• Journal of Conservation Science
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• v.34 no.5
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• pp.333-343
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• 2018

This study was conducted to evaluate the conservation environment by monitoring temperature and humidity for two years and mapping the remaining pigments of mural paintings to diagnose the conservation state of mural paintings of Royal Tombs in Neungsan-ri. We evaluated the characteristics of condensation in the tomb. Compared with the results of a 2008 survey, we conducted state change of mural paintings in the tomb. The temperature in the main room, which has an annual average soil temperature distribution at 5 m depth in Korea, is maintained at $13{\sim}18^{\circ}C$. The temperature range of the main room was between less than $0.1^{\circ}C$ to $0.5^{\circ}C$, and the diurnal variation of temperature between summer (June to September) and winter (December to January) is the greatest. Condensation is more concentrated in the summer because the outdoor air was typically at higher temperatures than the main room inflows in the tomb. Mapping the remaining pigment composition and particle distribution of mural paintings showed that it was in the range of 36.72~39.53% of the wall area. The pigment range was confirmed to be the same as it was in 2008, through ultraviolet fluorescence reaction and infrared ray investigation. Therefore, the underground environment that receives dew condensation in the summer has been stable since 2008. However, continuous monitoring is needed because the deterioration of mural painting proceeds considerably after excavation and only a small percentage of the pigments survive.

• Journal of Food Hygiene and Safety
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• v.32 no.6
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• pp.485-492
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• 2017

This study investigated to determine the microbial contamination levels of strawberries at harvest and distribution stages and to suggest a control measure for reducing the microbial contamination of strawberries by replacing worker's gloves used at harvest and distribution stages. According to the monitoring results, the contamination levels of total aerobic bacteria (TAB) were in the order of soil ($7.12{\pm}0.61{\log}_{10}CFU/g$), gloves ($6.06{\pm}1.80{\log}_{10}CFU/cm^2$), strawberry ($3.28{\times}0.98{\log}_{10}CFU/g$), and water ($3.08{\pm}0.55{\log}_{10}CFU/g$) at harvest stage. TAB of strawberry at was harvest stage reduced from $3.28{\pm}0.98{\log}_{10}CFU/g$ to $1.85{\pm}0.21{\log}_{10}CFU/g$ and $2.6{\pm}0.30{\log}_{10}CFU/g$ at cold and room temperature storage, respectively. By the replacement of worker's gloves and distribution temperature, TAB levels of the strawberries were significantly reduced when compared to those of the strawberries treated without replacement of worker's gloves and distributed at room temperature. For reusing the replaced gloves, washing with a commercial disinfectant, clorox, was effective to reduce microorganisms contaminated on the worker's gloves. These results demonstrated that appropriate replacement of gloves at the harvest and distribution stages is an effective method for reducing microbial contamination of fresh strawberries.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.1
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• pp.76-87
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• 2019

The purpose of this study was to evaluate the performance of and to derive future maintenance-management measures of the constructed alternative habitat for the Kaloula borealis at the University of Seoul, examining the period between 2015-2017. The research was constructed in 2014 and in a $191m^2$ area. The performance evaluation was divided into maintaining the habitat of the target species, maintaining the population and reproduction rates of the target species, maintaining the habitat of the wild species, the resilience of natural ecosystems, and the harmony with the surrounding environment. In terms of maintaining the habitat of the target species, soil collected from the existing habitat of the Kaloula borealis and was the depth was increased to 30cm in the alternative habitat. An artificial water supply was required every year during the supporting the spawning and hatching of other amphibians along with the Kaloula borealis. The sources of water of the alternative habitat were both rain and tap water, as it cannot be maintained naturally. Additionally, the Kaloula borealis thrived because it inhabited the research site and the average temperature was $26.2^{\circ}C$ from April-June, which is when the Kaloula borealis spawns. In terms of maintaining the population and reproduction rates of the Kaloula borealis, they were evaluated to have stable rates of reproduction. In terms of maintaining the habitat of the wild species, studies on vegetation and the structure of the characteristics of prey or predators will be needed. Also, alien species, such as Humulus japonicus and Bidens frondosa needed to be removed to maintain the wetland ecosystem of the wild species. In the assessment of the resilience of the natural ecosystems, the mud was monitored, noting the changes in the depth of water, with steps taken to reduce the leakage of water. The mud collected from the Haneul Pond wetland, which is located around the research site was piled up. Also, partial mowing management and the inducement of a natural vegetation colony was required for vegetation management. It was also necessary to create porous spaces, such as old trees and tree branches to create a habitat with hiding places and feeding and spawning places for small organisms. In terms of the harmony with the surrounding environment, the following threat factors needed to be managed: amphibian roadkill by vehicles and pedestrians and artificial draining due to nearby user access. Based on the monitoring results, alternative habitat management measures presented the promoting various waterside structures, in which amphibians can spawn and hide in, managing the water environment consistently, managing the vegetation, focused on the habitat of the wild species, and managing the surrounding environment for the habitat. The creation of an alternative habitat should be managed through monitoring, reflecting the characteristics of the changes in the site. Also continuing efforts are also needed to improve the habitat of the target species.

