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A 120-day field study was conducted in a Malaysian mangrove ecosystem to investigate the effect of mesh size (0.20 mm, 0.50 mm, and unprotected leaf litter/open litter) on litter decomposition and associated carbon (C)/nitrogen (N) release from two mangrove species, namely Bruguiera gymnorrhiza and Rhizophora mucronata. We hypothesized that excluding fauna from various functional groups through the use of litter mesh bags would significantly impact the decay rates and related dynamics of C and N among the treatments. As expected, marked differences in the decay rate were observed among treatments, with higher decay rates in the unprotected litter. Notably, the decay rates for B. gymnorrhiza were significantly greater than those observed for R. mucronata. Microbial communities played a more substantial role in decomposition, contributing 49%, surpassing the impact of macrofauna (29% contribution) and mesofauna (25% contribution). Consistent with our hypothesis, significant differences in C and N loss were observed among treatments for both species over time. Our findings underscore the influential role of various soil faunal functional groups in litter decomposition, significantly contributing to the release of C and N. This emphasizes their crucial role in the biogeochemical cycling of C and N in blue carbon ecosystems. [ABSTRACT FROM AUTHOR]

Rapid changes in sea ice extent and changes in freshwater inputs from land are rapidly changing the nature of Arctic estuarine ecosystems. In the Beaufort Sea, these nearshore habitats are known for their high productivity and mix of marine resident and diadromous fishes that have great subsistence value for Indigenous communities. There is, however, a lack of information on the spatial variation among Arctic nearshore fish communities as related to environmental drivers. In summers of 2017–2019, we sampled fishes in four estuarine ecosystems to assess community composition and relate fish abundance to temperature, salinity, and wind conditions. We found fish communities were heterogeneous over larger spatial extents with rivers forming fresh estuarine plumes that supported diadromous species (e.g., broad whitefish Coregonus nasus), while lagoons with reduced freshwater input and higher salinities were associated with marine species (e.g., saffron cod Eleginus gracilis). West–East directional winds accounted for up to 66% of the community variation, indicating importance of the wind-driven balance between fresh and marine water masses. Salinity and temperature accounted for up to 54% and 37% of the variation among lagoon communities, respectively. Recent sea ice declines provide more opportunity for wind to influence oceanographic conditions and biological communities. Current subsistence practices, future commercial fishing opportunities, and on-going oil and gas activities benefit from a better understanding of current fish community distributions. This work provides important data on fish spatial distributions and community composition, providing a basis for fish community response to changing climatic conditions and anthropogenic use. [ABSTRACT FROM AUTHOR]

While seagrass meadows are perceived to be pertinent blue carbon reservoirs, they also potentially release methane (CH4) into the atmosphere. Seasonal and diurnal variations in CH4 emissions from a subtropical hypersaline lagoon dominated by Halodule wrightii in southern Texas, USA, on the northwest coast of the Gulf of Mexico were investigated. Dissolved CH4 concentrations decreased in the daytime and increased overnight during the diel observation period, which could be explained by photosynthesis and respiration of seagrasses. Photosynthetic oxygen was found to significantly reduce CH4 emissions from seagrass sediment. Diffusive transport contributed slightly to the release of CH4 from the sediment to the water column, while plant mediation might be the primary mechanism. The diffusive CH4 flux at the sea-air interface was 12.3–816.2 µmol/m2 d, over the range of the sea-air fluxes previously reported from other seagrass meadows. This was related to relatively higher dissolved CH4 concentrations (11.6–258.2 nmol/L) in a mostly closed lagoon with restricted water exchange. This study emphasizes seagrass meadows in the subtropical hypersaline lagoon as a source of atmospheric CH4, providing insights into the interactions between seagrass ecosystems and methane dynamics, with potential implications for seagrass meadow management and conservation efforts. [ABSTRACT FROM AUTHOR]

Although the effect of salinity on phytoplankton community structure has been studied in many coastal lagoons at different times, it has not been studied simultaneously in different lagoons that are not on the same delta but are geographically close to each other. In the present study, the effect of temporal and spatial changes in salinity on the phytoplankton biovolume, species richness, diversity, and species composition was investigated seasonally in 2020 and 2021 in 6 coastal lagoons of Marmara Basin (Türkiye). In more saline lagoons, phytoplankton biovolume, species richness, diversity, and the total number of species were lower. In lagoons which salinity values were approximate, the species composition was similar. Although the salinity in the lagoons did not show significant change seasonally, biovolume values were lower in Mert lagoon in the fall of 2020 when the salinity values were higher compared to the spring of 2021. Moreover, the considerable decrease in salinity shifted the dominant species structure from high salinity optima species to low salinity optima species in this lagoon. Other effective parameters in the seasonal distribution of dominant species were detected as temperature, dissolved oxygen, alkalinity, and nitrate nitrogen. [ABSTRACT FROM AUTHOR]

Cage farming in brackishwater resources is an emerging activity in India. Scientific planning and implementation would promote livelihood enhancement and sustainable development for the coastal community. Lagoons and backwaters are often developed for tourism and water sports activities. Identification of potential cage farming locations would improve aqua tourism and generate additional revenue for the fisherman. Hence, this study aims to locate viable cage farming locations in the Muttukadu brackishwater ecosystem, one of the most important lagoon systems on the east coast of Chengalpattu district, Tamil Nadu, for aqua tourism development. Water quality, environmental, and accessibility factors were considered the main factors for identifying suitable cage farming sites. Fourteen designated sampling points covering the lagoon were identified, and water samples were collected and analyzed at monthly intervals from December 2019 to January 2022. Each factor was further sub-classified and ranked by assigning appropriate weightage using the fuzzy analytic hierarchy process (FAHP), one of the multiple-criteria decision-making (MCDM) methods. For sustainable farming, it is important to consider ecologically sensitive areas and other constraining factors. ArcGIS Pro was used to map all the factors for identifying potential cage farming sites. The result shows the potential area available for cage farming development is about 11.52 ha, out of which 0.93 ha is highly suitable, and 10.59 ha is moderately suitable. [ABSTRACT FROM AUTHOR]

Cyanobacteria are recognised for their pivotal roles in aquatic ecosystems, serving as primary producers and major agents in diazotrophic processes. Currently, the primary focus of cyanobacterial research lies in gaining a more detailed understanding of these well-established ecosystem functions. However, their involvement and impact on other crucial biogeochemical cycles remain understudied. This knowledge gap is partially attributed to the challenges associated with culturing cyanobacteria in controlled laboratory conditions and the limited understanding of their specific growth requirements. This can be circumvented partially by the culture-independent methods which can shed light on the genomic potential of cyanobacterial species and answer more profound questions about the evolution of other key biogeochemical functions. In this study, we assembled 83 cyanobacterial genomes from metagenomic data generated from environmental DNA extracted from a brackish water lagoon (Chilika Lake, India). We taxonomically classified these metagenome-assembled genomes (MAGs) and found that about 92.77% of them are novel genomes at the species level. We then annotated these cyanobacterial MAGs for all the encoded functions using KEGG Orthology. Interestingly, we found two previously unreported functions in Cyanobacteria, namely, DNRA (Dissimilatory Nitrate Reduction to Ammonium) and DMSP (Dimethylsulfoniopropionate) synthesis in multiple MAGs using nirBD and dsyB genes as markers. We validated their presence in several publicly available cyanobacterial isolate genomes. Further, we identified incongruities between the evolutionary patterns of species and the marker genes and elucidated the underlying reasons for these discrepancies. This study expands our overall comprehension of the contribution of cyanobacteria to the biogeochemical cycling in coastal brackish ecosystems. [ABSTRACT FROM AUTHOR]

