model has been used, reproducing all the external factors involved in the circulation process. Nash–Sutcliffe coefficient of efficiency (NSE) values up to 0.92 and 0.79 are reached with a Gauckler–Strickler coefficient equal to 20 m1/3/s related to water depth and the Vy velocity component. The Vx velocity component NSE has never been satisfying, showing the limits of the 2D approach in reproducing the currents induced by local morphological peculiarities. Comparing the NSE value of water depth, there is a loss of up to 70% in model predictivity capability between the southern and the northern lagoon areas. This study aims to support the local decision-makers to improve the management of the lagoon itself. [ABSTRACT FROM AUTHOR]

The mangrove oyster Saccostrea palmula is a relatively small but emerging species in aquaculture, and it is necessary to resume and increase studies on its cultivation. Therefore, we carried out a study that includes three main components for developing S. palmula culture in the Mexican Central Pacific: spat collection, pre-growth phase (eight weeks), and grow-out phase (six months). We tested natural (shell strings) and artificial (coupelles) collectors placed in contrasting environmental conditions: marine (La Boquita) and estuarine (Cuyutlan). The spat was pre-grown in suspended Australian trays at the two collection sites and under in-land pond conditions. Then, it was pooled under an estuarine environment and in a single lot for the final culture phase in Juluapan lagoon (all sites in Colima, Mexico). Spat collection was higher in coupelles (858.3 ± 175.6 spat coupelle-1) than in shell strings. The number of spat collected (13,062 spat), final pre-growth size (26.5 ± 0.6 mm shell height), and pre-growth survival (94.7%) were higher in La Boquita (marine environment). The final culture phase in Juluapan (estuarine conditions) was successful, recording an average height of 54.2 ± 4.9 mm and average total weight of 30.8 ± 6.9 g after six months of culture, after spat collection and pre-growth periods. We found the largest oyster, S. palmula, ever recorded (shell height 83.3 mm and total weight 59.4 g), and we confirmed that S. palmula has potential for artisanal aquaculture and socioeconomic regional development in the Mexican Central Pacific. [ABSTRACT FROM AUTHOR]

This study aims to (a) determine the concentration and distribution of elements in the surface sediments of the Erikli Lagoon, which are under natural and anthropogenic pressure, (b) determine possible effects on the environment using ecological indices, and (c) reveal possible sources. Multiple elements, total organic carbon and chlorophyll degradation products were analyzed in sediment samples. Enrichment factor (EF), contamination factor (CF), and geoaccumulation index (Igeo) were calculated to determine the sources of the elements. Modified hazard quotient (mHQ), ecological contamination index (ECI), contamination severity index (CSI) and potential ecological risk index (PERI) were calculated to determine ecological risks. It was found that Mn, Hg, As, Fe and Cd entering the lake are of anthropogenic origin. These elements pose a low to moderate ecological threat to the lake. Agricultural and domestic discharges and atmospheric deposition are the main sources of these elements. A moderate ecological risk with an average value of 194.89 was determined in the lagoon based on PERI and contamination levels of metals. The elements that pose this risk are Hg and Cd, due to their high toxicity. According to ECI and CSI, the ecological risk is low, with average values of 0.99 and 0.30, respectively. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive assessment of the black-barred halfbeak (Hemiramphus far) in Bardawil Lagoon, North Sinai, Egypt, focusing on key parameters such as length at first capture, growth metrics, mortality rates, and relative yield per recruit. Data were collected monthly from May to December 2022, comprising a total of 1,593 fish samples from commercial catches in the lagoon. The fish that were sampled ranged in length and weight from 17 to 36.7cm and 22 to 247.3g, respectively, with an average of 23.84cm and 85.67g. The formula for the length-weight relationship of the studied species was W = 0.0029 TL 3.2286. This study showed four age groups. The estimated von Bertalanffy growth parameters were L∞ = 37.8cm and k = 0.48 year-1. It was found that the growth performance index (Φ ') was 2.84. An estimate of the length at first capture was 20.89cm. The length at first capture was determined to be 20.89cm. The mortality rates were calculated as follows: total mortality (Z) at 2.15, natural mortality (M) at 0.95, and fishing mortality (F) at 1.2 year-1. The exploitation rate (E) was found to be 0.56, indicating overfishing and high fishing pressure on the population. The relative yield per recruit analysis (Y'/R) showed that the current exploitation level significantly exceeds the sustainable threshold (E0.5=0.383). To sustainably manage this resource, the current exploitation rate needs to be reduced by 32%, decreasing from 0.56 to 0.383. The findings from this investigation are critical for the assessment and management of the H. far fishery in Bardawil Lagoon, ensuring the sustainability of this important fish species. [ABSTRACT FROM AUTHOR]

Burullus, a highly enclosed wetland at the mouth of the River Nile, receives biogenic elements primarily from the Nile River and serves as an ideal area for studying how changes in the watershed, particularly since the construction of the Aswan Dam, have impacted the estuarine lakes' environment. This study aimed to reveal the differences in nutrient salt levels in the estuarine lakes before and after the Aswan Dam's construction, as well as addressing the effects of these changes on the ecological environment through 210Pb dating of Burullus Lagoon B1 cores, combined with testing and analyzing the total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), and biogenic silica (BSi), alongside the historical data. The results showed that sedimentary TOC, TN, and TP contents generally increased from bottom to top. This indicates that despite the significant reduction in nutrient fluxes due to the Aswan Dam, nitrogen (N) and phosphorus (P) concentrations in downstream lakes did not decrease owing to the substantial increase in N and P inputs from human discharges downstream, and that sedimentary TN/TP ratios were all below 16, suggesting that the lakes remained phosphorus-limited. While, the biogenic silica (BSi) and the BSi/TOC ratio both showed a decreasing trend from bottom to top, indicating that the reduction of water and sediment caused by the Aswan Dam has led to a decline in diatom biomass and their overall contribution to primary productivity in the wetland, suggesting that the ecological environment may deteriorate over time. [ABSTRACT FROM AUTHOR]

Mediterranean lagoons face a significant threat due to the prevalent risks of eutrophication and dystrophy, particularly in sectors with limited water renewal. The El Mellah Lagoon in northeastern Algeria represents a crucial ecosystem. Our study focused on assessing its operational state by examining the seasonal variability of spatial patterns indicative of eutrophication. Our primary hypothesis posited that a lack of fluctuation in spatial pattern expression reflects ecosystem dysfunction in the face of eutrophication-related disturbances. Our objective was to establish that the El Mellah Lagoon maintains robust health, capable of recovering or sustaining dynamic equilibrium following periods of instability induced by external or internal disruptions. To achieve this, we employed a methodology combining multidimensional analysis (utilizing STATIS from the K-TABLE family) and spatial analysis (employing Moran's I and ordinary Kriging interpolation). Statistical analyses of physicochemical and biological measurements revealed seasonal variations in key eutrophication parameters. The first principal components derived from the STATIS analysis underwent spatial analysis techniques. Consequently, the spatial models constructed unveiled the dynamics characterizing the operational states of the El Mellah Lagoon. This comprehensive approach aimed to demonstrate the lagoon's resilience and ability to withstand disturbances, fostering a dynamic equilibrium crucial for its long-term viability. [ABSTRACT FROM AUTHOR]

The Tam Giang-Cau Hai lagoon (TGCH) in Thua Thien Hue province (Vietnam) is a marsh/lagoon system and ranks among the largest waterbodies in Southeast Asia. It plays a significant role in terms of both socio-economic and environmental resources. However, anthropogenic stress, as well as the discharge of untreated domestic and industrial sewage with agricultural runoff from its three major tributaries, dramatically damages the water quality of the lagoon. Especially after heavy rain and flash floods, the continuous degradation of its water quality, followed by harmful algal and cyanobacterial bloom patterns (HABs), is more perceptible. In this study, several physicochemical factors, cyanotoxins (anatoxins (ATXs), saxitoxins (STXs), microcystins (MCs)), phycotoxins (STXs, okadaic acid (OA), and dinophysistoxins (DTXs)) were analyzed in water and shellfish samples from 13 stations in June 2023 from 13 stations, using enzyme-linked immunosorbent assay (ELISA) kits for the ATXs and STXs, and the serine/threonine phosphatase type 2A (PP2A) inhibition assay kit for the MCs, OA, and DTXs. The results showed for the first time the co-occurrence of freshwater cyanotoxins and marine phycotoxins in water and shellfish samples in this lagoon. Traces of ATXs and STXs were detected in the shellfish and the orders of magnitude were below the seafood safety action levels. However, toxins inhibiting the PP2A enzyme, such as MCs and nodularin (NODs), as well as OA and DTXs, were detected at higher concentrations (maximum: 130.4 μg equiv. MC-LR/kg shellfish meat wet weight), approaching the actionable level proposed for this class of toxin in shellfish (160 μg of OA equivalent per kg of edible bivalve mollusk meat). It is very important to note that due to the possible false positives produced by the ELISA test in complex matrices such as a crude shellfish extract, this preliminary and pilot research will be repeated with a more sophisticated method, such as liquid chromatography coupled with mass spectroscopy (LC-MS), in the upcoming research plan. [ABSTRACT FROM AUTHOR]

This study evaluated the ingestion of microplastics (MP) by copepods in Terminos Lagoon (TL), a RAMSAR-listed site in the southern Gulf of Mexico. The evaluation was carried out in two contrasting seasons of 2022, as follows: the dry (April) and the rainy (October). Copepods were collected using a conical plankton net (mesh size of 200 μm). In the laboratory, a pool of all pelagic adult copepod taxa was picked, and the MP inside the organisms were extracted, classified, and photographed using traditional optical and scanning electron microscopy. A total of 268 MP particles were extracted from the interior of copepods; among them, 149 and 119 corresponded to the dry and rainy seasons, respectively. The ingestion rate in the dry season was 0.14, while in the rainy season, it was 0.11. In addition, fibers, plastic fragments, and microspheres with different colors (blue, red, black, green, transparent, and multicolored), sizes, forms (angular, round, triangular, and twisted), and textures were also detected. Fibers were the most abundant MP found in a proportion of more than 85%. In addition, in some sampling sites, microspheres were observed with high relative abundance values (80%). In some sites, fragments reach 20% of the total abundance. Significant differences were observed between the two seasons. The sites closest to the urban area adjacent to TL observed high diversity and abundance of MP. The higher abundance of MP in the dry season is due to lower river discharge, on the other hand. Thus, MP particles accumulate and become available for consumption by copepods. This is the first study that has revealed that the MP was ingested by the copepods in TL. Furthermore, this study provides a baseline information for future research on the abundance of MP in the Gulf of Mexico region. [ABSTRACT FROM AUTHOR]

We present descriptions of two newly discovered species of Myxobolus (Myxobolidae) that infect Mugil curema: Myxobolus mundauensis n. sp. found in gills and Myxobolus patriciae n. sp. found in intestines. These descriptions are based on the morphology of myxospores, histological analysis, and sequencing of the small subunit ribosomal DNA (ssrDNA). The myxospores of both species differ in the width and length of their spore bodies, and their ssrDNA sequences showed a 10.6% difference. These findings support the identification of these parasites as distinct and previously unknown species. Phylogenetic analysis revealed a subclade consisting of species that parasitize Mugiliformes, with Myxobolus mundauensis n. sp. being closely related to Myxobolus maceioensis, and Myxobolus patriciae n. sp. being closely related to Myxobolus curemae. Our analysis aligns with previous research suggesting a strong correlation between host orders and phylogenetic patterns within the Myxobolidae family. [ABSTRACT FROM AUTHOR]

Non-indigenous species (NIS) introduction notoriously threatens the Mediterranean Sea. In addition, Mediterranean coastal lagoons play a crucial role as nurseries for marine species, which new NIS arrivals can threaten. Therefore, monitoring and early warning of NIS presence is essential in preserving biodiversity. An innovative technique for rapid and accurate species identification and biodiversity screening is the application of environmental DNA (eDNA) metabarcoding. In this research, different Penaeidae (Arthropoda, Crustacea, Decapoda) NIS specimens were collected from a Mediterranean coastal lagoon after an early warning about a potentially invasive NIS arising from next-generation sequencing data. DNA barcoding of the DNA extracted from tissue samples and amplified with specifically designed primer pairs led to the recognition of Penaeus aztecus in this NATURA 2000 protected ecosystem for the first time. DNA barcoding from DNA isolated from the water where the living specimens were stored further validated the possibility of identifying P. aztecus starting from eDNA. This approach demonstrated the validity of environmental DNA analysis in the early screening of potentially invasive NIS presence in Mediterranean protected areas and ecosystems. This work describes an applicative example of the efficacy in improving the biomonitoring of lagoon ecosystems using molecular tools and it represents a guideline for the validation of eDNA metabarcoding data for the presence of potentially invasive species. [ABSTRACT FROM AUTHOR]

Most Andean lakes and lagoons are used as reservoirs to manage hydropower generation and cropland irrigation, which, in turn, alters river flow patterns through processes of storage and discharge. The Carhuacocha and Vichecocha lagoons, fed by glaciers, are important aquatic ecosystems regulated by dams. These dams increase the flow of the Mantaro River during the dry season, supporting both energy production and irrigation for croplands. Water quality in the Carhuacocha and Vichecocha lagoons was assessed between storage and discharge events by using the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) and multivariate statistical methods. The quality of both lagoons is excellent during the storage period; however, it decreases when they are discharged during the dry season. The most sensitive parameters are pH, dissolved oxygen (DO), and biochemical oxygen demand (BOD). This paper details the changes in water quality in the Carhuacocha and Vichecocha lagoons during storage and discharge events. [ABSTRACT FROM AUTHOR]

Acid tars, a waste unique to the oil processing industry, pose a significant toxicity risk. These by-products originate from refining certain petroleum fractions, such as oil and paraffin, and are commonly found in the waste streams of crude oil processing. In Romania, particularly in the post-war period, acid tars were predominantly managed through storage. Although advancements in catalytic processes have considerably reduced the generation of acid tars in the Romanian refining industry, an efficient treatment method is still required to address the existing acid tars lagoons. The present research refers to a case study carried out on a laboratory scale for the physico-chemical stabilization/encapsulation of acid tars from a lagoon belonging to a refinery in Prahova-Romania county. The experimental program aimed at formulating and applying optimal stabilization recipes for acid tar from the selected lagoon was conducted to reduce the total hydrocarbon and toxic metal content, in compliance with Order No. 95 of 12.02.2005 from Romanian legislation. The leaching data showed that the recipes that stabilize and encapsulate acid tar provide a good immobilization capacity for the five heavy metals (Pb, Cd, Cu, total Cr, Ni) and As, while their releases are dependent on the pH- and varies with the total hydrocarbon content of the treated tar. The laboratory study carried out and presented in this work, as well as the results obtained after performing the leaching test, allow the extrapolation and application of this stabilization - encapsulation procedure on a macro-in situ scale and the remediation of the lagoon where the acid tar was stored. [ABSTRACT FROM AUTHOR]

According to European Union guidelines, the assessment of the ecological status of Transitional Water Systems (TWSs) should be based on the monitoring of biological communities rather than physico-chemical parameters and pollutants. Macrophytes, including aquatic angiosperms and macroalgae, are organisms that respond more quickly to environmental changes by varying the structure and biomass of their assemblages. There are several ecological indices based on macrophytes, among them the Macrophyte Quality Index (MaQI), which has been intercalibrated with water and sediment parameters, nutrient concentrations, and pollutants and is used to determine the ecological status of Italian TWSs. In the Venice Lagoon, it was applied to 87 stations, showing a significant score increase over the last ten years of monitoring (2011–2021) due to progressive lagoon environmental recovery. The dominant taxa assemblages, previously dominated by Ulvaceae, were replaced by species of higher ecological value, with an increase in the number and distribution of sensitive species, as well as the spread and cover of aquatic angiosperms. The rise in the Ecological Quality Ratio (EQR) determined by the MaQI confirms the key role of macrophyte monitoring in detecting environmental changes in TWSs. In fact, a simple check of the presence or absence of aquatic angiosperms and sensitive species is sufficient for an initial rapid assessment of the ecological status of these environments. [ABSTRACT FROM AUTHOR]

This study investigates the effects of tidal cycles on the zooplankton community within the Cotonou Channel, an important waterway connecting the large Nokoué Lagoon to the Atlantic Ocean in Benin. From the determination of zooplankton composition from 25-hour samples collected in July 2020, alpha diversity indices and abundance were assessed, while relationships between biotic and abiotic parameters were analyzed through Pearson correlation, analysis of variance, and principal component analysis. A total of 66 zooplankton taxa were identified, with rotifers exhibiting the highest species richness (35 taxa), while copepods dominated in abundance (71%). Zooplankton abundance varied significantly, ranging from 2 to 95 ind L−1 depending on the tidal phase. A negative correlation was found between species richness (r = −0.51, p < 0.01) and increasing salinity (3–37), indicating that higher salinity reduced diversity (r = 0.06, p > 0.05). Resilient species like Synchaeta bicornis persisted despite salinity changes. The tidal cycle structurally altered the zooplankton community, with abundance and diversity peaking at different phases, notably higher at high tide (15 ind L−1.) These initial findings underscore the complex interactions between tidal dynamics and estuarine biodiversity, suggesting the need for further research across different tidal and seasonal conditions to inform effective management and conservation efforts. [ABSTRACT FROM AUTHOR]

Using gamma and alpha spectrometers, the radioactive isotopes 226Ra, 210Pb, 232Th, and 40K were determined in three sediment cores from the Tam Giang-Cau Hai (TG), Thi Nai (TN), and Nai (DN) lagoons, and radiation risk indices were computed. The radioactivity concentrations of 210Pb, 40K, 232Th, and 226Ra were 55.46 Bq/kg, 675.78 Bq/kg, 67.22 Bq/kg, and 34.15 Bq/kg, respectively. The Raeq, ADR, AEDE, Iγr, AUI, Hex, and AGDE indices were 182.31 Bq/kg, 84.46 nGy/h, 0.10 mSV/y, 1.35, 1, 18, 0.49, and 598.71 µSV/y, respectively; the values of 40K, 232Th, AEDE, ADR, Iγr, and AGDE were greater than the global average and UNSCEAR values. The radioactivity and radiation risk indices decreased in the order DN > TN > TG. [ABSTRACT FROM AUTHOR]

Governments play crucial roles in addressing social-ecological traps – situations where feedbacks between social and ecological systems lead to reinforcement between resource degradation and livelihood impoverishment. While it is widely recognized that resolving these traps necesitates integrated measures, empirical studies often focus on the impact of individual measures. This paper investigates all measures employed by the local government to address traps in small-scale fisheries and aquaculture and examines how these measures contribute to solving the traps. Based on empirical data from the Tam Giang lagoon, Central Viet Nam, it finds that the goverment develops measures that align with "good practices" which focus on both ecological and social challenges. Yet, in practice, it prioritizes addressing ecological challenges over the social ones. The government primarily directs resources and efforts toward combating resource degradation. Measures that tackle the high dependency on fisheries resources and lack of alternative livelihoods are often sidelined. These practices fail to address the key drivers and reinforceing feedbacks that create the social-ecological trap. The paper highlights gaps between science, policy and practice in addressing social-ecological traps. Bridging these gaps and transforming government responses to the traps require effective communication of scientific knowledge to the government; facilitation of collaborations among researchers, policymakers, managers and practictioners; provision of financial support to the goverment and addressing the lack of political will of the government. [ABSTRACT FROM AUTHOR]

Enhalus acoroides (L.f.) Royle is a large and important foundation seagrass species in the tropical Indo-Pacific. The northern marginal populations in China have been declining over the last decades. The reproductive phenology and fruit set of this dioecious seagrass were investigated from June 2017 to February 2018 in two areas in Li'an lagoon, Hainan Island, China. We found that E. acoroides flowered year-round. However, the flowering intensity varied among seasons and was highest in the summer and lowest in the winter. The shoot sex ratio was male-biased, and the pollen-ovule ratio was approximately 104: 1, based on the sex ratio and the number of male florets per inflorescence. Female and male plants flowered at the same time in this population. Despite the high reproductive investment in terms of flower formation observed throughout the year, the abundance of the mature fruits was low, possibly due to physical disturbance and cover by epiphyte and algae. This study provides insight into the reproductive ecology of E. acoroides, which will be useful for the future conservation of this threatened seagrass. [ABSTRACT FROM AUTHOR]

Metagenomics is an important technique for discovering and screening significant bioactive compounds such as polyketide synthases, non-ribosomal peptide synthetases, antibiotics, and biocatalysts. The enormous potential of microbial diversity in coastal lagoons remains untapped because of the difficulty of culturing many microorganisms under laboratory conditions. Therefore, this study aimed to decipher the structural and functional diversity of microbial communities, including un-culturable species in lagoon sediments collected from Tam Giang, Nai, and Thi Nai lagoons, which were located in the central coast of Vietnam using metagenomics approach. The results showed that all three large lagoons exhibited a high diversity of fungal species among the eukaryotic species and a high diversity of bacterial and archaeal species. Among them, the most prominent phyla included Ascomycota (fungal phyla), Firmicutes and Proteobacteria (bacterial phyla), and Thaumarchaeota (archaeal phyla). Sequencing of the metagenome samples of microbiome in the three lagoons of Tam Giang, Nai, and Thi Nai using shotgun sequencing technology revealed the existence of 126 potential gene sequences from the Tam Giang lagoon, 346 sequences from the Nai lagoon, and 341 sequences from the Thi Nai lagoon. These sequences participated in various metabolic processes and belonged to more than 30 groups of biologically active compounds. Most of these genes were related to antibacterial, antifungal, antiviral, cancer cell inhibition, and antioxidant activities. This is the first study conducted on lagoon microorganisms in Vietnam, opening up prospects and potential in exploiting microorganisms and biologically active substances with important applications in life from the lagoon ecosystems of Vietnam in particular and the overall world in general.

Rationale: Carbon (δ13C) and nitrogen (δ15N) stable isotope analysis is a powerful tool to investigate diverse questions in fish ecology, such as their trophic position or migration strategies. These questions appear particularly important to protect endangered European eel. However, elevated lipid content in eel muscle can bias δ13C values, as lipids are 13C‐depleted compared to proteins and carbohydrates. Methods: We measured δ13C and δ15N values of bulk and lipid‐free samples of eel muscle. Lipid‐free samples were obtained after the extraction of lipids with cyclohexane. Lipid‐corrected δ13C values, using five different mathematical equations based on bulk δ13C values, were compared to lipid‐free δ13C values. We also evaluated the effect of lipid extraction on δ15N values. The analyses were based on linear regression performed on 333 individuals captured in nine lagoons and four rivers. Results: Independently to the capture site or habitat (river or lagoon), the predicted lipid‐corrected δ13C values were highly consistent with the measured lipid‐free δ13C values (R2 > 0.90). The application of specific equations for each habitat or capture site only slightly increases these R2 (1.5% or less). The lipid extraction treatment significantly decreased by 0.2‰ the δ15N values compared to bulk samples. Conclusions: Given the excellent prediction of mathematical equations and the small decrease of δ15N values after lipids extraction, we propose to use mathematical correction to estimate δ13C values of eel muscle. As the habitats or sites did not strongly influence the results, the coefficients from our study can be applied to other studies on European eel. [ABSTRACT FROM AUTHOR]

The coastlines of the southwestern Pacific are dynamic environments that have been repeatedly reshaped by tectonic forces as well as changing global climate and sea level. It has been theorized that much of the north coast of New Guinea was sparsely inhabited until stabilization of coastal flats fallowing the Mid-Holocene Thermal Maximum and resulting marine high stand. We report on environmental proxy indicators measured in core samples taken near modern day Aitape, Papua New Guinea. These cores record the formation of a large lagoonal system on the modern coastal flats by 5800 cal BP. This lagoon infilled over the next several 1000 years as sea level dropped, with the modern coastal flats stabilizing by 1400 cal BP. A charcoal record spanning the period between 6200 and 1400 cal BP documents substantial increases in influx between ~6200 and 6000 cal BP and particularly from ~3000 to 2600 cal BP. Comparison to regional charcoal and ENSO records suggests that increasing aridity and ENSO intensity may drive regional patterning in fire records, however, localized charcoal records are also heavily influenced by human activity. Between 3000 and 2600 cal BP, forest management practices in the Aitape area, currently focused on tree crops and horticulture characterized by long fallowing and limited burning, shifted to a regime characterized by large scale forest clearance and shorter fallowing. We hypothesize that increasing population driven by abundant Mid-Holocene lagoonal resources may have been difficult to maintain as lagoons infilled and climate became more variable, leading to horticultural intensification. [ABSTRACT FROM AUTHOR]

Intermittently open and closed lakes and lagoons (ICOLLs) are globally important estuarine systems that are separated from the ocean by a sand beach barrier or berm. The barrier may open or close naturally because of sand and sediment movement or be manually opened by estuarine managers in times of flooding. As intermittently closed systems, it is important to understand the potential for eutrophication and what are the best indicators. This study investigated water quality, sediment quality and benthic processes in four shallow ICOLLs in Sydney, Australia, that experience a range of nutrient loadings. Manly and Curl Curl Lagoons experience higher turbidity and concentrations of pelagic Chl-a compared to Dee Why and Narrabeen Lagoons. They also differ with respect to general morphology with Manly and Narrabeen deeper and more linear while Curl Curl and Dee Why are shallower and more circular. Relationships between nutrient loading and traditional water quality indicators of eutrophication such as chlorophyll-a, turbidity and dissolved oxygen appeared to be moderated by lagoon morphology and hydrology, which control the ratio of pelagic to benthic production and net accumulation of sediment organic matter. We found that all the lagoons investigated were net heterotrophic, with Narrabeen and Manly the least and the most heterotrophic respectively. Ratios of total organic carbon (TOC):benthic community respiration (CR) varied among lagoons and were likely related to the dominance of refractory organic matter in Narrabeen (~ 99%), and more labile organic matter in Manly and Curl Curl Lagoons (~ 90%). Benthic community respiration increased with nutrient loading rates across the lagoons, suggesting that benthic processes are a critical indicator of eutrophication in these shallow systems. In contrast to the generalised conceptual model of eutrophication in coastal systems whereby nutrient pollution causes a reduction in benthic primary productivity at the expense of increased pelagic primary productivity, our results suggest that benthic microalgal productivity in shallow ICOLLs plays an important role in buffering against eutrophication of the water column but may also contribute to organic enrichment of sediments. [ABSTRACT FROM AUTHOR]

Previous work identified hurricane deposits in the back-barrier lagoon of Laguna Playa Grande (LPG) in Vieques, Puerto Rico, dating back over 5000 years, with periods of increased storm-induced overwash activity attributed to variability in regional hurricane climatology. In 2017, Hurricane Maria made direct landfall on LPG just below category 5 strength, providing the opportunity to revisit the site to improve upon interpretations of storm-induced deposition. Maria caused widespread wave-induced overwash of the barrier beach and extensive mangrove mortality with roughly a 40% reduction in vegetative cover along the barrier. Sediment trapping and overwash deposition occurred within ripped up and broken mangrove debris during the hurricane, which prevented sediments from being carried further landward into the lagoon. Thus, no measurable overwash deposition was observed in the larger, western portion of the lagoon where previous hurricane reconstructions are derived. Significant overwash deposition (1–27 cm thick) was observed in the smaller, eastern portion of the lagoon where human cut paths through the mangroves allowed for unobstructed flow. Early historical photos support 53% reduced vegetation in 1936 followed by revegetation towards present day that prevented sandy overwash deposits from Maria in the western side, explaining the discrepancy between previously observed hurricane overwash record compared to restricted deposition solely to locations with modern footpaths for Maria. Hurricanes occurring during the recovery-revegetation phase of such storms likely result in greater overwash deposition in back-barrier lagoons due to less barrier vegetation relative to periods with robust mangrove vegetation cover. Results highlight the important role of fringing mangrove forests in flood mitigation, and the vulnerability of back-barrier environments to enhanced flooding following both anthropogenic and event-driven vegetation loss. [ABSTRACT FROM AUTHOR]

The Terminos Lagoon Flora and Fauna Protection Area is the largest coastal lagoon in the southern Gulf of Mexico and has the largest population of bottlenose dolphins, Tursiops truncatus, reported in the region. Photo identification studies have reported permanent and seasonal residence of dolphins; however, how dolphins coexist ecologically is unknown. In the present study, from 17 dead specimens stranded on the coast of Isla del Carmen (barrier island) between 2014 and 2016, stable isotopes in the liver, heart, and muscle, which represent different time scales, were analyzed to determine residence through δ13C values and niche width and trophic coexistence through δ15N values. Differences between sexes (δ13C liver: p = 0.009; heart: p = 0.01) and age classes (δ15N muscle: p = 0.02) were found, which indicated trophic sexual segregation and changes in resource use during growth, respectively. The lack of significant differences in δ13C values indicated isotopic equilibrium between the tissues, indicating the possible permanent residence of 12 dolphins in Terminos Lagoon as a coastal ecotype (− 16‰) and a second group (five dolphins) as an oceanic ecotype (− 18‰). In conclusion, most dolphins stranded in the Terminos Lagoon are potential permanent residents of this habitat, with evidence of resource partitioning as a coexistence strategy. [ABSTRACT FROM AUTHOR]

The research of hydrographic variability can be performed using geospatial analyses of habitats that explicitly represent the distribution of physicochemical factors in different periods. In the present study, water characteristics were recorded monthly in four interdecadal sampling campaigns (1980, 1998, 2010, and 2016) in Terminos Lagoon. Based on these records, geostatistical methods and multivariate spatial analyses were conducted to describe the lagoon's spatiotemporal changes, testing the distribution of fish community attributes. Interpolation of physicochemical factors revealed directional trends of change indicative of an influence of environmental characteristics seasonality, represented in the principal components by spatial gradients on estuarine condition (PC1, salinity: 52%), habitat complexity (PC2, depth: − 63%), and water quality (PC3, pH: − 55%). The spatial classification of habitats by hierarchical clustering resulted in different environmental units representing discrete hydrographic zones (Ward's cut-off height: 0.004), such that five zones were formed in the cold fronts season (a highly hydrodynamic period) instead of four as in the rainy and dry seasons. Concordant distribution patterns of fish community attributes with the identified hydrographic zones were observed (p ≤ 0.05), suggesting that ichthyofauna responded differently to ecological variability at the seasonal scale and sorted spatially according to the local environmental heterogeneity. Overall, the continuous and discrete spatial structures found in the Terminos Lagoon provide spatially explicit scenarios of the estuarine seascape, a deep insight into the realized niche of the fish assemblages by zones in different seasons, and hydrographic characterization data to parameterize multiscale fishery models. [ABSTRACT FROM AUTHOR]

Over-summering of shorebirds refers to the phenomenon where certain species of shorebirds, primarily migratory, remain on their non-breeding grounds during the summer months for one or more years instead of migrating to their breeding grounds. The present study investigates the presence and abundance of over-summering shorebird species at four distinct sites covering 24 scanning points along the southeastern coasts of Tamil Nadu for 2017-2023. A total of 13 species were observed over-summering, with Lesser Sand Plover being the most dominant species, followed by Greater Sand Plover. Notably, 10 species were found across all four sites, while three species--Black-tailed Godwit, Bar-tailed Godwit, and Common Sandpiper--were exclusive to Dhanushkodi Lagoon, observed only during 2023. The study examined the year-wise abundance of these species, revealing a decline in over-summering shorebirds across all study sites. The Eurasian Curlew, Curlew Sandpiper, Bar-tailed & Black-tailed Godwits are the 'Near Threatened' species observed during the study. Furthermore, the research highlighted variations in Shannon species diversity index (H) location-wise and year-wise - Manoli Island (H = 2.25) in 2023; Dhanushkodi Lagoon (H = 1.8) in 2023; Valinokkam Lagoon (H = 1.63), and Pillaimadam Lagoon (H = 2.08) in 2017. Key findings are that among the study sites, in Pillaimadam Lagoon all 10 species' abundance declined; in Valinokkam Lagoon, Greater Sand Plover and Little Stint marginally increased, and eight species declined; Common Redshank and Ruddy Turnstone marginally increased in Manoli Island, while other eight species declined; Grey Plover population increased in Dhanushkodi Lagoon along with a marginal decrease in Common Redshank and Ruddy Turnstone as other species declined, over the years of study. [ABSTRACT FROM AUTHOR]

Global climate change has generated an increasing number of environmental problems, especially in Mediterranean coastal areas, such as the Po Delta (PD), where shellfish production has undergone an overall decline because of strong environmental changes. The present study is centred on assessing the fundamental ecological aspects in one of the most crucial European shellfish production lagoons, Sacca degli Scardovari (SC), addressing phytoplankton community parameters directly affecting shellfish production, namely, chemotaxonomic composition, size fractions, and total biomass, in relation to the physicochemical properties of the water column and mussel filtering activity. Our findings suggest that the phytoplankton community structure, its role within the lagoon food web and its production cycles depend on two distinct allogenic inputs, which shape the community differently and exert substantial control on shellfish production. At the same time, the suspended mussel biomass strongly controls the phytoplankton size composition, as their growth is largely supported by nanophytoplankton. As the Po River collects the drainage waters of the Italian side of the entire Alpine Arch, the phytoplankton dynamics reported here represent a useful baseline for further addressing issues of climatic changes affecting lagoon ecology. We believe that our study presents an innovative tool for the planning and management of interventions aimed at enhancing national mussel production without neglecting aspects of environmental protection or the integrity of the coastal system, with significant scientific implications. [ABSTRACT FROM AUTHOR]

Like many coastal lagoons in several countries, the "Navío Quebrado" lagoon (La Guajira, Colombia) is a very delicate and precious environment; indeed, it is a nationally recognized Flora and Fauna Sanctuary. Several factors, including climate change, are threatening its existence because of changes in the governing hydro-morphological and biological processes. Certainly, the first step to addressing this problem is to understand its hydrological behavior and to be able to replicate, via simulation, its recent history before inferring likely futures. These potential futures will be marked by changes in the water input by its tributary, the Camarones River, and by modified water exchange with the sea, according to a foreseen sea level rise pattern, as well as by a different evaporation rate from the free surface, according to temperature changes. In order to achieve the required ability to simulate future scenarios, data on the actual behavior have to be gathered, i.e., a monitoring system has to be set up, which to date is non-existent. Conceptually, designing a suitable monitoring system is not a complex issue and seems easy to implement. However, the environmental, socio-cultural, and socio-economic context makes every little step a hard climb. An extremely simple—almost "primitive"—monitoring system has been set up in this case, which is based on very basic measurements of river flow velocity and water levels (river, lagoon, and sea) and the direct participation of local stakeholders, the most important of which is the National Park unit of the Sanctuary. All this may clash with the latest groovy advances of science, such as in situ automatized sensors, remote sensing, machine learning, and digital twins, and several improvements are certainly possible and desirable. However, it has a strong positive point: it provides surprisingly reasonable data and operates at almost zero additional cost. Several technical difficulties made this exercise interesting and worthy of being shared. Its novelty lies in showing how old, simple methods may offer a working solution to new challenges. This humble experience may be of help in several other similar situations across the world. [ABSTRACT FROM AUTHOR]

Two years of monthly sampling and hydrological monitoring were performed at the outlet of a Mediterranean watershed in northern Tunisia to determine the contents of 469 pesticide active ingredients and metabolites in water and evaluate their behavior. Wadi Guenniche is a tributary of the Bizerte coastal lagoon, with a watershed area of 86 km2, which exhibits pluvial cereal, legume, and orchid cultivation and irrigated market gardening. Twenty-nine pesticide active ingredients and 2 metabolites were detected in water. Twenty-four pesticide active ingredients were authorized for use in Tunisia. Among them, 14 had never been mentioned in previous farmer surveys. Five herbicides and their metabolites were the most frequently detected: aminomethylphosphonic acid (AMPA) (100%), glyphosate (94%), simazine (94%), 2,4-D (70%), and deisopropylatrazine (DIA) (47%). The detection frequency and concentration range suggested that the phytosanitary pressure and resulting water contamination are close to those on the northern Mediterranean shore. These results, in addition to characterizing the pollution state, emphasized the need for additional studies on the use and fate of pesticides on the southern shore of the Mediterranean Sea, particularly in Tunisia. [ABSTRACT FROM AUTHOR]

A study was conducted on 31 surface sediments located in different sectors of the Egyptian Mediterranean coast. The sediments were analyzed for their pollution levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). The sediments were collected from various depths in harbors, coastal lakes, bays, and lagoons, covering the southeastern Mediterranean of the Nile Delta region. The study aimed at determining the distribution, origin, and potential ecological impact of OCP and PCB pollutants. The researchers used the SRM method of GC‐MS/MS to measure the concentration of 18 PCBs and 16 OCPs residues. The study found that the total concentration of OCPs in the samples ranged from 3.091 to 20.512 ng/g, with a mean of 8.749 ± 3.677 ng/g. The total concentration of PCB residues ranged from 2.926 to 20.77 ng/g, with a mean of 5.68 ± 3.282 ng/g. The concentration of DDTs exceeded the effect range low (ERL) (1.00) and threshold effect level (TEL) (1.19) in several stations, but it was still below the effect range median (ERM) (7.00) and the probable effect level (PEL) (4.77). This indicates a low ecological risk. The principal component analysis (PCA) was also conducted to determine the sources of all pollutants in the sediment. The PCA showed significant correlations between the concentrations of Gama‐HCH and Beta‐HCH (0.741), suggesting similar sources. Practitioner Points: OCPs and PCBs residues were analyzed in the sediment of the southeastern Mediterranean.The concentration, existence, and causes of OCPs and PCBs were investigated.OCPs and PCBs ecological risk and ecotoxicological calculation were investigated in detail.Cluster analysis, PCA, and correlation coefficient were also investigated. [ABSTRACT FROM AUTHOR]

Complete retention lagoons with wastewater reuse for agricultural purposes may offer sustainability advantages over alternative systems for small communities in semiarid regions. This study quantifies the environmental life cycle impact of adopting agriculture water reuse systems using case study data to estimate operating and building infrastructure impacts and spatial–temporal modeling to quantify resource trade‐offs. Water reuse system benefits are highly dependent on supply–storage–demand dynamics. The relative size of irrigated agricultural land to the lagoon size was the most significant factor influencing site water application rates. The benefits are sensitive to changes in air emissions occurring from the agricultural land and further emphasize the importance of proper fertilizer management when adopting water reuse systems. Wastewater reuse from complete retention lagoons reduce life cycle GHG emissions, primarily through excavation reductions, offset fertilizer use, and especially from increased crop yields from wastewater reuse at previously rainfed sites. Practitioner Points: Seven case studies and spatial–temporal modeling quantified resource trade‐offs for water reuse to reduce lagoon size.Excavation reductions and offset fertilizer compensated for emissions from electricity and construction.Crop yield increases were the largest environmental benefit of adopting water reuse.System benefits are highly dependent on supply–storage–demand dynamics.Designers should use climatic data to help estimate potential variability in available water for reuse and associated energy and crop production. [ABSTRACT FROM AUTHOR]

In a lagoon basin, the tidal prism is related to the section of its inlet by a simple monomial relationship [L. J. LeConte, "Discussion on the paper, 'notes on the improvement of river and harbor outlets in the United States,' by D. A. Watt." Trans. ASCE 55, 306–308 (1905); M. P. O'Brien, "Estuary tidal prism related to entrance areas," Civil Eng. 1(8), 738–739 (1931); and J. T. Jarrett, Tidal Prism - Inlet Area Relationships (Coastal Engineering Research Center, US Army Corps of Engineers, Fort Belvoir, VA, 1976)]. Although it is not dimensionally correct and there are sophisticated models in two or three dimensions, this relationship is widely used because of its simplicity. Having a simple relationship can be very important, especially when it is necessary to make quick, albeit approximate, evaluations. To maintain this simplicity, the same monomial relationship is often used in multi-inlet lagoons, even if the initial assumptions are not fully met. Another difficulty in applying a monomial relationship to a multi-inlet lagoon is the definition of the area of each basin. In this paper, we propose a simple Eulerian, hydrodynamic, one-dimensional approach based on the dynamic response of a nonlinear harmonic system and a harmonic analysis of the interaction between two basins in a lagoon system. With such an approach, the definition of the basin surface is overcome simply by working on topographic control basins. The study leads to the definition of a relatively simple relationship for the estimation of tidal prisms, while maintaining the flexibility of a monomial relationship. If the geometrical characteristics and the bottom friction of the inlet channel, the topographic surface of the basins and the amplitude of the tide in the open sea are known, this relationship can be used to estimate the tidal prism in individual basins. The application of this relationship to two-dimensional numerical cases and real multi-inlet lagoons shows good agreement with experimental data. [ABSTRACT FROM AUTHOR]

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