• Research in Plant Disease
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• v.28 no.4
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• pp.221-230
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• 2022

The fire blight caused by Erwinia amylovora (Ea) was first reported in 2015 in Korea, and the disease has rapidly spread to 22 regions until 2021. In Korea, all host plants in the apple and pear orchards where fire blight occurred should be eliminated and buried by the Plant Protection Act. To prevent the spread of the disease, all burial sites were prohibited from planting the new host plants for the next three years. To confirm the eradication efficiency of Ea and the reoccurrence of fire blight, the surveillance facilities were established on three burial sites from 2019 to 2020 in Anseong-si, Gyeonggi-do, and Chungju-si, Chungcheongbuk-do. As host plants, five apple trees of fire blight-susceptible cultivar 'Fuji', were planted in each facility. All facilities were enclosed with fences and nets and equipped with two CCTVs, motion sensors, and several other sensors for recording weather conditions to monitor the environment of the sentinel plants in real-time. The sentinel plants were checked for the reoccurrence of fire blight routinely. Suspicious plant parts were collected and analyzed for Ea detection by loop-mediated isothermal amplification polymerase chain reaction and conventional polymerase chain reaction. Until November 2022, Ea has not been detected in all sentinel plants. These results might support that the burial control of infected plants in soil works efficiently to remove Ea and support the possibility to shorten the prohibition period of host plant establishment in the burial sites.

• Korean Journal of Remote Sensing
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• v.39 no.3
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• pp.325-338
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• 2023

Korean fir (Abies koreana Wilson) is one of the most important environmental indicator tree species for assessing climate change impacts on coniferous forests in the Korean Peninsula. However, due to the nature of alpine and subalpine regions, it is difficult to conduct regular field surveys of Korean fir, which is mainly distributed in regions with altitudes greater than 1,000 m. Therefore, this study analyzed the vegetation change trend of Korean fir using regularly observed remote sensing data. Specifically, normalized difference vegetation index (NDVI) from Moderate Resolution Imaging Spectroradiometer (MODIS), land surface temperature (LST), and precipitation data from Global Precipitation Measurement (GPM) Integrated Multi-satellitE Retrievalsfor GPM from September 2003 to 2020 for Hallasan and Jirisan were used to analyze vegetation changes and their association with environmental variables. We identified a decrease in NDVI in 2020 compared to 2003 for both sites. Based on the NDVI difference maps, areas for healthy vegetation and high mortality of Korean fir were selected. Long-term NDVI time-series analysis demonstrated that both Hallasan and Jirisan had a decrease in NDVI at the high mortality areas (Hallasan: -0.46, Jirisan: -0.43). Furthermore, when analyzing the long-term fluctuations of Korean fir vegetation through the Hodrick-Prescott filter-applied NDVI, LST, and precipitation, the NDVI difference between the Korean fir healthy vegetation and high mortality sitesincreased with the increasing LST and decreasing precipitation in Hallasan. Thissuggests that the increase in LST and the decrease in precipitation contribute to the decline of Korean fir in Hallasan. In contrast, Jirisan confirmed a long-term trend of declining NDVI in the areas of Korean fir mortality but did not find a significant correlation between the changes in NDVI and environmental variables (LST and precipitation). Further analyses of environmental factors, such as soil moisture, insolation, and wind that have been identified to be related to Korean fir habitats in previous studies should be conducted. This study demonstrated the feasibility of using satellite data for long-term monitoring of Korean fir ecosystems and investigating their changes in conjunction with environmental conditions. Thisstudy provided the potential forsatellite-based monitoring to improve our understanding of the ecology of Korean fir.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.6
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• pp.137-148
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• 2008

