Assessment of phytoplankton invasion risks in the ballast water of international ships in different growth conditions

Abstract

The possibility of successful invasion by phytoplankton assemblages in the ballast water of twelve international commercial ships was investigated. Various scenarios of port water dilution rates with a time delay for the exponential growth of the plankton were considered. Most of the phytoplankton in the ballast water samples originated in countries such as Japan and China, and diatoms dominated (>90% abundance) these phytoplankton communities. To assess their survival after discharge in seawater under various conditions, the phytoplankton were reintroduced into ballast water, pier-side water, and nutrient-enriched f/2 medium and incubated at various water temperatures and salinities for 2 weeks. The growth of the invading phytoplankton was influenced by the time delay for regrowth when introduced in the new seawater conditions. The results also suggest that once introduced by ballast water, the growth of a phytoplankton community may depend more on the nutrient levels and the water temperature and less on the salinity. Although we did not consider parameters such as competition with native species and predation, both high nutrient concentrations and water temperatures may significantly shorten the period before exponential growth occurs, which increases the invasion potential.

Ballast Water: A Polyphasic Approach in the Evaluation of Potential Phytoplanktonic Bioinvasion

“…Diatoms showed a more pronounced development than others did, with high acclimation and potential for establishment in local ambient. This kind of result corroborates for Hyun et al (2017) and Klein et al (2010), who affirmed the high survival capacity of that group in confined environments. This result may be related to the presence of frustules (Cupp, 1943) which give cell protection, resistance and robustness to the systems of cultivation and manipulation.…”

Potential Applications of a Novel Ballast Water Pretreatment Device: Grinding Device

“…The annual amount of ballast water that is used for the safe operation of vessels reaches approximately 3.5 gigatons and is discharged into the world's oceans [1][2][3]. Various marine organisms, such as bacteria, microorganisms, and invertebrates are present in the ballast water.…”

Long-term Changes of Disinfection Byproducts in Treatment of Simulated Ballast Water

“…For example, Choi et al (2005) found greater variation in the mid-ocean upon exchange (2-28°C) than in samples collected upon arrival (11-25°C) in the San Francisco Estuary. The water temperature in the ballast water of ships entering ports in Korea was found to sometimes be higher than the water temperature of the port by approximately 1-2°C, although this difference reflects the seasonal changes in water temperature of the marine environment (Jang et al 2016;Hyun et al 2017). In freshwater, an increase in temperature results in faster consumption of total residual oxidants (TROs) or chlorine, leading to a positive correlation with several DBPs, especially THMs and HAAs (Roccaro et al 2008;Zhang et al 2013b).…”