• Proceedings of the KSRS Conference
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• v.1
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• pp.455-458
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• 2006

Stretching on the coastline of 70 km, the Tam Giang - Cau Hai Lagoon plays a very important role for the coastal ecology and socio-economic development of Hue region where was Vietnam's Ancient Kingdom Capital and recognized as a World's Cultural Heritage. Recently, coastal hazard in the lagoon have occurred seriously such as inlet movement and fill up, coastal erosion, flood and inundation, etc. These hazards have impacted on lagoon environment, resources, ecosystems, socio-economic and sustainable development of this coastal area. This paper present a case study using remote sensing data in combination with ground survey for monitoring the coastal hazards in Tam Giang - Cau Hai lagoon in recent decades. Analysis results find that during its natural evolution, the lagoon has been being in three situations of only one, two and three inlets. When inlets opened or displaced, coastal erosion have occurred seriously toward new balance condition. Flood and inundation occurs every rainy season in lowland plain around lagoon. The historical flood happened in early of November 1999 with six days long, created very terrible damages for Thua Thien Hue province. Remote sensing data with capability of regular update, large area coverage is effective provide real-time and continuous information for coastal hazards monitoring.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.247-247
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• 2023

Coastal lagoons play a crucial role in water exchange, water quality, and biodiversity. It is essential to monitor and understand the dynamics of hydrogeochemistry in lagoon water and its groundwater to preserve and sustainably manage the groundwater-dependent ecosystems like coastal lagoons. This study investigated the spatial and temporal hydrogeochemical characteristics of coastal lagoon (Songjiho) and groundwater on the east coast of Korea. The concentrations of major ions, water isotopes, and nutrients (nitrogen and dissolved organic carbon) in lagoon water and groundwater were periodically monitored for one year. The study revealed that major ions and total dissolved solids (TDS) concentration were higher at deeper depths of aquifers and closer to the coastal area. The hydrogeochemical characteristics of coastal lagoon and groundwater chemistry were classified into two types, Ca-Mg-HCO₃ and Na-Cl, based on their spatial location from inland to coastal area. Moreover, the hydrogeochemical characteristics of coastal lagoons and groundwater varied significantly depending on the season. During the wet season, the increased precipitation and evaporation lead to changes in water chemistry. As a result, the total organic carbon (TOC) of coastal lagoons increases during this season, likely due to increased runoff by rainfall whereas the variation of chemical compositions in the lagoon and groundwater were not significant because there is reduced precipitation, resulting in stable water levels and during the dry season. The study emphasizes the impact of spatial distribution and seasonal changes in precipitation, evaporation, and river discharge on the hydrogeochemical characteristics of the coastal aquifer and lagoon system. Understanding these impacts is crucial for managing and protecting coastal lagoons and groundwater resources.

• Fisheries and Aquatic Sciences
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• v.26 no.4
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• pp.294-303
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• 2023

Beside that the fish species and their sub-populations are highly important as a keystone species in the coastal and marine ecosystem, there are very few studies on their presence, distribution and temporal variations within and around the lagoon ecosystems in Albania. This paper provides an updated review on the life cycle, fishery, exploitation state and management of the main species that are subject of commercial fishing in the Karavasta lagoon, southeastern Adriatic coast of Albania. Due to the fact that lagoons represent a continuum between continental and marine aquatic ecosystems they play a crucial role in species life cycles. Further on in the circumstances of rapid utilizations and environmental changes, anomalies in salinity and temperatures, accelerated anthropogenic influences their rate of vulnerability is highly increased. Following the requirements of the Water Framework Directive, transitional water, coastal lagoons and estuaries there is a need for urgent monitoring and management approaches. The commercial species include: European eel (Anguilla anguilla), species of Family Mugilidae (Mugil cephalus, Liza ramada, Liza salienes and Chelon labrosus), Seabream (Sparus aurata), Seabass (Dincentrarchus labrax), etc. Fish productivity is oscillating from maximum value of 61.95 kg/ha is recorded in period of 1975-80 and lower value of 31 kg/ha in year 2020. Our study highlights importance of fish and fishery long-term monitoring, and contributes to understand the driving factors in productivity, migration patterns and species ecology in the vital coastal ecosystems.

