• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.476-476
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• 2022

농업용수는 전통적 기능으로 농업용수 그 자체로서의 기능과 시대적 요구에 따른 지역용수로서의 기능을 가진다. 농업용수 그 자체의 기능으로 가장 중요한 것은 관개용수이며, 논, 밭관개, 하우스 시설농업에의 용수공급이다. 농업용수의 실 수요량 측면에서는 논용수가 전체용수 수요량의 60.1%로 가장 많은 양을 차지하고 있으며, 다음으로는 밭용수가 18.6%, 그 외 생활용수, 공업용수, 환경용수, 축산용수 등으로 이용되고 있다. 농업용수 수요 측면에서 논용수의 비중이 가장 높게 나타나기 때문에 본 연구에서는 농업용수 공급에 따라 농업용저수지-관개수로-논에 이르는 공급단계별 수질변화를 분석하였다. 본 연구는 경기, 충남 권역의 오염도가 높은 3개 농업용저수지를 대상으로 하였으며, 농업용수를 본격적으로 공급하는 5월부터 관개가 종료되는 10월까지 농업용저수지와 관개수로, 논을 대상으로 수온, TOC, Chl-a 등 10개 항목을 분석하여 나타내었다. 연구기간동안 수온의 변화는 18.6~34.6 ℃로서 관개수로에 가장 낮고, 논에서 가장 높은 값을 보여 주었으며, 공급단계별 평균 수온은 저수지(R) 27.6 ℃, 관개수로(C) 26.4 ℃, 논(P) 28.4 ℃로 논에서 수온증가가 나타났다. pH는 7.4~9.7의 범위로 저수지에서 최고값, 논에서 최저값을 보였으며, 공급단계별 평균값은 R 9.1, C 8.3, P 8.0으로 저수지, 수로, 논으로 이동하면서 감소하였다. 전기전도도(EC)는 저수지 수질오염도에 따라 다양하게 나타났으며, 공급단계별 평균값은 R 706.3 uS/cm, C 585.5 uS/cm, P 771.2 uS/cm로 논에서 가장 높은 값으로 보였으며, 이는 논에서 추가적인 영양분 공급에 의한 것으로 보였다. 평균 용존산소량(DO)은 R 6.3, C 4.0, P 4.5로 저수지에서 가장 높고, 수로에서 가장 낮게 나타났다. 유기물 지표인 COD와 TOC의 변화를 보면 평균 COD R 21.7 mg/L, C 14.5 mg/L, P 22.7 mg/L, 평균 TOC R 11.2 mg/L, C 8.5 mg/L, P 12.3 mg/L로 두 항목 모두 논에서 가장 높은 값을, 수로에서 가장 낮은 값을 나타내었다. 반면 엽록소 a 평균 농도는 R 128.4 mg/m³, C 54.3 mg/m³, P 31.7 mg/m³로 저수지의 내부생산으로 다량 발생한 조류가 수로와 논으로 이동하면서 급격하게 감소하여 나타났다. 이는 저수지와 논의 유기물 성상이 다름을 보여준다. 영양염류인 총인(TP)의 평균값 변화를 보면 R 0.302 mg/L, C 0.374 mg/L, P 0.384 mg/L로, 저수지에서 수로, 논으로 이동하면서 점차 증가하여 나타났다. 이는 농업용저수지에서 수로, 논으로 관개용수가 이동하면서 오염수 유입 또는 비료 등의 투입이 이루어진 결과로 판단된다. 이와 같이, 농업용저수지의 수질이 논에 그대로 유지되어 유입되지 않고 공급단계에 따라 변화하고 있으므로 항목별 수질 변화 특성을 이해한 후 농업용수 수질관리가 이루어 져야 할 것이다.

• Economic and Environmental Geology
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• v.38 no.5 s.174
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• pp.525-534
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• 2005

Adsorption experiments for As(V) and As(III) onto the surfaces of aerobic Pseudomonas aeruginosa, which can be readily isolated from natural media, were conducted under nutrient-absent conditions. While a small amount of As(III) was adsorbed on the bacterial cell surfaces, As(V) was not effectively removed from the solution through adsorption. The result was likely due to the electrostatic repulsion between anionic compounds of aqueous As(V) and cell surfaces of f aeruginosa. However, the bacteria forming biofilm reduced a large amount of aqueous As(V) to As(III), which indicated that microorganisms in most oligotrophic, natural geologic settings can mediate the behavior of aqueous As. Biobarriers designed to remove the various heavy metals in contaminant plume may practically lead to the enhancement of toxicity and mobility of As.

