• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.5363-5368
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• 2014

This study examined contribution rate on the Soyangho Lake watershed based on the flow regime, and seasonal change was evaluated by calculating the delivery pollution load of the drainage area of Soyangho Lake watershed. According to the contribution rate of the drainage area by the flow regime change, Inbukcheon Creek watershed's SS and T-P entry have recorded abnormal Six month flow and a contribution rate of 46% and 51% during the Low-water flow period. At the same time, the T-P recorded a 49.5% contribution rate and a contribution rate of 48.5% during the Low-water flow period. In sequence, Inbukcheon creek's SS entry recorded a comparatively higher contribution rate than the other drainage area, which are 39.6% and 44.3% during the entire season and 53.8% for T-P, as a result of observing the contribution rate based on the seasonal changes. The T-N at the Naerincheon Creek watershed for the entire season recorded a contribution rate between 39.6% and 44.3%. Overall, Inbukcheon Creek watershed's SS and T-P entry and Naerincheon creek's T-N had a high contribution rate on contaminant spill.

• Journal of Environmental Science International
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• v.14 no.3
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• pp.279-288
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• 2005

The vascular plant at Korea CC was researched in 95 taxa and Korea CC had the highest number of vascular plants among the ponds of 9 golf courses in the capital region. The number of vascular plants at Eunhwasam CC was 21 taxa which followed as the second most. Most of the vascular plants surveyed consist of a mon-ocotyledon with 1-2 years of life and a dicotyledon as perennial. The ratio between an introduced species of pond vegetation and planting species from Jisan CC is $52.3\%$, which is the highest. The lowest ratio of those is $21.1\%$, which is from Pine Creek Cc. Pine Creek CC has 25 plant communities in total, with 16 semi-natural and natural communities and 9 planting or introduced communities. Pine Creek CC has the most varied plant communities among 9 golf clubs. There are plant communities of semi-natural and natural vegetation from all ponds, and there are 12 aquatic plant communities at disturbance or planting vegetation. We found out that Pine creek CC has more natural communities than disturbance or planting communities compared to other golf clubs, and there is not any natural vegetation at Pristine Valley CC. According to value grade from assessment indicator, the natural aspect of Seseoul CC and Eunhwasam CC are the lowest among 9 golf clubs. Taeyoung CC, Eunhwasam CC, Jisan CC, Seseoul CC are superior in made vegetation among the group in terms of euclidean similarity coefficient on natural aspect and are classified as one group. Korea CC and Pristine Valley CC have distinguished semi-natural vegetation and Midas Valley CC and Pine Creek CC, which have a relatively high natural aspect, are classified as one group. Blue Heron CC is separated from other groups into its own group because it has a high value of scenery in particular. In conclusion, there is a correlation between the natural aspect of a pond and size of vegetation.

• Journal of Environmental Impact Assessment
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• v.3 no.2
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• pp.25-32
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• 1994

This study was carried out as the Anyang creek water quality management using Geographic Information System (GIS) is the purpose of this pilot project to apply a GIS to environmental management field. Analysis of water quality data has been investigated using GIS with modeling of water quality management for the Anyang creek. The results of this study are summarized as follows: 1. The concentration of Mercury in sediment was increased rapidly nearby A26(Nightsoil Treatment Plant) and maximum was showed at A18 (Imgok bridge). Cadmium was increased rapidly at A35(Chulsan bridge). 2. River water quality management using visible computer system as GIS is effective to make decision for water quality management plan and database of environmental factors should be completed before applying GIS. 3. When water pollution accident is occurred in the river water system, pollutant source can be traced and analysed systematically using GIS to manage pollutants discharged into the river water system.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.789-792
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• 1999

Reinforced concrete structures covered creek for road vehicle located in urban areas have been experiencing corrosion of concrete and reinforcing steel caused by $H_2S$ gases generated by anaerobic bacterial. H2S gases react with oxygen and water to form sulfuric acid ($H_2SO_4$). This acid chemically attacks concrete, and sulfate ions penetrate into the concrete, causing rebar corrosion. In this work, to determine the conditions of RC culvert boxes which were constructed in the 1970s, various tests were conducted, including carbonation depth, compressive strength, half-cell potential measurements, and XRD analyses. Results indicated that the concrete deterioration was caused by sulfate attack and rebar corrosion. This paper discusses the evaluation on the durability of reinforced concrete structures covered creek for road vehicle.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.163-167
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• 2004

Creeks, defined by creek's improvement law, have strong localities in the flow characteristics and environmental condition. During the recent ten-years, lots of flood damages have occurred rather in the creeks. However, quantity and stream design information are poor while the national-class and local-class streams have sufficient. This causes a problem on improving the safety from flood. This study focuses on assessment of practical applicability for design flood estimation models. For this, Rational formula, Clark's model and Nakayath synthetic unit hydrograph method are estimated by data of the creek comprehensive improvement plan report, etc.

• Journal of the Mineralogical Society of Korea
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• v.17 no.1
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• pp.37-47
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• 2004

Sulfates such as alunite and schwertmannite formed under oxidation condition play a important role in geochemical processes taken place at waste dumps and a creek from Dalseong mine, Daegu. Water chemistry shows pH decreases from upstream toward downstream creek, mainly due to formation of schwertmannite that is the most abundant phase along the creek. The removal of Al from the creek is preferentially attributed to formation of Al-bearing minerals and Al-sulphates. Among them, alunite is the most important Al-sink phase that occurs at higher pH than $pK_1$, Al hydrolysis constant. With high saturation index, alunite formed at the creek has a spherical form, commonly associated with schwertmannite. Secondary minerals formed on the surface of altered or weathered surfaces of heavy metals from the wasted dump that underwent severe oxidation, where alunite has characteristic habits which are spheric, radiating, and botrytis-like aggregates. Natroalunite occurs in association with alunite, or as mixtures of both of them. Because the pH decreases with distance due to formation of schwertmannite, although total contents of dissolved ions slowly lessen at least in the AMD, it is expected that the minerals precipitated at the creek can be exposed to subsequent dissolution, which may induce possible environmental problems.

