Jeju Island is the highest rain-prone area in Korea that possesses affluent water resources, but future climate changes are predicted to further increase vulnerabilities as resultant of increasing of extreme events and creating spatial-temporal imbalance in water resources. Therefore, this study aimed to provide basic information to establish a proper water resources management plan by evaluating the effects of climate change on water resources using climate change scenario. Direct runoff ratio for 15 years (2000~2014) was analyzed to be 11∼32% (average of 23%), and average direct runoff ratio for the next 86 years (2015∼2100) was found as 28%, showing an increase of about 22% compared to the present average direct runoff ratio (23%). To assess the effects of climate change on long-term runoff, monthly runoff variation of future Gangjeong watershed was analyzed by dividing three time periods as follows: Present (2000∼2030), Future 1 (2031∼2070) and Future 2 (2071∼ 2100). The estimated results showed that average monthly runoff increases in the future and the highest runoff is shown by Future 2. Extreme values has been expected to occur more frequently in the future as compared to the present.

The purpose of this study was to estimate the growth promoting effects and improvement of antioxidant activity of the soybean sprouts treated with Chlorella sp. culture solution. The soybean sprout treated with 0.1% and 0.2% Chlorella sp. culture solution was significantly increased the length (more than 43.0%), the thickness (more than 0.5~0.7 mm), fresh weight (more than 2.9~3.7 g) compared to non-treated control in vitro. In organic soybean sprouts farm, the 0.2% chlorella culture solution applied to mass culture of soybean sprout and the fresh weight of soybean sprouts increased by more than 25% and the yield was very high as 598.33% compared to untreated control. In addition of sensory test, there is no fishy odor and better crunchy texture and nutty flavor for the treatment soybean sprouts compared to untreated soybean sprouts. Particularly, free-radical scavenging activity (DPPH) and superoxide dismutase activity (SOD) of the soybean sprouts were significantly increased more than 26.1% and 40.4%, respectively by treated with 0.1% and 0.2% Chlorella culture solution. Consequently, the treatment of chlorella culture solution to grow soybean sprouts is also promoting quality and antioxidant activity as well as promoting the growth of sprouts. Therefore, chlorella is considered to be worth as functional materials for high-quality sprouts grown.

We evaluated two herbal plants, basil (Ocimum basilicum) and lemon balm (Melissa officinalis), for their potential as repellent plants in the management of striped flea beetle (Phyllotreta striolata), in organic production of chinese cabbage. It was confirmed that striped flea beetle avoided these two herbal plants in olfactometer experiment. We conducted field experiment in which the suppressive effect of the two selected herbal plants and cruciferous crops preferred by striped flea beetle were evaluated through cultivating as inter crops and border crops, respectively. In inter-cropping experiment, unlike in vitro test, the density of striped flea beetle was low in basil- or mustard-intercropping cultivation plot, but high in lemon balm-intercropping cultivation plot. In border cropping experiment, the density of striped flea beetle on chinese cabbage in lemon balm or basil cultivation plot were approximately zero. As a result of this study, we think that border cropping of lemon balm or basil can be used to reduce preventively

The upland soils (56 samples) from organic farms in Gyeonggi-do (12 sites), Gangwon-do (8 sites), Chungcheong-do (14 sites), Gyeongsang-do (4 sites), Jeollado (18 sites) in Korea were collected and their physical and chemical properties were analyzed by RDA’s methods. In the results of physical property, the bulk density of soils averaged 1.14 Mg m-3 (surface soil), 1.38 Mg m-3 (subsoil), respectively. The porosity of them was 57%, 48%. Organically managed soil’s (OS) bulk density was lower than conventional soil’s but OS’s porosity was a little higher than conventionally managed soil in surface soil. The depth of plough layer in organically managed soils was 21.2 cm indicating that the organic farming had good effect on soil physical property. In the results of chemical property, the surface soil pH was 6.9 and the contents of organic matter (OM) was 26 g kg-1, available phosphate (Avail. P2O5) was 554 mg kg-1, exchangeable calcium (Exch. Ca) was 8.9 cmolc kg-1, exchangeable potassium (Exch. K) was 0.89 cmolc kg-1, exchangeable magnesium (Exch. Mg) was 2.0 cmolc kg-1. The subsoil pH was 6.8 and the contents of OM was 21 g kg-1, avail. P2O5 was 491 mg kg-1, exch. Ca was 7.9 cmolc kg-1, exch. K was 0.68 cmolc kg-1, exch. Mg was 1.8 cmolc kg-1. The nutrient accumulation emerged in organic farming. Compared to the optimum nutrient range for the conventional upland soils, the exceed rate of pH, OM, available phosphate, and exchangeable Ca, K, and Mg was 79, 52, 64, 84, 66% and 55%, respectively, which mainly resulted from the over-application of lime materials or livestock manure compost. With these results it is suggested thatorganic farm need to reduce the use of inputs, which make soil alkalification or nutrient accumulation. More study on effects of inputs on lowering soil pH from alkalification could help organically managed soil to be improved.

