• 한국물환경학회지
• /
• 제25권6호
• /
• pp.910-915
• /
• 2009

The ecohydrologic characteristics according to planting in riparian zone for the riparian restoration are analyzed in this research. The ecohydrologic components due to land use change in riparian zone from existing land cover to planted area such as pasture and wildrye are simulated in the test basin with the integrated SWAT-MODFLOW model. After analysis of change of the hydrologic properties such as surface flow, lateral flow, transpiration and soil water in riparian zone, it is revealed that soil water is one of the key factors and planting of wildrye can increase soil water in riparian zone. The simulation performance of the SWAT-MODFLOW model is validated in this study and it is expected that this model can be used to evaluate various riparian restoration scenarios.

• The Plant Pathology Journal
• /
• 제40권2호
• /
• pp.192-204
• /
• 2024

In this study, the efficacy of the essential oil of Mentha longifolia, Achillea arabica and Artemisia absinthium plants were evaluated against important soil-borne fungal pathogens as Verticillium dahliae, Rhizoctonia solani, and Fusarium oxysporum. Essential oils were obtained from plants by hydrodistillation method and the chemical components of essential oils were determined by analyzing by gas chromatography-mass spectrometry. The main components found as piperitone oxide (13.61%), piperitenone oxide (15.55%), pulegone (12.47%), 1-menthone (5.75%), and camphor (5.75%) in M. longifolia, á-selinene 13.38%, camphor 13.34%, L-4-terpineneol 8.40%, (-)-á-Elemene 7.01%, 1,8-cineole 4.71%, and (-)-spathulenol 3.84% in A. arabica, and á-thujone (34.64%), 1,8-cineole (19.54%), pulegone (7.86%), camphene (5.31%), sabinene (4.86%), and germacrene-d (3.67%) in A. absinthium. The antifungal activities of the oils were investigated 0.05, 0.1, 0.25, 0.5, 1.00, and 2.00 μl/ml concentrations with the contact effect method. M. longifolia oil (1.00 and 2.00 μl/ml) has displayed remarkable antifungal effect and provided 100% inhibition on mycelial growth of V. dahliae, R. solani and F. oxysporum. The results obtained from this study may contribute to the development of new alternative and safe methods against soil-borne fungal pathogens.

• 한국환경과학회지
• /
• 제10권3호
• /
• pp.209-216
• /
• 2001

Dustfall particles were collected by the modified American dust jar (wide inlet bottle type) at 6 sampling sites in Pusan area from March, 1999 to February, 2000. Thirteen chemical species (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Si, and Zn) were analyzed by AAS and ICP. The purposes of this study were to estimate qualitatively various bulk deposition flux of dustfall and insoluble components by applying regional and seasonal distribution. Dustfall amount of regional variations were found in order of coastal zone, industrial zone, commercial zone, agricultural zone and residential zone, and seasonal total dustfall had higher concentrations during spring for 6.741 ton/${km}^2$/season, lower concentrations during summer for 1.989 ton/${km}^2$/season, and annual total concentration was 17.742 ton/${km}^2$/year. The regional distributions of enrichment factor show well-defined anthropogenic metals (Cd, Cu, Pb, and Zn) at industrial and agricultural zone, and contribution rate of soil particles were found in order of summer, fall, winter and spring. Factor loading effects of chemical composition of dustfall were found in order of road traffic emission source and combustion processed source, industrial activity source, soil source and marine source.

• 한국대기환경학회지
• /
• 제6권2호
• /
• pp.183-191
• /
• 1990

To check the possible transportation of gaseous air pollutants with the particles of yellow sand in the movement of air masses during the Yellow Sand Phenomenon, the concentrations of such air pollutants as TSP, $SO_2, CO, NO_x, O_3 and N-CH_4$, and wind wpeed were measured during the Yellow Sand Phenomenon (April 8 $\sim 10, 1990) and they were compared with those during the normal times in Korea. Meanwhile dust color of the samples during the Yellow Sand Phenomenon was the color of sand, that during the normal times was dark-brown. The concentrations of dusts; water soluble components, and metallic components of soil-originated elements during the Yellow Sand Phenomenon were higher than those during the normal times. While the metallic components in the dusts during the Yellow Sand Phenomenon were from soil-originated elements, those during the normal times were of both soiloriginated and sea-originated elements. The change of hourly concentrations of air pollutants showed bi-modal distribution during the two periods. Generally, the concentration levels of air pollutants during the Yellow Sand Period were higher than those during the normal times. Although similarity was observed in the primary sources, differences were observed in the dynamics of the secondary sources due to chemical reactions of the air pollutants during the two periods.

