The characteristics of meteorological conditions related to changes in atmospheric environment on Jeju Island were investigated during recent years (2010-2012). This analysis was performed using the hourly observed data of meteorological variables (air temperature, wind speed and direction) and air pollutants (O3, PM10, SO2, NO2, and CO). Out of 5 pollutants, O3 and PM10 concentrations have frequently exceeded national environmental standards in the study area during the study period, with relatively higher concentrations than the others. The concentrations of O3 and PM10 in 2010 and 2011 were somewhat higher than those in 2012, and their highest concentrations were mostly observed in spring followed by fall. Nighttime O3 concentrations (with relatively high concentration levels) were almost similar to its daytime concentrations, due to less O3 titration by very low NO concentrations in the target area and in part to O3 increase resulting from atmospheric transport processes. The transport effect related to the concentration variations of O3 and PM10 was also clarified in correlation between these pollutants and meteorological variables, e.g. the high exceedance frequency of concentration criteria with strong wind speed and the high concentrations with the westerly/northwesterly winds (e.g., transport from the polluted regions of China). The overall results of this study suggest that the changes in atmospheric environment in the study area were likely to be caused by the transport effect (horizontal and vertical) due to the meteorological conditions rather than the contribution of local emission sources.

함양 지체시간은 강우로부터 지표면을 지나 지하수면으로 도달하는 침투수의 통로 역할을 하는 비포화대를 통과할 때 발생하는 시간지연을 의미한다. 함양 지체시간을 직접적으로 측정하는 것은 불가능하기 때문에 본 연구는 고도와의 단순회귀분석을 이용하여 지체시간에 대한 경험식을 유도하였다. 이를 위하여 제주도 내에 4개의 유역(한천, 강정천, 외도천, 천미천)을 선정하여 총 18개의 관측지점에 대한 지체시간을 산정하였다. 또한 제안된 회귀식을 검증하기 위하여 선형 저수지 이론으로부터 유도된 방정식을 적용하여 구한 지체시간과 본 연구에서 유도된 경험식으로부터 산정된 지체시간을 이용하여 각각 산정한 지하수 함양량을 비교한 결과 상관성이 높은 것을 확인할 수 있었다. 따라서 본 연구에서 유도한 경험식을 이용하여 SWAT모형의 지체시간 매개변수에 적용할 경우 지하수 함양의 공간적 지연효과를 잘 반영할 것으로 판단된다.

This study was carried out to investigate the vegetation and habitat environment of Sageretia thea which isdistributed in Jeju island, Korea. Sageretia thea were mainly distributed to the west area in Jeju island. Soil pH andEC of Sageretia thea habitat were 5.8 and 0.34dS•m−1. The contents of organic matter, available phosphate, exchangeablepotassium, exchangeable sodium, exchangeable magnesium and exchangeable calcium were 15.27%, 13.6㎎㎏−1,0.27cmol+㎏−1, 1.3cmol+㎏−1, 1.7cmol+㎏−1, 4.9cmol+㎏−1, respectively. Thirty one taxa including 25 families, 31 genus, 27species and 4 varieties were identified surrounding Sageretia thea habitat. Specific plant species were 1 taxon in III grade, 1taxon in I grade and 3 taxa in I grade.

Due to tidal force, it is very difficult to estimate the hydraulic parameters of high permeable aquifer near coastal area in Jeju Island. Therefore, to eliminate the impact of tidal force from groundwater level and estimate the hydraulic properties, tidal response technique has been mainly studied. In this study we have extracted 38 tidal constituents from groundwater level and harmonic constants including frequency, amplitude, and phase of each constituent using T_TIDE subroutine which is used to estimate oceanic tidal constituents, and then we have estimated hydraulic diffusivity associated with amplitude attenuation factor(that is the ratio of groundwater level amplitude to sea level amplitude for each tidal constituent) and phase lag(that is phase difference between groundwater level and sea level for each constituent). Also using harmonic constants for each constituent, we made the sinusoidal wave and then we constructed the synthesized wave which linearly combined sinusoidal wave. Finally, we could get residuals(net groundwater level) which was excluded most of tidal influences by eliminating synthesized wave from raw groundwater level. As a result of comparing statistics for synthesized level and net groundwater level, we found that the statistics for net groundwater level was more insignificant than those of synthesized wave. Moreover, in case of coastal aquifer which the impact of tidal force is even more than those of other environmental factors such as rainfall and groundwater yield, it is possible to predict groundwater level using synthesized wave and regression analysis of residuals.

