• Korean Journal of Breeding Science
• /
• v.43 no.6
• /
• pp.554-558
• /
• 2011

A single cross hybrid, 'Eolrukchal 1', is a bicolor waxy corn (Zea mays L.) developed by the maize breeding team at the National Institute of Crop Science (NICS), RDA in 2007. This hybrid, which has a high eating quality, was produced by crossing two inbred lines, KBW23 and KW33. KBW23 was a seed parent and KW33 was a the pollen parent of 'Eolrukchal 1'. Ear length and diameter of 'Eolrukchal 1' is 18.4 cm and 4.5 cm, respectively. The ratio of kernel set length/ear length is 89%, similar with that of a check hybrid, 'Chalok 1'. It is resistant to Exserohilum turcicum (Northern corn leaf blight) and its lodging resistance is higher than that of 'Chalok 1'. The yield of 'Eolrukchal 1' in fresh ear weight was 9.80 ton/ha and 14% higher than that of 'Chalok 1' in regional yield trials (RYT) from 2005 to 2007. A seed production of this hybrid has been well due to good match during crossing between the seed and the pollen parents. It is adaptable to the whole country except Jeju-do.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.25 no.3
• /
• pp.100-117
• /
• 2022

This study examines the spatio-temporal characteristics of the macrobenthic community in the coastal areas of South Korea for the past six years(2015-2020). The relationship between the number of individuals of macrobenthic species and the benthic environments were investigated using data collected at a total of 154 stations located in the West (70), the South (61), and the East Seas (23), except for the Jeju Sea. We examined the benthic environmental characteristics such as water depth, sediment, grain size, ignition loss, and total organic carbon. A total of 1,614 macrobenthic species were found in the coastal area, with a mean density of 0.62 ind./m² by station. The mean density was relatively high in the spring and summer seasons (May to August) with more than 450 species. The most dominant species belong to Polychaetes and the top five of them accounted for more than 20% of the total number of populations. The top five species were Heteromastus filiformis, Scoletoma longifolia, Sigambra tentaculata, Sternaspis scutata, and Notomastus latericeus. Cluster analysis was performed on the top five dominant species. The stations were clustered into three groups with similar locations on the West, South, and East Sea. Cluster 1 and 3 represent Heteromastus filiformis (44% each), but cluster 2 represents Scoletoma longifolia (66%). Each cluster has different benthic environmental characteristics, especially in the sediment's sand (31.0%, 51.9%) and clay (15.9%, 9.7%) contents.

• Journal of Korean Society for Atmospheric Environment
• /
• v.31 no.4
• /
• pp.330-344
• /
• 2015

Semi-continuous measurements of $PM_{2.5}$ mass, organic and elemental carbon were made for the period of January to October 2014, at six national air monitoring stations in Korea. OC and EC concentrations showed a clear seasonal variation with the highest in winter (January) and the lowest in summer (August). In winter, the high carbonaceous concentrations were likely influenced by increased fuel combustion from residential heating. OC and EC concentrations varied by monitoring stations with 5.9 and $1.7{\mu}g/m^3$ in Joongbu area, 4.2 and $1.2{\mu}g/m^3$ in Honam area, 4.0 and $1.3{\mu}g/m^3$ in Yeongnam area, 3.7 and $1.6{\mu}g/m^3$ in Seoul Metropolitan area, 3.0 and $0.8{\mu}g/m^3$ in Jeju Island, 2.9 and $0.7{\mu}g/m^3$ in Baengnyeong Island respectively. The concentrations of OC and EC comprised 9.6~ 15.5% and 2.4~ 4.7% of $PM_{2.5}$. Urban Joongbu area located adjacent to the intersection of several main roads showed the highest carbon concentration among six national air monitoring station. On the other hand, background Baengnyeong Island showed the lowest carbon concentration and the highest OC/EC ratio (4.5). During the haze episode, OC and EC were enhanced with increase in $PM_{2.5}$ about 1.3~ 3 and 1.3~ 4.0 times respectively. The concentrations of OC, EC in the Asian dust case are about 1~ 2.4 times greater than in the nondust case. The origins of air mass pathways arriving at Seoul, using the backward trajectory analysis, can be mostly classified into 6 groups (Sector I Northern Korea including the sea of Okhotsk, Sector II Northern China including Mongolia, Sector III Southern China, Sector IV South Pacific area, Sector V Japan, Sector VI Southern Korea area). When an air mass originating from northern China and Mongolia, the OC concentrations were the most elevated, with a higher OC/EC ratio (2.4~ 3.3), and accounting for 17% of $PM_{2.5}$ mass on average.