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The growth of the human population causes significant harm to ecosystems, directly affecting the biological diversity of coastal areas by replacing natural habitats with artificial structures such as breakwaters, ports, and marinas. The hard substrate from those marine facilities lacks the topographic complexity of natural habitats. Because of that, artificial habitats usually do not support a diverse community to the same extent as rocky shores in the surroundings. To address this issue and bring a strategic solution to the improper disposal of shell waste from aquaculture farms, we evaluated how increasing the environmental heterogeneity of walls by incorporating mussel and oyster shells on artificial concrete affected the diversity of sessile organisms from the subtidal zone. Adding shells to concrete positively affected ascidians' richness. Substrates with added shells supported more species than flat substrates in total. They promoted species that did not occur on flat substrates that simulated the traditional walls of marinas and harbors. However, it did not affect the number of bryozoans and the average species richness. Consequently, incorporating shells resulted in communities with completely distinct structures from those on flat substrates. Adding shells affected the community structure, reducing the dominance by the exotic bryozoan Schizoporella errata, and promoting the occurrence of other groups, such as ascidians. Using shell residues from aquaculture on marina walls adds substrate for colonization. Still, it is also likely to provide refuges for fragile and vulnerable organisms, like crevices and pits in natural habitats. Because of that, the increment in diversity was mostly group-specific and restricted to ascidians. This research reinforces the importance of creating complex artificial coastal structures, inspired by the blue economy, for a more heterogeneous coverage of sessile communities and reduced presence and dominance of exotic species. Thus, the strategy tested here, besides the effects on the sessile community, also supports efforts to reduce inappropriate waste disposal in the environment.

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Territorial space conflicts (TSCs) in coastal zones stem from the intricate interaction between the land-sea dual system, significantly impacting the sustainable development of these areas. To accurately identify TSCs, our study proposed a theoretical framework based on a land-sea interaction perspective. We also assessed TSCs using the territorial space conflicts index and a social network analysis model. We demonstrated the proposed spatial conflicts assessment methodology through a case study of Wenzhou, a typical city on the east coast of China. Our results indicate that the distribution of TSCs gradually decreased from the coastal zone to the inland zone, with significant variation in the distribution of different conflict types across different zones. The findings also reveal that territorial space use had diverse impacts on the space conflict network, making it urgent to take targeted measures. In the future, it is crucial to comprehensively consider the overall pattern and distribution characteristics of current TSCs, as well as the spatial spillover effect of the overall network, to develop targeted coping strategies and regulation mechanisms that promote the integration and high-quality development of coastal territorial space systems. To maintain a sustainable coastal zone process, we proposed a set of optimization paths for alleviating TSCs and promoting the coordinated development of land and sea regions in China based on our study.

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Plastic is the most abundant marine anthropogenic debris in the ocean and is of serious global environmental concern. Projects aimed at monitoring plastic pollution quantities are key in evaluating the success of reduction. This study provides baseline information on the quantities of marine debris found on the island of Príncipe in the Gulf of Guinea in the Atlantic coast of Central Africa. A total of 13,196 items were collected with 64.5% of these items being plastic. Plastic pieces the size of 2.5-50 cm made up 20.8% of all plastic items, followed by plastic bags (13.3%) and fishing material (11.39%). The density of mesoplastic items (<25 and >5mm) ranged between 0 and 6.78 items m-2. Beach location, community presence, and beach level (for turtle-nesting beaches) were important factors in explaining differences in plastic abundance and density around the island. Our results highlight the significance of high plastic pollution accumulation on remote islands.