Estimations of ecosystem metabolism have rarely been used to quantify productivity in structural reductionist approaches for the description of phytoplankton composition. However, estimations of ecosystem metabolism could contribute to a better understanding of the relationship between phytoplankton composition and ecosystem functioning. To examine this, we investigated the community structure of phytoplankton in a set of Mediterranean coastal lagoons (natural and artificial) during a hydrological cycle to identify the most important environmental variables determining phytoplankton species composition. The focus of the study was on the quantification of productivity-related variables using estimations of ecosystem metabolism, such as different proxies for the estimation of the production-to-biomass ratio and of the relative importance of K- and r-strategies, which are commonly used conceptually but not quantified. Our results demonstrated differences in phytoplankton composition between seasons, due to the dominant hydrological pattern of flooding confinement in the salt marsh, and between lagoons that were caused by different levels of nutrient availability. Moreover, there was a notable decrease in the production/biomass ratio and a prevalence of K-strategists with seasonal succession, as predicted by Margalef's mandala. Thus, the results showed that estimations of ecosystem metabolism are useful for the higher frequency quantification of important ecological variables, and contribute to a better understanding of planktonic assemblages, and physical and chemical changes, in these fluctuating ecosystems. [ABSTRACT FROM AUTHOR]

Lagoons are a major coastal environment in West Africa. They provide a plethora of resources, ecosystem services and economic benefits yet a diverse set of inter-connected stressors are a challenge to their sustainability. A scoping study of the published literature pertaining to lagoons within the region was undertaken to reveal the nature of these stressors and identify gaps in knowledge, providing a resource to inform coastal management practices and reveal areas for future study. Thirty-one lagoons were identified from the scoping exercise covering Nigeria, Benin, Togo, Ghana, Cote D'Ivoire, Liberia and Senegal. The DAPSI(W)R(M) framework was used to structure analysis of the literature and surface key environmental themes. Key drivers and activities established are the use of lagoon resources and expansion of lagoon settlements. The resultant identified pressures are waste, overuse of resources, and urban growth as well as climate change. Resultant stage changes are the degradation of water quality and ecosystems with impacts for the health of lagoon organisms and humans. Responses to changes were identified as a combination of punitive legislation, participatory management approaches and solutions focused on ecosystem restoration and engineering of the physical environment. Gaps identified include research on waste and aspects of climate change mitigation and adaptation. Also notable is a lack of multi- and interdisciplinary studies that address the inter-connecting stressors experienced at lagoons and studies of multiple lagoons. Studies also tend to be problem-focused with solutions rarely presented, limiting their applicability to inform management practices. [ABSTRACT FROM AUTHOR]

Eelgrass beds provide a habitat for many high-value fishery resources, and provisioning services, one of the ecosystem services, need to be quantified. However, few examples have been evaluated spatially. We determined the distribution of eelgrass beds in Lake Notoro, a marine lagoon in Hokkaido, Japan, and quantified the provisioning services by the eelgrass beds in relation to Pandalus latirostris, a fishery resource. Acoustic measurement surveys of the eelgrass beds and catch surveys of the shrimp were conducted in July and August 2015. The relationship between catch per unit effort (CPUE) of shrimp and the distribution of eelgrass beds was shown. The estimated distribution area of eelgrass beds was 7.07 km2. Shrimp was frequently caught at water depths of 3–5 m, approximately 200 m from the edge of the eelgrass beds. The expected catch of shrimp in the fishing area of Lake Notoro in 2015 was 25.37 tons and US$ 463.6 thousand. Eelgrass beds were found to affect the fisheries production not only on the inside but also at the edge and outside. The entire coastal space should be evaluated, while considering the effect of the distribution of eelgrass beds, to quantify the provisioning services. [ABSTRACT FROM AUTHOR]

The Brazilian coastal zone comprises several types of environments, including lagoons and beaches, chosen for this study, which evaluate benthic meiofauna spatial distribution patterns in three areas, suffering different disturbance levels, throughout the Brazilian Amazon coast. Sediments from three areas (São Marcos Beach – Low level of disturbance; Calhau Beach – Medium level of disturbance; and Jansen Lagoon – High level of disturbance), in São Luís city (Maranhão, Brazil), were sampled for meiofauna assessments, granulometry and organic matter analyses. A total of 7,254 meiofaunal organisms were identified, 4,371 at São Marcos Beach, 1,856 at Jansen Lagoon, and 1,027 at Calhau Beach. The findings indicate that richness, density, and community structures differed significantly among the sampled areas. Nematoda and Copepoda were the most abundant groups. Copepoda stood out in São Marcos Beach compared to other taxa. Nematoda dominated in Jansen Lagoon. Calhau Beach presented the lowest density and richness values, with Tardigrada as the predominant meiofaunal group. Additionally, the composition of meiofauna was influenced by environmental variables, such as salinity, OM, sediment grain size and nitrate concentration, as well as anthropogenic activities taking place in the sampled areas. Considering the lack of studies in the region with this focus, it is expected that the results presented will contribute to public policies development aimed to conservation of the coastal zone in São Luís. [ABSTRACT FROM AUTHOR]

Laboratory experiments were conducted to determine the thermal tolerance of the living ostracod Cyprideis sp. from a lagoon known as Murray's Pool on the east coast of Bahrain, in the western Arabian Gulf. Our experimental trials, run in duplicate using a semi-controlled thermal incubator, demonstrate the resilience of the ostracod community to elevated temperatures. We observed that ostracod specimens begin to enter an inactive condition or become comatose at about 39.4 °C, and with increase in temperatures, half of the specimens died or did not recover at 51.8 °C. At 53.5 °C, total mortality is observed with no indication of recovery. These observations have implications for climate change predictions in the western Gulf region, as water temperatures in the lagoon reach 42 °C in summer, while the substrate temperatures on mud flats exposed during low tide exceed the lethal limit of the ostracods during the summer months. [ABSTRACT FROM AUTHOR]

The present work assesses the temporal distribution pattern and geochemical changes of rare earth elements and Yttrium, Scandium, Thorium, and Uranium delivery into the Oualidia lagoon. Two sediment cores were retrieved from the Oualidia lagoon and analyzed using neutron activation analysis. The results indicated that heavy rare earth elements are slightly enriched the sediment cores over light rare earth elements. The highest values of REEs were recorded in the top layers of the cores and depleted with depth, suggesting a possible change in factors controlling their accumulation, including mechanical, chemical, and environmental parameters such as weathering intensity, grain size, and Fe-Mn oxides. The sediments display positive Ce anomalies, which are probably related to the submarine weathering process and detrital input. Noting also the variation of hydrodynamics conditions and confinement of the upstream part of the lagoon played a key role in changing the sediment origins. Thus, further investigation of REEs origin in the Oualidia lagoon sediment is required to identify their sources, provenances, and the factors controlling their spatial and vertical distributions. However, these results provide baseline data of occurring changes in REEs geochemical composition and constitute a typical study case to understand the link between sedimentary and geochemistry processes in a lagoonal ecosystem. [ABSTRACT FROM AUTHOR]

As part of a long-term study on the effects of nitrogen (N) loading in a shallow temperate lagoon, we measured rates of N2 fixation associated with seagrass (Zostera marina) epiphytes during the summer from 2005 to 2019, at two sites along a gradient from where high N groundwater enters the system (denoted SH) to a more well-flushed outer harbor (OH). The data presented here are the first such long-term N2 fixation estimates for any seagrass system and one of the very few reported for the phyllosphere in a temperate system. Mean daily N2 fixation was estimated from light and dark measurements using the acetylene reduction assay intercalibrated using both incorporation of 15N2 into biomass and a novel application of the N2:Ar method. Surprisingly, despite a large inorganic N input from a N-contaminated groundwater plume, epiphytic N2 fixation rates were moderately to very high for a seagrass system (OH site 14-year mean of 0.94 mmol N m−2 d−1), with the highest rates (2.6 mmol N m−2 d−1) measured at the more N-loaded eutrophic site (SH) where dissolved inorganic N was higher and soluble reactive phosphorus was lower than in the better-flushed OH. Over 95% of the total N2 fixation measured was in the light, suggesting the importance of cyanobacteria in the epiphyte assemblages. We observed large inter-annual variation both within and across the two study sites (range from 0.1 to 2.6 mmol N fixed m−2 d−1), which we suggest is in part related to climatic variation. We estimate that input from phyllosphere N2 fixation over the study period contributes on average an additional 20% to the total daily N load per area within the seagrass meadow. [ABSTRACT FROM AUTHOR]

Surface waterbodies being primary source of water for human consumption are being investigated for its quality globally. This study evaluated water quality in three rivers (River Nfifikh, Hassar and El Maleh) of Mohammedia prefecture, Morocco in terms of heavy metals occurrence during two seasons of winter and spring. The heavy metals analyzed were cadmium, iron, copper, zinc, and lead. Heavy metal pollution index was derived to quantify water quality and pollution. Hazard quotient and carcinogenic risk were calculated to determine possible health risk. Modelling and prediction were performed using random forest, support vector machine and artificial neural network. The heavy metal concentration was lower in the winter season than in the spring season. Heavy metal pollution index (H.P.I.) was in the range of 1.5–2 during the winter season and 2–3 during the spring season. In the Nfifikh river, Cd2+ and Fe were the main polluting heavy metal. H.Q. was < 1 in all three rivers, which signified no adverse health effect from exposure to heavy metals. However, carcinogenic risk assessment revealed that 1 in every 100 people was susceptible to cancer during the life span of 70 years. Based on the control point reference, it was found that Mohammedia prefecture as river water was already contaminated before it entered the prefecture boundary. This was again validated with the water lagoon Douar El Marja which is located near the industrial zones of Mohammedia prefecture. Future studies are required to investigate pollution of rivers prior to their entry in Mohammedia prefecture to identify potential source and adopt mitigation measures accordingly. [ABSTRACT FROM AUTHOR]

Short-term zooplankton grazing experiments in bottles were conducted with water from 12 Danish brackish lakes covering a large gradient in salinity (0.3-17.4 ppt) as well as from mesocosms conducted in the same area with various salinities (0.5-12 ppt), two nutrient levels and low fish density (14). However, the ongoing climate change along with the already experienced extremes and a number of anthropogenic activities have increased their salinity at places and/or increased the amplitude of the salinity changes (Lengyel et al., [13]; B-Béres et al., [1]; Cortez et al., [5]). Also, in lentic environments of a drying coastal plain of Southeast Brazil, a comparison between stenohaline (i.e. narrow salinity tolerance ranges) and euryhaline (i.e. wide salinity tolerance ranges) fish species showed non-random patterns of community composition. Incubation under a range of salinities (5-57 ppt) indicated lower photosynthetic performance at increased salinity for both species, which increased their organic osmolyte contents with rising salinity stress. [Extracted from the article]

Nutrients such as nitrogen and phosphorus are typically considered detrimental to wetland values, but waterfowl can be numerous on nutrient-rich wetlands. Waterfowl were counted three to six times per year on nine treatment lagoons and associated wetlands (2,025 ha) at the Western Treatment Plant (south-east Australia) from 2000, to help maintain ecological values of this Ramsar-listed wetland as well as treating sewage for a large city (Melbourne). Up to 185,000 waterfowl were counted, varying with season, continental rainfall and lagoon operation. Nutrient levels were reduced on Lake Borrie lagoon in 2005 (as part of an Environmental Improvement Program) and restored in 2015. Waterfowl declined on Lake Borrie lagoon from 2005 when it received treated effluent not raw sewage, and increased in 2015 when it received partially treated sewage. This pattern was highly significant for total waterfowl and most species and guilds at Lake Borrie but was not replicated on other lagoons. Modelling revealed positive relationships between waterfowl numbers and nutrient concentrations, including ammonia and nitrite, to moderate levels. This shows that with careful management nutrient enrichment can have positive benefits, allowing artificial wetlands such as wastewater treatment plants to support high densities of waterbirds and the food webs that sustain them. [ABSTRACT FROM AUTHOR]

During breeding, birds have to find a balance between reproductive tasks and the need to recover their energy. Foraging movements are constrained in time and space by brood guarding and chick-rearing activities at the nesting site. Foraging behaviour differs among species according to their ecology but it can change, even markedly, among individuals of the same species according to intrinsic and extrinsic factors, such as sex, habitat, intra and inter-specific interactions. By means of individual GPS tracking, we assessed foraging behaviour of egg-incubating Kentish plovers breeding along a sandy beach bordering the Venice Lagoon. Both sexes foraged on the beach were they bred, but also in the lagoon, travelling up to 16 km far from the nest. In both habitats, individuals foraged in areas that were significantly separated from those used by other tagged conspecifics, likely lowering intra-specific competition. Males foraged mainly at daytime, in the lagoon at low tide and on the beach at high tide. Differently, females foraged mainly at night and in the lagoon, and less often on the beach exclusively during daytime, regardless of tide height. The avoidance of nocturnal foraging on the beach by females might be explained as antipredatory response to the presence of owls breeding in a pinewood adjacent the beach or to a possible diet specialization on prey that are available in the lagoon at night, irrespective to tide conditions. Overall, this study revealed an unexpected sexual difference in foraging behaviour of Kentish plover, with sexes likely facing different environmental pressures according to diurnal and nocturnal foraging. [ABSTRACT FROM AUTHOR]

This study presents the temporal and spatial effects of domestic pollution on crustacean assemblages in a protected area, Çardak Lagoon (Turkish Straits System). The samplings were performed from sandy and mud (silt + clay) bottoms between 1 and 1.8 m depths in October 2018, February, April, and June 2019. A total of 6920 specimens and 26 species (1 Isopoda, 1 Tanaidacea, 2 Mysidacea, 3 Cumacea, 5 Decapoda, 14 Amphipoda) belonging to crustaceans was found. Highest crustacea abundances were in autumn and winter. Considering the environmental variables, NO2 + NO3 (mg L− 1) and COD (mg L− 1) levels in the water had the highest correlations with abundance for the sampling periods. According to sampling points, the highest correlation value was found between anionic detergent content in the water and the abundance. Crustacean community structure was modified by environmental variables of anthropogenic origin at a higher level. Oxygen, oxygen reduction potential, NO2 + NO3, total nitrogen, chemical oxygen demand and anionic surfactant levels in water and sediment sand content % were major environmental variables affecting the crustacean abundance in the study area temporally. [ABSTRACT FROM AUTHOR]

A continuous record of paleogeographic events in southeastern Primorye has been restored based on the data from the deposits of Gniloe Lake, located on the northern coast of Nakhodka Bay, starting from 3240 cal BP. In total, five warming periods were identified: 3240–2500, 1865–1650, 1330–840, and 730–625 cal BP, and from the second half of the 17th century to the present; four periods of cooling: 2500–1865, 1650–1330, 840–730, and 625–320 cal BP; six wet periods: 3240–2500, 1865–1650, 1480–1330, 1060–840, 730–625 cal BP, and the last 280 years; and five dry periods: 2500–1865, 1650–1480, 1330–1060, 840–730, and 625–210 cal BP. According to palynological analysis, the expansion of Pinus koraiensis and dark coniferous species occurred during the second phase of the Mid-Subatlantic cooling of 1480–1330 cal BP. Over the last 150 years, the most significant changes have been associated with the anthropogenic transformation of landscapes as a result of urbanization. The area of forests and their species composition have decreased. At present, shrub thickets have occupied areas of the deforested oak forests. Based on the results of diatom analysis, seven stages of development of Gniloe Lake were established. There was a shallow semi-open lagoon at a sea level 1–1.5 m higher than the present-day one about 3240 cal BP. Cooling and a decrease in humidity about 2500 cal BP led to the formation of a slightly saline half-closed lagoon. Shallowing of the lagoon about 2000 cal BP ago was due to a decrease in the sea level. Finally, the lagoon separated from the sea about 1450 cal BP. The transformation of the lagoon into a fresh lake occurred around 1080 cal BP. During the period of cooling 838–733 cal BP the shallowing of the lake began, which continued in the Little Ice Age. The increase of the lake level associated with moderate warming and an increase in humidity began at 210 cal BP. Traces of three catastrophic events were recorded in the sediments of Gniloe Lake: a high-level storm about 3000 cal BP and 2 tsunamis around 2000 and 1560 cal BP. [ABSTRACT FROM AUTHOR]

Guest editors: Verónica Ferreira, Luis Mauricio Bini, Katya E. Kovalenko, Andre A. Padial, Judit Padisák & María de los Ángeles González Sagrario / Aquatic Ecosystem Services Introduction to ecosystem services Millennium Ecosystem Assessment The dependency of human wellbeing from ecological systems has been long recognized. The ecosystem services approach has provided background and motivated international legislation and agreements aiming to halt and reverse ecosystem degradation and biodiversity loss, such as the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES), the UN Decade on Ecosystem Restoration, and the EU Nature Restoration Law. The papers included in this Special Issue, together with reviews on ecosystem services provided by other aquatic ecosystems and organisms (e.g., Barbier et al., [2]; Macadam & Stockan, [25]; Hilt et al., [14]; Riis et al., [37]; Janssen et al., [16]), contribute to highlighting the relevance of these ecosystems and organisms to human wellbeing, and emphasizing the need for their conservation and restoration. This is followed by 6 reviews addressing ecosystem services provided by specific aquatic ecosystems and 12 reviews addressing ecosystem services provided by different groups of aquatic organisms (Table 2). [Extracted from the article]

In this review we highlight the relevance of biodiversity that inhabit coastal lagoons, emphasizing how species functions foster processes and services associated with this ecosystem. We identified 26 ecosystem services underpinned by ecological functions performed by bacteria and other microbial organisms, zooplankton, polychaetae worms, mollusks, macro-crustaceans, fishes, birds, and aquatic mammals. These groups present high functional redundancy but perform complementary functions that result in distinct ecosystem processes. Because coastal lagoons are located in the interface between freshwater, marine and terrestrial ecosystems, the ecosystem services provided by the biodiversity surpass the lagoon itself and benefit society in a wider spatial and historical context. The species loss in coastal lagoons due to multiple human-driven impacts affects the ecosystem functioning, influencing negatively the provision of all categories of services (i.e., supporting, regulating, provisioning and cultural). Because animals' assemblages have unequal spatial and temporal distribution in coastal lagoons, it is necessary to adopt ecosystem-level management plans to protect habitat heterogeneity and its biodiversity, ensuring the provision of services for human well-being to multi-actors in the coastal zone. [ABSTRACT FROM AUTHOR]

Coastal lagoons are unique ecosystems in terms of their phytoplankton community structure, due to their unstable environment in terms of biological, chemical, and physical conditions as a result of flooding and seasonality. Seasonal and spatial variations in phytoplankton are controlled by various biotic and abiotic factors. In this study, temporal and spatial changes in the phytoplankton biovolume, species richness, diversity, and Reynolds functional groups (FGs) with the effect of different environmental variables were investigated seasonally in 2020 and 2021 for seven coastal lagoons of Kızılırmak Delta (Samsun, Türkiye). Phytoplankton biovolume and species richness were lower in more saline lagoons. Moreover, their species composition was significantly different compared to lagoons with lower salinity. Phytoplankton biovolume, species richness, and diversity were generally recorded lower in spring periods. During the studied periods, 14 FGs (C, D, J, Lo, M, MP, P, S1, S2, SN, W1, W2, X1, and X2) were prominent in the total biovolume. Three FGs (C, P, and SN) were only found as dominant in Karaboğaz, Gıcı, and Cernek lagoons, and their distributions were affected by pH, nitrate–nitrogen, and low light availability (high Zmix/Zeu). Due to the seasonality and hydrology, environmental parameters and dominant FGs were generally segregated into flooding (spring), drying (summer), and transition (fall) periods. [ABSTRACT FROM AUTHOR]

Extreme events are becoming more frequent due to anthropogenic climate change, posing serious concerns on societal and economic impacts and asking for mitigating strategies, as for Venice. Here we proposed a dynamical diagnostic of Extreme Sea Level (ESL) events in the Venice lagoon by using two indicators based on combining extreme value theory and dynamical systems: the instantaneous dimension and the inverse persistence. We show that the latter allows us to localize ESL events with respect to sea level fluctuations around the astronomical tide, while the former informs us on the role of active processes across the lagoon and specifically on the constructive interference of atmospheric contributions with the astronomical tide. We further examined the capability of the MoSE (Experimental Electromechanical Module), a safeguarding system recently put into operation, in mitigating extreme flooding events in relation with the values of the two dynamical indicators. We show that the MoSE acts on the inverse persistence in reducing/controlling the amplitude of sea level fluctuation and provide a valuable support for mitigating ESL events if operating, in a full operational mode, at least several hours before the occurrence an event. [ABSTRACT FROM AUTHOR]

This work explores the role of knowledge claims and uncertainty in the public dispute over the causes and solutions to nonpoint-driven overfertilization of the Mar Menor lagoon (Spain). Drawing on relational uncertainty theory, we combine the analysis of narratives and of uncertainty. Our results show two increasingly polarized narratives that deviate in the causes for nutrient enrichment and the type of solutions seen as effective, all of which relate to contested visions on agricultural sustainability. Several interconnected uncertainties are mobilized to dispute the centrality of agriculture as a driver for eutrophication and to confront strategies that may hamper productivity. Yet, both narratives rest on a logic of dissent that strongly relies on divergent knowledge to provide legitimacy, ultimately reinforcing contestation. Transforming the ongoing polarization dynamics may require different inter- and transdisciplinary approaches that focus on sharing rather than assigning responsibility and that unpack rather than disregard existing uncertainties. [ABSTRACT FROM AUTHOR]

Knowledge of the factors controlling the growth of macrophytes is essential to forecasting their spatial distribution and management. Based on growth rates (µ), this study describes the cardinal temperatures of Egeria najas, and evaluates its growth potential. Cultures at 4 temperatures (15, 20, 25 and 30 °C) were monitored for 48 days. Plant growth was fitted to a logistic model to obtain growth rates (µ15: 0.02; µ20: 0.05; µ25: 0.10; µ30: 0.04 day−1) which were used for parameterization of the optimal temperature function, obtaining the cardinal temperatures (lower basal temperature: 5 °C; optimum temperature: 26.3 °C; upper basal temperature: 31.7 °C). Using the water temperature of the Óleo Lagoon (a tropical floodplain lagoon from which E. najas was harvested) and optimum temperature function, the seasonal variation of the E. najas µ was calculated. This procedure predicted that the highest µ are expected between September and April (rainy season); however, on average, the µ was higher between April and October (dry season). Although the temperature is of paramount importance for the growth of this species (Q10: 4.39), in aquatic environments with small thermal variations, turbidity and nutrient scarcity can decisively interfere with the growth of submerged macrophytes. [ABSTRACT FROM AUTHOR]

