Eelgrass (Zostera marina) Food Web Structure in Different Environmental Settings

PLoS One. 2016 Jan 11;11(1):e0146479. doi: 10.1371/journal.pone.0146479. eCollection 2016.

Abstract

This study compares the structure of eelgrass (Zostera marina L.) meadows and associated food webs in two eelgrass habitats in Denmark, differing in exposure, connection to the open sea, nutrient enrichment and water transparency. Meadow structure strongly reflected the environmental conditions in each habitat. The eutrophicated, protected site had higher biomass of filamentous algae, lower eelgrass biomass and shoot density, longer and narrower leaves, and higher above to below ground biomass ratio compared to the less nutrient-enriched and more exposed site. The faunal community composition and food web structure also differed markedly between sites with the eutrophicated, enclosed site having higher biomass of consumers and less complex food web. These relationships resulted in a column shaped biomass distribution of the consumers at the eutrophicated site whereas the less nutrient-rich site showed a pyramidal biomass distribution of consumers coupled with a more diverse consumer community. The differences in meadow and food web structure of the two seagrass habitats, suggest how physical setting may shape ecosystem response and resilience to anthropogenic pressure. We encourage larger, replicated studies to further disentangle the effects of different environmental variables on seagrass food web structure.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ecosystem
  • Environmental Monitoring
  • Food Chain*
  • Zosteraceae*

Grants and funding

This work was supported by the Nordic Seagrass Network, NordForsk project no. 9260, http://www.nordforsk.org/en/programmes/projects/nordic-seagrass-network. MH was supported by the Danish Council for Independent Research | Natural Sciences (FNU 12-127012) http://ufm.dk/en/research-and-innovation/councils-and-commissions/the-danish-council-for-independent-research/the-council-1/the-danish-council-for-independent-research-natural-sciences. DKJ received support from 1) the “Nutrient cocktails in the coastal zone of the Baltic Sea (COCOA) project http://cocoa.au.dk/ under “The joint Baltic Sea research and development programme (Art. 185) (BONUS)”, funded jointly by the EU 7th framework program (FP7) and the Danish Research Council; and 2) Development of innovative Tools for understanding marine biodiversity and assessing good environmental status “DEVOTES” http://www.devotes-project.eu/ under FP7 (contract #FP-308392). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.