• Spatial Information Research
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• v.14 no.4 s.39
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• pp.363-377
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• 2006

Mean annual soil loss was calculated and critical soil erosion areas were identified for the Congaree River Basin in South Carolina, USA using the Revised Universal Soil Loss Equation (RUSLE) model. In the RUSLE model, the mean annual soil loss (A) can be calculated by multiplying rainfall-runoff erosivity (R), soil erodibility (K), slope length and steepness (LS), crop-management (C), and support practice (P) factors. The critical soil erosion areas can be identified as the areas with soil loss amounts (A) greater than the soil loss tolerance (T) factor More than 10% of the total area was identified as a critical soil erosion area. Among seven subwatersheds within the Congaree River Basin, the urban areas of the Congaree Creek and the Gills Creek subwatersheds as well as the agricultural area of the Cedar Creek subwatershed appeared to be exposed to the risk of severe soil loss. As a prototype model for examining future effect of human and/or nature-induced changes on soil erosion, the RUSLE model customized for the area was embedded into ESRI ArcGIS ArcMap 9.0 using Visual Basic for Applications. Using the embedded model, users can modify C, LS, and P-factor values for each subwatershed by changing conditions such as land cover, canopy type, ground cover type, slope, type of agriculture, and agricultural practice types. The result mean annual soil loss and critical soil erosion areas can be compared to the ones with existing conditions and used for further soil loss management for the area.

• Journal of Korea Water Resources Association
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• v.36 no.2
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• pp.285-300
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• 2003

An event-based, kinematic, infiltration-excess, and distributed rainfall-runoff model using weather radar and Geographic Information System(GIS) was developed to acknowledge and account lot the spatial variability and uncertainty of several parameters relevant to storm surface runoff and surface flow The developed model is compatible with raster GIS and spatially and temporally varied rainfall data. To calibrate the model, Monte Carlo simulation and a likelihood measure are utilized; allowing for a range of possible system responses from the calibrated model. Using rain gauge adjusted radar-rainfall estimates, the developed model was applied and evaluated to a limited number of historical events for the Ralston Creek and Goldsmith Gulch basins within the Denver Urban Drainage and Flood Control District (UDFCD) that contain mixed land use classifications. While based on a limited number of Monte Carlo simulations and considered flood events, Nash and Sutcliffe efficiency score ranges of -0.19∼0.95 / -0.75∼0.81 were obtained from the calibrated models for the Ralston Creek and Goldsmith Gulch basins, based on a comparison of observed and simulated hydrographs. For the Ralston Creek and Goldsmith Gulch basins, Nash and Sutcliffe efficiency scores of 0.88/0.10, 0.14/0.71, and 0.99/0.95 for runoff volume, peak discharge, and time to peak, respectively, were obtained from the model.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.3
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• pp.12-21
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• 2012

The proximities of Cheonggye creek was a maj or space for the gathering of large populations from the past times and it is also a place containing the joy, anger, sorrow, pleasure and lives of the citizens. The Cheonggye creek which flowed downtown of Seoul throughout many historical events had disappeared into history completely in the modernization process due to the contamination with life sewages and overflow. However, the city authority of Seoul decided to restore it to its shape before covering the creek by means of dismantling the old elevated ways in Cheonggye creek in line with the Large Scale City Movement Project to revive the grey city and to improve the quality of the city landscape in 2002. The cultural space was created by activating the old town sphere in Cheonggye Creek and the amenities of the giant city was improved by the cultural and natural wave created along the creek. In addition, the educational opportunity has been provided to the citizens by means of reviving its historical nature. The design and cultural value of the Cheonggye Plaza were restored for the mean time and the urban environment requested during modem times was established. The Cheonggye Plaza which heightened the balanced development in Seoul which has been developed in an unbalanced way by dividing into northern and southern area of the river is very meaningful in the viewpoint of the landscape architect who designs the urban space. The re-birth as a cultural space of downtown owing to the efforts of the said cultural catalysts is meaningful.

• Korean Journal of Ecology and Environment
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• v.37 no.1 s.106
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• pp.106-111
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• 2004

Fecal coliform bacteria is one of the most common cause of water quality impairments in Virginia, USA. Instream concentrations of fecal coliform (FC) bacteria were routinely monitored to assess surface water quality of the Polecat Creek watershed. Median concentration in water samples collected from 1995 to 2000 ranged from 80 cfu/100 mL to t 70 cfu/100 mL, while geometric mean concentrations ranged from 81 cfu/100 mL to 141 cfu/100 mL. The dilution and deposition by Lake Caroline may cause to lower FC concentration at monitoring site QPB, as compared FC concentration at QPD. Higher in-stream FC concentration occurred during the summer period(June-August), and lower concentration typically occurred during the winter period (December-February). This is due to more cattle in streams, and greater survival and regrowth of FC bacteria under warmer condition. The findings of this study can be helpful in planning the water quality monitoring program to avoid the inaccurate assessment of water quality due to the timing of sample collection.