• Journal of Radiation Protection and Research
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• v.23 no.1
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• pp.25-32
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• 1998

Tritium is released into the environment as various form but HTO is most relevant to the incorporation of tritium into living organisms and to the formation of OBT. Tritiated compounds may be transported to humans via several tropic levels. Retention times of organically bound tritium in organisms are considerably longer than those of tritiated water, which has significant consequences on exposure dose estimation. It is rather difficult to predict the amount of OBT produced by the photosynthetic process of plants because it may be influenced by a multitude of environmental factors and plant parameters. Tritiated organic matters are classified as the exchangeable or nonexchangeable bound tritium according to the bound form. After short term HTO exposure in plants, the formation and uptake of OBT were evaluated.

• The Journal of the Korea Contents Association
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• v.8 no.8
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• pp.285-292
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• 2008

This study was initiated to evaluate the Phosphorus(P) leaching potential in the putting green soils and P uptake by the turfgrass in the golf course using the P fertilizers. The turfgrass, Floradwarf bermudagrass(Cynodon dactylon L. PERS,) was planted and grown in the mixture of sand and peat moss in this lysimeter study. Five representative P fertilizers, such as, ammonium polyphosphate (APP), monopotassium phosphate (MKP), MAP(monoammonium phosphate), 0-20-20(liquid), and concentrated superphosphate(CSP, solid) were used in this study. Based on the total P quantity of leachate collected during the whole 12 weeks, MKP and APP are the first group of P fertilizers contributing to the leaching of P, then MAP and 0-20-20 are the second group of P fertilizers causing the P leaching. Finally, CSP is the third group of P fertilizer resulting in the P leaching. However, most of P applied and collected in the lysimeter were leached during the first period of two and four weeks, compared to that of P leached during the second period of six, eight, ten, and twelve weeks. Applications of MAP, APP and CSP, MKP and 0-20-20 in order produced the largest amount of total dry matter. However, APP, MKP and MAP, CSP and 0-20-20 in order showed the largest amount of P uptake. Therefore, based on the data of P leaching, dry matter production, and plant P uptake, it appears that CSP, 0-20-20, and MAP are the environmentally sound fertilizers recommended in the turfgrass putting green soil of golf course.

• Journal of Life Science
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• v.31 no.1
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• pp.59-65
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• 2021

Prunus mume Sieb. et Zucc is distributed throughout Asia and has traditionally been used as medicine and food. P. mume is known to contain large amounts of various organic acids, minerals, and phenol components. To date, the trend of P. mume research has focused only on the effects of antioxidant, anticancer and antibacterial, with only a few studies have focused on angiogenesis. Angiogenesis is a common characteristic of metastatic cancer through which oxygen and nutrients are delivered to the cells and tissues. In the present study, angiogenesis-inhibiting activity was investigated by evaluating the total polyphenol and flavonoid contents of the P. mume butanol fraction (PBF) and their ability to inhibit VEGF-induced human umbilical vein endothelial cells (HUVECs) proliferation, migration, invasion, and capillary formation. The polyphenols (12.81 mg GAE/g) and flavonoids (28.4 mg QE/g) of the PBF exhibited high antioxidant activity. The results of this study showed that PBF did not inhibit the proliferation of HUVECs at concentrations of 25-200 ㎍/ml and did not exhibit toxicity to normal cells. However, PBF inhibited the VEGF-induced mobility, invasion, and capillary formation of HUVECs. These results show that PBF inhibits the angiogenesis of HUVECs induced by VEGF. Therefore, PBF could serve as a therapeutic agent for the inhibition of angiogenesis.

• Asian Journal of Turfgrass Science
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• v.23 no.1
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• pp.133-142
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• 2009

