• Korean Journal of Food Science and Technology
• /
• v.40 no.5
• /
• pp.586-592
• /
• 2008

In this study, the nutritional components and functional activities of Sasa borealis leaf tea were evaluated. The proximate compositions were as follows; moisture 5.68%, crude protein 16.38%, crude fat 4.68%, nitrogen free extracts 32.37%, crude fiber 32.36%, and ash 8.53%, respectively. The mineral elements were as follows: K 2,133.83, Ca 1,144.09 and P 543.00 mg%, respectively. The amino acid contents of the Sasa borealis leaf tea were very rich in proline (1,275.26 mg/100 g) and deficient in cystine (71.49 mg/100 g). The major fatty acid components were linoleic acid (50.52%), palmitic acid (18.52%), and oleic acid (14.16%). Finally, based on our sensory evaluations, the $80^{\circ}C$ extracted Sasa borealis leaf tea evidenced the best overall quality. The contents of total phenol and total flavonoids of the 80% methanol and hot water extracts were 15.09, 7.69 mg/g and 12.03, 6.12 mg/g, respectively. The DPPH and $ABTS^+$ radical scavenging activities of the 80% methanol extract from Sasa borealis leaf tea were 86.87% and 83.85% at a concentration of 1.25 mg/mL. The 80% methanol and hot water extracts evidenced reducing power and inhibitory effects against acetylcholinesterase in a dose-dependent manner.

• Proceedings of KOSOMES biannual meeting
• /
• 2007.05a
• /
• pp.15-20
• /
• 2007

In this study, the authors investigated the change of marine environment by dumping dredged materials generated by construction of Busan New Port. There are lots of possibilities to impact an ocean ecosystem by toxic materials in the dredged material dumped in the open seas. As a result of analysis of environmental monitoring in the study areas 12 times a year, COD is II grade, T-N is I grade, T-P is between II and III grade. This result is same as another results of offshore in Korea. It seems unclear that it results from the change of water quality by dumping dredged material. However, according to the result of this investigation, it is not effected extensively to the marine environment by dumping dredged materials. We need further environmental monitoring in the interest sea areas, also need to keep on investigating the impact on the marine ecosystem by dumping dredged materials.

• Journal of Korea Water Resources Association
• /
• v.45 no.7
• /
• pp.729-741
• /
• 2012

Among the methods of precipitation data acquisition, a rain gauge station has a distinctive advantage of direct measurement of rainfall itself, but multiple stations should be installed in order to obtain areal precipitation data required for hydrological analysis. On the other hand, a rainfall radar may provide areal distribution of rainfall in real time though it is an indirect measurement of radar echoes on rain drops. Rainfall radars have been shown useful especially for forecasting short-term localized torrential storms that may cause catastrophic flash floods. CAPPI (Constant Altitude Plan Position Indicator), which is one of the several types of radar rainfall image data, has been provided on the Internet in real time by Korea Meteorological Administration (KMA). It is one of the most widely available rainfall data in Korea with fairly high level of confidence as it is produced with bias adjustment and quality control procedures by KMA. The objective of this study is to develop an improved way to extract quantitative rainfall data applicable to even very small watersheds from CAPPI using CIVCOM, which is a new image processing method based on a vector-based scheme proposed in this study rather than raster-based schemes proposed by other researchers. This study shows usefulness of CIVCOM through comparison of rainfall data produced by image processing methods including traditional raster-based schemes and a newly proposed vector-based one.