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BACKGROUND & OBJECTIVES: Aedes albopictus and Aedes aegypti are important vectors of dengue and many other arboviral diseases in tropical and sub-tropical locations. Both vectors are tolerant of salinity in the dengue-endemic coastal Jaffna peninsula of northern Sri Lanka. Aedes albopictus pre-imaginal stages are found in field brackish water habitats of up to 14 parts per thousand (ppt, gL-1) salt in the Jaffna peninsula. Salinity-tolerance in Aedes is characterized by significant genetic and physiological changes. Infection with the wMel strain of the endosymbiont bacterium Wolbachia pipientis reduces dengue transmission in the field by Ae. aegypti, and the same approach is also being considered for Ae. albopictus. In this context, we investigated natural Wolbachia infections in brackish and fresh water field isolates of Ae. albopictus in the Jaffna district. METHODS: Aedes albopictus collected as pre-imaginal stages using conventional ovitraps in the Jaffna peninsula and adjacent islands of the Jaffna district were screened by PCR utilizing strain-transcending primers for the presence of Wolbachia. Wolbachia strains were then further identified by PCR using strain-specific primers for the Wolbachia surface protein gene wsp. The Jaffna wsp sequences were compared by phylogenetic analysis with other wsp sequences available in Genbank. RESULTS: Aedes albopictus were found to be widely infected with the wAlbA and wAlbB strains of Wolbachia in Jaffna. The partial wAlbB wsp surface protein gene sequence in Jaffna Ae. albopictus was identical to a corresponding sequence from South India but different from that in mainland Sri Lanka. INTERPRETATION & CONCLUSION: Widespread infection of salinity-tolerant Ae. albopictus with Wolbachia is a factor to be considered when developing Wolbachia-based dengue control in coastal areas like the Jaffna peninsula.

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Microplastics are distributed in the environment and are considered emerging pollutants because they are not regulated by legislation. This article aims to know the current state of knowledge regarding microplastic pollution in coastal areas of Colombia. Therefore, a detailed search was carried out in databases such as Scopus, Google Scholar, and university repositories collecting scientific and academic information published between 2000 and March 2022. As a result of the review, the presence of microplastics in coastal areas of Colombia was identified, particularly in the water, sediments, and fish, thus evidencing the contamination in coastal ecosystems, where the Caribbean coast is the area with the highest amount of microplastics in sediments, especially Cartagena (249-1387 particles/m2) and Santa Marta (144-791 particles/m2). It was also found that of 302 species of fish, 7% contained microplastics in the Ciénaga Grande of Santa Marta. In the studies, on the other hand, it was observed that there is no standardized methodology; each researcher chooses a different approach according to the scientific literature. The studies showed that the most abundant microplastics were secondary microplastics, of which polypropylene and polyethylene are predominant due to their different applications in society. This review will serve as a baseline for future research on microplastics in coastal areas of Colombia and will identify the challenges and realities of the country in the face of these emerging pollutants.

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The great current challenge for the conservation and use of natural resources refers to global climate change, because of its impacts felt in different intensities at global, regional, and local spatial scales. Within the system of environmental protection areas in Brazil, the extractive reserves ensure the sustainable use of natural resources by traditional populations, thus maintaining the cultural and biological aspects of a region. Such populations, being in close management of the surrounding environments, tend to perceive changes in ecological processes that many need for their livelihoods. The use of this perception of local populations in conjunction with academic research evidence has a high potential to allow a whole and systemic view of possible changes in natural phenomena. This study developed an integrated analysis of scientific evidence and local perceptions to understand the variation of precipitation in a community inserted in an extractive reserve in the eastern Amazon. We used 30 years of precipitation data from the Brazilian National Institute of Meteorology - INMET, the Southern Oscillation Index - SOI, and the Atlantic Meridional Mode Index - AMM. Furthermore, we applied a form to measure the population's perception of possible changes in rainfall cycles in the region. The meteorological data indicate that the region of the community has been presenting a rainfall reduction; however, people in the community do not perceive this trend. Although it is public knowledge that the global climate is undergoing changes, a fact noted after the integrating analysis of scientific evidence with local knowledge in Resexmar Soure is that the perceptions of traditional populations often focus on smaller temporal and spatial scale visions.