This study was initiated to evaluate the K leaching potential in the green soils and K uptake by the turfgrass in the golf course using the K fertilizers. The turfgrass, Floradwarf bermudagrass(Cynodon dactylon L. $P_{ERS}$.) was planted and grown in the mixture of sand and peat moss in this lysimeter study. Eight representative K fertilizers, such as, monopotassium phosphate (MKP), KCL, $K_2SO_4$, $KNO_3$, CKCl, $CK_2SO_4$, $CKNO_3$, and 0-20-20(liquid) were used in this study. Based on the total K quantity of leachate collected during the whole 12 weeks, 0-20-20 is the K fertilizers the most contributing to the leaching of K, then MKP, the second, KCL, the third, and finally $KNO_3$ are K fertilizers contributing to the K leaching. However, most amount of K applied and collected in the lysimeter were leached during the first period of two and four weeks, compared to that of K leached during the second period of six, eight, ten, and twelve weeks. Application of CKCL and $CK_2SO_4$ producted the largest amount of total dry matter, then MKP and KCL, $KNO_3$ and $CKNO_3$, 0-20-20 in second group. However, except $K_2SO_4$, most K fertilizer sources such as MKP, KCL, $KNO_3$, CKCL, $CK_2SO_4$, $CKNO_3$, 0-20-20 showed the largest amount of K uptake, except $K_2SO_4$. Therefore, based on the K leaching, dry matter production, and plant K uptake, it appears that the coated fertilizers, CKCL, $CKNO_3$, and $CK_2SO_4$ are the environmentally sound fertilizers recommended in the turfgrass green soil of golf course.

• Journal of Wetlands Research
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• v.20 no.4
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• pp.295-303
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• 2018

Inland wetlands in the Republic of Korea provide key breeding and wintering habitats, while coastal wetlands provide nutrient-rich habitats for stopover sites for East Asia/Australasia Flyway(EAAF) migrants. However, since the 1960's, Korea has reclaimed these coastal wetlands gradually for agriculture and urban expansion. The habitat loss has rippled across global populations of migrant shorebirds in EAAF. To protect a similar loss, the United States, specifically Missouri, developed the moist-soil management technique. Wetland impoundments are constructed from levees with water-flow control gates with specific soils, topography, available water sources, and target goals. The impoundments are subjected to a combination of carefully timed and regulated flooding and drawdown regimes with occasional soil disturbance. This serves a dual purpose of removing undesirable vegetation, while maximizing habitat and forage for wildlife. Flooding and drawdown schedules must be dynamic with constantly shifting climate conditions. Korea's latitude ($N33^{\circ}25^{\prime}{\sim}N38^{\circ}37^{\prime}$) is comparable to Missouri ($N36^{\circ}69^{\prime}{\sim}N40^{\circ}41^{\prime}$); as such, moist-soil management could prove to be an effective wetland restoration technique for Korea. In order to meet specific conservation goals (i.e. shorebird staging site restoration), it is necessary to test the proposed methodology on a site that can meet the required specifications for moist-soil management. Moist-soil management has the potential to not only create key habitat for endangered wildlife, but also provide valuable ecosystem services, including water filtration.

• Polymer(Korea)
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• v.32 no.2
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• pp.163-168
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• 2008

Biomedical scaffold for tissue regeneration was fabricated by one of rapid prototyping processes, bioplotting system, with a biodegradable and biocompatible poly($\varepsilon$-carprolactone)(PCL). Through dynamic mechanical test, it was observed that the PCL scaffold manufactured by the bioplotting process has the superior mechanical properties compared to the conventional scaffold fabricated by a salt-leaching process, and the plotted scaffold could be employed as a potential scaffold to regenerating hard and soft tissue. The plotted scaffold was consisted of porous structures. which were interconnected with each pore to help cells be easily adhered and proliferated in the wall of pore tunnels, and metabolic nutrients can be transported within the matrix. By using the plotting system, we could adjust the pore size, porosity, strand pitch, and, strand diameter of PCL scaffolds, which were important parameters to control mechanical properties of the scaffolds, and consequently we could determine that the mechanically controlled scaffolds could be used as a matching scaffold for any required mechanical properties of the target organ. The fabricated 3D PCL scaffold showed enough possibility as a 3D biomedical scaffold, which was cell-cultured with chondrocytes.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.12
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• pp.641-646
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• 2016

Soil organic matter (SOM) is an important soil component releasing nutrients to the plants and reducing risks of soil contamination to the human and ecosystem. Much attention has been recently paid to SOM investigation and management because SOM holds the most of carbon in the earth and sequestrate carbon as a sink tank. The first objective of the study was to investigate SOM of 495 soil samples taken at the Korea Soil Quality Monitoring Network. Soil samples were collected from 16 regions and 8 land use types. The second objective of the study was to find a relationship between the Tyurin method and loss-on-ignition (LOI) method for SOM. The means of SOM by Tyurin and LOI methods were 1.90 and 2.92 % (w/w), respectively. Land uses such as forest, religious area and park where organic matters continuously supply to normally showed higher SOMs than residential and school areas having sandy soils. A regression equation of the relationship between Tyurin and LOI methods was y(Tyurin) = 0.6257x(LOI) + 0.0602 (P-value < 0.001). The coefficient of determination was $R^2=0.749$, relatively linearly related. Although LOI may result in higher SOMs than the Tyurin method, LOI may be a preference for the SOM investigation if various kinds of land uses and many soil samples should be measured.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.70-70
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• 2003

