• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.4
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• pp.165-170
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• 2011

The ambient concentrations of nitrogen dioxide ($NO_2$) at 65 forest areas were measured every month using passive diffusive samplers from 2002 to 2009 and were compared to those at urban areas in order to investigate the characteristics of temporal and spatial distributions of $NO_2$ from the forest and urban areas. The annually averaged concentrations of $NO_2$ gradually decreased for both areas. The average concentration of $NO_2$ in the forest areas was 8.0 ppb, which was lower than that in the urban areas (i.e., 19.4 ppb) and the ecological standard level of the European Union (i.e., 14.6 ppb). The monthly average of $NO_2$ concentration depicted seasonal variations particularly in the urban areas, showing higher concentration in winter and lower concentration in summer. Strong locality of $NO_2$ concentration distribution illustrates that the locations near the metropolitan areas (e.g., Gyeonggi and Chungnam provinces) had the highest concentration during the measurement period. A significant positive correlation between $NO_x$ emissions and $NO_2$ concentration was observed, suggesting that the magnitude and proximity to sources of atmospheric nitrogen oxides would be important controlling factors.

• Journal of the Korean association of regional geographers
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• v.13 no.6
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• pp.609-622
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• 2007

This paper examines the lava tubes designated as a natural monument in Jeju Island, and then makes the several suggestions for conserving and managing them. The cave entrances should be scientifically and strictly managed to prevent the deterioration, and to preserve the interior ecosystem, of the lava tubes. The land use and vegetation of the ground surface over the lava tubes should be also systematically managed; the destroyed sand dunes must be recovered for the development of speleothem in the lava tubes, and the plants with deep roots must be removed for the prevention of ceiling collapse. The provincial authorities should manage the ground surface over the lava tubes as a public land to remove the factors threatening the stability of the lava tubes. Since the roads crossing the ground surface are likely to cause the collapse of the lava tubes, new roads bypassing the caves need to be constructed, and warning signs should be also installed at the traverse points. A monitoring system on the cultural properties protection area over the lava tubes could be effectively established by encouraging residents to participate the conservation program of lava tubes. Since the falling blocks from ceilings have been usually observed in the lava tubes, it is urgent to examine their stability. In particular, the dangerous sections must be continuously monitored for taking a quick measure against the collapse. The air environments of lava tubes need to be scientifically analyzed based upon the long-term observations. The lighting equipments must be improved to minimize the green pollution in the lava tubes open to the public. The numbers of visitors should be also controlled to prevent the destruction and contamination of lava tubes caused by a large number of visitors.

• Journal of the Korean earth science society
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• v.23 no.5
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• pp.424-435
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• 2002

This study analyzes the surface ozone and meteorological data in Daegu for a period from 1997 to 1999. It also investigates the meteorological characteristics of high ozone episodes. For this study the high ozone episode has been defined as a daily maximum ozone concentration higher than 100ppb in at least one station among six air quality monitoring stations in Daegu, Korea. The frequency of episodes is 13 days. The frequency is the highest in May and September. The average value of daily maximum ozone concentration is 81.6ppb, and 8-hour average ozone concentration is 58.6ppb for the high episodes. This shows that ozone pollution is continuous and wide-ranging in Daegu. The daily maximum ozone concentration is positively correlated to solar radiation and daily maximum temperature, but negatively correlated to relative humidity, wind speed and cloud amount. The maximal correlation coefficient to solar radiation is 0.45. The differences between high ozone episode day's daily mean meteorological value and monthly mean value are +1.58hPa for sea level pressure, +3.45${\circ}$C for maximum temperature, -5.69% for relative humidity, -0.46ms$^{-1}$ for wind speed, -1.79 for cloud amount, and +3.97MJm$^{-2}$ for solar radiation, respectively. This shows that strong solar radiation, low wind speed and no precipitation between 0700${\sim}$1100LST are favorite conditions for high ozone episodes. It is related to the morning stagnant condition.

