한국 주요항만 연속 모니터링을 기반으로 확인된 잠재적 위해종의 항만별 분포와 수용능력

Abstract

Vulnerability of port environments to ship’s ballast water urged us to conduct baseline surveys at the busiest ports in Korea (Incheon, Gwangyang and Ulsan) to inform decisions about controlling the introduction of unwanted species. We surveyed for potentially harmful zooplankton (>200μm) and related environmental factors which are critical to the development of ballast water management methods in Korea. The red-tide heterotrophic Noctiluca scintillans, recognized as a blooming species causing hypoxia, frequently occurred at the ports from February 2007 to November 2009. Each port has distinctive coastal structure and is located in different bioregions of the Large Marine Ecosystems (LME) region. This species appeared consistently at all ports during the study period, indicating that it is eurythermal and euryhaline (1.97-28.00°C, 21.09-34.54 psu). Abundances of N. scintillans over 10,000 inds per m-3 were observed within the range of harbor limits at the three ports in spring and Gwangyang port in winter, coinciding with high concentrations of chlorophyll-a (~6.58 μg L-1). Maximum abundances of the species generally occurred at the outer stations of Incheon port, at the inner stations of Ulsan port and at all stations of Gwangyang port. Results indicated that Gwangyang port in spring is the most suitable environment for the introduction and reproduction of N. scintillans transferred outside the bioregion. Conversely, uptake of ballast water at the same time and place is likely to provide an opportunity to transfer and introduce this species to the other coastal ecosystems.