Long-term Variation in the Catch of Major Small Pelagic Fishes Related to Winter Warming in the South Sea, Korea

摘要

The relationships among long-term climatic change in the southern part of the Korean peninsula,oceanic conditions of the South Sea, Korea, and winter catches of major small pelagic fisheswere analyzed using 33 years of time-series data from 1971-2003. In the early 1990s, winterclimatic conditions in the southern part of the Korean peninsula shifted to a warmer regime withhigher air temperature, weaker wind speed, and lower relative humidity. Also, winter sea surfacetemperature (SST) became consistently higher in the South Sea. The annual catch of major smallpelagic fishes in the South Sea increased dramatically in the mid 1990s, whereas the catch oftotal fishes decreased in the late 1980s. In particular, the winter catch started to increasemarkedly in the late 1980s, and has remained over 120,000 M/T since the late 1990s. Correlationanalysis of the winter catch of major small pelagic fishes and environmental factors showed thatcatch was correlated with air temperature (r=0.468, P<0.01), wind speed (r=-0.732, P<0.01),relative humidity (r=-0.731, P<0.01), and SST (r=0.672, P<0.01). Multiple regression analysisbetween the winter catch of major small pelagic fishes (Y) and environmental factors (X) resultedin the equation: 7=- 0.017-0.217 X_3- 0.486 X_4 + 0.325 X_5 (R~2 = 0.754, P < 0.000).