The feathery branched green alga Bryopsis plumosa (Hudson) C. Agardh bloomed at Songji Beach, Haenam, Korea, in November 2022. A terrible stench was present on the beach, and the bottom was covered in a thick green mat of green algae. The alga was identified as B. plumosa, which is an opportunistic species currently distributed worldwide. Dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP) were analyzed in the bloomed area and compared with those of other vicinities. The DIN and DIP concentrations were 1.067 and 0.461 mg L-1, respectively, which were 6 to 19 times higher than the average concentrations on southwest coasts, including Haenam. The B. plumosa bloom at Songji Beach in November 2022 appears to have depended on DIN and DIP concentrations in seawater. In this study, we report on the mass occurrence of B. plumosa, which appeared for the first time in Korea. This occurrence was found to be closely related to the concentration of nutrients in seawater. Therefore, it is necessary to manage the concentration of nutrients on land flowing into coastal waters to control green algal blooms such as Bryopsis.

In this study, the concentrations of various hydrocarbon (HC) were measured from the ambient air at Mallipo beach after the Hebei Spirit oil spill accident on Dec. 2007. To determine HC levels in those samples, the analysis was made by SPME method aided by the GC/MS system. To produce quantitative HC data, all the calibrations were conducted in reference to toluene. The HC released from oil-covered soils were also analyzed by headspace method; according to this analysis, the concentrations of paraffinic (9), aromatic (8) and miscellaneous components (5 compounds) were found above a few tens of ppb. In ambient samples, 10 compounds were measured which consisted of 8 paraffinics and 2 aromatics. And they have the maximum and minimum concentration that were 34.3 ppb (n-undecane) and 2.84 ppb (toluene). However, the concentration levels of the 2 aromatic compounds (toluene and xylene) measured during this study period were not distinguished from those commonly observed from ambient air. Based on our analysis, we were able to confirm that the types and the concentration levels of hydrocarbons in ambient samples were in accord with those derivable from a large oil spill accident and the resulting weathering processes.

Concentrations of hydrogen sulfide in ambient air have been measured from January 2014 to June 2016 in a coastal area near the Ulsan National Industrial Complex. The measurement sites were 1 km, 2.6 km, 5.6 km, and 20 km away from a kraft pulp mill, which is located at the most southern edge of the complex. Concentrations above 0.4 ppb were monitored every 5 min and the highest concentration of the day was determined. From a total of 775 measurement days, hydrogen sulfide concentrations > 20 ppb were recorded on 36 and 38 days at the measurement site closest to the mill and the residential area 2.6 km away from the mill, respectively. At the site farthest from the mill, the concentrations were always 20 ppb lower than the malodor regulation for the residential area but sometimes higher than the odor recognition threshold for hydrogen sulfide. Although several emission sources of hydrogen sulfide have been published in the Pollutant Release and Transfer Register of Korea, the kraft pulp mill is considered to be the biggest contributor of atmospheric hydrogen sulfide in the southern coastal area of Ulsan.

Abnormal change in Gyeongpo beach shoreline in June of 2012 was illustrated using DGPS (Differential Global Positioning System, resolution < 0.6m) observation and drift experiment. Abrupt change in the shoreline was occurred in the latter part of June, 2012, this change was compared with that in June from 2009 to 2011. In the northern part of the beach, sand accumulated and it made beach extension and movement of the shoreline towards sea compared with that in June from 2009 to 2011. While on the other, in the southern part, the beach was eroded and it formed a steep slope around the southernmost of the beach. The shoreline in the southern part of the beach was shifted more towards land than that in the past. Change in the position of shoreline was higher in the northernmost and southernmost of the beach compared with those in the other parts. Drift in the southern part of the beach moved faster along the beach than that in the northern part of it.