This study was carried out to identify the control effect of entomopathogenic microagent against Spodoptera exigua on organic chinese cabbage. In laboratory condition, insecticidal activity of 4 commercial BT pesticides against S. exigua were lower than 10% against second instar S. exigua. The insecticidal activity of entomopathogenic nematode were 33.3%, 83.3% and 100% at the concentration of 1×102, 3×102, 1×103 nematodes/ml, respectively. Mixture of BT and nematode showed growth inhibition against S. exigua larvae. S. exigua nucleopolyhedrovirus (SeNPV) of 105 PIBs/ml showed more than 70% insecticial activity. The yield of SeNPV was increased as in higher initial inoculation concentration of NPV, food supply, and growth temperature increased. In greenhouse experiment, the control value of BT and nematode mixture treatment was higher than BT and nematode treatment alone against S. exigua. In treatment of 107 PIBs/ml of SeNPV, S. exigua was controlled completely. In farm condition, mixture of microbial agent and organic agricultural material showed higher control value against lepidopteran pest including S. exigua than BT single treatment.

‘온토비’는 중, 북부 지역에서도 안정적인 월동이 가능하며 봄철 풋거름 수량이 많아 답리작 재배에 적합한 헤어리베치 품종을 육성할 목적으로 국립식량과학원에서 유전자원 ‘Ch4 (중국 도입)’에서 파생된 봄철 생육이 우세한 개체들을 선발 하여 계통육종법을 통해 개발되었다. 주요 특성은 개화기에 진한 녹엽색을 띠고, 줄기 모용 밀도가 높으며, 개화기는 전국 평균 5월 15일로써 대조품종인 ‘청풍보라’에 비해 5일 늦다. 월동율은 전국 평균 91%로써 대조품종 보다 2% 더 높은 경 향이었으며, 건물중수량은 ha당 평균 5.44톤으로써 대조품종 에 비해 17% 더 많았고, 질소함량은 ha당 평균 172 kg으로 써 대조품종에 비해 13% 더 증가하였다. ‘온토비’의 적응 지 역은 1월 최저 평균기온이 -15℃ 이상인 지역이면 전국 어느 곳에서나 재배가 가능하다(품종보호등록번호 제4748호).

In this study, we analyzed the characteristics of summer extreme rainfall over South Korea and their relationships with the synoptic and large-scale circulation anomalies during 1979-2014. Heavy rainfall (R90p) is related with the strong convection surrounded by dry zone over Korean peninsula and the moist air delivered from the convection area over Bay of Bengal-South China Sea-Philippine Sea. The upper-level anticyclonic flow with the low-level dipole of anticyclonic circulation in the Southeast and cyclonic circulation to the northwest of Korean peninsula are the main characteristics when the extreme rainfall occurs. The barotropic Rossby wave developed over the Korean peninsula transfers its energy farther downstream to the western coast of North America. It is also found that the dominant lowfrequency oscillation over the tropics (intraseasonal oscillation) play an important background role for the enhancement of extreme rainfall over South Korea.

We selected lactic acid bacteria to reduce cholesterol levels in vitro and in vivo. Among the 140 strains tested, a strain ID9201 was shown to reduce cholesterol in the spent medium over 30% and to increase cholesterol in cell pellet. A strain ID9201 isolated from breast milk-fed Korean infant feces was identified as Enterococcus faecium on the basis of morphological analysis, biochemical analysis (API kit), and 16S rDNA sequence analysis. A freeze-dried powder of the strain was fed to Sprague-Dawley(SD) rats with high cholesterol diet for 6 wk. In the control group fed cholesterol enriched diet without probiotics, the serum cholesterol increased by 1.9 times in comparison with the initial value. Among the test group, ID9201 group showed the lowest cholesterol increase, 1.5 times of initial serum cholesterol, as in the blank group fed normal diet without probiotics. Based on these data, we assumed that ID9201 inhibited intestinal absorption of dietary cholesterol.

