1. Joe’s Bayou Repeated Observation

2. So……... What are we measuring? Water Quality Parameters (measureable physical properties that determine the health of the water.) We will be collecting quantitative data. (That means data with a number in it.)

3. Dissolved Oxygen Dissolved oxygen is the oxygen gas that fits in between the water molecules in the bayou. Fish breathe dissolved oxygen by absorbing it through their gills. Colder water contains more dissolved oxygen than warmer water. As organisms die and decompose, they also use up the DO in the water.

4. Why do we measure DO? Water must have an adequate amount of dissolved oxygen to support life. Joe’s Bayou should have a dissolved oxygen amount between 6.1 and 9.0 ppm (parts-per-million).

5. pH pH is a measure of how acidic the water is. The pH scale goes from 1 to 14 with 7 being neutral. The lower the number the more acidic the water is. Every increase of one on the scale is actually an increase of 10 times more acid. A pH of 5 is 10 times more acid than a pH of 6.

6. Why do we measure pH? Most plants and animals cannot survive in water that has a pH less than 5. It’s too acidic. Joe’s Bayou needs a pH between 7 and 8 to be healthy.

7. Turbidity Turbidity is a measure of how clear the water is. Suspended solids (particles floating in the water) can block the sun’s light from reaching the underwater sea grasses that baby organisms use for protection. Suspended solids can also raise water temperature which reduces the DO.

8. Why do we measure Turbidity? High turbidity can lower the amount of dissolved oxygen in the water and reduce the sea grasses that juvenile organisms need. A good measurement is between 0 and 15 jtu (Jackson turbidity units).

9. Salinity Salinity is a measure of how much salt is in the water. Animals and plants require certain salinity levels to survive. Too much or too little salt can cause them to get sick or die. As salinity increases DO decreases. As salinity decreases, DO increases.

10. Why do we measure salinity? Animals and plants require certain salinity levels to survive. Joe’s Bayou should have a salinity between 1 and 30 ppt (parts-per- thousand).

11. Temperature Temperature is a measure of the kinetic energy of an object (how fast its particles are moving). Higher temperatures can increase plant growth which is good, but when there is too much plant growth it causes a decrease in DO when the plants die. The higher the temperature the less DO because the gas particles escape from the surface of the water. The water heats up and cools down much slower than the land does.

12. Why do we measure temperature? Temperature has a big effect on the amount of DO in the water

13. Nitrates Nitrates are essential for plant growth but too many nitrates is a bad thing. Too many nitrates can cause too much plant growth which can reduce the amount of DO available in the water. Nitrates are caused by fertilizers and animal and human wastes.

14. Why do we measure nitrates? Nitrates can increase temperature, decrease DO, and indicate pollution. A good measurement for nitrates at Joe’s Bayou is 0 (zero).

15. Phosphates Phosphates are also essential for plant growth but, just like nitrates, too many phosphates is a bad thing. Too many phosphates can cause too much algal blooms (lots and lots of algae  ). Phosphates are found in fertilizers, rocks, and soil.

16. Phosphates can increase temperature, decrease DO, decrease the amount of sunlight getting through the water, and indicate pollution. A good measurement for phosphates at Joe’s Bayou is 0 (zero). Why do we measure phosphates?