Re-growth ability and species composition of phytoplankton in international commercial ship’s ballast water

Abstract

The aim of this study is to assess the importance of ballast water discharge as a vector for the introduction of exotic species into Korean coastal and port water. Also, we examined to understand the impacts of environmental factors on the survival success of introduced species by ship’s ballast water in laboratory experiments. The duration time of ballast water in each ship was ranged from 1 to 365 days. The numbers of species and phytoplankton standing crops in uploaded ballast water were related to the duration time of ballast water the phytoplankton population densities in ship’s ballast water of short duration time was significant. Of these, the most diverse taxonomic groups were diatoms. In the laboratory study, the in vivo fluorescence of phytoplankton viability in Spring Lyra gradually increased with increasing nitrate and phosphate. Phytoplankton in new (9 days), medium (31 days) and old (365 days) ballast water successfully survived under the nutrient typical of shipside water and F/2 medium at 15˚C and 20 ˚C, whereas phytoplankton in ballast water treatment did not survive even in optimal temperature. Colonization process was dominated by diatoms, Skeletonema coastatum for Spring Lyra, Thalassiosira pseudonana and Thalassiosira for Han Yang, Thalassiosira pacifica and Odentella aurita for Modern Express, and Chaetoceros pseudocurvisetus and Pseudo-nitzschia seriata for Asian Legend. The successful estsurvival success of introduced species by ship’s ballast water in laboratory experiments. The duration time of ballast water in each ship was ranged from 1 to 365 days. The numbers of species and phytoplankton standing crops in uploaded ballast water were related to the duration time of ballast water the phytoplankton population densities in ship’s ballast water of short duration time was significant. Of these, the most diverse taxonomic groups were diatoms. In the laboratory study, the in vivo fluorescence of phytoplankton viability in Spring Lyra gradually increased with increasing nitrate and phosphate. Phytoplankton in new (9 days), medium (31 days) and old (365 days) ballast water successfully survived under the nutrient typical of shipside water and F/2 medium at 15˚C and 20 ˚C, whereas phytoplankton in ballast water treatment did not survive even in optimal temperature. Colonization process was dominated by diatoms, Skeletonema coastatum for Spring Lyra, Thalassiosira pseudonana and Thalassiosira for Han Yang, Thalassiosira pacifica and Odentella aurita for Modern Express, and Chaetoceros pseudocurvisetus and Pseudo-nitzschia seriata for Asian Legend. The successful est