Question

Complete the sentences relating to the role humans play in the nitrogen and phosphorus cycles. Humans increase the production of _____ by burning fossil fuels. By increasing the use of _____, humans are also creating an increase in eutrophication. A) Oxygen; Nitrogen B) Nitrogen; Phosphorus C) Carbon dioxide; Phosphorus D) Methane; Nitrogen

Answer 1

Human activity releases nitrogen into the environment through the combustion of fossil fuels and the use of artificial fertilizers in agriculture. This can have significant impacts on Earth's ecosystems, including acid rain, greenhouse gas effects, and eutrophication.

Step-by-step explanation:

Human activity can release nitrogen into the environment by two primary means: the combustion of fossil fuels, which releases different nitrogen oxides, and by the use of artificial fertilizers in agriculture, which are then washed into lakes, streams, and rivers by surface runoff. Atmospheric nitrogen is associated with several effects on Earth's ecosystems including the production of acid rain (as nitric acid, HNO3) and greenhouse gas (as nitrous oxide, N₂O) potentially causing climate change. A major effect from fertilizer runoff is saltwater and freshwater eutrophication, a process whereby nutrient runoff causes the excess growth of microorganisms, depleting dissolved oxygen levels and killing ecosystem fauna.

Answer 2

Humans increase the production of nitrogen oxides through the burning of fossil fuels and increase eutrophication by the use of phosphorus-containing fertilizers, making the correct answers B) Nitrogen; Phosphorus.

Step-by-step explanation:

Humans influence the nitrogen and phosphorus cycles through various activities. Humans increase the production of nitrogen oxides by burning fossil fuels, which can lead to acid rain and climate change effects. By increasing the use of artificial fertilizers that contain phosphorus, humans are also creating an increase in eutrophication. The correct answers to complete the sentences are:

• Humans increase the production of Nitrogen by burning fossil fuels.
• By increasing the use of Phosphorus, humans are also creating an increase in eutrophication.

Therefore, the complete statements would be filled in as follows:

• Humans increase the production of Nitrogen by burning fossil fuels.
• By increasing the use of Phosphorus, humans are also creating an increase in eutrophication.

Thus, the correct answer is B) Nitrogen; Phosphorus.