나노기술은 현재 세계적으로 재료, 에너지, 화학, 바이오 등 각종분야에 적용되는 첨단 과학기술로 발전하고 있고 폭넓은 활용성과 경제적, 사회적 변화와 발전에 대한 기대감으로 연구개발이 활발히 진행되고 있다. 나노기술의 발전과 다양한 활용을 통해 나노제품이 증가함에 따라 나노물질의 생활환경 및 자연계, 인체로의 노출이 빈번해졌다. 최근 나노물질과 나노제품에 대한 보건 및 환경에 대한 위해성 문제가 꾸준히 제기되거나 소각, 폐수처리 시 나노물질이 완전히 제거되지않고 환경으로 배출되는 등 예상치 못한 부정적 영향이 제기됨에 따라 나노물질 및 나노물질이 함유된 폐기물에 대한 안전관리 방안 마련이 필요하게 되었다. 또한 최근에는 나노물질 자체의 위해성 문제와 함께 나노물질의 생산, 사용, 유통 과정과 나노제품을 사용하는 과정에서 발생되는 나노물질 함유 폐기물에 대한 관심이 증가하였다. 따라서 본 연구는 국내 나노물질 함유 폐기물의 발생 및 배출특성을 파악하고 조사된 국내 나노물질 유통량 현황자료를 바탕으로 조사대상 나노물질 중 SiO2 선정하였다. 국내 산업 업종별 SiO2 함유 가능성이 있는 폐기물을 발생하는 업체를 선정하고 총 12개의 시료를 채취하였다. 채취된 시료는 폐기물 공정시험기준, 토양오염 공정시험기준에 따라 유해물질의 용출 및 함량 분석을 하였고 XRD, XRF를 아용한 화학물질의 함량을 분석하였다. 또한 입도분석 및 전자현미경(TEM) 분석을 통해 나노물질 함유 폐기물이 일반폐기물과 다른 특성을 조사하였다.

현행 폐기물관리법 시행규칙에 광재류의 재활용 기준 및 구체적인 재활용방법은 있으나 배출자(또는 재활용하려는 자)의 재활용용도 및 방법확대에 대해서는 제한적이며, 특히 성토재, 도로기층재 등 토양에 직접 사용할 경우 환경 및 건강에 미치는 영향, 매립시 광재류의 유해특성, 유용자원의 회수 등에 대한 구체적인 내용은 미흡하다. 또한, 비철금속공정별 발생하는 분진, 슬러지, 광재류 등의 특성에 따른 재활용 방법, 환경에 직접 재활용할 경우 지하수, 토양, 지표수 등에 미치는 영향을 평가하는 방법을 정립하는 것이 필요하다. 따라서 본 연구에서는 비철 광재류 재활용확대 및 환경오염방지를 위해 중금속 함량 및 용출특성을 조사하였다. 본 연구에서는 천연광물을 원료로 수입･제조･사용한 후 발생하는 비철 광재류 5종(망간, 납, 알루미늄, 니켈, 구리)에 대한 중금속 함량 및 용출 농도를 조사하였고 이에 따른 비철광재류의 재활용을 위한 기초 조사로 중금속류 특성을 조사하였다. 비철 광재류의 용출농도는 폐기물공정시험법에 따라 전처리 및 기기분석을 하였다. 함량농도는 EPA 3051법에 따라 전처리 후 기기분석을 하였고, 불소와 시안 등은 토양오염공정시험방법에 따라 측정하였다.

This study is, when we pour the concrete, doing bonding shear performance evaluation to search the influence about an adhesive interface by a generated cold joint with a retardation time. In conclusion, this experiment shows that the higher a compressive strength of the concrete is, the higher a reduction ratio of the bonding shear strength is, and the instance of a none agitation and a compaction with 15 minutes of a retardation time are the lowest influence in a whole of the results; each of the reduction ratio of the bonding shear strength is approximately 4.5%.

Since deteriorated bridge increases each year in Korea and Japan, the study was conducted for the direction of improving reinforcement and conservation for RC deck t because common facts in damaged RC deck is that crack was found in direction 1 and direction 2 that the crack leads to compound damage.

12 tests are performed to analyze the specific performance and pullout strength of an anchor bolt against which has a greater contact area with the concrete. In the case of unsymmetric nut, the pullout average strength at the side registers over 14% stronger in comparison with normal bolts.

This study presents the results of an experimental program carried out for estimating the variation of the flexural rigidity of reinforced concrete beams with different shear span-to-depth ratios. The specimens are designed to have identical sectional dimension, tension and compression reinforcement ratios, and material properties, except shear span-to-depth ratio. Experimental results showed that the flexural rigidity of reinforced concrete beams was affected by the shear span-to-depth ratio of specimens.