Publication details.


Author(s):F. Tuya, M.A. Viera-Rodríguez, R. Guedes, F. Espino, R. Haroun, J. Terrados
Title:Seagrass reponses to nutrient enrichment depend on clonal integration, but no flow-on effects on associated biota
JCR Impact Factor:2.64

We determined physiological and morphological responses of the seagrass Cymo -
docea nodosa and associated epiphytes and epifauna to water column nutrient enrichment, and
investigated whether responses were modulated by the clonal integration of the seagrass. Nutrient
levels were elevated, relative to ‘ambient’ plots, in ‘large’ (~10 to 100×) and ‘moderate’ (~5 to
10×) enrichment plots, in a seagrass meadow off the south coast of Gran Canaria. Clonal integration
was severed in half the plots, isolating them from adjacent shoots. Seagrass shoot density,
above-ground biomass and leaf surface were lower in fertilized than ambient plots when clonal
integration was severed. In the plots where clonal integration was maintained, no differences in
shoot density were observed between fertilized and ambient plots, while differences in aboveground
biomass and leaf surface were exclusively observed between ‘large’ enrichment and
‘ambient’ plots. Seagrass above-ground tissues accumulated P, but not N, when clonal integration
was maintained. The N content, but not P content, of below-ground parts increased with fertilization.
The content of soluble sugars in seagrass tissues decreased under nutrient enrichment; this
decay was, however, buffered when clonal integration was maintained. Grazing bites on leaves
increased with nutrient enrichment regardless of the clonal integration. Epiphytic loads increased
at elevated nutrient levels irrespective of the clonal integration. The abundance and richness of
epifauna were larger on ‘moderate’ relative to ‘ambient’ and ‘large’ enrichment plots, independently
of clonal integration. In conclusion, while the physiological and morphological responses of
C. nodosa to nutrient enrichment depended on the maintenance of clonal integration, flow-on
effects on epiphytes and epifauna were independent of the clonal integration of the seagrass.

Related staff

  • Jorge Terrados Muñoz