• Title/Summary/Keyword: Meteorological and Oceanographic Factors

Search Result 13, Processing Time 0.02 seconds

A Comparative Study on Outbreak Scale of Cochlodinium polykrikoides Blooms (Cochlodinium polykrikoides 적조발생규모에 대한 비교연구)

  • Kang, Yang-Soon;Park, Young-Tae;Lim, Weol-Ae;Cho, Eun-Seob;Lee, Chang-Kyu;Kang, Young-Shil
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.14 no.4
    • /
    • pp.229-239
    • /
    • 2009
  • To understand major factors that affected on distinct Cochlodinium bloom scale in Korean coasts in 2007 and 2008, oceanographic and meteorological characteristics during Cochlodinium bloom period were compared. The main reason for large scale blooms in 2007, covering both southern coast and eastern coast with about 10 million US dollars fish kills, was attributed to sufficient nutrient supply by heavy rainfall, upwelling in the coast arising from irregular wind shift, weak thermocline and low grazing pressure by zooplanktons during Cochlodimum bloom development period. On the contrary, small scale blooms in 2008 covering only inshore areas of southern coast without fish kills was attributed to the low nutrient level in coastal areas by long persistent drought and strong influence of oligotrophic offshore water onto inshore and high grazing pressure by extra ordinarily abundant zooplanktons during Cochlodinium development period. Conclusively, it was estimated that nutrient level, strength of offshore water and feeding pressure might play a significant role in the difference of bloom scale between the two years.

Oceanographic Conditions in Relation to Laver Production in Kwangyang Bay, Korea (광양만의 김 생산과 양식장환경과의 관계에 대하여)

  • HONG Jae-Sang;SONG Choon Bok;KIM Nam-Gil;KIM Jong Man;HUH Hyung Tack
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.20 no.3
    • /
    • pp.237-247
    • /
    • 1987
  • The present study deals with the physico-chemical and meteorological conditions in Porphyra-cultivation ground to determine the relationship between laver production and its environmental factors in Kwangyang Bay from January to April in 1986. As a result, major environmental factors which are thought to have a great influence upon the poor harvest during the cultivation period are as follows; 1) the excessive rainfall in the beginning of cultivation period 2) the accumulation of suspended matters on the thallus of laver 3) the decrease of current velocity and the stagnation of the water in the cultivation ground.

  • PDF

Study on the Distribution Patterns of Anchovy Eggs and Larvae and Environmental Characteristics in the Eastern Part of Jeju Strait, Korea (제주해협 동부해역에 있어서 멸치 난·자치어의 분포패턴과 환경 특성)

  • Lee, Seung-Jong;Go, You-Bong
    • Korean Journal of Ichthyology
    • /
    • v.18 no.1
    • /
    • pp.36-44
    • /
    • 2006
  • The distribution patterns of anchovy eggs and larvae and environmental characteristics such as oceanographic conditions and meteorological factors in the eastern part of Jeju Strait, Korea from June to October 2003 were investigated. During the sampling periods, the anchovy spawned on the coastal area mainly and approximately 85% of total egg abundance occurred in only two months, from July to August, suggesting that the main spawning season of anchovies is considered in summer from July and August in the study area. Relatively high proportions of the anchovy larvae larger than 20 mm TL observed in the eastern part area. These facts suggest that anchovy larvae gradually moved out to the eastern part of study area. Most wind speeds were markedly reduced to below 10 m/s with the exception of a few days and the precipitation was concentrated (37%) from July to August when the anchovy eggs and larvae occurred abundantly. Results of correlation analysis showed that the anchovy egg abundance correlated with the increasing chlorophyll a and copepod biomass. It is considered that the plankton biomass in the sea area would have significant effects on the anchovy spawning. In addition, salinity variations also had significant effects on the abundance of anchovy larvae, with increasing water temperature.