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Martdianto, R.; Muin, M.; Kusuma, S.B.; Muslim, A.B., and Alam, H.N., 2023. BOD-salinity simulation in the Sunter River Tanjung Priok port with a non-orthogonal model application. In: Lee, J.L.; Lee, H.; Min, B.I.; Chang, J.-I.; Cho, G.T.; Yoon, J.-S., and Lee, J. (eds.), Multidisciplinary Approaches to Coastal and Marine Management. Journal of Coastal Research, Special Issue No. 116, pp. 76-80. Charlotte (North Carolina), ISSN 0749-0208. Tanjung Priok port is the biggest port in Indonesia, located in the Capital City of Jakarta, equipped with two sides of a breakwater that protects the port from the direct impact of the sea. The Sunter river flow to Tanjung Priok port delivers high domestic waste as an influence of urban activities. The high content of BOD values along the Sunter river to Tanjung Priok increases the source of water pollution that needs to control correctly. Tanjung Priok also has pollution sources consisting of solid domestic waste, domestic liquid waste, and oil sludge. The Sunter river streamflow in the Jakarta drainage system is divided by Kanal Banjir Timur (KBT), changing flow rate, and water quality pattern. The study area is the Sunter river's main channel, which has a 17 km length and includes Duren Sawit, Pulo Gadung, Kelapa Gading, Plumpang, Rawa Badak, and Tanjung Priok. To describe the complexity of a river's geometric flow to an estuary along the Sunter river to Tanjung Priok, the concept of a curvilinear Non-Orthogonal model is used, which is careful in composing the river morphology shape, river-channel branching, dimension, and elevation of the river to the estuary. Efforts to improve water quality along the Sunter river by increasing saltwater's effect by carrying out a Density-Induced Current (DIC) and dredging configuration. Dredging at the mouths of rivers by considering the influence of DIC involves water currents, river flow, wind stress, and tides. The study presents several simulation scenarios using MuQual3D to assess water quality problems in the Sunter river by increasing salinity through river dredging. [ABSTRACT FROM AUTHOR]

ABSTRACT Mascarenhas, A.C.C.; Correa, A.W.R.; Carneiro, A.C.; Costa, M.S.; Rollnic, M., and Medeiros, C., 2018. Seasonal Exchanges of Salt and Suspended Particulates between the Sol Bay and the Pará River, Amazonian Coast. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 111–115. Coconut Creek (Florida), ISSN 0749-0208. Salt and suspended particulate matter (SPM) exchange between the Sol Bay and the Pará River and their tidal/seasonal variability was investigated along the interface cross-section (1°4′30.37″S 48°19′37.48″W), over spring tidal cycles, during the wet (Apr/2015) and dry (Oct/2015) seasons. Advective transport of salt and SPM was analyzed to evaluate trends and contributions of involved mechanism. Overall, salinity was low (S<2) during dry and absent during the wet season. Mean SPM concentrations where higher at flood tides during both seasons. Higher flow velocities were 1.29 m.s−1 (ebb/wet) and 1.17 m.s−1 (flood/dry). During the dry season net salt transport was 8.10 kg.s−1 seawards mainly due to a baywards Stokes drift transport (−193.7 kg.s−1) against a seawards transport by the river discharge, tidal correlation and turbulent shear components (+179.0; +11.98; +7.72 kg.s−1). However, SPM was stored into Sol Bay at a rate of 2.06 kg.s−1 (90 ton per tidal cycle), as result of the baywards transport by the Stokes drift+river discharge (−3.14; −0.82 kg.s−1) in opposition to the seawards transport due to gravitational circulation+tidal correlation components (+1.69; +0.48 kg.s−1). During the wet season the river discharge (29.8 kg.s−1) fluxes out SPM from Sol Bay while the Stokes drift (3.19 kg.s−1) and the turbulent shear (0.65 kg.s−1) components tends to move SPM back into the bay with a net exportation of SPM to the Pará River of 26 kg.s−1 (129.8 ton per tidal cycle). In conclusion, matter exchange between the Sol Bay and the Pará River is mainly governed by the river discharge and Stokes drift flow components. The relative contributions by the gravitation circulation, tidal correlation and turbulent shear tend to increase under low river discharge. A small salt exportation (+8.10 kg.s−1) during the dry season [ABSTRACT FROM AUTHOR]