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Introduction: To clarify the effects of microtopography on plant growth and soil water, salt and nutrient characteristics of saline soils in mudflats within muddy coastal zones and explore suitable microtopographic modifications. Methods: Six microtopographic modification patterns, namely, S-shaped, stripe-shaped, pin-shaped, stepshaped, dense stripe-shaped and crescent-shaped patterns, were established in the coastal mudflats of the Yellow River Delta. The soil water, salt, ion, total carbon, total nitrogen, and total phosphorus contents and their ecological stoichiometric characteristics were measured and analyzed after theimplementation of different microtopographic modification patterns, with bare mudflats as the control. Results: The results showed that microtopographic modification significantly changed the soil water and salt contents and the soil total carbon, total nitrogen and total phosphorus contents. Compared with the bare ground, microtopographic transformation significantly promoted the growth of the pioneer plant Suaeda salsa, significantly increased the soil water and nutrient contents, and significantly decreased the soil salinity. The soil salinity was mainly reduced by Na+ and Cl- ions. The soil salinity and nutrient contents gradually decreased with increasing soil depth, indicating the occurrence of surface aggregation. Compared to that of the bare ground, the soil C/N was significantly lower and the N/P was significantly higher in the microtopographic treatments, and the overall performance suggested soil N limitation. The ions contained in the saline soil were dominated by Na+ and Cl-, followed by Mg2+ and SO4 2-, with lower contents of K+, Ca2+ and HCO3 -. Among the six microtopography modification patterns, the crescent-shaped pattern best promoted vegetation restoration. This pattern was the most effective in reducing soil salinity, with a 98.53% reduction in soil salinity compared with that of bare ground, followed by the pin-shaped pattern. Compared with that in the bare ground samples, the nutrient content in the samples from the step-shaped modification increased by 23.27%; finally, the S-shaped, step-shaped and dense stripe-shaped patterns performed poorly in terms of plant restoration and soil improvement. Discussion: It is suggested that a crescent-shaped pattern should be considered first when carrying out microtopographic transformation on the beaches of the Yellow River Delta, followed by stripe-shaped and pin-shaped patterns. The dense strip-shaped should not be adopted.

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Bathymetric LiDAR technology is a technology used for simultaneous data acquisition regarding the morphology of the bottom of water reservoirs and the surrounding coastal zone, realized from the air, e.g., by plane or drone. Contrary to the air topographic LiDAR, which uses an infrared wavelength of 1064 nm, bathymetric LiDAR systems additionally use a green wavelength of 532 nm. The green laser can penetrate the water, which makes it possible to measure the depth of shallow water reservoirs, rivers, and coastal sea waters within three Secchi depths. This article presents the theoretical basis for the construction of a green laser. Against the background of other methods of measuring the bottom of water reservoirs, the technology using waves from the visible light range is presented in detail in the assessment of the bottom morphology of shallow water reservoirs. The possibilities of using green laser in lidar bathymetry implemented in particular in non-navigable regions are shown. The results of the researchers' work on river processes (erosion, sedimentation), design of stream restoration, determination of morphometric parameters of the riverbed, as well as assessment of the topography of the marine coastal bottom zones are summarized. The development direction of lidar bathymetry is discussed.

