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

• Published in: PloS one Vol. 10; no. 3; p. e0120837
• Main Authors: Strain, Elisabeth M A, van Belzen, Jim, van Dalen, Jeroen, Bouma, Tjeerd J, Airoldi, Laura
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 25.03.2015; Public Library of Science (PLoS)
• Subjects: Algae; Anthropogenic factors; Aquatic habitats; Beaches; Canopies; Climate Change; Coastal environments; Conservation; Cystoseira barbata; Ecology; Ecosystem; Ecosystems; Experiments; Exposure; Global climate; Habitats; High temperature; Human influences; Laminaria; Laminariales; Load; Management; Mediterranean Sea; Nutrient concentrations; Nutrient loading; Nutrients; Ochrophyta; Phaeophyceae - physiology; Phaeophyta; Pollution load; Resilience; Sea surface temperature; Sediment load; Sediment transport; Sedimentation & deposition; Sediments; Sediments (Geology); Soil erosion; Soil testing; Stress, Physiological - physiology; Surface temperature; Survival; Temperature; Temperature effects; Water Quality; Mediterranean Sea; Italy; Netherlands; Adriatic Sea
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0120837

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.