• Korean Journal of Soil Science and Fertilizer
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• v.39 no.4
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• pp.237-244
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• 2006

The SMG project has been driven to secure food and water resources by closing of the SMG dyke for the preparation of the unification of Korean peninsular. It was investigated for pollution loads, land use distribution and water consumption for environmental assessments in two watersheds, the Mankyeong River (MK) and the Dongjin River (DJ) to assess the role of agricultural land on the alleviation of pollution loads to the SMG basin. It is needed to give the priority in managing pollution sources to conserve freshwater in the Saemangeum (SMG) basin after the completion of the SMG reclamation from tideland. The MK has $700million\;m^3$ water of which 14.1% were used for living, 73.6% for agriculture and 12.3% for industry. The DJ has $505million\;m^3$ water of which 3.0% for living, 94.5% for agriculture and 2.5% for industry. As compared to proportion of each land of total area, agricultural land was 1.4 times larger, livestock farming 7 times larger, forest 0.74 times smaller, and built-up area 0.67 times smaller in DJ watershed than in MK watershed. Pollution sources in MK and DJ watersheds were originated at a higher proportion from population including the sewage disposal and a livestock farming area rather than from the land. Water consumption and land use distribution influenced the water quality of the rivers; DJ watershed had far lower value of electric conductivity, $BOD_5$, TN and TP than MK watershed. A large proportion of paddy field also influenced to reduce pollute loadings after rainfall; DJ watershed, which has a relatively large area of paddy fields, had a far lower delivery load after rainfall than MK watershed even though DJ watershed had large livestock farming area. As paddy fields was irrigated by Iksancheon water, 37% of nitrogen, 50% of phosphates and 14.0% of $BOD_5$ was removed by the paddy field just after flowing 150 meter, and rice plants could remove TN 100.0 kg, $P_2O_5$ 24.0 kg, and $K_2O$ 119.2 kg per hectare at harvest by irrigation of Iksancheon water. Conclusively, rice paddy fields played a positive role to conserve the water quality in the Iksancheon watershed.

• Journal of Mushroom
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• v.8 no.3
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• pp.122-130
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• 2010

Common mushroom production per area has been decreased and are up to less than 50% of the 1980 production. To determine the main reasons for the decrement, we performed this study. Two main reasons, which are mushroom disease and the low compost quality because of mechanized compost making, were assessed. In mechanized mushroom farms, nitrogen concentration in compost was lower than recommended and total compost quantity was about 100-150 $kg/3.3m^2$, which was also lower than usual. Our study revealed that higher nitrogen concentration (about 1.5%) in compost gave better production. Also, use of large amount of compost appeared to increase the mushroom production, although more insects and disease problems were observed. The relationships between the presences of microorganisms and occurrence of diseases were assessed by monitoring the microorganism densities near the mushroom farms. Higher number of microorganisms were observed near the mushroom farm area, compared to control region, Daechon beach. Most contaminating molds were found in the circulating fans, tunnel and culture room floor. The bacterial isolates were collected from the air in mushroom culture room and killed with 0.005% Benzalkonium solution, indicating treatment of Benzalkonium are the effective methods to sanitize the mushroom culture room.

• Korean Journal of Environmental Agriculture
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• v.21 no.4
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• pp.243-247
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• 2002

Irrigation water quality along Donjin river watershed was monitored to find a possible pollutant, for maintaining water quality to achieve food safety through water quality preservation of river. As a pollution indicators, such as Biological Oxygen Demand(BOD), Chemical Oxygen Demand(COD), Total Nitrogen(T-N), and Total Phosphate(T-P) in Dongjin river were examined from May to November in 2001. The results were as follows : The BOD level of Dongjin river ranged from 2.84 to 6.45 mg/L, which would be in a II$\sim$IV grade of the potable water criteria by Ministry of Environment. Averaged BOD level of downstream DJ6(After Jeongupcheon confluence) was 4.07 mg/L. The average COD level of Dongjin river ranged from 11.20 to 32.96 mg/L. COD level of DJ6 rapidly increased rapidly after the junction of Dongjin river and Jungupcheon because it showed the latter had relatively high pollution level. T-N content were significantly high in all sites of Dongjin river ranged through 4.16 to 5.84 mg/L. T-P examined high concentration than another thing point by 0.19 mg/L after Jeongupcheon confluence as BOD and COD. COD of main stream was expressed high concentration to dry season after rainy season. In case of T-P, pollution degree of dry season before rainy season appeared and examined that quality of water was worsened go by dry season after rainy season. The water quality of Dongjin river was deteriorated with inflow of Jungupcheon polluted by municipal and industrial sites near Jungup city.

