• Journal of Korean Society on Water Environment
• /
• v.24 no.2
• /
• pp.195-200
• /
• 2008

To analyze the riverine microbial community structure, genetic fingerprints and ecological indexes such as species abundances, diversity, evenness, dominance of targeted rivers in Gyeonggi Province were acquired and evaluated using terminal restriction fragment length polymorphism (T-RFLP) technique. Genetic fingerprinting technique such as T-RFLP, which is able to show the microbial community clearly unlike traditional culture-dependent techniques, was thought to be useful to analyse the riverine microbial ecosystem under various factors. Riverine ecosystem evaluation using visible organisms would give biased results with time, targeted organism and researcher. But, T-RFLP, which can exclude the subjected biases such as culture condition and identification, would be an option to understand natural ecosystem by including the microorganisms that defy culture but perform important functions.

• Journal of Korea Water Resources Association
• /
• v.42 no.6
• /
• pp.481-491
• /
• 2009

In this study, a comprehensive field monitoring was conducted to understand habitat conditions of fish species in the upper Geum river. Based on the monitoring data, riverine health conditions such as composition ratio of fish species, richness and dominance indexes, bio-diversity (dominance index, diversity, evenness and richness), and index of biological integrity were assessed, and optimal ecological flowrates were estimated using the habitat suitability indexes established for three fish species Coreoleuciscus splendidus, Zacco platypus and Pseudopungtungia nigra selected as icon species using the physical habitat simulation system (PHABSIM). The total number of species sampled was 20 species, and two sensitive species of C. splendidus (22.4%) and Z. platypus (22.0%) dominated the fish community. The estimated IBI values ranged from 34 to 42 with average being 38 out of 50, rendering the site ecologically fair to good health conditions. An optimal ecological flowrate of 9.0 cms was recommended for the representative fish species at the site.

• Korean Journal of Environment and Ecology
• /
• v.23 no.6
• /
• pp.516-527
• /
• 2009

We assessed fish fauna and habitat suitability indexes in the Geum river basin. Field monitoring was conducted for ecological and habitat condition assessment at 23 sites from October 2007 to March 2009. The habitat suitability indexes established for dominant fish species using the monitoring data were employed to assess riverine health conditions such as composition ratio of fish species, richness and dominance indexes, bio-diversity(dominance index, diversity, evenness and richness), and water depth, velocity and substrate size. Twenty-one species(42%) including Rhodeus uyekii and Pseudopungtungia nigra were found endemic out of the 50 species in 11 families sampled during this study period. The most frequently found one was Zacco platypus(34.3%) followed by Z. koreanus(10.2%) and Coreoleuciscus splendidus(8.4%). For Z. platypus, the dominant fish species in the basin, the favored habitat conditions were estimated to be 0.1~0.9 m for water depth, 0~0.9m/s for flow velocity and silt(<0.1mm)~cobbles(100.0~300.0mm) for substrate size, respectively. Overall, it was concluded that the Geum river basin has been relatively well protected from the anthropogenic disturbance for the legally protected species including the endemic species studied in this study.

• Ecology and Resilient Infrastructure
• /
• v.1 no.1
• /
• pp.39-48
• /
• 2014

In order to establish fundamental data for stream restoration and environmental flow, we investigated optimal ecological flowrate (OEF) and riverine health condition in the Chogang Stream, a tributary to Geum River, Korea. The number of fish individuals sampled in this period were 4,669 in 36 species of 9 families. The most abundant species was Korean chub (Zacco koreanus, 34.0%) followed by pale chub (Z. platypus, 22.6%) and Korean shinner (Coreoleuciscus splendidus, 13.3%). Index of biological integrity (IBI) and qualitative habitat evaluation index (QHEI) values decreased from upstream to downstream along the stream. The estimated IBI value ranged from 27.9 to 38.6 with average 32.2 out of 50, rendering the site ecologically fair to good health conditions. OEF was estimated by the physical habitat simulation system (PHABSIM) using the habitat suitability indexes (HSI) of three fish species Z. koreanus, C. splendidus and Pseudopungtungia nigra selected as indicator species. In Z. koreanus, HSI for flow velocity and water depth were estimated at 0.1 to 0.4 m/s and 0.2 to 0.4 m, respectively. In P. nigra, HSI for flow velocity, water depth and substrate size were estimated at 0.2 to 0.5 m/s and 0.4 to 0.6 m and fine gravel to cobbles, respectively. OEF values increasing from up to downstream was found to increase, weighted usable area (WUA) values increased accordingly.