• Journal of Appropriate Technology
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• v.6 no.1
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• pp.37-44
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• 2020

Medical waste is any kind of waste that contains infectious material and recommended not to be transferred for infection control. As a means of disposal, incineration has better points than dumping or landfill in the quantity reduction, odorless and nonhazardous. However, open burning and incineration of health care wastes under bad circumstances, can result in the emission of environmental pollutants to air. A burial of biological waste brings pollution of soil and water. Most of sub divisional hospitals in Fiji transfer their medical wastes to divisional hospitals for incineration. In 2011, 62,518 kg of medical waste was incinerated in the three divisional hospitals. However, some medical wastes are considered as general waste and burnt or sent to landfill site, some are buried on site in some sub-divisional hospitals. In this regards, urgent education is necessary for awareness promotion to relevant personnel in medical waste treatment. On site incineration using small scale incinerator is more recommended than transportation of medical wastes treatment in Fiji. Moreover, remotely controllable and fixable small scale of incinerator is more desirable in sub-divisional hospitals. It is recommended that Fiji government to set up a legal framework for medical waste management (MWM), to develop specific guidelines for MWM, to set up a training system for MWM to ensure that all relevant personnel are trained, to develop a monitoring and supervision system for MWM, to clarify the future financing of MWM activities, and to improve the MWM infrastructure.

• Journal of Environmental Health Sciences
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• v.49 no.2
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• pp.108-117
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• 2023

Background: When particles are absorbed into the human body, they penetrate deep into the lungs and interact with the tissues of the body. Heavy metals in PM_2.5 can cause various diseases. The main source of PM_2.5 emissions in South Korea's atmosphere has been surveyed to be places of business. Objectives: The concentration of heavy metals in PM_2.5 near the Ulsan Industrial Complex was measured and a health risk assessment was performed for residents near the industrial complex for exposure to heavy metals in PM_2.5. Methods: Concentrations of heavy metals in PM_2.5 were measured at four measurement sites (Ulsan, Mipo, Onsan, Maegok) near the industrial complexes. Heavy metals were analyzed according to the Air Pollution Monitoring Network Installation and Operation Guidelines presented by the National Institute of Environmental Research. Among them, only five substances (Mn, Ni, As, Cd, Cr⁶⁺) were targeted. The risk assessment was conducted on inhalation exposure for five age groups, and the excess cancer risk and hazard quotient were calculated. Results: In the risk assessment of exposure to heavy metals in PM_2.5, As, Cd, and Cr⁶⁺ exceeded the risk tolerance standard of 10^-6 for carcinogenic hazards. The highest hazard levels were observed in Onsan and Mipo industrial complexes. In the case of non-carcinogenic hazards, Mn was identified as exceeding the hazard tolerance of 1, and it showed the highest hazard in the Ulsan Industrial Complex. Conclusions: This study presented a detailed health risk from exposure to heavy metals in PM_2.5 by industrial complexes located in Ulsan among five age groups. It is expected to be utilized as the basis for preparing damage control and industrial emission reduction measures against PM_2.5 exposure at the Ulsan Industrial Complex.

• Journal of Korea Water Resources Association
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• v.53 no.10
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• pp.845-859
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• 2020

Climate change and recent heat waves have drawn public attention toward other environmental issues, such as water pollution in the form of algal blooms, chemical leaks, and oil spills. Water pollution by the leakage of chemicals may severely affect human health as well as contaminate the air, water, and soil and cause discoloration or death of crops that come in contact with these chemicals. Chemicals that may spill into water streams are often colorless and water-soluble, which makes it difficult to determine whether the water is polluted using the naked eye. When a chemical spill occurs, it is usually detected through a simple contact detection device by installing sensors at locations where leakage is likely to occur. The drawback with the approach using contact detection sensors is that it relies heavily on the skill of field workers. Moreover, these sensors are installed at a limited number of locations, so spill detection is not possible in areas where they are not installed. Recently hyperspectral images have been used to identify land cover and vegetation and to determine water quality by analyzing the inherent spectral characteristics of these materials. While hyperspectral sensors can potentially be used to detect chemical substances, there is currently a lack of research on the detection of chemicals in water streams using hyperspectral sensors. Therefore, this study utilized remote sensing techniques and the latest sensor technology to overcome the limitations of contact detection technology in detecting the leakage of hazardous chemical into aquatic systems. In this study, we aimed to determine whether 18 types of hazardous chemicals could be individually classified using hyperspectral image. To this end, we obtained hyperspectral images of each chemical to establish a spectral library. We expect that future studies will expand the spectral library database for hazardous chemicals and that verification of its application in water streams will be conducted so that it can be applied to real-time monitoring to facilitate rapid detection and response when a chemical spill has occurred.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.2
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• pp.41-63
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• 2022