As human-induced environmental changes reduce niche opportunities from global to local scales, permanent shifts in species traits alter ecosystem processes. Disentangling multiscale mechanisms driving temporal changes in coastal fish biodiversity is thus critical to conservation aims. From seasonal to multiyear periods, we investigated how local environmental variation and landscape features shape temporal beta diversity (abundance-based and trait-based dissimilarities, and their components of replacement and nestedness) per zones in bays and coastal lagoons, Southeastern Brazil. At larger temporal dimensions, unaccounted processes in individual systems influenced primarily taxonomic dissimilarity, whereas functional responses to variation in marine influence varied between types of system and zones. From 2 years to seasons, taxonomic and functional dissimilarities decreased with abundance-based species replacement, and both trait-based components, respectively. Replacement processes were primarily related to marine influence (transparency, salinity, pH, and tidal phase) at larger temporal dimensions, and habitat availability (mangroves and nearby estuaries) and complexity (forest cover and landscape urbanization) in seasons. Seasonal variations in tidal phase (lower) and pH (higher), respectively, promoted taxonomic (abundance gradients) and functional (fish trait loss) nestedness under shorter environmental gradients. Spatial and temporal balances between marine influence, habitat quality, and seascape connectivity drive temporal dissimilarities in coastal fish assemblages. [ABSTRACT FROM AUTHOR]

Coral reefs encompass different habitats that have their own living communities. The present study aimed to test the hypothesis that these different kinds of habitats were characterized by specific soundscapes. Within the lagoon of Bora-Bora, acoustic recordings and visual surveys of substrate type and fish communities were conducted on four reef sites belonging to the three main geomorphological habitats (fringing reef, channel reef, barrier reef) from February to April 2021. Two acoustic parameters were measured for each site and month, during the day and at night: the peak frequency (Fpeak, in Hz) and the corresponding power spectral density (PSDpeak, in dB re 1 µPa2 Hz−1). Our results showed that each geomorphological unit could be characterized by these two parameters and therefore had a specific acoustic signature. Moreover, our study showed that a higher living coral cover was significantly positively correlated with Fpeak in the low-frequency band (50–2000 Hz) during day-time. Although biodiversity indices based on visual surveys did not differ significantly, fish communities and soundscapes were significantly different between sites. Overall, our study underlines the importance of passive acoustics in coral reef monitoring as soundscapes are habitat specific. [ABSTRACT FROM AUTHOR]

Several factors influence coral reef recovery, including availability of appropriate recruitment surface, which is provided mainly by crustose calcareous algae (CCA). Its role in coral recruitment has been amply documented, but the dynamics governing CCA availability has received little attention. This paper analyzes the benthic successional dynamics of six cover states [CCA, fleshy algae (FA), turf algae (TA), calcified articulated algae (CAA), free space, and other benthic groups] over a two-year period on patch reefs inside and outside Xcalak Reef National Park, a marine protected area (MPA) in the southern Mexican Caribbean. Recruitment tiles were used to mimic physical disturbance, and a Markov chain analysis was applied to understand the transition probabilities among benthic groups. Initial benthic succession was dominated by TA, which covered at least 75% of the surface. CCA were the dominant cover (~ 50%), at stationary distributions, at sites inside the MPA, while at the site outside the MPA the dominant cover was TA (~ 50%). Once CCA and TA occupied a space they had high probabilities of retaining it, with turnover rates ~ 1.5 years. These findings offer an entry point to the understanding at fine spatial scales of the dynamics of key benthic groups for coral recruitment and it constitutes the baseline to compare dynamics on reef adverse habitats. [ABSTRACT FROM AUTHOR]

The Venice lagoon—the largest Mediterranean coastal lagoon—is characterized by the presence at its edges of 31 "valli da pesca", types of artificial ecosystems that mime the ecological processes of a transitional aquatic ecosystem. Constituted by a series of regulated lakes bounded by artificial embankments, the valli da pesca were established centuries ago to maximize provisioning Ecosystem Services (ESs), such as fishing and hunting. As time passed, the valli da pesca underwent an intentional isolation process leading to private management. Nonetheless, the valli da pesca are still exchanging energy and matter with the "open' lagoon and today represent an essential element within the context of lagoon conservation. This study aimed to analyze the possible effects of artificial management on both ESs supply and landscape arrangements by assessing 9 ESs (climate regulation, water purification, lifecycle support, aquaculture, waterfowl hunting, wild food, tourism, information for cognitive development, and birdwatching), along with eight landscape indicators. Obtained results suggested that the valli da pesca are today ruled under five different management strategies, according to the maximized ES. Management conditions influence the landscape pattern and achieve a series of "side effects" on the other ESs. The comparison between the managed and abandoned valli da pesca highlights the importance of anthropogenic interventions for conserving these ecosystems, as the abandoned valli da pesca show a loss of ecological gradients, landscape heterogeneity, and provisioning ESs. Nevertheless, the persistence of intrinsic geographical and morphological characteristics still prevails regardless of intentional landscape molding. The result is that the provisioning ESs capacity per unit area is higher in the abandoned valli da pesca than in the open lagoon, emphasizing the importance of these confined areas of the lagoon ecosystem. Considering the spatial distribution of multiple ESs, the provisioning ESs flow that does not occur in the abandoned valli da pesca seems to be replaced by the flow of cultural ESs. Thus, the ESs spatial pattern highlights a balancing effect between different ESs categories. The results are discussed considering the trade-offs generated by private land conservation, anthropogenic interventions, and their relevance for the ecosystem-based management of Venice lagoon. [ABSTRACT FROM AUTHOR]

To investigate unexplored areas and apply methodologies suitable for monitoring volcanic activity, a pioneer study was undertaken in the crater lagoon of Vila Franca do Campo Islet to identify possible CO2 degassing zones in the marine environment. This study was carried out using a floating accumulation chamber, which to the best of our knowledge, has only been applied to lacustrine environments. A survey was carried out in the crater lagoon in August 2017, resulting in a total of 143 CO2 flux measurements. Other parameters, such as water temperature, pH, electrical conductivity, and depth, were also determined at each measuring point, covering a study area of 0.02 km2. At one of the deepest sites with higher CO2 flux values, water samples were collected at depth for determination of stable isotopic composition. Water temperatures ranged between 21.0 and 27.0 °C, pH from 8.24 to 8.89, and electrical conductivity from 52.5 to 53.9 mS/cm. As expected, due to the marine water composition, sampled waters are of the Na-Cl type. CO2 flux varied between 0.581 and 1.0 g m-2 d-1 (average = 2.967 g m-2 d-1). A single CO2 population, characterized by low CO2 fluxes, points to a biogenic CO2 origin (δ13C = −9.62‰). The estimated value for the total CO2 emitted from the water surface is 0.05 t d-1. CO2 flux measurements were also compared with the structural features that cross the tuff cone, but no clear relation was observed with fractures/faults. This methodology should be applied to other coastal marine areas, especially where anomalous gas emissions have been reported. [ABSTRACT FROM AUTHOR]

