Observe the diagram and answer the given question.

The amount of nutrients, such as carbon etc., present in the soil at any specific time is referred to as:

Standing state

The correct answer is Option (2)- Standing state

The amount of nutrients, such as carbon, nitrogen, phosphorus, calcium, etc., present in the soil at any given time, is referred to as the standing state. It varies in different kinds of ecosystems and also on a seasonal basis.
What is important is to appreciate that nutrients which are never lost from the ecosystems, rather they are recycled time and again indefinitely. The movement of nutrient elements through the various components of an ecosystem is called nutrient cycling. Another name of nutrient cycling is biogeochemical cycles (bio: living organism, geo: rocks, air, water).

Nutrient cycles are of two types: (a) gaseous and (b) sedimentary.