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We assessed the naturalness of rivers based on the riparian vegetation index throughout the national territory of South Korea as a preparatory process for restoration to improve the ecological quality of rivers. The riparian vegetation index was obtained by incorporating the diversity of species and community, vegetation profile, and ratios of the number of species and areas occupied by exotic, obligate upland, and annual plants. The evaluation was conducted based on both the riparian vegetation index and each vegetation component. The result of the evaluation based on the riparian vegetation index showed that more than 70% of the river reaches were graded as less than “moderate” and exotic and obligate upland plants were more common than endemic aquatic plants. The reaches recorded as “very good” and “good” grades were usually restricted around the upstream of the north and central-eastern parts, whereas reaches of the other areas showed “poor” naturalness (less than “moderate”). The vegetation components selected for the evaluation showed a significant correlation with each other as well as the riparian vegetation index. The degree of contribution of each vegetation component showed that the vegetation profile played the most significant role, followed by species diversity, community diversity, and the ratio of area occupied by annual plants. The riparian vegetation index revealed a significant correlation with the indices based on other taxa such as benthic invertebrates, periphytic algae, and fish, habitat conditions in the waterway, and water quality based on biochemical oxygen demand (BOD). The diagnostic evaluation results imply that most reaches need ecological restoration. The reference information was prepared by incorporating the vegetation condition with the highest score in each reach in the diagnostic evaluation. The river reach was divided into five reaches of upper and lower valley streams, upstream, midstream, and downstream. Information on the reference vegetation for restoration was prepared with the stand profile including both horizontal and vertical arrangements of riparian vegetation and species composition classified by the reach divided into five types. The levels of restoration were determined based on the diagnostic evaluation results. The lower the naturalness grade, the higher the level of restorative treatment was recommended.

Length–weight relations (LWRs) for 16 freshwater fish collected from June to October 2018 in the Han River, South Korea, were estimated. The following species, representing the family Cyprinidae, were studied: Abbottina rivularis (Basilewsky, 1855); Acanthorhodeus chankaensis (Dybowski, 1872); Tanakia lanceolata (Temminck et Schlegel, 1846); Acheilognathus rhombeus (Temminck et Schlegel, 1846); Acheilognathus yamatsutae Mori, 1928; Carassius auratus (Linnaeus, 1758); Chanodichthys erythropterus (Basilewsky, 1855); Gnathopogon strigatus (Regan, 1908); Hemibarbus labeo (Pallas, 1776); Pseudogobio esocinus (Temminck et Schlegel, 1846); Pseudorasbora parva (Temminck et Schlegel, 1846); Pungtungia herzi Herzenstein, 1892; Sarcocheilichthys nigripinnis (Günther, 1873); Squalidus chankaensis Dybowski, 1872; Squalidus japonicus (Sauvage, 1883); Opsariichthys uncirostris (Temminck et Schlegel, 1846). The values of parameter b for all species were within the expected 2.5–3.5 range according to Froese (2006). The LWRs data for two species in this study, Acheilognathus rhombeus and Gnathopogon strigatus, were not previously available in FishBase.

Odonata species are sensitive to environmental changes, particularly those caused by humans, and provide valuable ecosystem services as intermediate predators in food webs. We aimed: (i) to investigate the distribution patterns of Odonata in streams on a nationwide scale across South Korea, (ii) to evaluate the relationships between the distribution patterns of odonates and their environmental conditions, and (iii) to identify indicator species and the most significant environmental factors affecting their distributions. Samples were collected from 965 sampling sites in streams across South Korea. We also measured 34 environmental variables grouped into six categories: geography, meteorology, land use, substrate composition, hydrology, and physicochemistry. A total of 83 taxa belonging to 10 families of Odonata were recorded in the dataset. Among them, eight species displayed high abundances and incidences. Self-organizing map (SOM) classified sampling sites into seven clusters (A&ndash, G) which could be divided into two distinct groups (A&ndash, C and D&ndash, G) according to the similarities of their odonate assemblages. Clusters A&ndash, C were characterized by members of the suborder Anisoptera, whereas clusters D&ndash, G were characterized by the suborder Zygoptera. Non-metric multidimensional scaling (NMDS) identified forest (%), altitude, and cobble (%) in substrata as the most influential environmental factors determining odonate assemblage compositions. Our results emphasize the importance of habitat heterogeneity by demonstrating its effect on odonate assemblages.

The objective of this study is to investigate the relationship between five air pollutants (PM(10), SO(2), NO(2), O(3), CO) measured on the daily basis, and adverse health symptoms using epidemiological surveillance data. The generalized estimated equation (GEE) model, a logistic regression analysis model, was used to estimate the effects of air pollution on children's daily health symptoms, focusing on the morbidity including both respiratory and allergic symptoms in four different cities. Analysis of the effects of each pollutant on children's respiratory and allergic symptoms demonstrated that CO affected all symptoms in all the study areas. When the concentration of SO(2) and NO(2) was elevated, upper respiratory symptoms increased significantly. In contrast, when the concentration of O(3) rose, the symptoms decreased significantly. The relationship between measured concentrations and health symptoms was site-dependent for each pollutant.

