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A pond has a minnow population of 20000 that is increasing at a rate of 5%

per year. The minnows' algae food supply is decreasing so that it supports
750 less minnows each year. How is the population of minnows growing,
and how is the supply of algae declining?

User Ashoka
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2 Answers

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Final answer:

The minnow population increases by 5% annually but faces a declining algae food source, decreasing by 750 each year. Nitrogen and phosphorus cause algal blooms, affecting oxygen levels in the pond, potentially impacting minnow survival.

Step-by-step explanation:

The minnow population in the pond is initially 20,000 and is increasing at a rate of 5% per year. However, the minnow's food source, algae, is decreasing because it supports 750 fewer minnows each year.

Nitrogen and phosphorus are important nutrients that limit phytoplankton growth. A large input of these nutrients can cause algal blooms, which can lead to severe reductions in water oxygen levels when they decompose. This can be detrimental to organisms like minnows that require oxygen to survive.

The minnows' population will, therefore, be affected by both the increase due to reproduction and the decline in food resources. Over time, this could lead to a decrease in minnow population if the loss of algae becomes too severe and the pond's ecosystem becomes imbalanced.

User Andersra
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20000x.05= 1000 added minnows per year, with the algae decline, we loose 750 minnows per year. 250 minnows are added every year. The rate 5% every year would be exponential growth, and the decline of 750 minnows per year is a result of a negative constant (not exponential decline.)
User Amrender Singh
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