Quantitative assessment of groundwater level change under extreme event is important since groundwater system is directly affected by drought. Substantially, groundwater level fluctuation reveals to be delayed from several hours to few months after raining according to the aquifer characteristics. Groundwater system in Jeju Island would be also affected by drought and almost all regions were suffered from a severe drought during summer season (July to September) in 2013. To estimate the effect of precipitation to groundwater system, monthly mean groundwater levels in 2013 compared to those in the past from 48 monitoring wells belong to be largely affected by rainfall(Dr) over Jeju Island were analyzed. Mean groundwater levels during summer season recorded 100 mm lowered of precipitation compared to the past 30 years became decreased to range from 2.63 m to 5.42 m in southern region compared to the past and continued to December. These decreasing trends are also found in western(from –1.21 m to –4.06 m), eastern(-0.91 m to –3.24 m), and northern region(from 0.58 m to –4.02 m), respectively. Moreover, the response of groundwater level from drought turned out to be –3.80 m in August after delaying about one month. Therefore, severe drought in 2013 played an important role on groundwater system in Jeju Island and the effect of drought for groundwater level fluctuation was higher in southern region than other ones according to the regional difference of precipitation decrease.

Temporal variation of groundwater levels in Jeju Island reveals time-delaying and dispersive process of recharge, mainly caused by the hydrogeological feature that thickness of the unsaturated zone is highly variable. Most groundwater flow models have limitations on delineating temporal variation of recharge, although it is a major component of the groundwater flow system. A new mathematical model was developed to generate time series of recharge from precipitation data. The model uses a convolution technique to simulate the time-delaying and dispersive process of recharge. The vertical velocity and the dispersivity are two parameters determining the time series of recharge for a given thickness of the unsaturated zone. The model determines two parameters by correlating the generated recharge time series with measured groundwater levels. The model was applied to observation wells of Jeju Island, and revealed distinctive variations of recharge depending on location of wells. The suggested model demonstrated capability of the convolution method in dealing with recharge undergoing the time-delaying and dispersive process. Therefore, it can be used in many groundwater flow models for generating a time series of recharge.

In this work, the delay time for groundwater recharge was estimated by comparing simulated recharges by means of SWAT(Soil and Water Assessment Tool) model and WTF(Water Table Fluctuation) method. The delay time for groundwater recharge means that the time when the water from rainfall travelled through vadose zone just after getting out of soil zone bottom. As measuring this delay time is almost impossible, we used to compare the estimated values from modeling(SWAT) and analytic method(WTF). The test site is Hancheon watershed which has 8 groundwater measurement stations. The results show that the altitude has a linear relationship with the estimated delay time values. To validate these results, we conducted corelation analysis between transformed groundwater levels and observed ones. The results showed that computed groundwater levels have good corelation(R2=0.97, 0.87, respectively). The estimated delay time would be used for the groundwater behaviour characteristics in vadose zone. As recharge rates vary according to the height, the delay time is thought to be an import variable for the proper groundwater recharge estimation.

The rainfall-runoff characteristics in Jeju Island significantly differ from those in inland, due to highly permeable geologic features driven by volcanic island. Streams are usually sustained in the dry conditions and thereby the rainfall-runoff characteristics changes in terms of initiating stream discharge and its types, depending highly on the antecedent precipitation. Among various the rainfall-runoff characteristics, lag time mainly used for flood warning system in river and direct runoff ratio for determining water budget to estimate groundwater recharge quantity are practically crucial. They are expected to vary accordingly with the given antecedent precipitation. This study assessed the lag time in the measured hydrograph and direct runoff ratio, which are especially in the upstream watershed having the outlet as 2nd Dongsan bridge of Han stream, Jeju, based upon several typhoon events such as Khanun, Bolaven, Tembin, Sanba as well as a specific heavy rainfall event in August 23, 2012. As results, considering that the lag time changed a bit over the rainfall events, the averaged lag time without antecedent precipitation was around 1.5 hour, but it became increased with antecedent precipitation. Though the direct run-off ratio showed similar percentages (i.e., 23%)without antecedent precipitation, it was substantially increased up to around 45% when antecedent precipitation existed. In addition, the direct run-off ration without antecedent precipitation was also very high (43.8%), especially when there was extremely heavy rainfall event in the more than five hundreds return period such as typhoon Sanba.

