What is the nutrition that vegetables absorb from the roots?

In the soil, there are “organic nitrogen” and “inorganic nitrogen” absorbed by vegetables.
Vegetables absorb inorganic nitrogen decomposed by microorganisms, which is organic matter in the soil (organic fertilizer, plant residues, carcasses of insects, etc.)
There are two types of inorganic nitrogen, “ammonia nitrogen” and “nitrate nitrogen”.
Ammonia nitrogen is is converted to nitrate nitrogen by the ammonia-forming bacteria in the soil.
Most vegetables absorb this nitrate nitrogen as a nutrient from their roots.
The absorbed nitrate nitrogen is converted to ammonia nitrogen in the vegetable body and then synthesized into protein.

In fact, it is becoming clear that vegetables absorb nutrients not only with nitrate nitrogen but also with ammonia nitrogen.
Paddy rice and lotus root grow in water.
It is known that vegetables that grow in little oxygen environment absorb ammonia nitrogen as nutrients.