Abstract
Large‐scale alterations in marine ecosystems as a response to environmental and anthropogenic pressures have been documented worldwide. Yet, these are primarily investigated by assessing abundance fluctuations of a few dominant species, which inadequately reflect ecosystem‐wide changes. In addition, it is increasingly recognized that it is not species identity per se, but their traits that determine environmental responses, biological interactions and ecosystem functioning. In this study, we investigated long‐term, spatio‐temporal variability in trait composition across multiple organism groups to assess whether functional changes occur in a similar way across trophic levels and whether shifts in trait composition link to environmental change. We combined extensive trait datasets with long‐term surveys (30–40 yr) of four organism groups (phytoplankton, zooplankton, benthic invertebrates and fish) in three environmentally distinct areas of a large marine ecosystem. We found similar temporal trajectories in the community weighted mean trait time‐series of the different trophic groups, revealing ecosystem‐wide functional changes. The traits involved and their dynamics differed between areas, concurrent with climate‐driven changes in temperature and salinity, as well as more local dynamics in nutrients and oxygen. This finding highlights the importance of considering both global climate, as well as local external drivers when studying ecosystem changes. Using a multi‐trophic trait‐based approach, our study demonstrates the importance of integrating community functional dynamics across multiple trophic levels to capture ecosystem‐wide responses which could, ultimately, help moving towards a holistic understanding, assessment and management of marine ecosystems.
Highlights
Marine communities worldwide are undergoing large-scale changes in response to environmental and anthropogenic impacts, including fishing, eutrophication, pollution and habitat destruction (Millennium Ecosystem Assessment 2005)
The observed ecosystem-wide restructuring consisted of communities with different trait composition in the early 1980s compared to the 2010s
There was a general decrease in the relative abundance of piscivorous fish and an increase of ambush feeder copepods at the expense of feeding-current zooplankton (Fig. 6)
Summary
Marine communities worldwide are undergoing large-scale changes in response to environmental and anthropogenic impacts, including fishing, eutrophication, pollution and habitat destruction (Millennium Ecosystem Assessment 2005). These alterations in community composition and species abundances can be linked to changes in species distributions (Pinsky et al 2011, Hiddink et al 2015), phenology (Edwards and Richardson 2004) and trophic mismatch (Durant et al 2007), and have been documented across a range of marine organism groups from primary producers to top predators (Poloczanska et al 2013). It is crucial to understand how environmental and anthropogenic pressures affect the commercially most important taxa (e.g. fish), but all organisms across trophic levels
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