ABSTRACT Kim, N.-H.; Hwang, J.H., and Kim, D.H., 2018. Evaluation of Mixing and Stratification in an Estuary of Korea. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 96–100. Coconut Creek (Florida), ISSN 0749-0208. In the estuary, flow structures depend on the relative contributions of the tidal current and the released freshwater, which determine the mixing and the stratification. To understand how artificially discharged freshwater affect the flow structure in an estuary of Korea, flow velocities, temperature, and salinity were measured in the field. During the field campaign, discharged freshwater cyclically forms the stratified layers during ebb tide and relatively well mixed water column during flood tide as in the conventional estuarine process. The gradient Richardson number evaluated such cyclic patterns quantitatively with the field measurement data, which were sampled following the tidal cycle and after the release of freshwater. In the early stage of the freshwater discharge, stratification dominates due to the large density difference, which overcomes the mixing by shear at the interface. As time goes on, the momentum of the released flow weakened and tidal modulation becomes significant and the discharged freshwater advected back and forth along the tidal currents. Different from the conventional mixing during flood, the stratification breaks down not by vertical mixing caused by the shear generated turbulence but by the vertical advection in the front of the gate. [ABSTRACT FROM AUTHOR]

ABSTRACT Costa, M.S.; Rocha, A.S.; Santos, A.S., and Rolnic, M., 2018. Influence of tide on salt entrapment in the River Mojuim Estuary. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 81–86. Coconut Creek (Florida), ISSN 0749-0208. The aim of this study is to check whether there is salt entrapment in an estuary in the Amazon eastern coast. This study case was conducted in a section of the lower Mojuim River estuary. Tide, current, and water salinity were measured for 25 h during wet and dry seasons, 2014. Tide and salinity levels were recorded at fixed stations for 55 consecutive days during each season. Advective, diffusive, and dispersive salt transport and the Stratification/Circulation diagram were calculated. The Mojuim River estuary has a macrotidal, semidiurnal regime, with tide height of 4.9 m during spring tide and 3.2 m during neap tide. Maximum current intensities during wet season are 1.6 m.s−1 in flood tide and 1.9 m.s−1 in ebb tide, whereas during dry season, they are 1.2 m.s−1 in ebb tide and 1.6 m.s−1 in flood tide. Mean salinity increased from 7.3 g.kg−1 (±2.82) during wet season to 21.2 g.kg−1 (±3.62) during dry season. Advective salt transport was 736.4 kg.s−1 during wet season and 72.1 kg.s−1 during dry season, up-estuary and down-estuary, respectively. River discharge and Stokes transport are the predominant components of advective salt transport. It allows salt entrapment in the estuary during extreme tides, which might be retained in the floodplains. As the Mojuim river estuary is shallow (mean depth 4.5 m), the water column varies according to the fluvial component and to tides. Thus, the intensity of the fluvial component and tides during wet season promotes eddy mixture. During dry season, a decreased fluvial component due to low rainfall increases saline intrusion and causes the water column to be slightly stratified. The Mojuim river estuary was classified as well mixed during wet season and slightly mixed during dry season, according to the Stratification/Circulation diagram. [ABSTRACT FROM AUTHOR]

ABSTRACT Valentim, M.M.; Monteiro, S.M., and Rollnic, M., 2018. The influence of seasonality on haline zones in an Amazonian estuary. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 76–80. Coconut Creek (Florida), ISSN 0749-0208. This study relates salinity fluctuations throughout Mojuim estuary, dominated by macrotides and situated in the humid tropical region between the Pará River mouth and the Atlantic ocean (−0.72° and −48.00°), Northeastern Pará, Brazil. Water salinity in situ were measured, on the surface and at the bottom, with a multiparameter probe (Horiba U-50) for six months, corresponding to the intermediate season (July and August, 2016), dry season (November and December, 2016), and rainy season (January and February, 2017) during spring tide. Sampling stations comprehended 50 km throughout the estuary and were divided in five 10-km sectors. The sectors were classified according to the Venice System. Significant variations salinity (p>0.5) in water column were not observed, as it is a well-mixed estuary. During rainy season, were observed the lowest mean salinity (8.5±0.8 PSU), which increased to 15.99±0.37 PSU during the intermediate season, and to 22.38±0.61 PSU during dry season. Saline intrusion reached sector 5 (50 km upstream of the mouth) during dry season and was restricted to sector 3 (30 km) during rainy season. The latter showed the highest variation in haline zones in all seasons, and they varied from oligohaline during rainy season, to mesohaline during intermediate season, and polyhaline during dry season. During rainy and intermediate seasons, river domain limits tidal progression, and it is why sector 5 shows no haline variations, remaining as a freshwater zone, as opposed to dry season, when this sector shows a oligohaline zone, due to the higher tide reach and to the higher dispersion of salts in the estuary. These haline limits might vary interannually, which indicates the influence of climatological anomalies on estuary dynamics over the last years. [ABSTRACT FROM AUTHOR]

