About $70\%$ of total global carbon is found in

The character of an ecosystem is determined by the environmental factor which is in the shortest supply. This is known as the:

Mass of living matter at a trophic level in an area at any time is called

$A$ farmer harvests his crop and expresses his harvest in three different ways.
$(a)$ $I$ have harvested $10$ quintals of wheat.
$(b)$ $I$ have harvested $10$ quintals of wheat today in one acre of land.
$(c)$ $I$ have harvested $10$ quintals of wheat in one acre of land,$6$ months after sowing.
Do the above statements mean one and the same thing? If your answer is yes,give reasons. If your answer is 'no',explain the meaning of each expression.

In an ecosystem,which of the following is not static?

Plant succession occurring in a sandy area is known as: