Need definitions for these
ammonia
inert
nitrates
limiting nutrient s
aturation
eutrophication
nitrification
denitrification

Ammonia=a colorless gas with a characteristic pungent smell. It dissolves in water to give a strongly alkaline solution.

Inert=lacking the ability or strength to move.

Nitrates=a salt or ester of nitric acid, containing the anion NO3− or the group —NO3.

Limiting nutrient S=Nitrogen and phosphorus are frequently called “limiting nutrients.” This means that at any given time, one or the other of these nutrients may be the hardest nutrient for a plant to acquire and therefore be the only nutrient that is limiting the plant's growth.
saturation=the state or process that occurs when no more of something can be absorbed, combined with, or added. The degree or extent to which something is dissolved or absorbed compared with the maximum possible, usually expressed as a percentage.

Eutrophication=excessive richness of nutrients in a lake or other body of water, frequently due to runoff from the land, which causes a dense growth of plant life and death of animal life from lack of oxygen.
 Nitrification=Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The transformation of ammonia to nitrite is usually the rate limiting step of nitrification. Nitrification is an important step in the nitrogen cycle in soil.

Denitrification=Medical Definition of denitrification. : the loss or removal of nitrogen or nitrogen compounds; specifically : reduction of nitrates or nitrites commonly by bacteria (as in soil) that usually results in the escape of nitrogen into the air.

Independent variable is something that is changed in a experiment.