玻璃钢水槽内大黄鱼养殖环境噪声测量与分析

利用水下声音测量系统,分别记录了开放式圆形玻璃钢水槽内养殖环境噪声和大黄鱼(Larimichthys crocea)摄食过程声音,并进行声压级(sound pressure levels,SPL)计算和频谱特征分析。结果表明:(1)养殖环境噪声SPL约为110.27 d B(d B re:1μPa),包括主频率峰值为100 Hz的养殖工作设备与水槽内壁的低频共振噪声、1 250 Hz的表层水体气泡噪声、1 600~2 500 Hz的曝气石、增氧机、空气压缩机工作噪声;(2)增氧机和曝气关闭时,大黄鱼摄食过程声音SPL约为92.65 d B,高于背景噪声SPL,主要为游泳声音70~500Hz、吞食产生的水体表面搅动与气泡破裂的声音1 000~2 000 Hz、咀嚼颗粒饵料声音2 000~4 500 Hz;(3)增氧机和曝气开启时,背景噪声SPL略高于摄食声音约17.62 d B,且摄食声音无法区别于背景噪声,但并未影响鱼类摄食行为。

Measurement and analysis of the aquaculture noise for Larimichthys crocea in the fiberglass fish tank

In recent years,researchers have focused on the welfare and the ethical treatment in aquaculture and thus,considered the effects of the aquaculture facilities noises on the health of the breading fishes.In general conditions,the noise would not lead to the death of fish directly,but the fish exposed to a high intensity noise for a short time would cause temporary threshold shift,stress level increase,blood circulation system and nerve tissue damage.Moreover,it would also cause fish behavior changing,such as escaping from the feeding place or spawning place for the noises.More seriously,the fish feeding conversion,growth efficiency rates,survival and reproduction rate would reduce in a long time noises exposure to the noises and ultimately affect the breeding production.The aquaculture ambient noise and the feeding sound of large yellow croaker (Larimichthys crocea) in the open fiberglass fish tanks were monitored by a passive acoustic monitoring system.The results showed that:(1) The SPL of the aquaculture ambient noise was about 110.27 dB (dB re:1 μPa).They were mainly the aquaculture facilities working sound in the low frequency bandwidth (100 Hz),surface bubbling sound (1 250 Hz),as well as the air-stones,air compressor and aeration facility working sound in the high frequency bandwidth (1 600 Hz to 2 500 Hz);(2) When the aeration and air-stone were turned off,the SPL of the Larimichthys crocea feeding sound was about 92.65 dB,including swimming sound (70 Hz to 500 Hz),water surface agitation and bubble burst sound produced by swallowing (1 000 Hz to 2 000 Hz) and chewing pellet feeds sound (2 000 Hz to 4 500 Hz);(3) When the aeration and air-stone were turned on,the SPL of the aquaculture ambient noise was 17.62 dB,higher than the feeding sounds,but could not be distinguished,and the fish feeding behavior was not affected.The experiment was designed to provide references for developing a healthy soundscape for the indoor aquaculture by equiping shock absorption and noise reduction aquaculture facilities,and also for the study on the future development of ethical treatment and automatic feeding control for the dense aquaculture tanks.