Plankton lifeforms as a biodiversity indicator for regional-scale assessment of pelagic habitats for policy

Abstract

Plankton are sensitive indicators of change and, at the base of marine food webs, they underpin important ecosystem services such as carbon sequestration and fisheries production. In the UK and the Northeast Atlantic region, change in plankton functional groups, or 'lifeforms', constructed based on biological traits, is the formally accepted policy indicator used to assess Good Environmental Status (GES) for pelagic habitats under the Marine Strategy Framework Directive (MSFD: 2008/56/EC). To identify changes in UK pelagic habitats, plankton lifeforms, were used from diverse UK data sets collected by different methods, including plankton sampling by nets, water bottles, integrating tube samplers, and the Continuous Plankton Recorder. A Plankton Index approach was used to identify change in plankton lifeforms. This is the first time that the pelagic plankton community has been assessed on a UK-wide scale and forms the foundation of the UK's 2020 MSFD Assessment for pelagic habitat biodiversity and food webs. This approach revealed that some of the plankton lifeforms used in the assessment displayed spatiallyvariable changes during the past decade. Assessing plankton community change using a common indicator at the UK scale for the first time is a significant step towards evaluating GES for European seas. Determining GES for pelagic habitats, however, is a challenging process, with additional work required to interpret the assessment results and to identify causation of the changes observed.

Seasonal and Temporal Drivers Influencing Phytoplankton Community in Kuwait Marine Waters: Documenting a Changing Landscape in the Gulf

“…This was done by grouping the data into diatom and dinoflagellate lifeform groups. Lifeforms are aggregations of taxa that group together individual taxa with a similar functional role which are less likely to experience the extreme seasonal fluctuations of single species indicators and their use increases spatial intercomparability (McQuatters-Gollop et al, 2019). Shifts in community structure based on lifeforms were identified by applying the Plankton Index (PI) approach, the details of which are described elsewhere (Tett et al, 2007(Tett et al, , 2013Gowen et al, 2015).…”

Utilizing Eutrophication Assessment Directives From Transitional to Marine Systems in the Thames Estuary and Liverpool Bay, UK

“…A protocol is being developed by the wider research community to use PI values to identify key stressors (McQuatters-Gollop et al, 2019). Low PI values observed here, indicating changes in plankton community in terms of the diatom and dinoflagellate lifeforms, appear to be driven in Liverpool Bay by increasing counts of dinoflagellates, especially during winter months, and in the Thames by increasing summertime dinoflagellate counts.…”

“…The outcomes of the lifeform tool (Tett et al, 2008;McQuatters-Gollop et al, 2019) show that the phytoplankton communities in many of the assessment areas have changed in relation to the diatom and dinoflagellate counts. Whilst many of the assessment areas show a change in the PI value, signifying a change between the reference period (2013-2015) and the assessment period (2006)(2007)(2008)(2009)(2010)(2011)(2012), there is not a statistically significant linear trend over the assessment period.…”

Lifeform indicators reveal large‐scale shifts in plankton across the North‐West European shelf

“…This study focuses on three pairs of key lifeforms—diatoms and dinoflagellates (representing the phytoplankton community), large and small copepods, and holoplankton and meroplankton (representing the zooplankton community). Here we map the dynamics of each lifeform individually, but when interpreted in pairs, the absolute and relative abundances of the lifeform pair can indicate change in key aspects of ecosystem function (McQuatters‐Gollop et al, 2019). These lifeforms are well sampled, and their associated functional traits can be unambiguously applied to the individual taxa identified during sample analysis.…”

“…In response to the multiple policy drivers for an ecosystem approach to management (Apitz, Elliott, Fountain, & Galloway, 2006), a concerted effort has been undertaken to develop plankton indicators for reporting on status and trends. An indicator based on change in the balance of ‘plankton lifeforms’ is used to assess lower trophic levels in the North‐East Atlantic and monitor progress towards environmental targets (McQuatters‐Gollop et al, 2019). Plankton lifeforms are groupings of plankton taxa based on shared functional traits (e.g.…”