1. LILLY THAYER BOT 437 SPRING 2009 Algal Community Succession

2. 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

3. Light, temp., day length, nutrients, previous species, etc.

4. 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?

5. Study 2° succession in natural habitat  Glover’s Reef, Belize Imitates pollution with fishing  Only small herbivorous fish Distinguish effects of N and P

6. 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

7. Results “No significant fertilization effect on algal biomass” (McClanahan, 2007)

8. 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

9. 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)

10. 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.