AP BIOLOGY

Detailed explanation-1: -Explanation: If Cleo wants to increase the amount of nitrogen in the soil, she must plant nitrogen-fixing plants. Example: Soybean, pea plants, pulse, pigeon pea and etc. These plants roots contain nitrogen-fixing bacterias like nostoc, oscillatoria which helps in the fixation of nitrogen in the soil.

Detailed explanation-2: -to increase nitrogen in soil, cleo should try making compost using vegetables, coffee grounds, and other food waste, which will enrich your soil with nitrogen when you use it to garden with. You can also plant more legume plants, like peas, alfalfa, and beans, which produce nitrogen as they grow.

Detailed explanation-3: -Plants get the nitrogen that they need from the soil, where it has already been fixed by bacteria and archaea. Bacteria and archaea in the soil and in the roots of some plants have the ability to convert molecular nitrogen from the air (N2) to ammonia (NH3), thereby breaking the tough triple bond of molecular nitrogen.

Detailed explanation-4: -Plants cannot themselves obtain their nitrogen from the air but rely mainly on the supply of combined nitrogen in the form of ammonia, or nitrates, resulting from nitrogen fixation by free-living bacteria in the soil or bacteria living symbiotically in nodules on the roots of legumes.