秋季红沿河核电站海域水龄分布及其对水母丰度分布的影响

The distribution of water age and its effect on jellyfish abundance in Hongyanhe Nuclear Power Plant in autumn

本研究调查了秋季红沿河核电站海域镭、氡同位素的活度水平及分布情况,结合镭同位素表观年龄模型计算该海域的水体年龄,进而得出研究区域的水体运移方向,初步探讨了水母丰度分布与水体运移的相关关系。得到结论如下:(1)红沿河核电站海域表层水体中224Ra、226Ra及222Rn的活度水平分别为2.9~62.4 dpm/(100 L),11.9~57.4 dpm/(100 L)及0.1~1.3 dpm/L,镭同位素活度呈现出近岸高、远岸低的分布趋势,氡同位素的分布则更大程度上受水温控制;(2)通过224Ra/226Ra表观年龄模型计算得出红沿河海域表层水体年龄范围介于0~16 d,平均年龄(10.9±3.6) d,水体主体流向为北偏东方向,流速为7.2 cm/s;(3)水母丰度分布与水体流向呈现出较为一致的对应关系,在主体流向方向上,水体年龄较大的海域水母丰度最高。

In this study, the activity range and distribution patterns of radium and radon isotopes in the coast sea of the Hongyanhe Nuclear Power Plant were investigated in autumn, 2017. The water ages were calculated by "Apparent Radium Age Model", which distribution was then used to assess the major direction of water transport in the study area. We also discussed the relationship between jellyfish abundance distribution and water transport direction. The results indicate that:(1) the activity ranges of 224 Ra, 226 Ra and 222 Rn were 2.9-62.4 dpm/(100 L), 11.9-57.4 dpm/(100 L), and 0.1-1.3 dpm/L in the study area in autumn, respectively.(2) Based on the "Apparent Radium Age Model", the so-calculated water ages were ranged from 0 to 16 d, with an average of(10.9±3.6) d. The major water transport direction was towards northeast with the velocity of 7.2 cm/s.(3) There was clear correlation between the distribution of jellyfish abundance and the major water transport direction. The higher jellyfish abundance was found in main water transport direction with older water ages.