Storm surge height in the coastal area of Jeju Island was examined using the Princeton Ocean Model(POM) with a sigma coordinate system. Amongst the typhoons that had affected to Jeju Island for six years(1987 to 2003), the eight typhoons(Maemi, Rusa, Prapiroon, Olga, Yanni, Janis, Gladys and Thelma) were found to bring relatively huge damage . The storm surge height of these typhoons simulated in Jeju harbour and Seogwipo harbour corresponded relatively well with the observed value. The occurrence time of the storm surge height was different, but mostly, it was a little later than the observed time. Jeju harbour showed a higher storm surge height than Seogwipo harbour, and the storm surge height didn't exceed 1m in both of Jeju harbour and Seogwipo harbour. Maemi out of the eight typhoons showed the maximum storm surge height(77.97 cm) in Jeju harbour, and Janis showed the lowest storm surge height(5.3 cm) in Seogwipo harbour.

The number concentrations, the mass concentrations and the elemental concentrations of PM10 have measured at Gosan site in Jeju, Korea, from March 2010 to December 2010. And the correlation and the factor analysis for the number, the mass and the elemental concentrations of PM10 are performed to identify their relationships and sources. The average PM10 number concentration is observed 246 particles/㎝3(35.7∼1,017 particles/㎝3) and the average PM10 mass concentration is shown 50.1 ㎍/㎥(16.7∼441.4 ㎍/㎥) during this experimental period. The number concentrations are significantly decreased with increasing particle size, hence the concentrations for the smaller particles less than 2.5 ㎛(PM2.5) are contributed 99.6% to the total PM10 number concentrations. The highest concentration of the 20 elements in PM10 determined in this study is shown by S with a mean value of 1,497 ng/㎥ and the lowest concentration of them is found by Cd with a mean value of 0.57 ng/㎥. The elements in PM10 are evidently classified into two group based on their concentrations: In group 1, including S>Na> Al>Fe>Ca>Mg>K, the elemental mean concentrations are higher than several hundred ng/㎥, on the other hand, the concentrations are lower than several ten ng/㎥ in group 2, including Zn>Mn>Ni>Ti>Cr>Co>Cu>Mo>Sr>Ba>V >Cd. The size-separated number concentrations are shown positively correlated with the mass concentrations in overall size ranges, although their correlation coefficients, which are monotonously increased or decreased with size range, are not high. The concentrations of the elements in group 1 are shown highly correlated with the mass concentrations, but the concentrations in group 2 are shown hardly correlated with the mass concentrations. The elements originated from natural sources have been predominantly related to the mass concentrations while the elements from anthropogenic sources have mainly affected on the number concentrations of PM10.

This study is carried out to propose an empirical equation which can promptly predict the aircraft noise level at a specific point (a receptor) near Jeju international airport by using the information of the flight path data. For this purpose, Analyses of multiple linear regression with the slant distances (SD) calculated from the gate analyses of the flight path data, aircraft noise certification levels with unit of EPNL(effective perceived noise level) and noise levels measured at receptors are performed by SPSS package. From these regression analyses for approach and departure of aircraft, we can propose empirical equations which is statistically significant. The noise levels predicted by these empirical equations are highly correlated the measured data.

The occurrence trends and moleculargenetic characteristics of noroviruses detected from gastroenteritis patients in Jeju from 2008 to 2010 were investigated. In addition, the norovirus contamination and its characteristics of groundwaters in Jeju were examined. The incidence caused by norovirus in viral gastroenteritis patients has increased every year and was higher in male than in female. The patients caused by norovirus occurred throughout all months. The incidences started to increase from November, were very high from December to February, started to decrease from March, and were very low from June to September. The patients caused by norovirus occurred throughout all ages, however, the infants below 5 years were the most susceptible to norovirus infection and the age group from teens to forties were the most insensitive to norovirus infection. The sequencing analysis showed that 18 genotypes (8 genogroup I (GI) and 10 genogroup II (GII)) were detected, the incidences caused by GI and GII were 11.5% and 88.5%, respectively, and predominant genotype was GII-4 (70.5%), which was the major genotype giving rise to norovirus incidences in Jeju, together with GII-3 (6.1%) and GI-4 (4.1%). Among 20 groundwaters sampled at 9 wells (4 non-drinking water wells and 5 drinking water wells), noroviruses were detected from 2 groundwaters sampled at one non-drinking water well and their genotypes were GI-5 and GI-8.