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There is always an adamant need to comprehend and draw the complex challenges of sustainability in order to help organize studies, due to the increasing human-related pressures on coastal zones. Hence, by formulating such a comprehensive framework, it could be possible to anticipate changes and support managerial decisions, as well as the degree of resilience of the region's environment. One of the approaches utilized in littoral or coastal zones is the conceptual framework of drivers, pressure, status, impact, and responses (DPSIR)..Qeshm Island, the largest island in the Persian Gulf, is accounted for being the most vital and strategic areas of the mentioned region. In recent decades, Qeshm has become one of the major cultural, natural, geological, and tourism hubs of the country due to its unique regional characteristics, along with its biodiversity and environmental sensitivity. Thereby, in the present research, a combined approach shall be followed to explore the resilience of the marine environment on the northern coast of Qeshm Island by taking advantage of the socioeconomic criterion. In this respect, the conceptual framework of the DPSIR model is utilized in combination with the structural equation model (SEM-PLS) (or partial least squares), which is one of the nonexperimental techniques, to quantify the results in the best manner possible. On the basis of the fuzzy cognitive map (FCM), the regional economic index bearing the weights of 0.62, 0.62, and 0.5, along with an institutional-managerial and biological index, respectively, denotes a two-way positive correlation, whereas this factor has a two-way, but adverse correlation, relationship with a weight of 0.65 in terms of the sociocultural index. Similarly, there is also a one-way and negative relationship, as to the economic index, with a weight of 0.69 which is in relevance with the physio-chemical index.

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Geobacter, as a typical electroactive microorganism, is the "engine" of interspecies electron transfer (IET) between microorganisms. However, it does not have a dominant position in all natural environments. It is not known what performs a similar function as Geobacter in coastal zones. Metagenomic and metatranscriptomic analysis revealed that Desulfovibrio and Methanobacterium species were the most abundant in electrochemically active aggregates. Metatranscriptomic analysis showed that Desulfovibrio species highly expressed genes for ethanol metabolism and extracellular electron transfer involving cytochromes, pili and flagella. Methanobacterium species in the aggregates also expressed genes for enzymes involved in reducing carbon dioxide to methane. Pure cultures demonstrated that the isolated Desulfovibrio sp. strain JY contributed to aggregate conductivity and directly transferred electrons to Methanothrix harundinacea, which is unable to use H2 or formate. Most importantly, further coculture studies indicated that Methanobacterium strain YSL might directly accept electrons from the Desulfovibrio strain JY for the reduction of carbon dioxide to methane in the aggregate. This finding suggested that the possibility of DIET by Desulfovibrio similar to Geobacter species in conductive methanogenic aggregates can not be excluded.

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Ecosystem services (ESs) have received widespread attention worldwide for their potential to solve sustainability issues. However, extensive land use and land cover change (LUCC) driven by human activities has raised concerns regarding its impacts on ESs, especially in coastal zones. More importantly, spatial-temporal changes, their coupling relationships with LUCC, and their underlying drivers have not been thoroughly analyzed. This study focuses on China's coastal zones to investigate the spatial-temporal changes of ecosystem service multifunctionality (ESM) from 2000 to 2018. Coupling coordination degree (CCD) analysis of the relationship between ESM and comprehensive intensity of land use was applied to identify coastal cities with low-level coordination and their main drivers in 2018. The results show that: (1) the proportion with high levels of ESM decreased by 1.01% from 2000 to 2010 and then increased by 3.29% from 2010 to 2018; (2) the ESM of China's coastal zones present significant spatial heterogeneity, and the low levels of ESM are mainly distributed in the north and urban areas, while most areas in the southern coastal zones have high levels of ESM; (3) forest land is the leading land cover type for ESM, and China's forest conservation policies significantly contribute to the increase in ESM; (4) the CCD of most cities in the southern coastal zones, apart from Shanghai and the Pearl River Delta, is at a relatively high level and experiences no significant changes, while most cities in the northern coastal zones display an improving trend; (5) the land use type, landform type, and leaf area index are the determinants of ESM, and the annual average temperature, population density, and surface elevation are the greatest influences on the CCD. The findings of this study can inform ecological conservation and landscape planning and are beneficial to the sustainable development of coastal zones in China.