Microfacies and environmental analyses of the Yamama Formation were conducted in the Tithonian–Hautervian sequence in the Ratawi oil field of Basra city in southern Iraq. The study includes petrographic, facies, and depositional models for the study area. Seven main facies and several secondary facies have been deposited in multiple environments. Moreover, they are affected by many diagenesis processes. Those facies have noncore depths that can be monitored by matching them with their corresponding well logs to obtain their electrofacies. The facies are distinguished according to the grain or mud supported or on the appearance of the configuration facies through microscopy. After comparing them with the well logs, electrofacies are identified as the following main limestone facies (mudstone, mudstone–wackestone, wackestone, wackestone–packstone, packstone, packstone–grainstone, and grainstone facies). The formation environments in this field are divided into several environments depending on the facies and electrofacies characteristics of the formation, including a lagoon environment, open marine environment, shoal environment, and slope environment. [ABSTRACT FROM AUTHOR]

Many lagoons surrounded by reefs are partially or completely infilled with reef-derived detrital carbonate sediment. Sediment deposits in such restricted environments are archives of prevailing environmental conditions during lagoon infill. For Indonesia, no paleoenvironmental reconstructions based on Holocene lagoon sediments exist. Here we analyze the sedimentary record obtained from five percussion cores penetrating 10 m into the unconsolidated subsurface of a reef island in the Spermonde Archipelago, Indonesia. The combined compositional, textural and chronostratigraphic analyses reveal that the sedimentary infill of the lagoon underlying the island, starting 6900 years cal BP, was interrupted between 5800 and 4400 years cal BP, when sea level was ~ 0.5 m higher than at present, and monsoon intensity was lower. After the intensity of the monsoons increased to modern levels, and sea level dropped to its present position, lagoonal sedimentation was re-initiated and created the foundation for an island that built up since 3000 years cal BP. Our study provides the first geological evidence for the strong sensitivity of detrital carbonate systems in Indonesia to fluctuations in sea level and dominant wind direction. It thus sheds light on how changing environmental conditions in the context of global warming could affect the morphological development of reef systems, and thereby also habitable coastal areas. [ABSTRACT FROM AUTHOR]

In recent decades, annual cyanobacteria blooms in Florida Bay displayed spatial and temporal patterns that are consistent with changes in alkalinity and dissolved silicon in water. In early summer, the blooms developed in the north–central bay and spread southward in fall. The blooms drew down dissolved inorganic carbon and increased water pH, causing in situ precipitation of calcium carbonate. Dissolved silicon concentrations in these waters were at minimum in spring (20–60 µM), increased during summer, and reached an annual maximum (100–200 µM) during late summer. The dissolution of silica as a result of high pH in bloom water was first observed in this study. During the peak of blooms, silica dissolution in Florida Bay varied from 0.9 × 107 to 6.9 × 107 mol per month over the study period, depending on the extent of cyanobacteria blooms in a given year. Concurrent calcium carbonate precipitations in the cyanobacteria bloom region are between 0.9 × 108 and 2.6 × 108 mol per month. It is estimated that 30–70% of atmospheric CO2 uptake in bloom waters was precipitated as calcium carbonate mineral and remainders of CO2 influx were used for the production of biomass. [ABSTRACT FROM AUTHOR]

The shape of the urogenital papilla is used to visually determine the sexual dimorphism of Dormitator maculatus. However, it is occasionally not possible to determine this in practice. The objective of the present study was to propose and statistically validate other morphometric measures to fulfill this same purpose. The analysis was designed on the basis of a group of previously identified adults with urogenital papilla. It was found that the most useful morphometric measures are related to the size and weight of the species. The dorsal fins and the geometric structure of the head were also recommended as morphometric measures. The males are larger in size, they are robust with the fin 1DFL longer compared to the 2DFL fin and have a broad, elongated head. Females are smaller in size, slightly robust, with longer 2DFL fins compared to 1DFL fins, and have slender, not elongated heads. In the Alvarado lagoon, sexual differentiation in D. maculatus is important due to the selective exploitation of its gonads (mainly on females). For this reason, and to avoid errors in the identification of females for protection purposes, the results obtained are a viable alternative. [ABSTRACT FROM AUTHOR]

In the sixteenth century, Cornaro wrote a Treatise on Waters with personal observations and conclusions regarding the Lagoon of Venice, e.g., the sea level rise over the centuries, the difference between normal tides for astronomical forces and storm surges driven by meteorological factors, and water exchanges between the Lagoon and the Sea. He witnessed the continuous rise of the sea level since the Middle Ages and listed some public works made to adapt to this challenge, i.e., raising city paving and floors, and rebuilding bridges that had become too low. Cornaro dealt with the mark left by the algae on walls that was kept as an official (zero) reference of sea level. Using this key to measure flooding depths, and knowing the relationship between the algae front and mean sea level, a revision of the historical floods (from 1240 to 1867) is made to assess precise depths. During the deepest floods, it was possible to reach San Marco square by gondola and float on the square. The draught of past gondola types has been another key to interpret flood depths. From 1200 to 1500, the most extreme flooding depths were higher than that of 1966, i.e., the highest in the instrumental record since 1871; from 1500 to 1799, they have been quite homogeneous, close to the value observed in 1966; in the nineteenth century, they returned to be higher than that in 1966. Over eight centuries, the deepest historical floods exceeded 7 times by 40 cm the 1966 extreme depth. The city should be prepared to face this risk. [ABSTRACT FROM AUTHOR]

In recent years, abundant natural gas has been found in microbial carbonates in the fourth member of the Leikoupo Formation in Western Sichuan Basin. In this study, from the observation of 626 microbial thin sections, four types of microbial carbonates are classified based on the differences of mesostructures. Among them, thrombolites and stromatolites are subdivided into eight types based on the differences of microstructures. Six types of microbial microstructure association (MSA) are identified, and are mainly developed in microbial mounds. The energy of sedimentary environment and hydrodynamic conditions of them from low to high is MSA-5, MSA-1, MSA-6, MSA-3, MSA-4 and MSA-2. Because of the arid climate in the Annie Period, a restricted platform are developed in the upper sub-member of the Leikoupo Formation in Western Sichuan Basin, and the sedimentary facies are lagoon (gypsiferous lagoon or salt lake in evaporate conditions), microbial mounds, shoals, inner platform shoals and open sea from the east to the west. Microbial microstructures not only affect the pore evolution of microbial carbonate reservoirs, but also affect the diagenesis of microbial carbonate reservoirs of the fourth member of the Leikoupo Formation. [ABSTRACT FROM AUTHOR]

Tirez was a small and seasonal endorheic athalassohaline lagoon that was located in central Spain. In recent years, the lagoon has totally dried out, offering for the first time the opportunity to analyze its desiccation process as a "time-analog" to similar events occurred in paleolakes with varying salinity during the wet-to-dry transition on early Mars. On the martian cratered highlands, an early period of water ponding within enclosed basins evolved to a complete desiccation of the lakes, leading to deposition of evaporitic sequences during the Noachian and into the Late Hesperian. As Tirez also underwent a process of desiccation, here we describe (i) the microbial ecology of Tirez when the lagoon was still active 20 years ago, with prokaryotes adapted to extreme saline conditions; (ii) the composition of the microbial community in the dried lake sediments today, in many case groups that thrive in sediments of extreme environments; and (iii) the molecular and isotopic analysis of the lipid biomarkers that can be recovered from the sediments today. We discuss the implications of these results to better understanding the ecology of possible Martian microbial communities during the wet-to-dry transition at the end of the Hesperian, and how they may inform about research strategies to search for possible biomarkers in Mars after all the water was lost. [ABSTRACT FROM AUTHOR]