Jeju Special Self-Governing Province has the natural assets resulting in UNESCO World Biosphere Reserve, World Heritage Listed and World Geopark Certification, so the principle of 'Conservation First Development Later' has been set up for the vision of environmental policy to preserve these assets. This case study has been carried out to investigate the realization of the principle of 'Conservation First Development Later' for the development projects performed environmental impact assessment from 1994 to 2012 in Jeju Province, using geographic information systems(GIS). The Jeju Province has its own ordinance to consult and operate an environmental impact assessment(EIA) system. In particular, the conservation area, such as, Absolute/Relative Conservation Area and Underground Water, Ecosystem and View Conservation Zone, has been assigned and managed specially to conserve the natural environment. The 179 projects has been performed EIA for last 18 years in Jeju Province, and then the Absolute Conservation Area has been included in 22 projects and the Relative Conservation Area has been included in 34 projects. However, the 2 projects only have included the Absolute Conservation Area for 7 years after 2005. This result suggests that the application of the principle for the Absolute Conservation Area is strengthened gradually. On the other hand, the 17 projects and the 24 projects have included the Underground Water Conservation Zone assigned grade 1 and 2, respectively, and the number has been increasing after 2004. The results show that it needs to strengthen the application of the principle for this Zone. And the Ecosystem Conservation Zone assigned grade 1 and 2 have been included in 1 project and 9 projects, respectively. It is considered from this result that the principle is realized successfully for the Ecosystem Conservation Zone. In addition, it could be known that the principle is applied well for the View Conservation Zone, in this study.

본 연구는 최근 관광 및 학술적으로 중요성과 가치를 인정받고 있는 천연기념물 제374호 제주 평대리 비자나무 숲을 대상으로 방문객 인식, 숲의 자원과 시설 수준에 대한 기대도, 만족도, 기대일치도를 조사하여 개선방안을 마련하고자 하였다. 첫째, 비자나무 숲 방문객은 남성(39.8%)보다 여성(60.2%), 30대 이상의 중장년층(85%), 대졸이상의 고학력자(58.7%), 주부(21.8%)와 회사원(28.2%), 수도권지역 거주민(47.9%), 자동차(74.8%)를 타고 오는 방문객이 많은 비중을 차지하였으며, 가족과 함께 자연경관 감상(46.6%), 가족과 여가(21.4%), 휴식을 위해(19.9%), 처음 방문하는 경우(69.4%)가 많았다. 둘째, 비자나무 숲의 천연기념물 지정사실(67.0%), 관련 전설 및 유래(68.9%), 비자나무 열매 효능 등을 모르는 경우(52.0%)가 많았으나, 방문 후 천연기념물로서의 가치를 인식하고 있었으며 비자나무 숲 방문으로 정신적, 신체적 피로가 회복되었다(99%)고 응답하였다. 셋째, 전체적으로 비자나무 숲에 대해 높은 만족을 보이고 있었다. 경관적요소, 식물적요소, 편의시설, 유지관리는 기대보다 만족도가 높은 요소였으며 대체적으로 기대감이 낮은 것을 확인 할 수 있었다. 넷째, 경관적요소와 식물적요소에 대한 기대일치도(각3.88)가 가장 높게 나타났으며, 이 두 요소는 기대도와 만족도가 모두 높았다. 또 편의시설의 기대일치도(3.36)는 낮게 나타났다. 다섯째, 식물적 요소에 대한 기대일치가 높을수록(상관계수 0.196) 전체만족도가 높아지는 것으로 평가되었다. 따라서 천연기념물로서의 가치를 잃지 않도록 지속적으로 비자나무의 생육상태를 체크하고 원시림의 상태로 비자나무 숲을 보존하는 것이 가장 중요하겠다.