The trophic level of mushroom and Monotropa is

Which of the following ecosystems does not rely on the Sun as its primary source of energy?

The resource which regulates the flow of energy in a desert ecosystem is the availability of

Which structure is composed of two main components: non-living and living?

What does the upper layer of a marine aquatic ecosystem contain?

$A$: Stratification helps in the accommodation of a large number and types of plants in the same area.
$R$: It is the occurrence of horizontal zonation in the ecosystem.