• Journal of the Korean association of regional geographers
• /
• v.15 no.1
• /
• pp.1-15
• /
• 2009

This study aims to provide preliminary data needed for establishing policies on the environment and disasters of Goryeong county. The main results are as follows. First, the present master plan of the region does not reflect local socio-economic and environmental conditions and the local people's opinion. Second, The air conditions of Gyeongbuk province and Goryeong county are within the permitted limit of air pollution of Korea. Third, the analysis of water pollution index in Nakdong river system shows improvement of water quality in both Andong and Goryeong. Fourth, the conditions of waste collection and disposal are improved in both Gyeongbuk province and Goryeong county. Fifth, in case of environmental pollutant emitting facilities of Gyeongbuk province, the proportion of 1st to 4th grade(relatively much more environmental pollutant emitting quantity than 5th grade) tends to be increasing. Sixth, environmental pollutant emitting facilities of Goryeong county are remarkably increasing in Dasan, Gaegin, Ssangrim, involving industrial complex. Finally, in case of disasters, it is relatively stable in Yecheon, Gumi, Uiseong, Yeongju and Cheongdo, while relatively unstable in Seongju, Gunwi, Yeongcheon, Chilgok, Mungyeong, Bonghwa and Goryeong.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.11 no.1
• /
• pp.56-67
• /
• 1999

It is desired to use a domestically manufactured ocean data buoy for the long-term operational ocean monitoring. The ocean data buoy manufacturing technology was introduced through the research cooperation with the Qingkong University of Taiwan. The introduced ocean data buoy system was further expanded and improved for more efficient application for the marine environmental monitoring in Korea. The size of the ocean data buoy is 2.5 m in diameter, which is smaller compared to the NOAA's 3.0 m discus buoy to allow easy land transportation and ocean deployment as well. From the dynamic response test of the buoy carried out numerically, it was shown that the measurement of waves with period greater than 4 seconds is acceptable. The measurement and control system of the data buoy were improved to increase the number of measuring parameters, to reduce power consumption and to enhance better data analysis and management. Each component of the improved data buoy system was described in detail in this paper. Water quality sensors of water temperature, salinity, DO, pH and turbidity were added to the system in addition to the marine meteorological sensors of wind speed and direction, air temperature, humidity, air pressure and wave. Inmarsat satellite communication system is used for the real-time data telemetry from the buoy deployed offshore. A field performance test of the improved and domestically manufactured buoy was carried out for a month at the open sea off Pohang together with DatawelI's Wave-rider buoy to compare the wave data. The results of the test were satisfactory.

• Korean Journal of Environmental Biology
• /
• v.31 no.4
• /
• pp.362-369
• /
• 2013

Phytoplankton and zooplankton communities were investigated from 8 weir sites of the Nakdong River system to provide basic information on plankton community after weir construction and to estimate its effects on major water quality parameters. The relationship between plankton community structure and environmental factors was analysed with CCA (Canonical Correspondence Analysis). The results suggested that discharge and total phosphorus and nitrogen concentrations are important factors determining the phytoplankton species composition. For zooplankton community, the difference in discharge between September and October induced different distribution pattern of zooplankton community with more homogeneous distribution with extreme dominance of rotifers during the high discharge season. Chlorophyll a concentration representing phytoplankton biomass has been suggested as the main environmental factor affecting zooplankton community followed by COD and total nitrogen concentration.

• Journal of Plant Biotechnology
• /
• v.47 no.1
• /
• pp.78-89
• /
• 2020

Tomato fruit quality is determined by the contents of various functional metabolites in addition to fruit appearance. To develop tomato cultivars with higher amounts of functional compounds, an efficient quantification method is required to identify the natural variations in the compounds in the tomato germplasm. In this study, we investigated tomato varieties, which included 23 inbred lines and 12 commercial F₁ cultivars, for their contents of seven watersoluble vitamins (vitamin C, vitamins B1, B2, B3, B5, B6, and B9) and five polyphenolic compounds (quercetin, rutin, kaempferol, myricetin, and naringenin chalcone). The results of high performance liquid chromatography and liquid chromatography-mass spectrometry showed that vitamin C and naringenin chalcone were the major water-soluble vitamins and polyphenolic compounds, respectively, and their abundance was highly variable depending on the cultivar. By contrast, the contents of vitamin B1, quercetin, and kaempferol were lowest among the cultivars. With regard to the relationship between metabolic compounds and fruit characteristics, a significant association was found in fruit size, indicating that cherry tomato varieties contain higher amounts of the compounds compared to large fresh-type varieties. However, no direct association was detected in fruit color, except for naringenin chalcone. The results of this study provide new insights on the quantification of metabolic compounds and the selection of breeding materials, which are prerequisites for the development of functional tomato varieties.

