To analyze the water characteristics in the dry and wet seasons, the data for temperature, salinity, nutrients and chl-a were used, which were observed in the south coastal area of Korea during April to October 2000. At Yeosu in the south coast of Korea, the higher values of 35.0 psu in salinity were shown in March and April, the lower values of 23.0 psu in salinity were shown in August and September. The annual range of salinity was 12.0 psu. The total amount of precipitation in the wet season (July to October) was occupied 68% (about 846 mm) during 2000. The precipitation of the dry season (November to June) was occupied 32% (about 394 mm) in the year. In the coastal area, the salinity variation is distinct in the period of July to October. Based on this result, we divided the season into two parts: the dry season during April to June and the wet season during July to October. Factor analysis was shown that temperature has strong negative relation and nutrients show positive relations in the dry season by the factor 1, which explains the total variance of 50.6% at the surface water. In the wet season, salinity has negative relation and nutrients show positive relation by the factor 2, which explains the total variance of 33.5%. The bottom layer also showed similar to those of surface water in the results of factor analysis. These mean that nutrients become rich due to the freshwater inflow in the wet season. The low saline water is shown not only in the south coast but also in the overall region in the South Sea of Korea. It is suggested that the South Sea of Korea may call a ROFI (Region of Freshwater Influence) system in summer.
Male and female strobilus production was assessed annually over a five-year period for a clonal seed orchard of sugi (Cryptomeria japonica D. Don) in Korea. Clonal fertility and fertility variation, expressed by both sibling coefficient and coefficient of variation in strobilus production among 40 orchard clones, were reported. Fertility varied among clones and among years, producing five-year averages per ramet of 464.3 and 971.1 for female and male strobili, respectively. The correlation between female and male strobilus production was positive in each of the five years studied and statistically significant with the exception of one poor flowering year. The clonal status number (Ns), a measure of genetic diversity, was calculated based on the observed clonal fertility variation, varying from 27.6 (N = 40) in the poorest flowering year (2002) to 35.8 in the best year (2005). On average (pooled), the relative status number was 95% of the census number (N). Variation of female fertility was higher than that of male fertility for the five consecutive years, and the status numbers of female and male parents reflected this variation. The pooled Ns estimation from all five years was higher than any single year, implying that genetic diversity would increase when seeds collected from different years are pooled. Sexual asymmetry calculations showed that clonal contributions would be balanced between genders
Based on the monthly weather report of Korea Meteorological Administration (KMA) and daily sea surface temperature (SST) data from National Fisheries Research and Development Institute (NFRDI) (1995-2004), mean heat fluxes were estimated at the port of Yeosu. Net heat flux was transported from the air to the sea surface during February to September, and it amounts to 205 Wm-2 in daily average value in May. During October to January, the transfer of net heat flux was conversed from the sea surface to the air with -70 Wm-2 in minimum of daily average value in December. Short wave radiation was ranged from 167 Wm-2 in December to 300 Wm-2 in April. Long wave radiation (Sensible heat) was ranged from 27 (-14) Wm-2 in July to 90 (79) Wm-2 in December. Latent heat showed 42 Wm-2 with its minimum in July and 104 Wm-2 with its maximum in October in daily average value.
국립수산진흥원의 한국 연안 어장환경 오염조사 결과 보고서를 사용하여, 인천 연안역의 수온 및 염분의 계절변화의 특성을 살펴 보았다. 수온의 연변화는 인천항과 소래에 이르는 조간대 해역이 만의 바깥쪽 해역보다도 수온의 연평균이 높고, 진폭도 크며, 위상도 빨랐다. 염분의 연변화는 인천항과 소래에 이르는 조간대 해역이만의 바깥쪽 해역보다도 연평균은 낮고, 진폭은 크며, 위상은 느리게 나타났다. 이러한 특성은 T-S도를 이용하여 나타낸 수괴의 계절 변화에서도 뚜렷하게 볼 수 있었다. 즉, 인천 연안역의 수괴는 수온과 염분의 연교차가 큰 인천과 소래에 이르는 조간대 해역과 염분 변동에 영향을 주는 강수나 증발, 담수 유입의 계절적 변화에 비교적 영향을 적게 받는 만의 바깥쪽 해역으로 구분할 수 있었다. 또한 얕은 수심과 강한 조류로 인하여 수층이 연중 거의 혼합된 분포를 보이고 있었다.