Landscape structure, habitat types, vegetation structure and biodiversity in the Bokha stream chosen as a reference stream were investigated to get ecological information necessary for restoration of urban stream degraded by excessive artificial interference. Landscape structure showed a slight change between before and after flooding. Habitat types of nine sorts were identified based on ecological information obtained from field survey such as micro-topography, hydrological characteristics, disturbance regime, and so on. Each habitat holds specific organisms to each site. Consequently, the number of plant communities, and species of benthos and fish increased as the kinds of habitat type increase. Ordination of habitat types based on vegetation, benthos, and fish data reorganized them into three groups of pool types of two kinds depending on whether they are connected to the water course or not and riffle one. Vegetation showed different stratification and species composition depending on topographical position in relation to disturbance cycle. Based on the results from this study, relationship between environmental heterogeneity and biodiversity was discussed and a restoration plan was suggested in a viewpoint of vegetation.

Aquatic oligochaetes are very common in streams, and are used as biological assessment indicators as well as in the biological management of organic-enriched systems. In this study, we analyzed the effects of environmental factors influencing the distribution of aquatic oligochaetes Limnodrilus hoffmeisteri in streams. We used 13 environmental factors in three categories (i.e., geography, hydrology, and physicochemistry). Data on the distribution of oligochaetes and environmental factors were obtained from 1159 sampling sites throughout Korea on a nationwide scale. Hierarchical cluster analysis (HCA) and nonmetric multidimensional scaling (NMDS) were performed to analyze the relationships between the occurrence of aquatic oligochaetes and environmental factors. A random forest model was used to evaluate the relative importance of the environmental factors affecting the distribution of oligochaetes. HCA classified sampling sites into four groups according to differences in environmental factors, and NMDS ordination reflected the differences of environmental factors, in particular, water depth, velocity, and altitude, among the four groups defined in the HCA. Furthermore, using a random forest model, turbidity and water velocity were evaluated as highly important factors influencing the distribution of L. hoffmeisteri.

To restore the forest ecosystem severely damaged by air pollution around industrial complexes, plants tolerant to the polluted environment were selected by transplant and pot culture experiments. A restoration plan by arranging those tolerant species was prepared based on the ecological diagnostic results on an area that requires restoration. Transplant experiment in Ulsan and Yeocheon areas, the representative industrial complexes in Korea, selected eight tolerant species of Quercus aliena, Q. acutissima, Q. dentata, Q. mongolica, Q. serrata, Ligustrum japonicum, Styrax japonica, and Poncirus trifoliata. Cultivation in the polluted soil transported from the Ulsan and Yeocheon industrial complexes chose five tolerant plants of Q. aliena, Q. acutissima, Q. serrata, Styrax japonica, and Alnus firma. A plan to restore the forest ecosystem of Mt. Dotjil, which experienced the severest ecosystem degradation in the Ulsan industrial complex, was prepared by applying those tolerant species along with treatment fo...

The purpose of this study was to assess current exposure of the population living in the Gwangyang industrial complex and other areas to heavy metals and, VOCs and to identify individual factors associated with urinary and blood levels of these chemicals. The study population was made up of 810 participants ranging in age from 7 to 87 years old at Gwangyang bay in the South Korea. The selected biomarkers represent the main agents to which a population like that of Korean is exposed every day, including 4 heavy metals in blood or urine (Pb in blood and As, Cd, Hg in urine), and VOCs in blood descriptive data analysis leads to mean concentrations of heavy metals, As, Cd, Hg and Pb of 7.34 μg/g cr, 1.04 g/g cr, 1.33 μg/g cr and 2.53 μg/dL, respectively. The mean concentration of benzene, ethylbenzene, tetrachloroehylene, toluene, m-/p-xylene and o-xylene in blood were 0.00 μg/L, 0.00 μg/L, 0.00 μg/L, 0.03 μg/L, 0.00 μg/L and 0.00 μg/L, respectively. The DNA microarray analysis using blood of 16 participants, control group (n=6) and sample group (n=10), showed that the two groups might belong to a different group through hierarchical clustering the present study provides reference values for selected pollutants for the general population in industrial complexes, which can be used for comparison purposes in further studies, since they are mostly within the reference ranges reported by other biomonitoring studies therefore, it would be possible to devise standards for identifying the environmental pollution and beforehand forecast. In addition, it will be the one of the scientific method to help reduce anxiety of residents lived in the polluted areas.