The endoparasitic fauna of Hoplias malabaricus (which is a species of paramount importance in the fishing and human food sectors) from Três Marias reservoir, São Francisco river, and from eleven marginal lagoons in the upper and middle São Francisco river basin, Brazil, was herein recorded for the first time. In total, 13 endoparasite species belonging to ten different families were found in 147 analyzed H. malabaricus specimens. The identified taxa comprised individuals belonging to phyla Apicomplexa–Calyptosporidae–Caplyptospora sp. (oocysts); Platyhelminthes–Trematoda–Diplostomidae (metacercariae)–Austrodiplostomum sp. and Sphincterodiplostomum musculosum, Clinostomidae (metacercariae)–Clinostomum sp., Gorgoderidae (adults)–Phyllodistomum spatula, and Eucestoda–Proteocephalidae gen. sp. (plerocercoids larvae); and Nematoda–Anisakidae (larvae)–Contracaecum sp. Types 1 and 2 and Hysterothylacium sp., Gnathostomatidae (larvae)–Spiroxys sp., Camallanidae (juveniles/adults)–Procamallanus (Spirocamallanus) inopinatus, Guyanemidae (juveniles/adults)–Guyanema baudi, and Cystidicolidae (juveniles/adults)–Cystidicoloides fischeri. Proteocephalidae gen. sp. and Contracaecum sp. Type 1 were the species presenting expressive parasitic indexes in the reservoir, in the river, and in nine of the eleven lagoons. Cystidicoloides fischeri was recorded for the first time in H. malabaricus. Guyanema baudi and S. musculosum had their geographic distribution expanded to São Francisco river basin. [ABSTRACT FROM AUTHOR]

Synechococcus are unicellular cyanobacteria susceptible to environmental fluctuations and can be used as bioindicators of eutrophication in marine ecosystems. We examined their distribution in two Moroccan lagoons, Marchica on the Mediterranean coast and Oualidia on the Atlantic, in the summers of 2014 and 2015 using 16S rRNA amplicon oligotyping. Synechococcus representatives recruited a higher number of reads from the 16S rRNA in Marchica in comparison to Oualidia. We identified 31 Synechococcus oligotypes that clustered into 10 clades with different distribution patterns. The Synechococcus community was mainly represented by oligotype 1 (clade III) in Marchica. Cooccurring clades IV and I had an important relative abundance in Marchica in the summer of 2014, which is unusual, as these clades are widespread in cold waters. Moreover, Clades VII and subcluster "5.3" formed a sizeable percentage of the Synechococcus community in Marchica. Notably, we found low Synechococcus sequence counts in the Atlantic Lagoon. These results showed that the relative abundance of Synechococcus reads is not constant over space and time and that rare members of the Synechococcus community did not follow a consistent pattern. Further studies are required to decipher Synechococcus dynamics and the impact of environmental parameters on their spatial and temporal distributions. [ABSTRACT FROM AUTHOR]

Shrimp farming increases the nutrients, especially nitrogen in the water resources reducing water quality. This study was conducted to evaluate the nitrogen dynamics in white shrimp (Litopenaeus vannamei) farms and the role of artificial lagoon (24 ha) in reducing nitrogen levels in Gomishan coastal wetland, the eastern Caspian Sea. The results indicated that at the end of the 4-month breeding period, the amounts of nitrogen and phosphorus introduced into Gomishan wetland were calculated as to 220.157 and 39 tons, respectively in a breeding area covering 830 hectares. Nitrogen values (based on nitrate) calculated based on the relationship between the basin and the discharge of the outlet channel of the site at the time of complete emptying of the farms, were calculated to be approximately 121.8 tons per breeding time that it had an important role in eliminating about 45% of nutrient pollution and reducing the concentration of dissolved nitrogen. Moreover, nitrogen isotopic trace was observed in shrimp samples, in similar levels in the samples of both shrimp pond and lagoon, which emphasizes the role of feeding from natural food, especially benthic fauna. Overall, due to the decline of Caspian Sea water level, Gomishan coastal wetland is drying, and the output of shrimp farms is currenly the only source supplying water for the wetland. Hence, appropriate management strategies could minimize the amounts of nutrients into the natural water whilst aiding wetland's survaival. [ABSTRACT FROM AUTHOR]

The Navachiste complex (NAV) is impacted by neighbored human activities and is located in the southwestern coastal zone of the Gulf of California. The study determines the trace metal (TM) and organochlorine pesticides (OCP) health risk content in the edible tissue of Sphoeroides spp. from NAV. The daily intakes (EDI), target hazard quotient (THQ), hazard index (HI), and carcinogenic and non-carcinogenic risks were calculated. Twenty OCP and seven TM were detected. Cd, Cu, Fe, Mn, Pb, and Zn were above MRLs. The γ‒Chlordane was the most frequent OCP. The highest average concentration was for α‒HCH, followed by γ‒chlordane. With the high ratios of γ‒HCH, p, p′‒ DDD and p, p′‒DDD, and the absence of p, p′‒ DDT, the higher ratios for dieldrin and endrin than for aldrin, α‒ chlordane, γ‒chlordane, heptachlor, and heptachlor epoxide indicates historical contamination. In contrast, the residual products of methoxychlor, endosulfan, and its isomers indicate endosulfan's recent use. The TM EDI, THQ > 1 (at 120 g day−1), and the ILCR (> 1 × 10–6) were above minimum levels, showing a high-risk potential for cancer development in the long term. [ABSTRACT FROM AUTHOR]

The present paper reports the site of attachment preference, overlapping and partitioning of niche among different life stages of parasitic isopod Cymothoa indica Schiöedte and Meinert, 1884 in the Gobiidae fish Glossogobius giuris (Hamilton 1822) collected from the Chilika lagoon, India. Out of 2113 host fishes, 176 were found to be infected by the parasites. Out of the 233 different life stages of the parasites examined, 89 were female, 104 were male, and the rests were juveniles. 100% of the females, 84.6% of the male and 72.5% of the juveniles were found to be attached to the buccal cavity, while the rest of the males and juveniles were attached to the branchial cavity. In most cases, there was niche overlapping, leading to competition for the resources. Females preferred more specialized niches as compared to males and juveniles. In a few instances, there is niche partitioning, as shown by the male and juveniles. There is a negative correlation between the number of parasites found in the body of the fishes and the weight of the host fishes. This manuscript also provides a brief description of the different life stages of this parasite in the above-mentioned host collected from the same lagoon. [ABSTRACT FROM AUTHOR]

In this study, we explored the association between land use and fish species richness on 52 coastal lagoons in Southeast and South Brazil. We measured the proportion of agriculture and urbanization around lagoons over 26 years and used the coefficient of variation (CV) as a surrogate of the temporal land cover variability. We compiled species occurrences from primary data, from the literature and from museum records, and assigned each recorded species to different habitat use groups: benthic/bottom or water column, and littoral or limnetic zones. In the Southeast, where most lagoons are subject to marine influence, richness was negatively associated to agriculture and positively associated to urbanization. In the South, where freshwater lagoons predominate, richness was negatively associated to urbanization and positively associated to agriculture. The results suggest that fish communities from freshwater coastal lagoons are more sensitive to land use than brackish lagoons. Differently from brackish lagoons, that are colonized by both freshwater and marine species, freshwater lagoons rely on neighboring lagoons as species donors. However, this apparent resilience of the brackish lagoons must be regarded with caution, since the increase in marine connections due to artificial sandbar openings may impair freshwater species with time. [ABSTRACT FROM AUTHOR]