There have been many cases of using wetlands as an alternative in controlling stormwater, treating mining leachate, and agricultural discharge, and so on, recently. The reality is, however, that the wetlands are not properly applicable because of the lack of enough longterm data for wetlands due to the difficulty of long-term monitoring. Therefore, this study tries to analyze the storage of Upo, Mokpo, Sajipo, and Jjokjibeul in Topyeong watershed using SWAT(Soil and Water Assessment Tool) model, one of the long-term runoff hydrologic model, for the purpose of generating the long-term data and analyzing the hydrologic behavior of wetlands based on the generated data. Also, the changes in runoff at the outlet are analyzed after applying the simulation of constructing washland in Topyeong watershed and the storage in Upo is analyzed. The result shows that the runoff at the outlet of the watershed is decreased in rainy season from July to August and increased in dry season from December to February. In addition, the analysis of Upo storage concludes that Upo can be influenced by the construction of the washland. The duration curve of washland is then analyzed in order to evaluate the wetland's sustainability in terms of washland and it appears that the runoff of washland is simulated to be less than that of the existing wetland. Moreover, runoffs of some washlands are simulated to be less even in wet season. These results lead to the fact that there should be further hydrologic management for constructed washland. Then, the changes in loads (TN and TP) because of constructing washland are analyzed. The result shows that the loads are reduced because of the construction. Also, the changes in loads due to the construction of buffer strips are analyzed to compare the load reductions caused by a washland. Finally, REMM model, a riparian management model, is applied to overcome the hydrologic ambiguousness of SWAT model, and then, the SWAT model results are compared to those of REMM.

• Korean Journal of Environment and Ecology
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• v.22 no.6
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• pp.679-690
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• 2008

The objectives of this study are to investigate and analyze the vegetation structure and population dynamics of Berchemia racemosa habitats in the Weolmyung park in Gunsan city, and base on that to seek the ecological habitat conservation plan for the Berchemia racemosa. In results, the Berchemia racemosa habitats are located at $81{\sim}93$ meters above the sea level, in steep seaside slope of a mountain. The soil texture are silt loam mainly and soil pH were $4.1{\sim}5$. The vascular plants in the Berchemia racemosa habitats has been analyzed as 61 taxa; 33 families, 51 genera, 54 species, 6 varieties, and 1 forms. Berchemia racemosa as a Specific plant species by floral region was the class V. Berchemia racemosa habitats were classified into 7 vegetation communities of Quercus serrata community(A1), Alnus firm a community(A2), Platycarya strobilacea community(A3), Robinia pseudoacacia community(A4) and 3 Pinus densiflora communities(B1, B2, B3). The importance value of Berchemia racemosa were 30%(A1), 15%(A2), 27%(A3), 65%(A4), 18%(B1), 45%(B2) and 35%(B3) on shrubs layer and 12, 27, 20, 18, 11, 18, 21 % on herb layer. The constant companion species with Berchemia racemosa were Stephanandra incisa and Ligustrum obtusifolium. Total 103 populations appear in the 7 Berchemia racemosa habitats. Their spatial distribution pattern were clumped for the most part. The average height was 133cm, the root color diameter was 4.4cm and the ramification branch number was 9.4. From the results of this study, it is suggested the continued monitoring and the active protection measures for the Berchemia racemosa habitats.

• Journal of Soil and Groundwater Environment
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• v.12 no.2
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• pp.9-19
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• 2007