ABSTRACT Valentim, S.S.; Menezes, M.O.B., and Teixeira, C.E.P., 2018. Seasonally hypersaline estuaries in semiarid climate regions: an Example from the Northeast Brazil. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 6–10. Coconut Creek (Florida), ISSN 0749-0208. The Coreaú river estuary is located in Ceará state, Northeast of Brazil and it is a shallow system, dominated by meso tides and barred about 35 km upstream from its mouth. Generally, hypersaline estuaries are naturally found in arid and semi-arid regions of Brazil, but the blockage the natural flow of rivers by dam interference can also increase hypersaline conditions and residence time in these estuaries. This study examines the importance of water balance and dam interference to the circulation of the Coreaú river estuary, using observed data and Delt3D numerical simulations. Five discharge scenarios (with values from 0 to 300 m3s−1) were used in the Delft3D simulations to calculate the residence and flushing time in the estuary. Based on salinity data collected during two years the estuary was characterized as a hypersaline and well mixed system during the dry period (August to December) and a positive estuary during the wet season (January to June). The observed salinity along the estuary ranged from 37 g/kg to 44 g/kg in October, 2012 and from 37g/kg to 13g/kg in May, 2013, respectively near the mouth and 20 km upstream. Regardless of the discharge conditions and the atmospheric water balance, the estuary acquires hypersaline conditions during the dry season. Tidal circulation under all discharge conditions dominates the residence time in the first 10 km of the estuary. Water and materials from the upper region of the estuary depends on the river discharge to be transported to the shelf. Under all discharge conditions lower than 300 m3 s−1 the flushing time of the upper estuary is larger than 60 days. These fact associated with the high values of evaporation during the dry season explains the hypersalinization of the Coreaú estuary. [ABSTRACT FROM AUTHOR]

Azhikodan, G. and Yokoyama, K., 2015. Temporal and spatial variation of mixing and movement of suspended sediment in the macrotidal Chikugo River estuary. The effect of mixing on the movement of the estuarine turbidity maximum (ETM) was examined in the highly turbid Chikugo River estuary, Japan, in consideration of four significant issues: semidiurnal and semilunar tidal variations, spatial distribution, and synchronism of data acquisition. Vertical profiles of salinity and turbidity were measured for 2 weeks at 1 km intervals from the river mouth (0 km) to 17 km upstream, with a short duration for every cruise. Spring-neap transition and the spatial variation of mixing, and suspended sediment concentration (SSC) was found during the semilunar tidal cycle. The estuary gradually changed from a vertically well-mixed condition during spring tide to a stratified condition during the neap tide via a partially mixed condition during the intermediate half tides. The relationship between the flow ratio and the SSC showed that ETM growth was dominated by both tidal forcing and freshwater flow. SSC was high when the salinity was 0.5 practical salinity units (psu) in the upper estuary and 10 psu in the lower estuary. For the same mixing strength (MS), SSC in the lower estuary was greater than that in the upper estuary. Based on flow ratio, salinity, and MS, the occurrence of the ETM and its development at the macrotidal estuary was a consequence of three processes: bed-sediment erosion by seawater in the lower estuary, sediment transport in the estuarine channel by the tidal current and freshwater flow, and sediment accumulation at the salinity front in the upper estuary. [ABSTRACT FROM AUTHOR]

