Coastal Zone Water Research Articles

Shoreline extraction and analyzing the effect of coastal structures on shoreline changing with remote sensing and geographic information system: Case of Samsun, Turkey

Natural and man-made effects may produce dynamic changes in coastal areas. Analysis of changes in the shorelines of water bodies like seas, lakes, and wide rivers from remote sensing images is a critical issue for different applications such as monitoring coastal erosion and accretion, coastal zone management, watershed definition, flood prediction, and water resource management. This study has been done to extract and analyze the change in the shoreline around the area of the Derekoy Port and Tekkekoy Shipyard between 1995 and 2021. Geographic Information System and Remote Sensing were used for data processing, analysis, and presenting the result. An ArcGIS extension softwares, the Landsat toolbox was used to extract the shoreline using a combination of NDVI and Tasseled Cap Transformation methods, and the Digital Shoreline Analysis System was used to analyze the change of the shoreline based on the reference baseline, transects and shoreline parameters. Linear Regression Rate, End Point Rate, Shoreline Change Envelope, and Net Shoreline Movement methods have been used to analyze​ the change of the shoreline. The calculated result of the EPR and LRR methods were highly correlated with the coefficient of determination (R-square) 0.96 for Derekoy Port, and 0.93 for Tekkekoy Shipyard. In this study important changes were determined in the shoreline after Derekoy Port and Tekkekoy Shipyard were built. The results obtained from GIS and remote sensing techniques combined with digital shoreline analysis system can be beneficial for the management, planning and monitoring of the coastal zone after coastal structures have been built.

A marine plastic cloud - Global mass balance assessment of oceanic plastic pollution

To improve our understanding and management of marine plastic pollution of the ocean, a total plastic budget is needed which quantifies the sources and sinks, as well as inputs and removal of plastic per unit time. The current state of knowledge indicates that the coastal zone and ocean water column are major locations for plastic pollution, but the fate of much of this must ultimately be the deep ocean floor. We reviewed 23 journal articles that provide 280 observations of deep-sea sediment microplastic concentration across six different off-shelf environments. We calculate the following mean concentrations of microplastic particles (number) per kg of sediment: continental slope 502; submarine canyons 784; submarine fans and continental rise 714; abyssal plains 217; trenches and troughs 2782; and abyssal hills, mountains and other ocean floor 165 particles kg−1. These figures are alarming because several exceed one estimate of ‘safe’ levels of microplastic concentration for benthic marine life (540 particles kg−1). Monitoring of the concentration of plastic particles in sediments of submarine canyons, fans and continental rise environments and in trenches and troughs should be a priority to ensure efficacy of policies and actions taken to curb ocean plastic pollution at both the national and global level. We estimate 3.05 million tonnes of microplastic resides in deep ocean sediments but acknowledge the uncertainties of this figure. If correct, this figure implies that the ocean water column (which may contain as much as 90 million tonnes of microplastic) is a major, transitory sink for MP, forming a suspended, marine plastic cloud. In addition to particle concentrations, further measurements of the size and mass of microplastic in deep-sea sediments and in the water column are needed to advance development of mass balance budgets for marine plastic pollution.

The limits of coastal and marine areas in Andalusia (Spain). A socio-ecological approach for ecosystem-based management

Coastal and marine areas represent one of the most relevant spaces on a global scale to address management and conservation processes. Firstly, this is due to the interactions that characterise the area of exchange between land and sea. Secondly, it is the area where the main population settlements are located. However, there is no agreed definition of the scope of the coastal zone for management, and legal delimitations usually simplify the reality, making it impossible to develop Ecosystem Based Management in these areas. The research advances on a proposal for a conceptual and geographical delimitation of coastal areas from a socio-ecological perspective. The results show a delimitation of the coastal area based on two large geographical areas: The Coast and the Coastal Zone. The first one includes the Coastal Water, the Intertidal Area and the Shoreland. Seconly, the Coastal Zone is fundamental for understanding certain ecosystemic and social phenomena, and includes two units: Coastal Zone Water and Coastal Land. The proposed socio-ecological limits do not always coincide with the legal limits, which is why this article analyses in depth, for the case of Andalusia (Spain), the state and regional legislation on coastal matters. With all this, ideas are proposed on which to introduce socio-ecological delimitation into the legal limits and thus advance towards Ecosystem-Based Management in coastal and marine areas.