The purpose of this study is to secure objective and precise data through ecosystem monitoring, to reveal ecological characteristics through comparison and analysis with past survey data, and to accumulate basic data for diagnosing the current situation and predicting changes in the ecosystem. The target site is the 'Quercus mongolica forest on the Buksa-myeon of Namsan', which was designated as an Ecological Landscape Conservation Area (ELCA) of Seoul in July 2006. The research contents are analysis of soil environment change (1986~2016), change of actual vegetation (1978~2016), and change of plant community structure (1994~2016). A total of 8 fixed surveys (400~1,200m²) were established in 1994 and 2000. Analysis items are importance value, species and population, and Shannon's species diversity. The soil environment of Namsan is acidic (pH 4.40 in 2016), which is expected to have a negative impact on tree growth and vegetation structure due to its low capacity for exchangeable cations. Quercus mongolica forest in Namsan is mainly distributed on the northern slopes. The actual vegetation area changed from 49.4% in 1978 → 80.7% in 1986 → 82.4% in 2000 → 88.3% in 2005 → 88.3% in 2009 → 70.3% in 2016. In 2016, the forest decreased by 18% compared to 2009. While there was increased growth of Quercus mongolica in the tree layer from 2009 to 2016, the overall decline in vegetation area was due to logging and fumigation management following the spread of oak wilt in 2012. As for the changes in the plant community structure, Quercus mongolica of the tree layer was damaged by oak wilt, and the potential vegetation that can form the next generation was ambiguous. In the subtree layer, the force of urbanization tree species such as Styrax japonicus, Sorbus alnifolia, and Acer palmatum. was maintained or increased. In the shrub layer, the number of trees and species increased significantly due to the open tree crown, and accordingly, the species diversity of Shannon for woody plants also increased. In Quercus mongolica forest of Namsan, various ecological changes are occurring due to the effects of urban environments such as air pollution and acid rain, the limitation of Quercus mongolica pure forest due to oak wilt, and the introduction of exotic species, thus, it is necessary to establish a management plan through continuous monitoring.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.578-583
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• 2010

Acid rain and its problem to environment such as acid precipitation and environmental problems related to the air pollution in East Asia has been emerging. To evaluate the acidity and chemical characteristics of rainwater precipitated in western Korea, Suwon and Taean, its pH and ion concentrations were investigated during farming season (April to November) in 2009. Also, ion composition and cation-affected neutralization were determined to evaluate the contribution of cations on the acidity of rainwater. Ion and electrical conductivity between the measured and the estimated showed high correlation. The $Na^+$ in rainwater was the main cation followed by ${NH_4}^+>Ca^{2+}>H^+>Mg^{2+}>K^+$. Sum of $Na^+$ and ${NH_4}^+$ contents was over 65% of total cations contents. In the case of anions, the concentration was in order of ${SO_4}^{2-}>{NO_3}^->Cl^-$. The ${SO_4}^{2-}$ among anions in rainwater composed about 61%, which showed on average 130.2 ${\mu}eq\;L^{-1}$ and 121.3 ${\mu}eq\;L^{-1}$ during monitoring at Suwon and Taean, respectively. Also, 89.6 and 88.6% of soluble sulfate in rainwater at Suwon and Taean area was NSS-${SO_4}^{2-}$ (Non-Sea Salt sulfate). Especially, ${NH_4}^+$ and $Ca^{2+}$ contributed greatly in neutralizing the acid rain in dry season. Total nitrogen content flowed into soil from rain was around 1~2 kg $ha^{-1}$ in each month, but in July at Suwon, it reached 6 kg $ha^{-1}$ due to heavy rain (over 7.3 mm).