Presentation on theme: "Dissolved Oxygen The Good Gas. Photosynthesis: Your one-stop shop for all of your oxygen needs! Carbon Dioxide (from air) Water (from ground) Oxygen (to."— Presentation transcript:
Photosynthesis: Your one-stop shop for all of your oxygen needs! Carbon Dioxide (from air) Water (from ground) Oxygen (to air) Carbohydrate (plant material) Solar energy + 6CO 2 + 6H 2 O → C 6 H 12 O 6 + 6O 2 Happy Rays of Sunshine
CO 2 O2O2 Aquatic plants and phytoplankton (single cell floating plants) release oxygen into the water as a product of photosynthesis
Phytoplankton (single cell plants) – are the base of the aquatic food web and provide most of the aquatic oxygen.
Submerged aquatic plants can provide shelter for young fish as well as house an abundant food supply.
Hypoxic Anoxic Normoxic Habitat Classification Based on DO Concentration 0 – 0.2 mg/L 0.2 – 2 mg/L > 2 mg/L Most fish need oxygen levels > 2.0 mg/L
Respiration: How we, the animals, use oxygen (and plants too!) C 6 H 12 O 6 + 6O 2 → 6CO 2 + 6H 2 O + energy (in form of ATP) Carbohydrate + Oxygen Carbon Dioxide + Water + Energy Oxygen in CO 2 and H 2 O out Previous Meal Carbohydrate in Energy out
CO 2 : A Soluble Gas Too! H2OH2O H2OH2O H2OH2O H2OH2O O2O2 H2OH2O H2OH2O H2OH2O O2O2 O2O2 O2O2 O2O2 O2O2 H2OH2O O2O2 H2OH2O CO 2
C 6 H 12 O 6 Solar Energy Heat Energy Biomass (g/m 2 /yr) O2O2 Chemical Energy (ATP) Photosynthesis Respiration Biological Production and Consumption of Oxygen
SunriseNoonSunsetMidnight CO 2 +H 2 O H 2 CO 3 H + +HCO 3 - 2H + +CO 3 - An increase in CO 2 causes an increase in H + pH SunshineMoonshine pH Level
Decomposition – Not good for DO Decomposer organisms (mainly bacteria) consume oxygen –Sometimes consume oxygen faster than plants can produce it, even during the middle of the day! A sudden increase in organic matter (think leaf litter) can create a spike in decomposition activity – especially if it is hot –Hurricanes not only add organic matter to our waterways, but also stir up the sediment. –Can cause fish kills!!
Abiotic Factors That Affect DO Concentration Temperature Water Clarity Current Velocity (Flow) Wind Cloud Cover
Temperature The warmer water is, the less DO it can hold –Think about opening a coke bottle after it sat a few hours on the dash of your car in August. Excess DO evaporates into the atmosphere! 100% DO Saturation 0 2 4 6 8 10 12 14 16 18 20 05101520253035 Temperature (C) 100% Saturation Lavel
Oxygen > 100% Saturation Oxygen < 100% Saturation Oxygen diffuses out of water column Oxygen diffuses into water column Water Column Atmosphere Oxygen Can Diffuse Out of or Into the Water Column