Response of phytoplankton community to nutrient quality and quantity change in Maryland/Virginia Coastal Bays
ASLO Aquatic Sciences Meeting, Granada, Spain
Coastal lagoons are characterized as shallow water bodies that are separates from the ocean by barriers. Differences in the quality of the nutrient pool, and the resident phytoplankton community can lead to different types of algal blooms in coastal lagoons. An experiment was conducted to quantify the effect of different types of nutrient enrichments in the phytoplankton community in temperate lagoons. Ten liters cubitainers containing water from Maryland/Virginia Costal Bays were exposed to six nutrient treatments and a control. Experimental cubitainers were enriched with different nitrogen forms and N:P ratios, as follow: Ammonium (NH4+) 16µM; nitrate (NO3-) 16µM; Dissolved organic nitrogen (DON) 16µM; ammonium 16µM + phosphate (PO4-3) 1µM; nitrate 16µM + phosphate 1µM and dissolved organic nitrogen 16µM + phosphate 1µM. All cubitainers were incubated on the field during 48 hours. This experiment was conducted twice during summer 2014. Nanoplankton community dominated when exposed to NH4+ and NH4+:PO4-3, while prokaryotes only increased when exposed to ammonium. Pico-eukaryotes did not showed any dominance on any treatments. Results suggested that enrichment responses of phytoplankton community in lagoon ecosystems are diverse.