Where does potassium and nitrogen in the soil come from?

Question

Need help in this asap. thx alot.

Answer 1

There are cycles that maintain the amounts of potassium and nitrogen in the soil - though of course farmers and gardeners can add amendments that provide these elements, too. Much of the potassium comes from decaying material, plant and animal, which is taken up by the roots of the plant and used, until the plant is eaten (then its taken by the animal). When death comes to plant or animal, both decay and the potassium returns to the soil.
Nitrogen is a bit more complex - some of it cycles from decaying material (similar process to potassium) and some of it is extracted from the nitrogen in the air. Bacteria in the soil convert N2 to ammonium (NH4) which is then converted by other bacteria to nitrites/nitrates, which can be used by plants. Some plants (legumes) have bacteria that live in their root nodules that convert N2 immediately into a usable form for that plant. Needless to say, when those plants die, plenty of nitrogen is recycled into the soil.

Answer 2

P exists in minerals this is incorporated in living organisms

Originaly only natural wearing released it to plants in the water and on land. Now phosphate fertilizers are made by treating rock phosphate (mined phosphate-bearing mineral) with acid to make it more soluble.
Manure contains soluble phosphate, organic phosphate, and inorganic phosphate compounds.
It comes from every cell in a plant or animal that dies. From their bones, DNA, ATP, membranes, etc.
It does not come from the air.

Nitrogen does come from the air as a gas. Then nitrifying bacteria fix it into the soil. This then cycles through the usual process involving bacteria and fungi to make it available to plants. It is the symbiosis between soil biota that cycles the elements of N, P, K, Ca, Mg, & etc. into plants in exchange for carbohydrate exudates made by the plants photosynthesis.

Answer 3

Where Does Soil Come From

Answer 4

In the process of organic matter degrading.

check "composting" websites