Airborne Radiometry for Calibration, Validation, and Research in Oceanic, Coastal, and Inland Waters

Present-day ocean color satellite sensors, which principally provide reliable data on chlorophyll, sediments, and colored dissolved organic material in the open ocean, are not well suited for coastal and inland water studies for a variety of reasons, including coarse spatial and spectral resolution plus challenges with atmospheric correction. National Aeronautics and Space Administration (NASA) airborne mission concepts tested in 2011, 2013, 2017, and 2018 over Monterey Bay, CA, and nearby inland waters have demonstrated the feasibility of improving airborne monitoring and research activities in case-1 and case-2 aquatic ecosystems through the combined use of state-of-the-art above- and in-water measurement capabilities. These competencies have evolved through time to produce a sensor-web approach: imaging spectrometer, microradiometers, and a sun photometer (airborne) with their analogous algorithms, and with corresponding in-water radiometers and ground-based sun photometry. The NASA airborne instrument suite and mission concept demonstrations, leveraging high-quality above- and in-water data, significantly improves the fidelity as well as the spatial and spectral resolution of observations for studying and monitoring water quality in oceanic, coastal, and inland water ecosystems. The goal of this series of projects was to develop and fly a portable airborne sensor suite for NASA science missions focusing on a gradient of water types from oligotrophic to turbid waters addressing the challenges of an optically complex coastal ocean zone and inland waters. The airborne radiometry in this range of aquatic conditions and sites has supported improved results of studies of water quality and biogeochemistry and provides capabilities for research areas such as ocean productivity and biogeochemistry; aquatic impacts of coastal landscape alteration; coastal, estuarine, and inland waters ecosystem productivity; atmospheric correction; and regional climate variability.

Interconnection of bacterial and phytoplanktonic communities with hydrochemical parameters from ice and under-ice water in coastal zone of Lake Baikal

We analysed the relationship between the chemical complex (concentration of dissolved ions, nutrients, pH) and biological parameters (primary production, biomass of phytoplankton, abundance and activity of bacterial communities) at estuaries of rivers and coastal waters of Southern Baikal during the under-ice period. Correlation network analysis revealed CO2 to be the main limiting factor for the development of algae and microbial communities in the coastal zone of Lake Baikal. This study indicates that primarily reverse synthesis of bicarbonate and carbonate ions associated with the development of phytoplankton and accumulation of dissolved CO2 during photosynthesis regulates pH in the Baikal water. We did not detect the anthropogenic factors that influence the change in pH and acidification. Near the Listvyanka settlement (Lake Baikal, Listvennichnaya Bay), there was a great number of organotrophs and thermotolerant bacteria with low bacterioplankton activity and high concentration of organic carbon. This evidences eutrophication due to the influx of organic matter having an anthropogenic source. Nutrients produced during the bacterial destruction of this matter may explain the changes in bottom phytocenoses of Listvennichnaya Bay.

Biogeography of epibenthic assemblages in the central Beaufort Sea

Benthic communities change drastically in both biomass and community structure with increasing water depth on a global scale, attributed to a combination of food supply, environmental drivers, as well as physiological and competitive capacities. In the Arctic, benthic biogeographic patterns are additionally thought to be a result of the region’s glaciation history. Here, we investigate gross epibenthic biomass and assemblage structure turnover with water mass from coastal to bathyal depths from 136 beam trawl samples collected in the Beaufort Sea. We test whether Pacific Boreal Arctic species have their core distribution in shelf water masses while Atlantic Boreal Arctic species have wider depth ranges. Gross biomass estimates differed statistically among water masses, with high values mostly under the influences of the Polar Mixed Layer and Arctic Halocline (outer shelf and upper slope, respectively). Stations in the Coastal Zone and Canada Basin Deep Water had the lowest biomass. Epibenthic assemblages also differed significantly among water masses, with high taxon richness in shelf water masses that decreased considerably with depth. Biomass of benthic taxa with Pacific Boreal Arctic affinity was essentially limited to the shelf, while Atlantic Boreal Arctic taxa occurred across a broad depth range, though their biomass increased in deeper water masses for mollusks and echinoderms, but not for decapods/isopods. Our results confirm earlier evidence of a strong Atlantic-Arctic deep-water connectivity reaching into the Pacific Arctic region and suggest new arrivals of species from the boreal Pacific are likely to settle on Pacific Arctic shelves, but are unlikely to invade continental slope and basin waters in the foreseeable future.

Modelling of water quality management in the sea coastal zone

Coastal territories are one of the most dynamically developing regions. Sea resorts focused on recreational and tourist activities are developing especially quickly. For such territories, their ecological status, especially the quality of coastal zone water resources, plays an important role in their sustainable development. Analysis of physical factors of water exchange and assessment of water resources quality of the coastal zone of the sea, including in closed and semi-enclosed water areas, was carried out. It has been shown that water exchange is the most important factor in the management of the quality of marine waters of partially enclosed coastal areas. 0-dimensional and system-dynamic models were used to analyze water exchange in the coastal zone of the sea. Results of studies made it possible to assess the circulation of coastal marine waters and the change in certain indicators of the quality of water resources, including in the presence of various coastal protection construction.