• Journal of Soil and Groundwater Environment
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• v.28 no.2
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• pp.1-11
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• 2023

Groundwater-surface water interaction was evaluated using water quality parameters (temperature and electrical conductivity), distributions of stable water isotopes (δ²H and δ ¹⁸O), and Rn-222 in lagoon water, groundwater, and seawater at three coastal lagoons (Songji (SJ), Youngrang (YR), and Sunpo (SP) Lagoon) in South Korea. From the results of composition and distributions of δ²H and δ¹⁸O, it was found that groundwater fraction of lagoon water in YR Lagoon (76%) was slightly higher than those of SJ (42%), and SP (63%) Lagoon. Based on Rn-222 mass balance model, groundwater discharge into SJ Lagoon in summer 2020 was estimated to be (3.2±1.1)×10³ m³ day^-1, which showed a similar or an order of magnitude higher than the results of previous studies conducted in coastal lagoons. This study can provide advanced techniques to evaluate groundwater-surface water interaction in coastal lagoons, wetlands, and lakes, and help to determine the effects of groundwater on coastal ecosystems.

• Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.333-337
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• 2011

A new and a unique Brachionus rotifer was found in Hwajinpo coastal lagoon in Gangwon Province, South Korea. This Brachionus certainly originated from the wild rather than from aquaculture stations because Hwajinpo coastal lagoon has been under rigorous control as a military protected area and therefore could not have been contaminated by aquaculture stations. The new strain was identified as Brachionus rotundiformis based upon its morphological characteristics. The parthenogenetic female of this new rotifer strain typically shows characters similar to those of B. rotundiformis, such as the pot shape of the body, rounded dorsal plate compared with flattened ventral plate, elliptical mictic egg, four frontal spines, six pointed occipital spines, non-nodal foot, two toes, trophi typical of the Brachionus genus with five uncus plates resembling comb teeth, one wide symmetrical manubrium and ramus, and no stiffened spine as is seen in freshwater Brachionus rotifers. Moreover, its lorica was rather small in size compared with other common rotifer strains that serve as live-food organisms (Guam, Thai, and Bali strains). This new and unique Korean brackish rotifer, a B. rotundiformis strain, was therefore named the National Fisheries Research and Development Institute (NFRDI) $N^{\circ}1$ rotifer strain.

• Journal of Ecology and Environment
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• v.35 no.4
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• pp.279-289
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• 2012

This study conducted a comparative analysis of benthic macroinvertebrate communities in the Fosu and Benya lagoons in Ghana, based on the anthropogenic effect on the two lagoons. Salinity, oxygen, temperature, conductivity, turbidity and pH were measured, invertebrate richness and species densities were determined. The AZTI Marine Biotic Index (AMBI) and multivariate statistics were used to determine the different responses of fauna to pollution. The fauna were categorized into five ecological groups based on the degree of tolerance of the different species to pollution: disturbance-sensitive species; disturbance-indifferent species, disturbance-tolerant species, second-order opportunistic species; and first-order opportunistic species. The Fosu Lagoon supported more pollution tolerant species, whereas the Benya Lagoon had more species that were sensitive to organic enrichment under relatively unpolluted conditions. Chironomus sp., which is adapted to virtually anoxic conditions, was the most abundant in the Fosu Lagoon whereas Nemertea sp. was the most abundant in the Benya Lagoon. The numerical and relative abundance (%) of all 7 taxa in the Fosu Lagoon was 1,359 and 92.35%, respectively. The numerical and relative abundance (%) of all 34 taxa in the Benya Lagoon was 2,459 and 87.52%, respectively. Expectedly, the level of dissolved oxygen in the less saline Fosu Lagoon was higher than that in the more saline Benya Lagoon. The reduced photoperiod and photosynthetic activities of aquatic plants might account for this trend. There is a need to implement comprehensive monitoring and management initiatives for sustaining the ecological health of coastal lagoons in Ghana in order to support the many people that depend upon these ecosystems for their livelihood.