This work presents empirical data from several databases. Empirical data ultimately form the basis for most ecological/environmental studies, and this work uses what may be the most comprehensive data set ever compiled concerning relationships between chlorophyll-a concentrations, nitrogen, phosphorus, and salinity, since the data in this study concerns about 500 lakes and coastal areas. The focus has been on how variations between systems in median summer values of chlorophyll-a concentrations (Chl) depend on variations in total nitrogen, total phosphorus, and salinity. The salinities range from 0 to 275 PSS78 in hypersaline systems; the median salinity is 12.5. The range in nutrients is from ultraoligotrophic (totalP, or TP, is less than 1 μ g/L) to hypertrophic systems (TP is greater than 1000 μ g/L). The chlorophyll values vary from 0.12 to 60 μ g/L. Results showed that there is a minimum in the Chl/TP ratio in the salinity range between 2 and 5, followed by an increase up to a salinity range of 10-15, and then a continuous reduction in the Chl/TP ratio until a minimum value of about 0.012 is reached in hypersaline systems. We have also identified a threshold value for the salinity. In systems dominated by freshwater influences, the ratio of Chl to total nitrogen, or TN, increases steadily from about 0.008 in lakes to 0.02 when the salinity is 10. At higher salinities than 10, the Chl/TN ratio decreases in a nonlinear fashion. We have also presented several empirical models to predict chlorophyll concentrations from levels of TP, TN, and salinity. The model predicting Chl from TP and salinity is generally the best one. The next best model according to the criteria (r2 value, median error, and standard deviation for the error) is the model using TN and salinity. Models not including salinity predict chlorophyll less well. [ABSTRACT FROM AUTHOR]

The three-dimensional circulation, salinity distribution, and overall transport pattern were simulated in the Pearl River Estuary, China, using a modified version of the Princeton Ocean Model (POM). The circulation in the estuary is mainly driven by tide, wind, and river runoff in a complex manner, where the relative importance of the different forcing factors varies over the year. Field data on currents from several locations in the estuary taken at different elevations through the water column were employed to validate the model together with measurements of the salinity distribution in the surface layer. Also, satellite images were utilized to qualitatively confirm the simulated overall transport pattern. Comparisons between measurements and calculations showed that the POM yielded satisfactory predictions without any particular calibration. However, for some events the coastal current outside the estuary induced by the large-scale circulation in the South China Sea affected the flow in the estuary, making it necessary to employ a more sophisticated boundary condition on the ocean side than what was initially implemented. The long-term objective of the numerical modeling of the flow and material transport in the Pearl River Estuary is to utilize the validated model for forecasting the circulation and water quality in the estuary in a comprehensive system where in-situ measurements and remote sensing are the other main components. [ABSTRACT FROM AUTHOR]

A port complex was implanted in the coast region of Suape, PE-Brasil, in 1979–80, which altered the geomorphological and hydrodynamic conditions of the area, mainly in the estuary of the Ipojuca River. Water samples were collected from the surface and the deep layer to determine the salinity, pH, dissolved oxygen, transparency, and temperature from three fixed stations in the estuary of the Ipojuca River during the summer and winter before (1978) and after (1986–87) the port's construction, in order to evaluate the effects of the port-induced changes. The data were subjected to a principal component analysis and to individual t tests. The first principal component, the axis of maximum information, alone explained 50% of the total variance, being associated with the generalized increase of the chemical parameters after the port's construction, mainly the salinity. Despite the fact that the results of the t tests presented significant differences only for the dissolved oxygen, pH, and temperature, the increased salinity produced the greatest ecological effects in the estuary. The water flow of the Ipojuca River was diverted toward the ocean, decreasing the river-flow velocity at the mouth. This decrease in flow caused a sedimentation in the area, a decrease in the circulation and depth, and a transformation of the mouth of the river into a coastal lagoon with an increase in evaporation and salinity. A delay of more than 2 hours was observed in the dynamic tide in relation to the normal 6-hour cycles. Despite an increase in the concentration of dissolved oxygen and transparency values, effects that theoretically improve environmental conditions, a morphological transformation occurred that caused drastic changes in the estuary's circulation and in the tidal currents. [ABSTRACT FROM AUTHOR]