Concept explainers
Eutrophication is a process whereby lakes, estuaries, or slow-moving streams receive excess nutrients that stimulate excessive plant growth. This enhanced plant growth, often called an algal bloom, reduces dissolved oxygen in the water when dead plant material decomposes and can cause other organisms to die. Nutrients can come from many sources, such as fertilizers; deposition of nitrogen from the atmosphere; erosion of soil containing nutrients; and sewage treatment plant discharges. Water with a low concentration of dissolved oxygen is called hypoxic. A biosystems engineering models the algae growth in a lake. The concentration of algae (C), measured in grams per milliliter (g/ml], can be calculated by
Where
Co = initial concentration of algae [?]
K= multiplication rate of the algae [?]
r= estimated nutrient supply amount [mg of nutrient per mL of sample water]
t= time [days]
- a. For the exponential model shown, list the value and units of the parameters m and b . You do not need to simplify any units. Recall that an exponential model has the form: y=bemx .
- b. What are the units on the multiplication rate of the algae (k)?
- c. If the algae are allowed to grow for 10 days with an estimated nutrient supply of 3 milligrams of nutrient per milliliter of water sample, what is the multiplication rate of the algae (k)?
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