• Journal of Ecology and Environment
• /
• v.48 no.1
• /
• pp.85-95
• /
• 2024

Background: In Korea, riparian zones and some floodplains have been converted into agricultural fields and urban areas. However, there are essential for maintaining biodiversity, as they are important ecological spaces. There are also very important spaces for humanity, as they perform various ecosystem services in a changing environment including climate change. Due to the importance of rivers, river restoration projects have been promoted for a long time, but their achievement has been insignificant. Development should be pursued by thoroughly evaluating the success of the restoration project. Ecological restoration is to accelerate succession, a process that a disturbed ecosystem recovers itself, with human assistance. Ecological restoration can be a test bed for testing ecological theories in the field. In this respect, ecological restoration should go beyond a 'simple landscaping exercise' and apply ecological models and theories in restoration practice. Results: The cross-section of the restored stream is far from natural rivers due to its steep slope and artificial material. The vegetation profiles of the restored streams did not reflect the flooding regime of the river. The species composition of the vegetation in the restored stream showed a significant difference from that of the reference stream, and was also different from that of an unrestored urban stream. Although species richness was high and the proportion of exotic species was low in the restored stream, the effect was offset by the high proportion of gardening and landscaping plants or obligate terrestrial plants. Conclusions: Based on both the morphological and ecological characteristics of the river, the restoration effect in the restored stream was evaluated to be very low. In order to solve the problems, a systematic adaptive management plan is urgently required. Furthermore, it is necessary to institutionalize the evaluation of restoration effects for the development of river restoration projects in the future.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2006.04a
• /
• pp.407-410
• /
• 2006

Studies were performed on evaluating the applicability of activated carbon bugs on dye tracer tests as tracer detectors by using its adsorption isotherm of the grained activated carbon. We preliminary conducted several standard adsorption and extraction tests and obtained the relationship between standard dye solution and detected concentrations from activated carbon samples in dry and wet conditions. the slopes of the regression line were 0.71 for wet condition and 0.74 for dried one. Field dye tracer tests were performed in a karst area, where several faults occur along a stream and pass the test area. We sampled water samples and activated carbon samples at three points in Hwangji Pond, where groundwater outflows from the karst conduit. According to the results of breakthrough curve analysis, the regional flow along the conduit, which is assumed to cause a karst conduit, was estimated as 0.18 m/day. The relationship between the concentrations of water sample and extracted activated carbon bugs shows the similar slopes with those from standard solution tests. This suggests that activated carbon could be useful as a dye tracer detector because the extraced concentration can be quantified.

• Journal of The Geomorphological Association of Korea
• /
• v.19 no.2
• /
• pp.1-15
• /
• 2012

The formative ages and processes of five natural abandoned channels in three types in Korea are studied. The former meandering channel in Seongsandong, Uljin-gun was abandoned due to the neck-cutoff of incised meander, Wangpi River in approximately 2.5~2.6ka and the abandoned channel in Bulyeong Temple, Uljin-gun was formed by the neck-cutoff of Wangpi River in approximately 90ka. Deduced from these results, it is judged to favorable for formation of abandoned channels by incised meander cutoff in interglacial or interstadial stages that had a better condition for meander cutoff because of active lateral erosion. Due to the corrosion of limestone joints in the underground of ridges between Hwangji River and Cheolam River, the channel in Gumumso, Taebaek-si was abandoned by the stream piracy connecting and combining the rivers into a limestone cave in approximately 40ka and higher lower reaches of Dong River than Banbyeon River in Seonbawi, Yeongyang-gun was turned to the abandoned channel throughout the stream piracy between the rivers in approximately 1.4ka. During Last Glacial Maximum in Jangcheon-ri, Chungju-si, Namhan River was divided into the eastern and western tributaries due to the alluvial island in approximately 10ka and then the western tributary was abandoned recently.

• Korean Journal of Ecology and Environment
• /
• v.53 no.1
• /
• pp.63-72
• /
• 2020

In this study, to discuss on the applicability of eDNA as a new method to investigate fish diversity at streams, we applied eDNA at 4 streams (Geum River, Ji Stream, Hwangji Stream, Seomjin River), where endangered species are inhabits, with conventional survey (cast net and kick net). The average (±standard deviation) number of species investigated by eDNA were 19 species (±4.4), and it was relatively higher than average of conventional survey, 10 species (±4.8). Most of case, in this study, eDNA was more efficient than conventional survey. However, there were errors on species identification of Korean endemic species and aliied species from eDNA, and it seems the universal primer (MiFish primer set) is not suitable for them. Furthermore, some of endangered species, caught by conventional method, was not detected by eDNA. As the present universal primer is not suitable for identify the every freshwater fish species in Korea, the complementing or development of universal primer is needed, and the eDNA application after species specific marker development for detecting specific species like endangered species should be considered. In conclusion, if the manual for field survey method by eDNA is developed, we expect applicability enlargement for water ecosystem survey.