조류의 배자는 포유류의 배자처럼 모체로부터 영양분을 공급받는 것이 아니라 알속에 저장되어 있는 영양물질로 발육한다. 배자의 발육은 대부분 체외에서 진행된다. 난자는 배란된 후 수정되어 난관팽대부에서 1세포기 수정란이 된다. 그 후 난관협부로 이동하여 최초로 분열이 일어나 배자의 발육이 진행되고, 산란시에는 세포수가 약6만여 개에 달한다. 따라서 수정란에 유전조작기법을 사용하기 위해서는 모체의 난관속에서 일어나는 배발생과 난각속에서 일어나는 개체발생을 위한 체외배양법과 대리난각 배양법이 확립되어 있어야 한다. 그와 같은 기술은 닭 수정란의 배 발생 관찰 및 분석과 유용한 물질을 생산하기 위한 형질전환 가금 연구에 중요한 기술로 사용되고 있다. 따라서 본 연구는 1세포기 닭 수정란의 체외배양과 대리난각 배양에 있어서 수정란의 조건과 대리난각의 조건이 배자의 생존율과 부화율에 미치는 영향을 조사하여 체외배양과 대리난각 배양에 의한 병아리 생산 효율을 제고하기 위한 기초자료를 얻고자 실시하였다. 주요 조사 항목은 수정란의 채란위치, 배자의 발생단계, 수정란의 무게, 대리난각용 계란의 보존 기간, 대리난각의 두께, 대리난각 두께의 감소율, 대리난각의 크기 등을 조사하여 배자의 생존율과 부화율에 미치는 영향에 대하여 조사하였다. 본 실험의 결과는 초기 발생이 빠른 배자가 생존율과 부화율이 높았으며, 본 실험에 사용한 대리난각용 계란의 보관기간이 짧을수록 배자의 생존율과 부화율이 높은 것으로 조사되었다(p<0.05). 그러나 대리난각용 계란의 크기와 대리난각의 두께 차이는 배자의 생존율과 부화율에 큰 영향이 없는 것으로 조사되었다.하였을 때 분할율은 68.0%였으며, 이중 12.0%가 상실배 또는 배반포로 발달하였다. 뿐만 아니라 10% FBS가 첨가된 TCM-199 배양액에 난관상피세포와 공배양을 실시하였을 경우는 72.0%가 분할하였으며, 이중 16.7%가 상실배 또는 배반포로 발달하였다. 이상의 결과로 볼 때 활성화 처리는 ionomycin과 6-DMAP 용액처리가 적합하며, 단위발생란의 체외배양은 보다 적합한 배양조건의 확립이 필요한 것으로 생각된다.icalcium lactate 공동배양은 체외배양에 별다른 영향을 미치지 못하는 것으로 나타났다.생산하는 것을 확인할 수 있었다.4시간에 등급별 회수율이 각각 GI(27.4%), GII(14.7%), GIII(43.2%), GIV(14.7%)로 나타났으며, 46~50시간에는 GI(12.0%), GII(12.0%), GIII(28.0%), GIV(48.0%)로 나타났다. 이상의 결과로 볼 때 미성숙 난자의 회수는 hCG 투여 후 29~34시간이 적합한 것으로 생각된다. 가금의 생산에 있어서 매우 효율적이고 주목할 만한 방법으로 사료된다. 것으로 나타났다.적외선.열풍 복합건조방법이 높게 나타나 이것은 곡물 표면에 원적외선 방사에의한 복사열이 전달되어 열장해를 받았기 때문으로 판단되며, 금후 더 연구하여 적정 열풍온도 및 방사체 크기를 구명해야 할 것이다.으로 보여진다 따라서 옻나무 유래 F는 포유동물의 생식기능에 중요하게 작용하는 것으로 사료된다.된다.정량 분석한 결과이다. 시편의 조성은 33.6 at% U, 66.4 at% O의 결과를 얻었다. 산화물 핵연료의 표면 관찰 및 정량 분석 시험시 시편 표면을 전도