Flux measurement of jellyfish near Hongyanhe Nuclear Power Station area in summer by using acoustic methods
FU Yuanyuan1, TANG Yong1*, WANG Shan1, MENG Wei2, WANG Shuai1, LIU Xiaolin2
1.College of Marine Science and Environment, Dalian Ocean University, Dalian 116023, China; 2.Suzhou Nuclear Power Research Institute, Suzhou 215004, China
Abstract: The influx of jellyfish flooding into the water intake of the nuclear power plants threatens the safety of the water taken of the nuclear powder cold source. In order to grasp the density and basic movement of jellyfish in the sea near the Hongyanhe Nuclear Power Station, a survey ship equipped with scientific fishfinder (120, 200 kHz) and Doppler velocity profiler (ADCP) was used in the waters near the Hongyanhe, and the survey ship was carried out for 25 h along the vertical isobath in the summer of 2017, July, August, and September. Acoustic resource survey and tidal current observation of 10 n mile vertical section was conducted reciprocating navigation, and samples of jellyfish were collected by multi-anchor nets in the next day. The frequency difference processing technology was used to separate the superimposed acoustic scattering signals of jellyfish Aureliaaurita, Nemopilemanomurai and other plankton. The echo integration method was used to estimate the density of Aureliaaurita and Nemopilemanomurai, and the flux of the jellyfish through the survey section was calculated based on the tidal data. The results showed that the maximum flow velocity was shown to be 0.80 m/s in July, 0.70 m/s in August and 0.65 m/s in September. The speed of the ocean current was gradually increased and decreased with the cycle of rising and falling tides. There was higher average density of Aureliaaurita than that of Nemopilemanomurai, 9.79 and 2.30 ind./m2 in July; 11.05 and 1.51 ind./m2 in August; 0.82 and 0.32 ind./m2 in September. Aureliaaurita had average fluxes of 5.85 ind./(s·m2) in July, 3.53 ind./(s·m2), in August and 0.40 ind./(s·m2) in September at high tides. The average flux was -2.84 ind./(s·m2) in July, -6.07 ind./(s·m2) in August, and -0.36 ind./(s·m2) in September at low tide. The average flux of Nemopilemanomurai was 1.45 ind./(s·m2) in July, 0.44 ind./(s·m2) in August and 0.17 ind./(s·m2) in September; the average flux at low tide was -0.86 ind./(s·m2) in July, -0.76 ind./(s·m2) in August, and -0.13 ind./(s·m2) in September at high tides, indicating that that the flux of jellyfish was correlated with changes in the speed of fluctuations and tidal currents, which can well reflect the movement trend of jellyfish. Jellyfish as an important indicator for the monitoring and early warning of cold source biology in nuclear power plants is featured by random distribution in the sea outside the water intake, which is suitable for acoustic buoy monitoring.
付媛媛, 汤勇, 王珊, 孟威, 王帅, 刘笑麟. 基于声学技术的红沿河核电站附近海域夏季水母通量测量[J]. 大连海洋大学学报, 2021, 36(2): 325-333.
FU Yuanyuan, TANG Yong, WANG Shan, MENG Wei, WANG Shuai, LIU Xiaolin. Flux measurement of jellyfish near Hongyanhe Nuclear Power Station area in summer by using acoustic methods. Journal of Dalian Ocean University, 2021, 36(2): 325-333.
2021, Vol. 36 