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Transitional coastal zones are subject to high degrees of temporal fluctuation in environmental conditions, with these patterns varying in space. Gaining an in depth understanding of how sessile organisms cope with and respond to such environmental changes at multiple scales is needed to i) advance fundamental knowledge, ii) predict how organisms may react to stressors and iii) support the management of halieutic resources in transitional coastal areas. We addressed this question using mussels (Mytilus galloprovincialis) as model system. Valve-gaping sensor were deployed at multiple sites within the southern Venice Lagoon over a period of 6 months, to investigate the existence of periodicity in valve-gaping and its relationship with environmental variables, such as temperature and chlorophyll-a. Gaping behaviour was found to have periodic rhythms, of ~12 h and ~ 24 h, which were most pronounced in the inner part of lagoon part and were strongest during summer months. In autumn, the dual periodicity became weaker and mostly the 12 h remained. Gaping was closely linked with tide, but the relationship in terms of phasing varied upon location. Surprisingly, no clear direct relationships were found with chlorophyll-a, but food delivery may be mediated by tide itself. The results highlight the heterogeneity of behaviour and the endogenic nature of circadian rhythms in space and time. These findings have important implications for management of transitional areas where tidal alteration may have impacts on key behaviours, and emphasize the importance of characterizing their rhythms before using these as stress indicator. Moreover, the described tidal relationships should be included in growth models of bivalves in these systems.

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Drinking-water fluorosis is universal along coastal zones, and the seawater or brine water intrusion is occasionally supposed to enrich groundwater fluorine levels. However, there is no conclusive proof, and the laws and mechanisms remain ambiguous. Granite, the common fluorine-bearing rock, is selected and experimented upon to reveal the characteristics and laws of fluorine's leaching ability during the intrusion of seawater. The fluorine-leaching ability increases with the increasing ratios of seawater or brine water, the increasing levels of NaCl or NaHCO3, and the decreasing levels of CaCl2. Such results directly confirm that seawater or brine water intrusion, as well as the conditions of higher Na+, HCO3- and lower Ca2+, promotes fluorine-leaching ability from granite. The intensities of SiOSi, SiOFe, SiOAl bonds decrease but those of OH bonds increase with a higher ratio of seawater or brine water, the higher levels of NaCl or NaHCO3, and the lower levels of CaCl2. This indicates the more silicate dissolution and stronger OH-F exchange evoked by seawater or brine water intrusion are responsible for the higher fluorine-leaching from granite. Therefore, the process of seawater or brine water intrusion should be important for the groundwater enrichment dynamics along coastal zones.

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Coastal areas have been increasingly affected by human activities, marine pollution and climate change are among the most important pressures affecting these environments. Human-induced pressures occur in a cumulative way and generate additive, antagonistic or synergistic effects. Knowledge on synergistic effects is crucial to coastal zone management, since they may imply a change in human uses of these systems, as well as dedicated action plans in order to reduce hazards and environmental risks. In this work, we provide an overview of the available literature on synergistic effects between climate change and chemical pollution, and discuss current knowledge, methodological approaches, and research gaps and needs. Interactions between these two pressures may be climate change dominant (climate change leads to an increase in contaminant exposure or toxicity) or contaminant-dominant (chemical exposure leads to an increase in climate change susceptibility), but the mechanistic drivers of such processes are not well known. Results from a few meta-analyses studies and reviews showed that synergistic interactions tend to be more frequent compared to additive and antagonistic ones. However, most of the studies are individual-based and assess the cumulative effects of a few contaminants individually in laboratory settings together with few climate variables, particularly temperature and pH. Nevertheless, a wide diversity of contaminants have already been individually tested, spanning from metals, persistent organic pollutants and, more recently, emergent pollutants. Population and community based approaches are less frequent but have generated very interesting and more holistic perspectives. Methodological approaches are quite diverse, from laboratory studies to mesocosm and field studies, or based on statistical or modelling tools, each with their own potential and limitations. More holistic comparisons integrating several pressures and their combinations and a multitude of habitats, taxa, life-stages, among others, are needed, as well as insights from meta-analyses and systematic reviews.

