润扬大桥水下噪声特征及其对水生生物的潜在影响初探

The characteristics of underwater noise around the Runyang Bridge and its potential impact on aquatic organisms

于2019年4月在长江镇江段润扬大桥正常通车状态时进行桥梁周边水域水下噪声特征测量,计算不同点位水下噪声平均声压级(Sound pressure level,SPL),并进行带宽20 Hz-20 kHz的噪声频谱分析。结果表明:润扬大桥正常通车状态时周边水下噪声以低频为主(<200 Hz),主频率峰值范围为20-2000 Hz。桥梁下方水下噪声平均声压级为117.96±3.25 dB,大桥交通噪声被同频声场覆盖,主频率不明显。当船舶通过时噪声增益较为明显,能量集中于低频(1 kHz以下)部分,声压级集中在120-130 dB,将背景噪声(2000 m处)平均声压级提高了约7-17 dB。基于该水域可能存在的水生生物及其听阈特性评价水下噪声对其产生的潜在影响,为长江水生生物生态保护提供理论基础。

The underwater noise characteristics around the Runyang Bridge in Zhenjiang section of the Yangtze River were measured in April 2019.The average sound pressure level(SPL)of underwater noise at different sites were calculated,and the noise spectrum of bandwidth of 20 HZ-20 kHz was analyzed.The results show that the underwater noise around the Runyang Bridge is mainly low frequency(below 200 Hz),and the peak frequency is 20-2000 Hz.The average sound pressure level of underwater noise under the bridge is 117.96±3.25 dB.The resonance noise of the bridge is covered by the same frequency sound field,and the main frequency is not obvious.However,in the reverberation sound field,ship noise is more obvious.The energy is concentrated in the low frequency(below 1 kHz),and the sound pressure level is concentrated at 120 dB-130 dB,which increases the average sound pressure level of background noise(at 2000 m)by about 7-17 dB.Based on the possible aquatic organisms in the water area and their hearing threshold characteristics,the potential impact of underwater noise on them is evaluated,which provides a theoretical basis for the ecological protection of aquatic organisms in the Yangtze River.