Freshwater Biome Estuaries Nitrogen Cycle Aquatic Biomes Freshwater

Freshwater Biome, Estuaries, Nitrogen Cycle

Aquatic Biomes • Freshwater • Marine • Estuaries

Freshwater Biomes • Rivers, streams, lakes • Organisms: fish, frogs, algae • Often surrounded by a variety of plants.

Estuaries • Area where fresh and salt water mix (where rivers enter ocean) • Examples: lagoons, mangrove swamps • Many species of plants, fish, crabs, shrimp, and birds live here. • “Nurseries of the Sea” – many species reproduce or raise young in estuaries.

Nitrogen Cycle Ø 1. Nitrogen is removed from the atmosphere through nitrogen fixation (bacteria convert nitrogen gas to nitrates) Ø 2. Plants use nitrates to make proteins. Ø 3. Animals get nitrogen by eating plants (or animals that ate nitrogen in atmosphere plants) animals plant nitrates nitrogen-fixing nitrifying bacteria in decomposers bacteria roots ammonification nitrites nitrogen-fixing bacteria in soil ammonium nitrifying denitrifying bacteria

Nitrogen Cycle (cont. ) Ø 4. Animal waste and dead plant/animal matter are decomposed by bacteria, nitrogen is returned to the soil. Ø 5. Bacteria return nitrogen to atmosphere through the process of denitrification. nitrogen in atmosphere animals plant nitrates nitrogen-fixing nitrifying bacteria in decomposers bacteria roots ammonification nitrites nitrogen-fixing bacteria in soil ammonium nitrifying denitrifying bacteria

Nitrogenfrom Nitrogen is Nitrogen dead Fixation: Nitrogen excreted animals plants andby animals isbroken taken from the in the form of urine is down by atmosphere and or feces returning bacteria fixed as to nitrates by nitrogen the soil bacteria Denitrification: Nitrogen is returned to the atmosphere by bacteria Nitrogen Cycle Nitrates are absorbed by plants from the soil and used to build proteins Plants are eaten by consumers and nitrogen is taken up

Eutrophicat ion • Increase of phosphorus and nitrogen http: //www. youtube. com/ watch? v=6 LAT 1 g. LMPu 4 concentrations in bodies of water, usually from run off • Causes algal blooms • Leads to lack of oxygen in body of water