Biodiversity of benthic megafauna on the deep-sea plains with polymetallic nodules in the Northwestern Pacific Ocean
编号:1242 访问权限:仅限参会人 更新:2024-10-14 13:04:00 浏览:191次 口头报告

报告开始:2025年01月17日 09:45(Asia/Shanghai)

报告时间:15min

所在会场:[S59] Session 59-Impacts of Climate and Biogeochemical Extremes on Marine Organisms and Ecosystems [S59-1] Impacts of Climate and Biogeochemical Extremes on Marine Organisms and Ecosystems

暂无文件

摘要
Northwestern Pacific encompasses various typical deep-sea habitats, including seamounts, plains, and trenches. Among them, the deep-sea plains may be rich in polymetallic nodules, offering abundant patchy hard substrates that provide diverse habitats and refuges for benthic and infaunal organisms. The deep-sea nodule plains are characterized by high habitat heterogeneity, supporting diverse organisms. Growing interest in deep-sea mining has emerged, yet the potential environmental impacts remain largely unknown, making environmental concerns a critical barrier. Understanding the habitat characteristics of deep-sea nodule plains and the distribution patterns of megafaunal biodiversity is fundamental for effective deep-sea environmental management and is essential for fulfilling commitments under the Agreement on the Conservation of Marine Biological Diversity in Areas Beyond National Jurisdiction.
This study conducted underwater optical surveys using a towed optical vehicle, collecting a large number of high-definition seabed images from the polymetallic nodule contract area in the Northwestern Pacific. The biodiversity and distribution patterns of megafauna in the nodule habitat were analyzed. A total of 37,558 valid seabed photographs were obtained, covering approximately 350 km of seabed transects at a depth of around 5,500 m, and 7,062 megafauna individuals were counted. Each organism was identified to the lowest possible taxonomic level according to the collected biological specimens and existing literatures. In total, 206 morphological species of megafauna were identified, belonging to nine phyla. Therein, holothurians and sponges were the dominant groups in the deep-sea nodule plains, accounting for 35.3% and 23.3%, respectively. It suggested that the polymetallic nodule contract area supported relatively low organism abundance but high biodiversity. An analysis of two near-seafloor transects adjacent to a deep-sea seamount revealed that as the distance from the seamount increased, one transect demonstrated a gradual decline in the Shannon diversity index, species richness, and evenness, while the other transect exhibited an opposing trend. Beta diversity analysis indicated that the beta diversity index remained high overall, with species turnover as the dominant biological process. Cluster analysis showed significant differences in species composition within the deep-sea nodule plains, with the proportions of holothurian Elpidiidae increasing closer to the seamount. Redundancy analysis revealed that the distribution of megafauna in the nodule plains is influenced by multiple interacting environmental factors, with depth, nodule coverage, bathymetric position index, slope, and near-bottom current velocity being key environmental drivers. This study provides fundamental biological data for deep-sea environmental management.
关键词
Deep-sea habitat,Megafauna,Polymetallic nodules,Deep-sea mining,Northwestern Pacific Ocean
报告人
Leyi Fang
graduate Second Institute of Oceanography; Ministry of Natural Resources

稿件作者
Leyi Fang Second Institute of Oceanography; Ministry of Natural Resources
Dongsheng Zhang Second Institute of Oceanography
Chengcheng Shen Second Institute of Oceanography; Ministry of Natural Resources
Chunsheng Wang Second Institute of Oceanography; Ministry of Natural Resources
发表评论
验证码 看不清楚,更换一张
全部评论
重要日期
  • 会议日期

    01月13日

    2025

    01月17日

    2025

  • 09月27日 2024

    初稿截稿日期

  • 01月17日 2025

    注册截止日期

主办单位
State Key Laboratory of Marine Environmental Science, Xiamen University
承办单位
State Key Laboratory of Marine Environmental Science, Xiamen University
Department of Earth Sciences, National Natural Science Foundation of China
联系方式
移动端
在手机上打开
小程序
打开微信小程序
客服
扫码或点此咨询