This study investigated the interaction between groundwater and stream water systems, which is caused by the artificial weir on streambed, enforcing external stresses on the groundwater system. The study area is in Nami Natural Recreation Woods located in Chungcheongnam-do Geumsan-gun Nami-myeon Geoncheon-ri. In this study both of hydrophysical methods (hydraulic head) and hyrdochemical investigations (pH, EC, major ion analysis) were applied. In order to identify the relationship between each of study results, cross-correlation analysis is performed. From results of hydrophysical methods, water level fluctuation at BH-14, installed by the weir, shows the double-recession pattern much more frequently and much higher amplitudes than the fluctuation at each of other monitoring wells. Using the results by hydrochemical investigations, hydrochemical properties at BH-14 is similar to the hydrochemical characteristics in stream water. To analyze the interrelationships between the results from each of applied methods, cross-correlation analysis was applied. Results from the correlation analyses, water levels at BH-14 and stream weir showed the highest cross-correlation in hydrophysical aspects. On the other hand, the correlation between stream weir and bridge was the highest in hydrochemical aspects. The difference between the results from each of methods is due that the hydrophysical response at BH-14, such as water level, is induced by the pressure propagation-not with mass transfer, but the hydrochemical interaction, caused by mass transport, takes much more times. In conclusion impermeable artificial weir on streambed changes the interfacial condition between the stream and surrounding aquifers. The induced water flux into the groundwater system during flood period make water level at BH-14 increase instantly and groundwater quality higly similar to the quality of stream water. Referred similarities in both of water level and water quality at BH-14 become much higher when water level at weir grow higher.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.3
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• pp.164-171
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• 2005

The aim of this study was to evaluate the load of nutrient from paddy fields. Water management practices that can reduce eutrophication and meet water quality requirements will also be addressed. Continuous monitoring from May to September in 2002 and 2003 was conducted for water quantification and qualification at the intensive paddy fields in Icheon, Gyunggi province of Korea. Water balance and concentration variation of nitrogen and phosphorus in the water were independently compared for water quality assessment at each rice cultivation period. Rice land preparation and transplanting periods usually marked the highest water demand when compared to other periods of cultivation. Overall, a greater net irrigation ratio was observed during the transplanting period in 2002 (92.3%) and 2003 (87.2%). The measured total N loads of precipitation, irrigation, drainage, and percolation during the rice cultivation period were 9.9, 41.6, 22.1, and $5.5kg\;ha^{-1}$ for 2002 and 15.8, 55.4, 17.3, and $7.5kg\;ha^{-1}$ for 2003, respectively. The measured total P loads of precipitation, irrigation, drainage, and percolation during the rice cultivation period were 2.1, 13.0, 3.6, and $1.8kg\;ha^{-1}$ for 2002 and 1.6, 15.0, 5.0, and $1.2kg\;ha^{-1}$ for 2003, respectively. Daily nutrient load followed the pattern of surface drainage water, but this pattern was changed by rainfall events. The nutrient load in drainage water depends on rainfall and surface drainage water amount from the paddy fields. Interestingly, the load of total N and total P output was smaller than the input load due to the natural infiltration that Occurred during the rice cultivation period. It is concluded that the paddy fields have a beneficial effect on the ecosystem and can reduce eutrophication in the water.

• Journal of Bio-Environment Control
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• v.6 no.4
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• pp.250-257
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• 1997

Stem diameter and shoot fresh weight of tomato grown in greenhouse were measured non-destructively at 10 minutes interval from 1 to 16 July, 1996 with displacement detector using strain gauges and with suspension-type load cell, respectively, and simultaneously were measured soil water potential, transpiration and solar radiation. Ample water was irrigated before experiment, and thereafter, irrigations were made on the next morning when visual symptoms of wilting appeared. Shoot fresh weight and stem diameter showed very similar patterns in diurnal changes which are characterized by predawn maximum and afternoon minimum and in long- term evolutions, suggesting that stem diameter shrinkage and expansion are closely related to plant water content and growth, respectively, Shoot weight and stem diameter reached minimum values a little later than the time on which transpiration showed maximum. The daily net gains of fresh weight(DG) and stem diameter(DI) showed significantly Positive correlations with solar radiation in those days on which plants were not water-stressed. However, Dl and DG on those days of water stress showed much lower values than expected from the relationships between solar radiation and them. Transpiration was much lower than the expected potential transpiration on 10 July, implying that plants were water-stressed. In this case water stress was not detected from visual symptom of wilting and/or soil water potential, but was able to be identified by the lower DI and DG than the expected. The maximum contraction of stem diameter(MC) and the maximum loss of fresh weight(ML) during daytime showed significantly positive correlations with solar radiation in those days on which plants were not water-stressed and were observed greater than expected from the relationships on severely water-stressed days. But mild water stress could not be discernable by ML and MC. It would be concluded that the daily net gains of fresh weight and/or stem diameter could be used as criteria for diagnosing the water status of tomato and for triggoring the onset of irrigation in automatic system.