Trophodynamic effects of climate change-induced alterations to primary production along the western Antarctic Peninsula

Abstract

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 569:37-54 (2017) - DOI: https://doi.org/10.3354/meps12100 Trophodynamic effects of climate change-induced alterations to primary production along the western Antarctic Peninsula Paul Mark Suprenand1,2,*, Cameron H. Ainsworth1 1University of South Florida, College of Marine Science, 140 7th Avenue South, St. Petersburg, FL 33701, USA 2Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236, USA *Corresponding author: psuprenand@mote.org ABSTRACT: Under climate change, alterations in primary production and concomitant changes in community dynamics are expected in many marine ecosystems. We used an Ecopath with Ecosim (EwE) marine ecosystem model of the western Antarctic Peninsula to simulate effects on the food web based on proposed changes in the primary production regime expected as a result of climate change. Scenarios for trophic modeling are based on published results from coupled high-resolution regional ocean sea-ice and ice-shelf models, which consider alterations in water circulation from westerly wind intensification, increases in circumpolar deep water upwelling, iron upwelling, and decreases in sea-ice extent. Modeling scenarios included 6, 15, and 41% increases in phytoplankton production with equivalent percentage decreases in ice algal production, and 1 scenario with 15% increase for phytoplankton with no change for ice algae. These scenarios were achieved through linear forcing functions within the EwE software. We framed ecosystem changes in terms of biomass, species diversity, mean trophic level, trophodynamics, and network metrics. Simulations revealed that in each scenario, mean trophic level increased, species diversity generally decreased, and energetic pathways were reorganized. Modeled changes in the planktonic invertebrate assemblage include changes in 2 key competitors, krill and salps. For example, model results predict declines in krill biomass with concomitant increases in salp biomass. In all scenarios that assumed a negative change in ice-algae production rates due to sea-ice habitat loss, whale, seal, and penguin populations were negatively affected. Changes in ecosystem structure in this sensitive region may serve as an indicator of changes expected in the Southern Ocean. KEY WORDS: Antarctic warming · Trophodynamics · Climate change · Antarctic Peninsula · Ecosystem model · Ecopath with Ecosim Full text in pdf format Supplementary material PreviousNextCite this article as: Suprenand PM, Ainsworth CH (2017) Trophodynamic effects of climate change-induced alterations to primary production along the western Antarctic Peninsula. Mar Ecol Prog Ser 569:37-54. https://doi.org/10.3354/meps12100 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 569. Online publication date: April 07, 2017 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2017 Inter-Research.