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Algal Community Succession. Lilly Thayer Bot 437 Spring 2009. Ecological Succession : Changes in the species composition. often predictable and usually follows an orderly stepwise pattern Primary Succession : No living organisms lava flow or glacial ice-scour.
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Algal Community Succession Lilly Thayer Bot 437 Spring 2009
Ecological Succession: Changes in the species composition. • often predictable and usually follows an orderly stepwise pattern • Primary Succession: No living organisms • lava flow or glacial ice-scour. • Secondary Succession: Life, or potential life • wildfire, deforestation, or hurricane
Effect of Fertilization • “Short-term… effects on algal colonization, abundance, and species composition” of nitrogen and phosphorous fertilizers. (McClanahan, 2007) • Past studies show increased: • Photosynthesis • Growth rates • Biomass • Phosphorous most limiting?
Study 2° succession in natural habitat • Glover’s Reef, Belize • Imitates pollution with fishing • Only small herbivorous fish • Distinguish effects of N and P
Study Design • 4 treatments (N, P, N+P, Control) • Plates of dead coral • Tests 2° succession • Record small fish herbivory rates • Excluded large herbivorous fish and urchins • Record algal biomass, plate cover, and diversity
“No significant fertilization effect on algal biomass” (McClanahan, 2007) Results
Results… • “Control treatment had more taxa than fertilized treatments” (McClanahan, 2007) • Pure P least diversity • Turf algal cover • Only type to respond to fertilization • Lowest in pure P • Did not increase with increasing N • Co-limitation ○= Control □ = N + P ◇ = P △ = N
Conclusion • Effect of high P similar to effect of high herbivory • Gives competitive edge to cyanobacteria • “Taxa-specific responses to the two nutrients but… nitrogen and phosphorous are co-limiting to turf algal cover” (Mc Clanahan, 2007) • More diversity in mixed N and P treatments than pure • “Large imbalance in micronutrients ratios… will reduce biodiversity more than just increased [N]” (McClanahan, 2007)
Works Cited Aguilara, Moisés; Navarrete, Sergio. 2007. Effects of Chiton granosus (Frembly, 1827) and other molluscan grazers on algal succession in wave exposed mid-intertidal rocky shores of central Chile. Journal of Experimental Marine Biology and Ecology. 349: 84-98. Bruce, Louise, et. al. 2009. The role of zooplankton in the ecological succession of plankton and benthic algae across a salinity gradient in the Shark Bay salt ponds. Hydrobiologia. 626: 111-128. Fricke, Anna, et.al. 2007. Natural succession of macroalgal-dominated epibenthic assemblages at different water depths and after transplantation from deep to shallow water on Spitsbergen. Polar Biology. 31: 1191-1203. Kraufvelin, Patrik, et. al. 2007. Winter colonisation and succession of filamentous macroalgae on artificial substrates and possible relationships to Fucus vesiculosus. Estuarine, Coastal and Shelf Science. 72: 665-674. McClanahan, T.R., et. al. 2007. Effect of nitrogen, phosphorous, and their interaction on coral reef algal succession in Glover’s Reef, Belize. Marine Pollution Bulletin. 54: 1947-1957. Olabarria, C., et. al. 207. Succession of macrofauna on macroalgal wrack of an exposed Sandy beach: Effects of patch size and site. Marine Environmental Research. 63: 19-40. Petraitis, Peter; Dudgeon, Steve. 2005. Divergent succession and implications for alternative states on rocky intertidal shores. Journal of Experimental Marine Biology and Ecology. 326: 14-26.