• Earthquakes and Structures
• /
• 제14권5호
• /
• pp.411-424
• /
• 2018

This study explores the inelastic behavior of systems with flexible base. The use of a single degree of freedom system (ESDOF) with equivalent ductility to represent the response of flexible base systems is discussed. Two different equations to compute equivalent ductility are proposed, one which includes the contribution of rigid body components, and other based on the overstrength of the structure. In order to asses the accuracy of ESDOF approach with the proposed equations, the behavior of a 10-story regular building with reinforced concrete (RC) moment resisting frames is studied. Local and global ductility capacity and demands are used to study the modifications introduced by base flexibility. Three soil types are considered with shear wave velocities of 70, 100 and 250 m/s. Soil-foundation stiffness is included with a set of springs on the base (impedance functions). Capacity curves of the building are computed with pushover analysis. In addition, non linear time history analysis are used to asses the ductility demands. Results show that ductility capacity of the soil-structure system including rigid body components is reduced. Base flexibility does not modify neither yield and maximum base shear. Equivalent ductility estimated with the proposed equations is fits better the results of the numerical model than the one considering elastoplastic behavior. Modification of beams ductility demand due to base flexibility are not constant within the structure. Some elements experience reduced ductility demands while other elements experience increments when flexible base is considered. Soil structure interaction produces changes in the relation between yield strength reduction factor and structure ductility demand. These changes are dependent on the spectral shape and the period of the system with fixed and flexible base.

• 한국자원식물학회지
• /
• 제28권1호
• /
• pp.93-100
• /
• 2015

유채 종자에서 기름을 착유한 후 부산물인 유채박을 토양에 처리하여 토양 내 선충을 친환경적으로 방제하기 위하여 실험한 결과를 보면, 유채박을 혼합한 토양이 OM, $Av.P_2O_5$, Ca, Mg, CEC 등의 수치가 증가하였으며, 유기물함량은 무처리 토양보다 3배가량 높게 나타났다. 또한 유채박의 glucosinolate 함량은 제주재래종 유채박이 $199.97{\mu}mol/g$로 선망 유채박의 함량보다 $76.62{\mu}mol/g$ 더 많았으며, 특히 progoitrin, gluconapin, glucobrassicanapin, 및 sinigrin 등의 함량이 높게 나타나기 때문에 유채박의 선충밀도 감소에 효과가 있으며 '선망' 유채박보다 제주재래종 유채박이 선충밀도를 더 줄여주었지만 유의적인 차이는 아니었다.

• Earthquakes and Structures
• /
• 제26권5호
• /
• pp.401-416
• /
• 2024

Long-span structures, such as bridges, can experience different seismic excitations at the supports due to spatially variability of ground motion. Regarding current bridge designing codes, it is just EC 2008 that suggested some regulations to consider it and in the other codes almost ignored while based on some previous studies it is found that the effect of mentioned issue could not be neglected. The current study aimed to perform a comprehensive study about the effect of spatially varying ground motions on the dynamic response of a reinforced concrete bridge under asynchronous input motions considering soil-structure interactions. The correlated ground motions were generated by an introduced method that contains all spatially varying components, and imposed on the supports of the finite element model under different load scenarios. Then the obtained results from uniform and non-uniform excitations were compared to each other. In addition, the effect of soil-structure interactions involved and the corresponding results compared to the previous results. Also, to better understand the seismic response of the bridge, the responses caused by pseudo-static components decompose from the total response. Finally, an incremental dynamic analysis was performed to survey the non-linear behavior of the bridge under assumed load scenarios. The outcomes revealed that the local site condition plays an important role and strongly amplifies the responses. Furthermore, it was found that a combination of wave-passage and strong incoherency severely affected the responses of the structure. Moreover, it has been found that the pseudo-static component's contribution increase with increasing incoherent parameters. In addition, regarding the soil condition was considered for the studied bridge, it was found that a combination of spatially varying ground motions and soil-structure interactions effects could make a very destructive scenarios like, pounding and unseating.