• Journal of The Geomorphological Association of Korea
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• v.17 no.4
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• pp.41-52
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• 2010

Coastal lagoons(Ssangho, Gapyeongri wetland, Gunggaeho and Yeomgaeho) distribute densely around Osan-ri, Yangyang-gun. While Ssangho with the representative lagoon group in the East Coast has maintained the lagoon conditions of water surface since it was formed during the Climax of transgression, the others were formed at the swale areas of sand beach. They vary considerably in area reduction rates and position variations during the 20th century, and the causes examined can be divided into natural, human and other factors. They result in the lagoon aggradation stage by geomorphic development, reclamation due to rapid industrialization and urban development during the 20th century, and lacks of understanding on values of small coastal lagoon or errors in mapping and lags of survey techniques. Therefore, the plans for lagoon restorations should be proceeded by the individual properties of lagoons. The restorations of Ssangho are recommended preferentially and it is desirable to restore to the lagoon conditions of 1920s when the influences of human were minimum.

• Journal of Soil and Groundwater Environment
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• v.28 no.5
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• pp.12-24
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• 2023

The Songji lagoon is brackish environment with a mixture of saline and fresh water, and the interaction of groundwater-lagoon water creates a physicochemical gradient. Although some studies have been conducted on the hydrological and geochemical characteristics of the Songji lagoon, microbial ecological studies have not yet been conducted. In this study, we investigated the effect of groundwater and surface water interaction on water quality as well as microbial community changes in the Songji Lagoon using 16S rRNA gene sequencing. Hydrochemical analyses show that samples were classified as 5 hydrochemical facies (HF) and hydrochemical facies evolution (HFE) revealed the intrusion phase was more dominant (57.9%) than the freshening phase (42.1%). Higher microbial diversity was found in freshwater in comparison to saline water samples. The microbial community at the phylum level shows the most dominance of Proteobacteria with an average of 37.3%, followed by Bacteroidota, Actinobacteria, and Patescibacteria. Heat map analyses of the top 18 genera showed that samples were clustered into 5 groups based on type, and Pseudoalteromonas could be used potential indicator for seawater intrusion.

• The Korean Journal of Quaternary Research
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• v.15 no.2
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• pp.111-117
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• 2001

The deep cored sediments of the beach spit deposit in the inlet of the Songji lagoon(lake) have been studied in terms of the late Quarternary stratigraphy and relationship of the Holocene sea-level curve. Furthermore, the total content of heavy mineral sands from the established stratigraphic units(Unit I, II and III) varies due to the changes of depositional environments from continental to marine condition.

• Journal of The Geomorphological Association of Korea
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• v.17 no.2
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• pp.41-52
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• 2010

The paleovegetation environments relevant to the geomorphic properties were constructed by pollen analysis in the coastal dune (S1) and marginal trench (S4) of Ssangho at the Osan-ri site. The organic sand layer in the coastal dune (S1) accumulated on the remains of the Neolithic Age correlates to approximately 4,000 yr BP and the pollen zone can be divided with a boundary of approximately 2,000 yr BP. Pinus thunbergii definitely dominated and a small quantity of Quercus. Pollenzone I can be characterized by the dominance of AP and Compositae. The pollenzone II as the dominant period of NAP like Gramineae, Artemisia and Fagopyrum shows the properties of agricultural period. During the times of accumulation of upper organic layer in alluvial plain (S4), broad-leaved trees such as Alnus were dominant and Compositae, Gramineae, Artemisia, Typha, Umbelliferae and Persicaria show the high occurrence rates. The pollen composition of S4 indicates the agricultural activities with the dominance of NAP and correlates to the pollenzone II of the coastal dune (S1).