海洋低频噪声对褐菖鲉声讯交流神经机制的影响

Ocean noise pollution is another major environmental problem caused by human activities. The potential effect of ocean noise pollution on aquatic animals is well-recognized. Recently, the negative impact on fish began to attract attention. A few studies have shown that low frequency noise pollution has been found to alter hearing sensitivity and auditory responses of fishes. However, the underlying mechanism linking noise pollution and these diverse responses is unknown. In the present study, we firstly found that the rockfish produce different sounds in different behavior conditions, and noise exposed significant decrease their sound-evoked feeding behavior. We then present the proposal that the low frequency noise pollution might affect the acoustic communication of rockfish. We plan to apply multiple electrophysiological approach to dissect the neural mechanism, from the sound production to auditory threshold and auditory processing mechanism. Taken together, our findings will have a comprehensive understanding of how noise pollution to affect the sensory and behavioral neural system of fish, which is essential for predicting the impact of noise pollution on marine ecosystem and marine fisheries economy.

海洋噪声污染是人类活动引起的又一重大环境问题，一些研究表明，许多海洋生物面临着海洋噪声污染的巨大威胁，近年来海洋低频噪声污染对鱼类的影响也逐渐引起关注。有报道海洋低频噪声可能引起鱼类听觉敏感性和行为的改变，但其影响机制未知。我们以发声鱼类褐菖鲉为材料，发现褐菖鲉在不同行为环境下的发声特征存在差异，且噪声暴露降低其对活饵的摄食效率，推测噪声可能对其声讯交流神经机制造成影响。因此，利用多种神经电生理技术，研究噪声暴露下褐菖鲉的声讯交流神经机制的影响，从发声特征到听觉阈值及听觉信息神经处理模式的改变。从神经机制层面上，系统的研究海洋低频噪声对鱼类感觉和行为神经系统可能的影响机制，为预测海洋噪声污染对海洋生态系统和渔业经济的影响提供科学依据。

海洋来自于海洋工程的低频噪声污染日益严重。噪声污染对鱼类的影响也备受关注。本项目以褐菖鮋为研究对象，探讨了海上风电场的低频噪声对其声讯交流的影响。通过海上实测，风电机在水下的产生的噪声主要有25Hz，63Hz，125Hz。考虑到声音在水中传播截止频率的存在，只考虑了125 Hz以上的低频噪声的影响评价。噪声对鱼类的影响主要有听觉感知，遮蔽，伤害等。通过双通道被动声呐技术监测和计算了水下噪声的衰减模型，在实验室采用多通道电生理技术，通过记录实验鱼脑电波确定其听觉频率选择性和听觉阈值，结果表明，褐菖鮋的听觉敏感范围是100-300Hz。根据声音衰减模型和褐菖鮋的听觉阈值，其感知区域是32-6310m，遮蔽区域是10-501m。风电场的水下噪声对褐菖鮋的伤害较小。 但24小时噪声暴露实验也表明，低频噪声降低了褐菖鮋的发声频率，结果其发声机制，说明低频噪声可通过影响发声肌的收缩频率来调节其发声频率，但风电场噪声暴露并没有明显改变褐菖鮋的以脑电波基础的听觉阈值。