• 한국약용작물학회지
• /
• 제17권6호
• /
• pp.439-444
• /
• 2009

This study was to set the guidelines of soil chemical components in order to assure the safety and quality of the panax ginseng from physiological disorder. The disorder symptoms appeared on the leaf with yellow spot, atrophy, yellow-brown spot, also showed red skin and rough skin of the root. Occurrence type of physiological disorder in cultivated field divided into two types : type I 'such as, yellow spot' consist of single disorder symptom; type II 'such as, yellow spot and yellow-brown spot' consist of two or more different disorder symptoms. The individual contribution of soil properties to the occurrence type was as follows ; The yellow spot was affected by Na > $NO_3$-N > salinity (EC) in soil. The same results was observed in red skin. Atrophy was affected by $NO_3$-N > salinity (EC) > Ca > Mg. Rough skin was affected by $P_2O_5$>pH>Organic material > K. It showed positive associated to $P_2O_5$, pH and K, but negative associated to organic matter. Simultaneous occurrence of two different disorder, including cases which yellow spot and yellow-brown spot, those were affected by $NO_3$-N > salinity (EC) > Na > Mg. In the case of atrophy plus yellow-brown spot, those also were affected by in the order : $NO_3$-N > salinity (EC) > Ca > Mg > Na. Red-rough skin was affected in the order : salinity (EC) > $NO_3$-N > K > Na. Soil chemical components appear to be related to occurrence of physiological disorder, particularly in salinity (EC) and $NO_3$-N. The salinity (EC) and $NO_3$-N were negative related to plant growth. In addition, exchangeable cation capacity play critical roles in attributing to complex occurrence of physiological disorder.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제45권1호
• /
• pp.35-41
• /
• 2022

Mulberry is a hardy, perennial, deep-rooted plant capable of thriving under diverse agroclimatic conditions. The selection of suitable land and appropriate variety can help the sustainable mulberry field. However, no conclusive and comprehensive investigation has been conducted on the mulberry soil properties and nutritional composition of mulberry cultivars from Korea local areas in previous studies. In our study, soil properties and mulberry leaf components of Korea local mulberry farms were briefly investigated. In result, the soil organic matter (OM) content was significantly high in Buan (6.81%) and Jangseong (6.14%). In contrast, available phosphate (P₂O₅) was different in each local area. To investigate relationship between soil property and nutritive component of mulberry leaf, Cheongil leaf samples from 8 local areas were analyzed. Among the macrominerals (K⁺, Ca²⁺, Na⁺, and Mg²⁺), the concentration of K varied from (1884±9.36) mg/100 g to (2685±11.5) mg/100 g. The potassium (K⁺) of Cheongil leaf in Sangju was the highest at 2685 mg/100 g. Besides macrominerals, flavonoids, total dietary fiber contents and moisture of Cheongil leaf samples were studied in the 8 local areas. In terms of these contents, the variation was largely depending on the local areas. This study provides a possible industrial use of mulberry, and holds promise to enhance the overall profitability of sericulture.

• 임산에너지
• /
• 제24권1호
• /
• pp.13-27
• /
• 2005

새로운 산림용 복합비료를 개발하기 위하여 소나무, 낙엽송, 자작나무, 상수리나무 묘목을 대상으로 성분비가 다른 비료 및 종류가 다른 고형복합비료를 처리하고 묘목의 부위별 양분 농도를 측정하였다. 질소, 인, 칼륨의 비를 각기 달리한 시비수준별 처리실험에서 질소와 인 시비 후 묘목내 이들 양분의 농도가 증가하였다. 또한 소나무와 상수리나무에서 칼륨 시비량 증가에 따라 묘목 내 양분 농도가 증가하는 효과를 보였으나, 나머지 두 수종에서는 처리별 차이가 나타나지 않았다. 산림용 고형복합비료와 UF 고형복합비료를 처리한 비료 종류별 처리실험에서는 시비량이 증가할수록 묘목 내 질소와 인의 농도가 증가하는 현상이 나타났다. 소나무에서의 칼륨 농도와 낙엽송에서의 나트륨과 칼슘 농도도 유사한 현상을 보였으며, 나머지 수종에서는 처리별 차이를 나타내지 않았다. 비료의 종류를 달리하여 처리한 결과 묘목 내 양분 농도 변화 효과는 없는 것으로 나타났다.