The adaptive capacity of multitrophic plankton communities in a changing ocean

• Applicant: Professor Dr. Agostino Merico
• Subject Area: Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions ; Oceanography
• Term: from 2014 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 257408949

There is broad consensus in the scientific community that the worlds climate is changing at an unprecedented rate. Evidence is accumulating on the ecological consequences of the changing climate. In the aquatic realm, for example, such consequences have involved shifts in the phenology of phytoplankton and zooplankton and reorganizations of phytoplankton community compositions towards species with smaller cell sizes. In a changing environment, ecological communities need to adapt their distribution of phenotypes so that the average fitness increases and the community can thrive under the new environmental conditions. Adaptation can work through a change in the genetic composition (e.g. microevolution) or through different forms of phenotypic plasticity. Whether such mechanisms will play a role in the real ocean, for example by making phytoplankton communities (and therefore the marine foodweb) more resilient to changing environmental conditions, is currently unclear. We propose here a project aiming at integrating a variety of laboratory data and field observations, including those acquired within DynaTrait, into a novel trait-based modelling framework. This modelling framework is based on the adaptive dynamics of phytoplankton cell-size and, critically, on a trade-off emerging from relationships between phytoplankton cell size and 1) phytoplankton nutrient uptake, 2) zooplankton grazing, and 3) phytoplankton sinking. The adaptive capacity of the phytoplankton community is captured by a mechanism of trait variation associated to reproduction so that trait variance is maintained as traits are diffused through subsequent generations of species. With this tool we plan to investigate how shifts in phytoplankton community composition and phenotypic diversity impact the foodweb dynamics of two contrasting regions (temperate and tropical) of the Atlantic Ocean under a number of environmental shocks, disturbances, and future scenarios. Ultimately, our project represents an opportunity to translate the knowledge aquired within the DynaTrait programme into the context of a real ocean environment.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1704: Flexibility Matters: Interplay Between Trait Diversity and Ecological Dynamics Using Aquatic Communities as Model Systems (DynaTrait)
• International Connection: Japan, Spain
• Participating Persons: Professor Dr. Lutz Becks; Dr. Gunnar Brandt; Professor Dr. Helmut Hillebrand; Professor Dr. Emilio Maranon; Dr. Lan Smith