Global climate change is expected to affect precipitation patterns over Southeastern South America, increasing the number and intensity of heavy rainfalls. We aimed to identify short-term effects of very heavy rainfall events (VHREs) on abiotic and biological indicators of water quality in Rodrigo de Freitas Lagoon (RFL; Rio de Janeiro, Brazil). Our hypothesis is that VHREs alter water parameters reducing the overall quality of lagoon. A before-and-after effect design was applied by compiling mean weekly data of four abiotic and three biological indicators for 1st and 2nd weeks before and 1st and 2nd weeks after VHRE. One extreme and 15 VHREs were detected from 2018 to 2019, directly interfering on the stormwater input into RFL. Particular water conditions after VHREs were mainly related to increased Escherichia coli density and decreased dissolved oxygen and phytoplankton abundance. Moreover, shifts in relative contribution of phytoplanktonic groups were significantly detected. We successfully identified short-term effects of VHREs on biological and hydrological indicators of water quality in RFL, which have partially supported our hypothesis. Predictions of increased rainfall intensity and frequency of extreme events may lead to harsher and unpredictable changes in ecosystem functioning and lagoon conditions that may impair aquatic biodiversity and fisheries. [ABSTRACT FROM AUTHOR]

Shallow coastal habitats are ruled by fluctuating environmental conditions, which lead to shifts in fish communities. Functional groups of habitat use and trophic strategy were used to address the responses of fish composition and diversity, since comparisons of rich tropical systems are often complex through species-based approaches. We hypothesized that fish groups will have specific affinities in response to the prevailing environmental conditions, especially those reflecting the prevalence of oceanic or estuarine conditions, where guilds of habitat use would perform better as indicators. Despite the importance of other environmental factors (i.e. temperature and transparency), salinity was the key structuring factor irrespective of the coastal lagoon. Although harbouring the greatest biomass of piscivores, the harsh environmental conditions at Araruama lagoon were related to low diversity. A great number of indicator species, typically of marine affinity, was found at the Saquarema lagoon, probably due to the continuous and broad connection to the sea leading to the predominance of euhaline conditions. Despite the presence of non-native species (i.e. Oreochromis niloticus), the Maricá lagoon function as an important refuge for freshwater groups. Our results stressed the key role played by coastal lagoons of varied water conditions in supporting fish diversity at regional levels. [ABSTRACT FROM AUTHOR]

Submarine groundwater discharge (SGD) is a critical land-ocean process in coastal areas and an essential component of the global hydrological cycle. Thus, hydrologists and oceanographers are paying more attention to SGD. SGD transports large amounts of materials into the ocean, including nutrients, carbon, and metals, and thus plays a vital role in the cycling of marine materials and affects the ecological environments of nearshore areas. This study examined the research status of SGD and its environmental effects in China, including a systematic analysis of radium activities and nutrient contents in groundwater, SGD rates, and the contribution of SGD to nutrients in various coastal ecosystems (bays, estuaries, continental shelves, and lagoons). The results showed the median concentrations of groundwater nutrients (dissolved inorganic nitrogen DIN, dissolved inorganic phosphorus DIP, and dissolved inorganic silicon DSi), SGD rates, and SGD-derived DIN and DIP in estuarine areas far exceeded those in the other three ecosystems studied. This result could be attributed to the complex hydrodynamic conditions of estuary areas as well as the considerable influence of human activities. Conversely, the lowest SGD rates and three inorganic nutrient species via SGD were observed in large scale continental shelves. SGD-derived nutrient fluxes were comparable to riverine inputs along the entire coast of China, which significantly affected the nutrient budget, nutrient composition, and primary productivity of coastal waters. Finally, this review suggests further research of SGD in three aspects: (1) accurate assessment, (2) its environmental effects, and (3) its regulatory strategies. [ABSTRACT FROM AUTHOR]

The aim of this study was to reveal the diversity of parasitoids and ascertain tritrophic parasitoid-host aphid-host plant interactions in a lagoon habitat very close to orchards, vegetable gardens, and cereal fields in the Çanakkale Province of northwest Turkey between April and September from 2020 to 2021. In total, 23 tritrophic parasitoid-host aphid-host plant interactions, including new association records for Europe and Turkey, were revealed on 12 parasitoid species belonging to six genera from the subfamily Aphidiinae (Hymenoptera: Braconidae) reared from 15 aphid species (Hemiptera: Aphididae) on 17 host plants from different plant families. Also, we present three tritrophic parasitoid-host aphid-host plant interactions new for Europe and five tritrophic interactions new for Turkey. Of the identified parasitoid species, Aphidius (Aphidius) artemisicola Tizado et Nunez-Perez, 1994 is recorded for the first time for the parasitoid fauna of Turkey. A morphological diagnosis of the newly recorded parasitoid is provided. The results of this study of the tritrophic interactions between parasitoids and their aphid hosts on host plants in a lagoon habitat enable us to more meaningfully interpret these interactions and provide data of potential significance for the biological control of pest aphids in the region. These results showed that research on the interactions of parasitoids and their host aphids on non-crop host plants in non-crop areas close to crop fields can yield data of potential significance for the biological control of aphids in agriculture. [ABSTRACT FROM AUTHOR]

The particular structure and configuration of the Venice lagoon represents a paramount case study concerning coastal flooding which affects natural, historical/cultural properties, together with industrial, commercial, economical and port activities. In order to defend Venice (and other sites) within the lagoon from severe floods, the Italian Government promoted the construction of a complex hydraulic/maritime system, including a movable storm surge barrier named Experimental Electromechanical Module (MoSE), to be activated when specific water levels occur. When the MoSE barriers are raised, the only access to the lagoon for commercial and cruise ships is represented by the Malamocco lock gate, provided that suitable safety conditions (involving the significant wave height) are satisfied. In addition, the Italian Government has recently established that, in the near future, large ships will always have to enter/exit the lagoon only through the Malamocco entrance. In turn, the navigation within the Venice lagoon is (will be) controlled by the combined MoSE-Malamocco system, ruled by both univariate and bivariate paradigms/guidelines. As a novelty, in the present work, for the first time, the statistics of significant wave heights and water levels in the Venice lagoon (both univariate and bivariate ones) are investigated: in particular, these variables turn out to be dependent, and their joint occurrence (statistically modeled via Copulas) can determine the stop of ship navigation, yielding significant economic losses. Here, univariate and bivariate Return Periods and Failure Probabilities are used to thoroughly model the statistical behavior of significant wave heights and water levels, in order to provide useful quantitative indications for the management of the tricky hydraulic, maritime and economical system of the Venice lagoon. [ABSTRACT FROM AUTHOR]

The influence of hydrodynamic factors on the formation of zoobenthos communities in the coastal zone exposed to active wind-wave mixing, as well as in the deep part of water bodies characterized by the silt accumulation is considered for the Curonian Lagoon. The features of the qualitative and quantitative distribution of zoobenthos and their effect on determining the water quality using zoobenthos parameters are analyzed. Recommendations are given for the placement of hydrobiological monitoring stations based on zoobenthos parameters. [ABSTRACT FROM AUTHOR]

Tropical coastal lagoons are important ecosystems that support high levels of biodiversity and provide several goods and services. Monitoring of benthic biodiversity and detection of harmful or invasive species is crucial, particularly in relation to seasonal and spatial variation of environmental conditions. In this study, eDNA metabarcoding was used in two tropical coastal lagoons, Chacahua (CH) and Corralero (C) (Southern Mexican Pacific), to describe the benthic biodiversity and its spatial–temporal dynamics. The distribution of benthic diversity within the lagoons showed a very particular pattern evidencing a transition from freshwater to seawater. Although the two lagoon systems are similar in terms of the species composition of metazoans and microeukaryotes, our findings indicate that they are different in taxa richness and structure, resulting in regional partitioning of the diversity with salinity as the driving factor of community composition in CH. Harmful, invasive, non-indigenous species, bioindicators and species of commercial importance were detected, demonstrating the reach of this technique for biodiversity monitoring along with the continued efforts of building species reference libraries. [ABSTRACT FROM AUTHOR]