RT info:eu-repo/semantics/article T1 Spatial variability, structure and composition of crustose algal communities in Diadema africanum barrens A1 Afonso Carrillo, Julio A1 Sangil, Carlos A1 Sansón Acedo, Marta A1 Díaz Villa, Tania A1 Hernández, José Carlos A1 Clemente, Sabrina A2 BotánicaEcología y Fisiología Vegetal A2 Botánica Marina AB Crustose algal communities were studied inDiadema africanum urchin barrens around Tenerife (Canary Islands, NE Atlantic). A hierarchical nested samplingdesign was used to study patterns of community variabilityat different spatial scales (sectors, three sides of the island;sites within each sector, 5–10 km apart; stations withineach site, 50–100 m apart). Although noncrustose speciescontributed the most to community richness, cover wasdominated by crustose forms, like the coralline algae Hydrolithon farinosum, H. samoe¨nse, H. onkodes, Neogoniolithon orotavicum and N. hirtum, and the phaeophyceanPseudolithoderma adriaticum. The structure of thesecommunities showed high spatial variability, and we founddifferences in the structure of urchin barrens when compared across different spatial scales. Multivariate analysisshowed that variability in community structure was relatedto the five environmental variables studied (wave exposure,urchin density, substrate roughness, productivity anddepth). Wave exposure was the variable that contributedmost to community variability, followed by urchin densityand substrate roughness. Productivity and depth had limited influence. The effects of these variables differed depending on the spatial scale; wave exposure and productivity were the main variables influencing communitychanges at the largest scale (between different sectors ofthe island), while D. africanum density, roughness anddepth were the most influential at medium and small scales. YR 2014 FD 2014 LK http://riull.ull.es/xmlui/handle/915/28315 UL http://riull.ull.es/xmlui/handle/915/28315 LA en DS Repositorio institucional de la Universidad de La Laguna RD 28-mar-2024