Management of local stressors can improve the resilience of marine canopy algae to global stressors

PLoS One. 2015 Mar 25;10(3):e0120837. doi: 10.1371/journal.pone.0120837. eCollection 2015.

Abstract

Coastal systems are increasingly threatened by multiple local anthropogenic and global climatic stressors. With the difficulties in remediating global stressors, management requires alternative approaches that focus on local scales. We used manipulative experiments to test whether reducing local stressors (sediment load and nutrient concentrations) can improve the resilience of foundation species (canopy algae along temperate rocky coastlines) to future projected global climate stressors (high wave exposure, increasing sea surface temperature), which are less amenable to management actions. We focused on Fucoids (Cystoseira barbata) along the north-western Adriatic coast in the Mediterranean Sea because of their ecological relevance, sensitivity to a variety of human impacts, and declared conservation priority. At current levels of sediment and nutrients, C. barbata showed negative responses to the simulated future scenarios of high wave exposure and increased sea surface temperature. However, reducing the sediment load increased the survival of C. barbata recruits by 90.24% at high wave exposure while reducing nutrient concentrations resulted in a 20.14% increase in the survival and enhanced the growth of recruited juveniles at high temperature. We conclude that improving water quality by reducing nutrient concentrations, and particularly the sediment load, would significantly increase the resilience of C. barbata populations to projected increases in climate stressors. Developing and applying appropriate targets for specific local anthropogenic stressors could be an effective management action to halt the severe and ongoing loss of key marine habitats.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Climate Change
  • Ecosystem
  • Mediterranean Sea
  • Phaeophyceae / physiology*
  • Stress, Physiological / physiology*
  • Temperature
  • Water Quality

Grants and funding

The work was supported by the projects Observing, modelling and Testing synergies and TRade-offs for the adaptive management of multiple Impacts in coastal Systems (PRIN 2010–2011, MIUR); Innovative multi-purpose off-shore platforms: planning, design and operation (EU FP7-Ocean-2011, grant:288710), http://www.mermaidproject.eu/; THESEUS-Innovative technologies for safer European coasts in a changing climate (EU-FP7-ENV2009-1, grant:244104), http://www.theseusproject.eu/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.