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Background and objective This study was conducted to determine the effect of NaCl on the growth, antioxidants (superoxide dismutase, proline), maximum quantum yield, and chlorophyll contents of Pseudolysimachion pusanensis. Methods Five levels of NaCl concentrations (0, 50, 100, 200, 400 mM) were used for treatment. Results The growth according to NaCl concentrations was highest at 50 and 100 mM, but root growth declined before the top from 200 mM or higher. The increase in NaCl concentrations also led to the increase in SOD and proline content compared to the control plot, whereas it decreased chlorophyll content. There was no difference in the maximum quantum yield at 0, 50, 100, and 200 mM, but it decreased at 400 mM. Conclusion The results proved that P. pusanensis showed an increase in SOD and proline content at 50 and 100 mM of NaCl treatment compared to the control plot, indicating that it receives salt stress, but the growth was excellent at 50 and 100 mM. In addition, there was no difference in top growth up to 200 mM compared to the control plot, and there was no significant difference in the maximum quantum yield, which proved that P. pusanensis has strong tolerance to salt stress.

In order to examine the variation characteristics of chemical compositions in accordance with the different meteorological conditions, PM10 and PM2.5 were collected at Gosan site of Jeju Island in 2014, and then their ionic and elemental species were analyzed. The concentrations of nss-SO4 and NH4 were respectively 4.3 and 3.3 times higher in fine particle mode (PM2.5) compared to coarse particle mode (PM10-2.5), however NO3concentration was 1.6 times higher in coarse mode compared to fine particle mode. During Asian dust days, the concentrations of nssCa and NO3increased highly as 7.7 and 4.5 times in coarse particle mode, and 3.0 and 4.9 times higher in fine particles, respectively. Especially, the concentrations of the crustal species (Al, Fe, Ca, K, Mn, Ba, Sr, etc.) indicated a noticeable increase during the Asian dust days. For the haze days, the concentrations of secondary pollutants increased 2.2~2.7 and 2.9~6.0 times in coarse and fine particles, respectively, and they were 0.8~1.1 and 1.8~2.4 times, respectively, during the mist days. The aerosols were acidified largely by sulfuric and nitric acids, and neutralized mainly by ammonia in fine particle mode during the haze days, but neutralized by calcium carbonate in coarse particle mode during the Asian dust days. The clustered back trajectory analysis showed that the concentrations of nss-SO4, NO3-, and NH4 + were relatively high when the inflow pathway of air mass was from the southern part of China.