Final answer:
Agriculture contributes to the collapse of lake ecosystems by overusing nitrogen fertilizers, leading to algal blooms which deplete oxygen and cause eutrophication, ultimately creating dead zones in water bodies.
Step-by-step explanation:
Agriculture significantly impacts lake ecosystems through a process called eutrophication, which is primarily due to the runoff of excess nitrogen and phosphorus from fertilizers. Here's how agriculture can contribute to the collapse of lake ecosystems in the correct order:
Crop plants do not use up all the applied nitrogen fertilizers.
Excess nitrogen fertilizer leaches from agricultural soil to nearby bodies of water.
Algae that were formerly limited by Nitrogen grow in excess, also known as an algal bloom.
Algae blooms use up Oxygen in the environment, leading to a decrease in dissolved oxygen levels.
Eutrophication creates dead zones in which fish and other large organisms cannot survive.
These steps describe a chain reaction that starts with the overuse of fertilizers in agricultural practices and results in the depletion of oxygen in water bodies, which is detrimental to aquatic life and creates dead zones where life cannot be sustained.