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Coastal zones and many small islands are highly susceptible to sea-level rise (SLR). Coastal zones have a large exposed population and integrated high-value assets, and islands provide diverse ecosystem services to millions of people worldwide. The coastal zones and small islands affected by SLR are likely to suffer from submergence, flooding and erosion in the future. However, very few studies have addressed the heterogeneity in SLR changes and the potential risk to coastal zones and small islands. Here we used the mean sea level (MSL) derived from satellite altimetry data to analyse the trends and accelerations of SLRs along global coastal zones and small islands. We found that except for the Antarctic coastal zone, the annual MSL within 50 km of the coasts presented an increasing trend of 3.09 ±â€¯0.13 mm a-1 but a decreasing acceleration of -0.02 ±â€¯0.02 mm a-2 from 1993 to 2017. The highest coastal MSL trend of 3.85 ±â€¯0.60 mm a-1 appeared in Oceania, and the lowest trend of 2.32 ±â€¯0.37 mm a-1 occured in North America. Africa, North America and South America showed acceleration trends, and Eurasia, Australia and Oceania had deceleration trends. Further, MSLs around global small islands reflected an increasing trend with a rate of 3.01 ±â€¯0.16 mm a-1 but a negative acceleration of -0.02 ±â€¯0.02 mm a-2. Regional heterogeneity in the trends and accelerations of MSLs along the coasts and small islands suggests that stakeholders should take discriminating precautions to cope with future disadvantageous impacts of the SLR.

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Estuarine and coastal regions are often characterized by a high variability of suspended sediment concentrations in their waters, which influences dredging projects, contaminant transport, aquaculture and fisheries. Although various three-dimensional open source software are available to model the hydrodynamics of coastal water with a sediment module, the prediction of the fate and transport of cohesive sediments is still far from satisfied due to the lack of an efficient and robust flocculation model to estimate the floc settling velocity and the deposition rate. Single-class and sometimes two-class flocculation models are oversimplified and fail to examine complicated floc size distributions, while quadrature-based or multi-class based flocculation models may be too complicated to be coupled with large scale estuarine or ocean models. Therefore, a three-class population balance model was developed to track the sizes and number concentrations of microflocs, macroflocs and megaflocs, respectively. With the assumption of a fixed size of microflocs and megaflocs, only four tracers are needed when coupled with the open-source TELEMAC system. It enables better settling flux estimates and better addresses the occurrence and concentration of larger megaflocs. This tri-modal flocculation model was validated with two experimental data sets: (1) 1-D settling column tests with the Ems mud and (2) in-situ measurements at the WZ Buoy station on the Belgian coast. Results show that the flocculation properties of cohesive sediments can be reasonably simulated in both environments. It is also found that the number of macroflocs created, when a larger macrofloc breaks up, is a statistical mean value and may not be an integer when applying the model in the field.

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Coastal areas are urbanized and industrialized environments, affected by dredging operations, discharges of untreated municipal wastewaters, and farming. Developing countries are in continuous growth and will deal, in a close future, with the highest rate of coastal transformation, posing serious risks for the ecological and environmental value of ecosystem assets. This research aims to study the dissolved and particulate Cr, Ni, Pb and Zn values within an argentinean estuarine environment which is currently under human-induced pressures. Concentrations of all the metals under analyses showed seasonal variability of both dissolved and particulate metals. An important outcome of this study was that dissolved Cr, Pb and Zn attained maximum values and overall increased concentrations with respect to previous records from the same area. Indeed, the highest concentrations were found during the dredging operations or in association with increases in the metal levels from wastewater discharges. The results also indicated that human activities contributed the least to the dissolved Ni concentrations. The particulate fraction of Cr, Ni and Zn showed an upward trend in the concentrations, particularly during the last two sampling dates, being also positively correlated between each other. Regarding their respective environmental quality standards, many samples achieved dissolved Cr and Zn concentrations above the maximum values recommended by international guidelines. Thus, this study highlights the possibility of stressors like dredging activities and municipal wastewaters to cause increases in the water column pollution levels.

