Spatial segregation of calanoid and cyclopoid copepods in the coastal waters of the Yellow Sea

Spatial segregation of calanoid and cyclopoid copepods in the coastal waters of the Yellow Sea | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Spatial segregation of calanoid and cyclopoid copepods in the coastal waters of the Yellow Sea Dai Liu, Zhonghua Cai, Kezhen Ying, Hui Liu, Hongsheng Bi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7693937/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Understanding the mechanisms that drive ecological separation among species is essential for explaining biodiversity patterns, especially in marine systems characterized by spatial heterogeneity. This study explores the distributional dynamics of two dominant copepod groups, calanoids and cyclopoids, in the coastal waters of the Yellow Sea, using high-resolution in situ data collected using the PlanktonScope underwater imaging system. We analyzed their horizontal and vertical distribution patterns, the degree of spatial overlap, and the environmental factors influencing these patterns. Our results reveal a distinct horizontal separation between the two groups. Calanoid copepods constituted over 80% of the total copepod abundance within 30 km of the coastline, making them the dominant taxonomic group in nearshore waters. In contrast, cyclopoid copepods exhibited an inverse distribution pattern, becoming the predominant group in offshore waters beyond 30 km. This spatial boundary, aligned with coastal current patterns and temperature gradients, further points to temperature as a key environmental driver. Calanoid abundance increased in warmer waters (>18°C), whereas cyclopoid density declined linearly as temperatures rose from 14°C to 20°C. Chlorophyll a exhibited a negative correlation with individual body size, although the effect was weak. This pattern was primarily driven by the higher abundance of smaller individuals in the nearshore zone, where chlorophyll a concentrations were elevated. By integrating advanced plankton imaging with statistical modeling, this study demonstrates how physical and biological gradients interact to structure copepod communities in coastal ecosystems. These findings improve our understanding of species coexistence and ecological differentiation in dynamic marine environments. Copepod distribution PlanktonScope imaging Spatial separation Generalized additive models Full Text Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7693937","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":525845019,"identity":"5c9db7c6-0456-481c-add8-7fea3794363e","order_by":0,"name":"Dai Liu","email":"","orcid":"","institution":"Tsinghua Shenzhen International Graduate School","correspondingAuthor":false,"prefix":"","firstName":"Dai","middleName":"","lastName":"Liu","suffix":""},{"id":525845020,"identity":"f34b50e8-f1d3-4069-8448-7403fd8ea6a0","order_by":1,"name":"Zhonghua Cai","email":"","orcid":"","institution":"Tsinghua Shenzhen International Graduate 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