A 3D-hydrodynamic model for predicting the environmental fate of chemical pollutants in Xiamen Bay, southeast China

Simulation model is very essential for predicting the environmental fate and the potential environmental consequences of chemical pollutants including those from accidental chemical spills. However very few of such simulation model is seen related to Chinese costal water body. As the first step toward our final goal to develop a simulation model for the prediction and the risk assessment of chemical pollutants in Chinese coastal water, this study developed a three-dimensional (3D) hydrodynamic model of Xiamen Bay (XMB). This hydrodynamic model was externally derived by meteorological data, river discharge and boundary conditions of XMB. We used the model to calculate the physical factors, especially water temperature, salinity and flow field, from June to September 2016 in XMB. The results demonstrated a good match between observations and simulations, which underscores the feasibility of this model in predicting the spatial-temporal concentration of chemical pollutants in the coastal water of XMB. Longitudinal salinity distributions and the mixing profile of river-sea interactions are discussed, including the obvious gradation of salinity from the river towards sea sites shown by the model. We further assumed that 1000 kg and 1000 mg/L of a virtual chemical pollutant leaked out from Jiulong River (JR) estuary (point source) and whole XMB (non-point source), respectively. The model illustrates that it takes three months for XMB to become purified when point source pollution occurs in the estuary, while half a year to be required in the case of non-point source pollution across the entire bay. Moreover, the model indicated that pollutants can easily accumulate in the western coastal zone and narrow waters like Maluan Bay, which can guide environmental protection strategies.

Element Composition and Biogeochemical Functions of Algae Ulothrix Zonata (F. Weber et Mohr) Kützing in the Coastal Zone of the Southern Baikal

ICP-MS method was used to study the element composition of green algae Ulothrix zonata (F. Weber et Mohr) Kutzing, sampled in the coastal zone of the Southern Baikal. Dominating in Ulothrix composition are S, Ca, P, Mg and microelements Fe, Al, Ti, Mn, Sr, Ba, Cu, Zn, La, Ce, As, Br, and Pb. The concentrations of all analyzed elements in alga thallomes is greater than the respective concentrations in coastal zone water. The dry mass of U. zonata accumulates more P, As, S, I, Br, Ni, Cd, Ca, and Mg than the stone substrate does. The effect of U. zonata on the formation of element composition of water medium in the coastal zone is demonstrated.

Estimating Currents From Argo Trajectories in the Bothnian Sea, Baltic Sea

Argo floats have been used in the environmental monitoring of the Bothnian Sea, a sub-basin of the Baltic Sea, for five years as part of the Finnish Euro-Argo programme. The Bothnian Sea is considered to be an environmentally healthy part of the Baltic Sea because the deep waters of the basin are well-ventilated by inflowing oxygen-rich saltier and heavier surface layer waters of the Baltic Sea proper. Thus the deep water flow is of interest in the Bothnian Sea. In this study, we used Argo float data from six different long-term missions, from 111 to 512 days, to analyze the deep-water flow in the Bothnian Sea where no continuous monitoring of currents exist. We estimated mainly the flow below the expected halocline from the paths of the floats. We analyzed the movements statistically and estimated the error caused by the surface drift of the floats during their stay at the surface by using 3D hydrodynamic model results as reference data. Our results show a cyclonic resultant current in the deep trench of the Bothnian Sea. There seemed to be very little exchange between coastal zone and open-sea waters in deeper layers. The drifting speed of the floats in the deep layers of Bothnian Sea generally was around 2 cm/s but instantaneous speeds of tens of centimeters up to 30 cm/s in the middle-layer (50 dbars) were observed. In the Bothnian Sea deep, the deep trench on the Finnish side of the Bothnian Sea, the vast majority of the observations showed deep currents from south to north, with the same average speed of around 2 cm/s but the instantaneous maximum was smaller at 13 cm/s. Our study indicates that the routine Argo float observations can be used to get information on the deep currents in the basin in addition to traditional hydrographic observations. This helps in improving our understanding of the oxygen dynamics of the bottom layers of the Bothnian Sea, and the living conditions of the benthic phyto- and zooplankton communities there.