• Journal of agriculture & life science
• /
• v.46 no.3
• /
• pp.129-141
• /
• 2012

The purpose of this study was to monitor the stream flow of rural streams for investigating the status of stream depletion located downstream of irrigation reservoir. Bonghyun and Hai reservoirs area, located in Hai-myeon, the city of Gosung, Gyeongsangnam Province, were selected for study watersheds and streams. Stream flow monitoring was conducted 7 times from March to September, 2011. Stream flow was measured for 8 stations downstream from two reservoirs. The stream depletion was found in most of the downstream of reservoirs for the non-irrigation period and even in the irrigation period when there were a lot of antecedent precipitation. The correlation analysis for water quality data indicated that the correlation between BOD and T-N was highest for the reservoirs. The correlation between BOD, T-N, and turbidity was high for Hai reservoir and Bonghyeon reservoir. Continuous monitoring for rural streams located in downstream of reservoirs are required to quantify the status of stream flow depletion and determine the amount of environmental flows.

• Korean Journal of Ecology and Environment
• /
• v.54 no.3
• /
• pp.170-189
• /
• 2021

Environmental DNA (eDNA) is a genetic material derived from organisms in various environments (water, soil, and air). eDNA has many advantages, such as high sensitivity, short investigation time, investigation safety, and accurate species identification. For this reason, it is used in various fields, such as biological monitoring and searching for harmful and endangered organisms. To collect eDNA from a freshwater ecosystem, it is necessary to consider the target organism and gene and a wide variety of items, such as on-site filtration and eDNA preservation methods. In particular, the method of collecting eDNA from the environment is directly related to the eDNA concentration, and when collecting eDNA using an appropriate collection method, accurate (good quality) analysis results can be obtained. In addition, in preserving and extracting eDNA collected from the freshwater ecosystem, when an accurate method is used, the concentration of eDNA distributed in the field can be accurately analyzed. Therefore, for researchers at the initial stage of eDNA research, the eDNA technology poses a difficult barrier to overcome. Thus, basic knowledge of eDNA surveys is necessary. In this study, we introduced sampling of eDNA and transport of sampled eDNA in aquatic ecosystems and extraction methods for eDNA in the laboratory. In addition, we introduced simpler and more efficient eDNA collection tools. On this basis, we hope that the eDNA technique could be more widely used to study aquatic ecosystems and help researchers who are starting to use the eDNA technique.

• Journal of Environmental Impact Assessment
• /
• v.27 no.6
• /
• pp.595-603
• /
• 2018

This study was conducted to understand the growth of attached microbial community in small and medium streams of Gyeonggi-do and the removal efficiency of fluoride with changes in growth. The sites monitoring were carried out for 12 weeks at the P1 and P2(P1 is the point where the discharge water flows. P2 is the downstream point of about 2 km flow), and investigated the water quality and the biomass analysis of the attached microbial community. The growth of the attached microbial community increased up to the 7th investigation, and it was observed that detachment phenomenon occurred. Influencing factors about growth of the attached microbial community were flow rate, velocity, and organic material(T-N & T-P). Meanwhile, fluoride content of attached microbial community also tended to increase until the 7th investigation, and decrease from the 8th. It is assumed that fluoride content has also be reduced with the detachment phenomenon of the attached microbial community. It is expected that this will contribute to the evaluation and management of the use of attached microbial community as a means of stream management. The application of techniques using the attached microbial community should include basic investigation of factors that may affect the growth of the attached microbial community and replacement of the attachment plate according to the time of removal.