| 摘要: |
| 为了解喀斯特高原湖泊万峰湖鱼类资源分布状况，于2021年5月采用美国BioSonics DT-X分裂波束回声探测仪(Split-beam digital echo sounder system)对万峰湖天生桥电站以上约66 km的库区进行声学走航调查。声学结果显示，探测总航程约为73 km，探测平均水深为27.92±12.40 m，探测水深范围为4.40—99.40 m，河段水深由上游至下游呈逐步变深的趋势；共获鱼类信号6401个，平均目标强度-53.71 dB，范围-69.86—-29.14 dB，以-58—-55 dB这个区间分布最多(931个)；垂直方向上，以水深在36—42m水层鱼类目标强度最大(-50.38?7.20) dB，12—18m水层内最小(-60.68?11.38) dB。整个江段鱼类平均密度为0.74 ind/1000m3，以万峰湖镇附近鱼类密度最高，达到了88.84 ind/1000m3；在垂直方向上，以水深0—6 m内这一水层密度最高，达到了5.23 ind/1000m3，水深大于60 m水层鱼类密度最低(0.01 ind/1000m3)，各水层鱼类密度随水深增加逐渐降低。万峰湖鱼类主要分布在靠近村庄、城镇附近水域的中上层水体中。相关性分析显示，鱼类密度分布与水温、浮游植物生物量呈显著正相关（P<0.05），与总溶解度、盐度、离子氨浓度呈显著负相关关系(P<0.05)。研究系统探明了万峰湖鱼类资源分布特征及其影响因素，可为万峰湖鱼类资源养护提供参考。 |
| 关键词: 万峰湖 鱼类资源 空间分布 水声学 环境因子 |
| DOI： |
| 投稿时间：2024-11-21修订日期：2025-01-19 |
| 基金项目:贵州省科技计划项目(黔科合支撑[2020]4Y027)；珠江流域渔业资源与栖息地调查专项(ZJZX-02)；农业部淡水生物多样性保护重点实验室开放课题(LFBC0901) |
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| Hydroacoustic estimates of fish distribution characteristics and influencing factors in Wanfeng Lake, a karst plateau lake |
|
heshiwen1, lijuyi2, liuzhuo1, lankaiyong1, wangyizhou1, dongxianghong1, shaojian1
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| (1.guizhou university;2.zhongguoshuichankexueyanjiuyuanchangjiangshuichanyanjiushuo) |
| Abstract: |
| To understand the distribution of fish resources in the karst plateau lake Wanfeng Lake, a hydroacoustic survey was conducted from May to November 2021 using the American BioSonics DT-X split-beam echo sounder system (Split-beam digital echo sounder system) for a navigational survey covering approximately 66 kilometers of the reservoir area upstream of the Tianxingqiao Hydropower Station. The acoustic results showed that the total navigational distance for detection was approximately 73 km, with an average detected water depth of 27.92 ± 12.40 m, and the water depth range was from 4.40 m to 99.40 m. The water depth increased gradually from upstream to downstream. A total of 6,401 fish signals were detected, with an average target strength of -53.71 dB, ranging from -69.86 dB to -29.14 dB. The majority of the signals (931) were distributed within the range of -58 dB to -55 dB; Vertically, the greatest fish target strength was observed in the water layer with a depth of 36-42 m, with an average target strength of -50.38 ± 7.20 dB. The smallest target strength was found in the water layer with a depth of 12-18 m, with an average target strength of -60.68 ± 11.38 dB. The average fish density for the entire river section is 0.74 ind/1000m3, with the highest density found near Wanfeng Lake Town, reaching 88.84 ind/1000m3; In the vertical direction, the highest fish density was observed in the water layer from 0 to 6 meters deep, reaching 5.23 ind/1000m3. The lowest fish density was found in the water layer deeper than 60 meters (0.01 ind/1000m3). Fish density decreased gradually with increasing water depth across different layers. The main distribution of fish in Wanfeng Lake is in the upper and middle water layers near villages and towns. Correlation analysis showed, The distribution of fish density is significantly positively correlated with water temperature and phytoplankton biomass (P<0.05), and significantly negatively correlated with total dissolved solids, salinity, and ammonium ion concentration (P<0.05). This study has elucidated the distribution characteristics of fish resources in Wanfeng Lake and their influencing factors, providing a reference for the conservation of fish resources in Wanfeng Lake. |
| Key words: Wanfeng Lake Fish Resources Spatial Distribution Hydroacoustics Environmental Factors |