Policy Options for Coastal Protection: Integrating Inland Water Management with Coastal Management for Greater Community Resilience

Coastal cliff collapse is a problem faced along many shorelines the world over, especially as cliffs tend to be impacted by global climate change. Problems of cliff collapse can benefit from interdisciplinary policy responses that synthesize principles of integrated watershed management, integrated coastal zone management and water sensitive urban design. This exploratory, largely empirical research, looks at how local and national policies address coastal cliff collapse along Israel's Mediterranean seashore, in a way that highlights impediments and opportunities for integrated planning. Findings emphasize the importance of addressing urban runoff to prevent coastal cliff collapse using practices originating based on the three paradigms. Conclusions provide insights about policies that could improve the resilience of coastal communities suffering from coastal cliff collapse in the era of climate change. Particularly, greater cross-scale (regional and national) efforts are needed to coordinate proper drainage of the watershed which along coastal cliffs involves integrating principles of watershed management, coastal management and urban design practices. These should be aimed at implementing practices that reduce phenomena that lead to cliff destabilization, such as insuring runoff diversion and building setbacks. The case study research leads to recommendations for policy mechanisms that provide opportunities to implement such practices.

Twenty-first century climate change and submerged aquatic vegetation in a temperate estuary: the case of Chesapeake Bay

ABSTRACTIntroduction: The Chesapeake Bay was once renowned for expansive meadows of submerged aquatic vegetation (SAV). However, only 10% of the original meadows survive. Future restoration efforts will be complicated by accelerating climate change, including physiological stressors such as a predicted mean temperature increase of 2–6°C and a 50–160% increase in CO2 concentrations.Outcomes: As the Chesapeake Bay begins to exhibit characteristics of a subtropical estuary, summer heat waves will become more frequent and severe. Warming alone would eventually eliminate eelgrass (Zostera marina) from the region. It will favor native heat-tolerant species such as widgeon grass (Ruppia maritima) while facilitating colonization by non-native seagrasses (e.g., Halodule spp.). Intensifying human activity will also fuel coastal zone acidification and the resulting high CO2/low pH conditions may benefit SAV via a “CO2 fertilization effect.”Discussion: Acidification is known to offset the effects of thermal stress and may have similar effects in estuaries, assuming water clarity is sufficient to support CO2-stimulated photosynthesis and plants are not overgrown by epiphytes. However, coastal zone acidification is variable, driven mostly by local biological processes that may or may not always counterbalance the effects of regional warming. This precarious equipoise between two forces – thermal stress and acidification – will be critically important because it may ultimately determine the fate of cool-water plants such as Zostera marina in the Chesapeake Bay.Conclusion: The combined impacts of warming, coastal zone acidification, water clarity, and overgrowth of competing algae will determine the fate of SAV communities in rapidly changing temperate estuaries.

Impacts of a high-discharge submarine sewage outfall on water quality in the coastal zone of Salvador (Bahia, Brazil)

Carbon and nitrogen stable isotopic signatures of suspended particulate organic matter and seawater biological oxygen demand (BOD) were measured along a coastal transect during summer 2015 to investigate pollution impacts of a high-discharge submarine sewage outfall close to Salvador, Brazil. Impacts of untreated sewage discharge were evident at the outfall site by depleted δ13Corg and δ15N signatures and 4-fold increased BOD rates. Pollution effects of a sewage plume were detectable for more than 6km downstream from the outfall site, as seasonal wind- and tide-driven shelf hydrodynamics facilitated its advective transport into near-shore waters. There, sewage pollution was detectable at recreational beaches by depleted stable isotope signatures and elevated BOD rates at high tides, suggesting high bacterial activity and increased infection risk by human pathogens. These findings indicate the urgent necessity for appropriate wastewater treatment in Salvador to achieve acceptable standards for released effluents and coastal zone water quality.

VARIABILITY OF CARAPACE WIDTH SIZE AND ABUNDANCE OF BLUE SWIMMING CRABS (Portunus pelagicus Linnaeus) IN PATI WATERS

<p><em>Fishing effort enhancement would put pressure on blue swimming crab resources and its ecosystem. The objective of this study was to determine the spatial distribution based on the size of the carapace width (CW), abundance, temperature, salinity, depth, and fishing intensity in Pati waters which was divided into two zones (zones 1=nearshore, zone 2=offshore). The result showed that the average of carapace width in zone 1 to zone 2 was significantly different (p <0.05), as well as between males and females. Average number of individual (abundance) was significantly different according to fishing areas and sex (p <0.05). The average of water temperature in zone 1 was higher than in zone 2, salinity in zone 1 was smaller than in zone 2, and the water depth in zone 1 was shallower than in zone 2. The higher the crab catch intensity leaded to the smaller the abundance and size of carapace width. Alternative management strategies were proposed such as to divert fishing grounds from coastal waters to offshore during low productivity season, to uphold rules on minimum legal size for catching (Lm = 107 mm), to release of berried females catch, and to reduce accretion rate of gear and fishing fleet mainly in the coastal zone waters.</em></p><p><em><strong><em>Keywords: </em></strong><em>blue swimming crab, carapace widht (CW), abundance, intensity of fishing</em></em></p>