• Korean Journal of Ecology and Environment
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• v.40 no.1
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• pp.82-92
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• 2007

In 2003, we evaluated biological water quality at twelve sites of Youngsan River using community analysis, fish compositions, and the Index of Biological Integrity (IBI). Of the twelve, four sites were the controls, which have no point sources in the upstream and the remaining eight sites were the impacted sites, which are influenced by wastewater treatment plant (WTP) and agro-industrial complex. Model values of the IBI, based on 12 sites data, averaged 28 (n=12, range: $18{\sim}44$), indicating fair poor condition according to the criteria of US EP A (1993). In the mean time, mean IBI in the control sites (S3, S5, S6, S11) was 42 (n=4, range: $38{\sim}44$), indicating a good condition, whereas mean IBI in the impacted sites was 21, indicating a poor condition. Mean IBI value in the control, thus, was greater by 2 fold than that in the WTP sites. The spatial pattern of IBI values was similar to the patterns of species diversity index and species richness index, except for Site 11, which was 1st order stream. Similarity analysis indicated that three groups were divided at the similarity level of 80%. One group was the streams influenced by wastewater and the other two groups were the pristine streams as the control, indicating that the stream health conditions are directly influenced by presence or absence of the point sources. Also, Pearson's correlation analysis showed that IBI values had negative correlation (r=0.899, p<0.001) with relative abundance of tolerance species, and had positive relation (r=0.890, p<0.001) with sensitive species. Overall, outcomes suggest that the point sources of the WTP might impact the species composition and ecological health, resulting in degradation of biological water quality.

• Korean Journal of Ecology and Environment
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• v.45 no.3
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• pp.263-270
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• 2012

The objectives of the study were to determine fish fauna and compositions during 2010~2011 in Walpyung Conservation Park along with analysis of fish community structures and trophic and tolerance guilds. Total number of species and individuals sampled were 31 and 2667, respectively and dominant species was Zacco platypus (46.6%) and subdominant species was Acheilognathus lanceolatus (8.7%), which were composed of >50% of the total. Total number of Korean endemic species including Microphysogobio yaluensis was 10 and the proportion of the individuals was 8.7%. Also, natural monument No. 454 of Iksookimia choii, which is endangered species and legal protected species, was sampled and the total number of individuals was only three. According to the analysis of fish community structures, species richness index in the mid-stream reach ($M_r$) was 3.145, which is higher than any other stream reaches ($U_r$ and $D_r$). In contrast, the richness index was 2.180 in the up-stream reach ($U_r$), which is minimum among the sampling sites. Species diversity index was 1.785 and 1.975, respectively in the headwater ($U_r$) and mid-stream reach ($M_r$) and the low values in the down-stream reach ($D_r$, 1.660) were due to the influences of pointsource (i.e., road construction) and non-point sources (sporadic agricultural spots). According to analysis of tolerance guilds, the proportion of tolerant species (TS), based on the number of individuals, was composed of 64.2% and sensitive species (SS) was only 3.3%, indicating a predominance of tolerant fishes in the compositions. The proportion of omnivore species (OS), however, was composed of 64.0% and insectivore species (IS) was 29.3%, indicating a predominance of omnivore fishes in the stream. The high proportions of tolerant and omnivore species in this stream indicates that the water quality and physical habitat environments were degradated in this system. For these reasons, especially natural monument and endemic fish species in this region should be protected from the massive constructions and required to provide efficient stream management strategies.

• Journal of Food Hygiene and Safety
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• v.21 no.1
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• pp.41-46
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• 2006

This study was carried out to survey the prevalence of foodborne pathogens in Sangshik products and their raw materials far the purpose of ensuring safety of those products in market, and establishing microbial regulatory standard. From 2002 to 2004, a total of 191 Sangshik products were purchased from market or mail-order sales, and major foodborne pathogens; E. coli, Salmonella, Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Listeria monocytogenes, Campylobacter jejuni, Yersinia enterocolitica, E. coli O157:H7, Vibrio parahaemolyticus were tested. B. cereus, C. perfringens and E. coli were detected from 29 samples (15.2%), 21 samples (11.0%) and 1 sample (0.5%), respectively. But other tested bacteria were not detected. For the identification of contamination source, 53 Sangshik ingredients were collected from 9 different manufacture factories. The results were similar with the Sangshik products. Aerobic plate counts were ranging from $1.0X10^3cfu/g\;to\;1.5X10^8cfu/g$. B. cereus was detected from 13 samples (24.5%), and counted as less than 100 cfu/g. C. perfringens were detected from 2 samples (3.8%), and counted as less than 100 cfu/g. Other foodborne pathogens were not detected except for B. cereus and C. perfringens. From the results, it was revealed that potential of microbial hazard by Sangshik was relatively low. However, it would be suggested that hygienic management and controling be needed for the prevention of growing contaminated pathogens and cross contamination during process and sale due to improper storage and management.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.4
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• pp.324-332
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• 2014

