| 摘要: |
| 陆海连续体是连接陆地生态系统和开阔海洋的过渡带，其连通性对生物迁移产生重大影响，但对陆海连续体连通性的描述和量化目前仍在探索之中。本研究利用环境DNA (eDNA)宏条形码技术，通过使用针对脊椎动物的通用引物对鱼类线粒体12S rRNA基因的部分V5高变区进行扩增，获得鱼类多样性数据，并以此为基础开发了一种快捷方法来评估陆海连续体的连通性。该方法通过计算相邻站点间的Beta多样性指数来综合估算生物连通性综合指数(comprehensive index of biological connectivity, CIBC)，该值范围0～1，值越大，连通性越好。2023年10月利用eDNA技术成功从长江口上海水域检测出鱼类21目，35科，86属，117种，其中支流的鱼类数量多于干流。Alpha 多样性分析显示，支流的鱼类群落丰富度高于干流，但多样性略低于干流。鲤科的CIBC值显示，干流、支流连通性普遍较好。鲴科的CIBC值显示，干流上下游连通性较好。鱊科的CIBC值显示，干流上游连通性较好。虾虎鱼科的CIBC值显示，干流中上游连通性较好。整个鱼类群落的CIBC值显示，干流连通性较好，仅下游接近长江口处连通性较差，支流的连通性变化较大，干流的整体连通性优于支流。本研究方法可为研究陆海连续体连通性提供新的思路，并有助于长江口生态廊道的生态修复与综合管理。 |
| 关键词: 陆海连续体|连通性|生态廊道|环境DNA|鱼类|长江口 |
| DOI：10.3969/J.ISSN.2095-4972.20240318003 |
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| 基金项目:上海市“科技创新行动计划”社会发展科技攻关项目（22DZ1202600）；上海市环境监测中心委托项目（HT2024306A2） |
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| Study of the biological connectivity of land-sea continuum: a case study of fishes in Shanghai waters of the Yangtze River Estuary |
| LI Changwen,XIAO Ya,JIANG Xiaodong |
| (School of Life Sciences，East China Normal University，Shanghai 200241，China) |
| Abstract: |
| The land-sea continuum is a transitional zone connecting terrestrial and sea ecosystems and the connectivity has a significant impact on the migration of organisms，while description and quantification of the land-sea continuum is still being explored. Based on fish diversity data obtained by amplified a portion of the V5 high-variable region of the 12S rRNA gene in fish mitochondria using universal primers targeting vertebrates，we developed a method to quickly assess connectivity of the land-sea continuum. The method is used to estimate the comprehensive index of biological connectivity (CIBC) from the Beta diversity index between adjacent cloud computing sites. The value ranges from 0 to 1 and the higher the value means a better connectivity. In October 2023，eDNA technology was successfully used to detect 117 species fish of 86 genera in 35 families of 21 orders from the main streams and tributaries of Shanghai waters in the Yangtze River Estuary where the numbers of fish in the tributaries were more than that in the main stream. Alpha diversity analysis shows that fish communities in tributaries are richer than those in main streams，but less diverse than those in main streams. The CIBC values of Cyprinidae show that the connectivity of trunk branches is generally fine while the values of Xenocypridae are better at the upstream and downstream. The values of Acheilognathidae are relatively good at the upstream while the values of Gobiidae are also high at the middle and upper reaches. The overall CIBC values of the fish community indicated a good connectivity in the main stream，but it is poor in the lower reaches near the Yangtze River Estuary and it various significantly in the tributaries. Overall connectivity in main stream is better than that of the tributaries. The method developed in this study can provide new insights for the study of land-sea continuum connectivity and contribute to the ecological restoration and integrated management for ecological corridors in Shanghai waters of the Yangtze River Estuary. |
| Key words: land-sea continuum|connectivity|ecological corridor|environmental DNA|fish|Yangtze River Estuary |
