『Abstract
　The ionic composition of total suspended particulate (TSP) and fine (PM2.5) fractions was investigated from an 1,100 site in the middle of Mt. Halla in Jeju Island, Korea from March to November 2006. The sum concentrations of cation and anion species in TSP fraction were 205±170 and 183±164 neq m^-3, respectively, while those for PM2.5 as 118±129 and 88.5±89.3 neq m^-3, respectively. In TSP, the concentration of the major ions changed in the order of SO4^2-＞NH4⁺＞Ca²⁺＞Na⁺＞NO3^-＞Mg²⁺＞K⁺＞Cl^-, while its PM2.5 counterpart as NH4⁺＞SO4^2-＞Ca²⁺＞NO3^-＞Na⁺＞Mg²⁺＞K⁺＞Cl^-. Inspection of the temporal variabilities of ionic components indicated that most ions peaked in spring or fall months. The back trajectory analysis showed that the atmospheric composition of the major ionic species was affected fairly sensitively by long-range transport from China under the favorable meteorological conditions. In contrast, the lowest ionic concentration levels were seen most abundantly, when air masses passed from South Sea. Hence, the analysis of ionic concentration data suggests that their distributions are controlled by the combined effects of various source processes including the most prominent. Chinese origin and the meteorological condition favorable for such transport.

Keywords: Long-range transport; Ionic composition; Aerosol; Jeju』

1. Introduction
2. Materials and methods
　2.1. Sampling
　2.2. Analysis of aerosol samples
3. Results and discussion
　3.1. The overall picture of the ionic compositions between different particle fractions
　3.2. Evaluation of ion-to-ion ratios in relation to source processes
　3.3. The concentrations of ionic species measured by cascade impactor
　3.4. Temporal variabilities of ionic species
　3.5. Factors affecting the environmental behavior of ionic species
　3.6. Comparison with previous studies
4. Conclusions
Acknowledgements
References