Clithon retropictus has been protected by the Ministry of Environment as an endangered species since 1998 and has been listed on the state red list of endangered species category II. It is viewed as a representative for all endangered species in the northeastern coastal waters of Korea. Most of the habitats of C. retropictus have been found to be in an unstable state because of development projects such as road construction, small stream development, irrigation for securing agricultural water, and flood prevention. These habitats are damaged by small stream maintenance projects and development, and the risk of damage is increasing and active efforts are needed in order to protect them. Although the Ministry of Environment is striving to preserve this endangered species, the habitat of C. retropictus is still facing external threats because it spreads to only a small area at high densities. Therefore, in order to protect the habitat of C. retropictus, a level II endangered species, it is urgent to make an effort to minimize habitat damage and to take measures for its protection.

The objective of this study was to identify the main floral scents and their relative contents in the floral organ of Nelumbo nucifera. N. nucifera flower, a traditional Chinese medicinal herb, is rich in volatile compounds. In this study, the volatile components of N. nucifera flowers were investigated by headspace solid-phase microextraction gas chromatography-mass spectrometry for each organ of the flower: petals, sepals, pistils, and stamens. In total, we identified 39 compounds, among which aliphatics were major constituents, representing more than 94% of petals and sepals volatiles, followed by sesquiterpenes representing more than 69% of pistils and stamens volatiles. Pentadecane, 1-pentadecene, 8-hexadecyne, 8-heptadecene, and β-caryophyllene characterize the scent of the N. nucifera flower. We identified 24 volatiles in petals and sepals, 25 volatiles in pistils, and 18 volatiles in stamens. Among the monoterpenes, 3-Isopropylidene-4-methylcyclohexene, isoterpinolene, p-Menth-2-en-7-ol, and methyl 2,6,6- trimethylcyclohex-1-enecarboxylate were analyzed and identified for the first time from the N. nucifera flower. This study demonstrates that N. nucifera flowers differ greatly in volatile composition depending on the floral organ of the plant.

This study used SCS-CN method to estimate the real recharge of the study area which is one of the most reasonable techniques to estimate groundwater recharge when there is no available runoff data in a watershed. From the results of the real recharge analysis for the study area using SCS-CN method, it was analyzed that the year 1994 when the drought was severe showed the lowest recharge of 106.3mm with recharge rate of 12.4%, and the highest recharge of 285.6mm with recharge rate of 21.8% occurred in 1990. Yearly average recharge of 213.2mm was obtained, and the average recharge rate was 16.9%/year. KOG-FLOW model which has powerful post process functions consists of setting environments for input parameters in Korean language, and help function is added to each input data. Detailed information for each parameter is displayed when the icon is placed on the input parameters, and geologic boundaries or initial head data for each layer can be set easily on work sheet. The relative errors (R. E.) for each model’s observed values and calculated values are 0.156~0.432 in case of KOG-FLOW, and 0.451~1.175 in case of WINFLOW, therefore it is known that KOG-FLOW model developed in this study produced results compared to observed head values.