In order to reveal the long-term variations of water quality in Jinhae Bay, water qualities had been monitored at 9 survey stations of Jinhae Bay during 2000~2012. The surface and bottom waters concentrations of chemical oxygen demand (COD), dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), and chlorophyll-a (Chl.-a) were higher at the survey stations of Masan Bay than the stations of other Bays. Especially, station 1 which is located at the inner area of Masan Bay had the highest values in the concentrations of COD, DIN, and Chl.-a because there were terrestrial pollutant sources near the station 1 and sea current had not well circulated in the inner area of Masan Bay. In factor analysis, the station 1 also had the highest factor values related to factors which increase organic matters and nutrients in surface and bottom waters of Masan Bay. However, the stations (st.5, st.6, st.7, st.8, and st.9) of other Bays had lower values of the factors. In time series analysis, the COD concentrations of the bottom waters at 8 stations except for station 1 distinctly decreased. However, the COD concentrations of the surface waters showed no distinct decrease trends at all stations. In the concentrations of nutrients (DIN and DIP) of both surface and bottom waters, there were tremendous decrease trends at all stations. Therefore, these distinct decrease trends of the COD in bottom waters and the nutrients in surface and bottom waters of Jinhae Bay could have been associated with water improvement actions such as TPLMS (total pollution load management system).

• Journal of Wetlands Research
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• v.21 no.spc
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• pp.98-106
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• 2019

The coefficient and exponent of the MUSLE(Modified Universal Soil Loss Equation) runoff factor in the SWAT(Soil and Water Assessment Tool) model are 11.8 and 0.56 respectively, which are equally applied to the estimation of soil erosion regardless of land use. they could derive overestimation or underestimation of soil erosion, which can cause problems in the selection of soil erosion-vulnerable area and evaluation of reduction management. However, there are no studies about the estimation of coefficients and exponent for the MUSLE runoff factor by land use and their applicability to the SWAT model. Thus, in order to predict soil erosion and sediment behavior accurately through SWAT model, it is necessary to estimate the coefficient and exponent of the MUSLE runoff factor by land use and evaluate its applicability. In this study, the coefficient and exponent of MUSLE runoff factor by land use were estimated for Gaa-cheon Watershed, and the differences in soil erosion and sediment from SWAT model were analyzed. The coefficient and exponent of runoff factor estimated by this study well reflected the characteristics of soil erosion in domestic highland watershed. Therefore, in order to apply the MUSLE which developed based on observed data of US agricultural basin to the domestic watershed, it is considered that a sufficient modification and supplementation process for the coefficient and exponent of the MUSLE runoff factor depending on land use is necessary. The results of this study can be used as a basic data for selecting soil erosion vulnerable area in the non-point source management areas and establishing and evaluating soil erosion reduction management.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.243-248
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• 2011

The prevalence and distribution of hazardous microorganisms were investigated from the major perilla cultivation area at Milyang, Gyeongnam province, Korea. Aerobic plate count (APC) and coliform count of perilla leaves were 4.82 log CFU/g and 3.85 log CFU/g, respectively. E. coli, S. aureus and B. cereus were detected in 3.0% (4/114), 7.9% (9/114) and 46.5% (53/114) of examined perilla leaves. However, E. coli O157:H7, Salmonella spp, and L. monocytogenes were not detected. The distribution of hazardous microorganisms in perilla leaf cultivation environment were compared and the concentration of APC and coliform counts were more than 3.0 log CFU/(mL, g, $100cm^2$, hand) from most of the samples. S. aureus were detected from irrigation water, packing table, packing vinyl, hand, and clothes. Also, B. cereus was frequently detected from the examined samples. Especially, packing table and collection container were contaminated with maximum 5.5 log $CFU/100cm^2$ of B. cereus. Good Agricultural Practice (GAP) system should be introduced to farms to enhance the safety of perilla leaves.

• Korean Journal of Environmental Agriculture
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• v.24 no.2
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• pp.83-90
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• 2005

This study was conducted to evaluate the influence of pollutant loads on the water quality in the Mankyeong River from January 2002 to December 2004. The BOD level in upstream ranged from 0.58 to 1.57 mg $L^{-1}$, which would be in I grade according to water quality criteria by Ministry of Environment but BOD level in midstream and downstream was III grade. T-N contents were high in midstream and the average T-P level ranged from 0.06 to 2.70 mg $L^{-1}$. The point raw loads of BOD was high in Iksancheon, Mokcheonpo and Cheongha basin. The point raw loads of T-N and T-P were high in Iksancheon and Cheongha watershed. The non-point low loads of BOD were 3,931 kg $day^{-1}$, 2,870 kg $day^{-1}$ and 2,827 kg $day^{-1}$ in Mokcheonpo, Top and Jeonju watershed, respectively. The major source of BOD effluent load was population, that of T-N and T-P effluent loads was livestock. The delivered load of T-N were high in Jeonju, Mokcheonpo, Gosan, Iksancheon watershed in order. The delivered load of T-N was high in Jeonju watershed and that of T-P was high in Jeonju and Iksancheon watershed. The delivery ratio of BOD and T-N at dry season were below 100% except Mokcheonpo watershed. The delivery ratio of BOD and T-N at raining season were high in Gosan watershed.