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BACKGROUND & OBJECTIVES: Aedes aegypti and Ae. albopictus are major arboviral vectors that are considered to lay eggs, and undergo preimaginal development only in fresh water collections. However, recently they have been also shown to develop in coastal brackish water habitats. The ability of the biologically variant salinity-tolerant Aedes vectors to transmit arboviral diseases is unknown. We therefore, investigated the infection of salinity-tolerant Aedes mosquitoes with dengue virus (DENV) and analysed dengue incidence and rainfall data to assess the contribution of salinity-tolerant Aedes vectors to dengue transmission in the coastal Jaffna peninsula in Sri Lanka. METHODS: Brackish and fresh water developing female Ae. aegypti and Ae. albopictus were tested for their ability to become infected with DENV through in vitro blood feeding and then transmit DENV vertically to their progeny. An immunochromatographic test for the NS1 antigen was used to detect DENV. Temporal variation in dengue incidence in relation to rainfall was analysed for the peninsula and other parts of Sri Lanka. RESULTS: Aedes aegypti and Ae. albopictus developing in brackish water, became infected with DENV through in vitro blood feeding and the infected mosquitoes were able to vertically transmit DENV to their progeny. Monsoonal rainfall was the discernible factor responsible for the seasonal increase in dengue incidence in the peninsula and elsewhere in Sri Lanka. INTERPRETATION & CONCLUSION: Fresh water Aedes vectors are main contributors to the increased dengue incidence that typically follows monsoons in the Jaffna peninsula and elsewhere in Sri Lanka. It is possible however, that brackish water-developing Aedes constitute a perennial reservoir for DENV to maintain a basal level of dengue transmission in coastal areas of the peninsula during the dry season, and this supports increased transmission when monsoonal rains expand populations of fresh water Aedes.

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The application of zinc (Zn) isotopes in bivalve tissues to identify zinc sources in estuaries was critically assessed. We determined the zinc isotope composition of mollusks (Crassostrea brasiliana and Perna perna) and suspended particulate matter (SPM) in a tropical estuary (Sepetiba Bay, Brazil) historically impacted by metallurgical activities. The zinc isotope systematics of the SPM was in line with mixing of zinc derived from fluvial material and from metallurgical activities. In contrast, source mixing alone cannot account for the isotope ratios observed in the bivalves, which are significantly lighter in the contaminated metallurgical zone (δ66ZnJMC = +0.49 ± 0.06‰, 2σ, n = 3) compared to sampling locations outside (δ66ZnJMC = +0.83 ± 0.10‰, 2σ, n = 22). This observation suggests that additional factors such as speciation, bioavailability and bioaccumulation pathways (via solution or particulate matter) influence the zinc isotope composition of bivalves.

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Humans derive many tangible and intangible benefits from coastal areas, providing essential components for social and economic development especially of less developed coastal states and island states. At the same time, growing human and environmental pressures in coastal areas have significant impacts on coastal systems, requiring urgent attention in many coastal areas globally. Sustainable development goal (SDG) 14 of the 2030 Agenda for Sustainable Development (henceforth the 2030 Agenda) aims for conservation and sustainable use of the oceans, seas, and marine resources, explicitly considering coastal areas in two of its targets (14.2 and 14.5). These promote, as we argue in this article, a strong sustainability concept by addressing protection, conservation, and management of coastal ecosystems and resources. The 2030 Agenda adopts the so-called "three-pillar-model" but does not specify how to balance the economic, social, and environmental dimensions in cases of trade-offs or conflicts. By analysing SDG 14 for the underlying sustainability concept, we derive decisive arguments for a strong sustainability concept and for the integration of constraint functions to avoid depletion of natural capital of coastal areas beyond safe minimum standards. In potential negotiations, targets 14.2 and 14.5 ought to serve as constraints to such depletion. However, such a rule-based framework has challenges and pitfalls which need to be addressed in the implementation and policy process. We discuss these for coastal areas in the context of SDG 14 and provide recommendations for coastal governance and for the process ahead.