Influence of salinity on COD measurements in coastal water management

Chemical oxygen demand (COD) is an important parameter in water quality assessment. COD values by different determination methods were investigated in coastal rivers. The results show that there is no clear relationship between CODCr and CODMn in coastal areas. CODCr does not reflect the degree of pollution of coastal waters. As salinity increased, CODCr and acidic CODMn increased significantly, but there was little/no change observed for alkaline CODMn. Coastal zone water quality standards should be proposed to solve connection problems between marine quality standard and surface water quality standard.

Evolution of a physical and biological front from upwelling to relaxation

Fronts influence the structure and function of coastal marine ecosystems. Due to the complexity and dynamic nature of coastal environments and the small scales of frontal gradient zones, frontal research is difficult. To advance this challenging research we developed a method enabling an autonomous underwater vehicle (AUV) to detect and track fronts, thereby providing high-resolution observations in the moving reference frame of the front itself. This novel method was applied to studying the evolution of a frontal zone in the coastal upwelling environment of Monterey Bay, California, through a period of variability in upwelling intensity. Through 23 frontal crossings in four days, the AUV detected the front using real-time analysis of vertical thermal stratification to identify water types and the front between them, and the vehicle tracked the front as it moved more than 10 km offshore. The physical front coincided with a biological front between strongly stratified phytoplankton-enriched water inshore of the front, and weakly stratified phytoplankton-poor water offshore of the front. While stratification remained a consistent identifier, conditions on both sides of the front changed rapidly as regional circulation responded to relaxation of upwelling winds. The offshore water type transitioned from relatively cold and saline upwelled water to relatively warm and fresh coastal transition zone water. The inshore water type exhibited an order of magnitude increase in chlorophyll concentrations and an associated increase in oxygen and decrease in nitrate. It also warmed and freshened near the front, consistent with the cross-frontal exchange that was detected in the high-resolution AUV data. AUV-observed cross-frontal exchanges beneath the surface manifestation of the front emphasize the importance of AUV synoptic water column surveys in the frontal zone.

Diversity and catching size of grouper fish (Serranidae) in coastal zone waters of Khanh Hoa province

Diversity and catching size of grouper fish (Serranidae) in coastal zone waters of Khanh Hoa province

Biosurfactant-producing Rhodococcus ruber TD2 isolated from oil poluted water in vung tau coastal zone

Biosurfactant-producing Rhodococcus ruber TD2 isolated from oil poluted water in vung tau coastal zone

Mangrove sedimentary characteristics and implications for crab Ucides cordatus (Crustacea, Decapoda, Ucididae) distribution in an estuarine area of the Amazonian region

At the coastal zone sediments, water and organisms interact intensely. At equatorial tidal-dominated coast mangroves are abundant. These areas are well-known for their ecological importance. Considering the mangroves of Atlantic South America, the mangrove crab, Ucides cordatus has ecological and economic prominence. High densities of this crab are found on the Amazon coast. This study investigates the sediment distribution of the Bragança mangrove area (Amazon coast, Brazil) and its correlations with vegetation and mangrove crab distribution. Sediments of 47 sites, as well as crabs from sites with different sediment and vegetation, were sampled. Results show that surface sediment of the area is mainly composed by silt (59%), with 21% sand and 20% clay. Variations in sorting and skewness are the product of local variations in clay and sand content. The vegetation type was significantly correlated to mangrove crab characteristics, abundance and weight/size. Sediment characteristics are also substantially different according to the vegetation type. Areas where Avicennia germinans prevails have more sand and clay than areas of Rizophora mangle, in which silt is dominant and crabs were significantly heavier. The present results have showed that the distribution of sediments, crabs and vegetation at mangrove areas are strongly correlated. Thus, they should be studied in conjunction.

Coastal zone water quality: calibration of a water-turbidity equation for MODIS data

A nephelometric turbidity algorithm has been specifically calibrated for coastal waters in Sicily. To this purpose, intensive field campaigns were performed in July, August and September 2008. Measurements were collected in situ in three different gulfs. Statistical analysis suggests that field data should be spatially grouped but temporally separated; hence, new calibration parameters have been proposed.Turbidity retrieved by applying the algorithm using literature coefficients and the ones calibrated in situ are shown and compared. The comparison demonstrated that a specific calibration was necessary for quantitatively monitoring turbidity in Sicilian gulfs.