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Studies on the bloom timing of moon jellyfish (Aurelia aurita) in the nearshore waters of
the Hongyanhe River – an estuary of the Liaodong Bay
Chunjiang Guan, Guize Liu, Qing Yang and Jinqing Ye
National Marine Environmental Monitoring Center, Dalian, PR China.
E-mail:
[email protected]
In recent years, the aggregation or outbreak of marine organisms can block the cold source
water system of power plant, and bring high risk to its normal operation, including the bloom
of moon jellyfish (Aurelia aurita) which is becoming a serious ecological disaster in the
nearshore waters of the Liaodong Bay. The bloom of this jellyfish can jam the cooling system
of power plant resulting in the high risk for the closing of nuclear power plant. In order to
ensure the normal operation of the nuclear power plant, we used an anchor drift net to
monitor the relative density, bell diameter, wet weight of moon jellyfish every 3 days from
June to August in 2015 and 2016 in the eastern part of the Liaodong Bay. The results showed
that the bloom timing of moon jellyfish ranged from early July to mid-August when is a high
risk period for the cold source water of nuclear power plant, also showed plaque distribution
of moon jellyfish. The maximum relative density was up to 11,952ind./(net.h), bell diameter
for 24cm, wet weight for 590g on 23rd July 2015, and on 14th August 2016 the maximum
relative density was up to 16,667ind./(net.h), bell diameter for 18cm, wet weight for 360g. It
is urge to compile a catalogue of the risk marine organisms and make the risk calendar of
moon jellyfish bloom in order to guide the early disposal strategy and ensure the safe
operation of its cold source water system of nuclear power plant.