The object of this study was to determine the difference of the time course changes of transpiration, diffusion resistance and photosynthetic rate of rice at several different growth stages subjected to soil moisture stress (SMS) and recovery by irrigation. A japonica rice cultivar 'Dongjinbyeo', was grown under flooded condition in a plastic container filled with silty loam soil. At 5 main growth stages, the container was treated by SMS until initial wilting point (IWP) and then reirrigated. The duration of SMS until IWP were the longest, 13 days for tillering stage, and the shortest, 7 days for panicle initiation and meiosis stage. The transpiration rate rapidly decreased during SMS and the transpiration rate at IWP of the stressed plant showed 10∼20% compared with control, and the transpiration rate of stressed plant at most growth stages also recovered rapidly after irrigation and then reached 100% of control within a week. The shoot photosynthetic rate in all growth stages rapidly decreased by SMS, and the rates at IWP of stressed plants were de-creased nearly to 0%, beside the treatment at tillering stage. The recovery degree of photosynthetic rate by irrigation ranged from 20 to 90%, showed higher at early growth stages of SMS treatment than that of later stages. At all growth stages the leaf diffusion resistance of stressed plants was over 3 times that of the control resulting from a rapid increase at 3 to 5 days after draining for SMS, and showed quick recovery by irrigation within 3 days after drainage. The above physiological parameters changed in close relation with the decrease of the soil matric potential after SMS. These results indicate that at all main growth stages of rice plants the transpiration and photosynthesis reduction by stomatal closure reponded sensitively to the first stage of SMS closely related with decrease of soil water potential, while those recovery pattern and recovered degree by irrigation are little different by growth stage of rice.
Based on the monthly weather report of Korea Meteorological Administration (KMA) and daily sea surface temperature (SST) in Incheon harbor of National Fisheries Research and Development Institute, heat budget in Incheon coastal area was estimated.
The temperature differences between the sea surface and near bottom were nearly within 1℃. This indicate the mixing from the sea surface and the bottom. The net heat flux through the sea surface and the advection through the inner and outer bay was affected uniformly to the water body in Incheon coastal area.
The net heat flux was about 110W/㎡ in maximum value on May, about -80W/㎡ in minimum on January. The net heat flux through the sea surface from the solar radiation was about 2.35 × 105W during the year. This heat flux flew out the bay through the advection by the same flux.
Based on the Results of Marine Meteorological and Oceanographical Observations (1966∼1987), the phenomenon of chimney is found as a candidate for the formation of the Japan Sea Proper Water (JSPW). The chimney phenomenon occurs twelve times during 1966∼1987. The water types in the chimney denoting the deep convection are similar to those of the JSPW, 0∼1 ℃ in potential temperature, 34.0∼34.1‰ % in salinity and 68∼80 cl/t in potential thermosteric anomaly from the sea surface to the deep layer. The static stabilities in the chimney stations are unstable or neutral. This indicates that the winter time convection occurs. The JSPW sunken from the surface layer of chimney in winter spreads out under the Tsushima Warm Current area, following the isosteric surface of about. 76 cl/t in potential therniosteric anomaly. The formation of the deep water of the JSPW is mainly affected by the cooling of the sea surface than the evaporation of winds because the temperature and the salinity on the isoteric surface of about 76 cl/t in potential thermosteric anomaly are cold and low. The phenomenon of chimney occurred in here and there of the area in the north of 40˚ 30` N, west of 138°E. This suggests that the deep water of the JSPW is formed not in a limited area but. probably in the overall region of the northern open ocean.
Based on the Results of Marine Meteorological and Oceanographical Observations (1966∼1987), oceanographic conditions of the Japan Sea in winter was studied in relation to the Japan Sea Proper Water (JSPW). The mean and dispersion of the deep water above 1000m depth are O.26±0.2℃ in temperature and 5.1±0.25 ㎖/ℓ in oxygen. The mean and dispersion of the bottom water below 1000m depth are 0.07±0.04℃ in temperature and 5.1±0.15㎖/ℓ in oxygen. The distributions of the temperature and dissolved oxygen in the deep water above 1000m depth are ranged wider than those of the bottom water below 1000m depth in T-S and T-O_2 diagrams. The bottom water are showed more homogeneous and smaller variations than the deep water in the characteristics of water mass. The deep water above 1000m depth is active in contact with the atmosphere. The JSPW similar to the above characteristics is showed in the open ocean of the north of 40°30` N, west of 138°E. Therefore, the deep water is formed probably by the open-ocean convection.
Based on the Results of Marine Meteorological and Oceanographical Observations during 1966∼1987 and the Ten-day Marine Report during 1970∼1989 by Japan Meteorological Agency, the possible area where the Japan Sea Proper Water (JSPW) can be formed is investigated by analyzing the distribution of water types in the Japan Sea. The Japan Sea can be divided into three subareas of Northern Cold Water(NCW), Polar Front(PF) and Tsushima Warm Current (TWC) by the Polar Front identified by a 6℃ isothermal line at the sea surface in winter. Mean position of the Polar Front is approximately parallel to the latitude 39∼40°N. The standard deviation of the Polar Front from the mean position of about 130㎞ width is the smallest in the region between 136°E and 138°E where the Polar Front is very stable, because the branches of the Tsushima Current are converging in this region. However, standard deviations are about 180∼250㎞ near the Korean peninsula and the Tsugaru Strait due to greater variability of warm currents. In the NCW area north of 40°30`N and west of 138°E, the water types of the sea surface to the 100m depth are similar to those of the JSPW. This fact indicates that the surface layer of the NCW area is the possible region of the JSPW formation in winter.