What is formed by the interaction between biotic communities and their environment?

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

Classify the following ecosystems into their appropriate groups:
$I-$ Forest,$II-$ Grassland,$III-$ Pond,$IV-$ Desert
$V-$ Lake,$VI-$ Wetland,$VII-$ River,$VIII-$ Estuary
Terrestrial Ecosystem $\quad$ Aquatic Ecosystem

$A$ sedimentary cycle that also has a small gaseous component is found in

Which quantity of energy drives the living world on Earth?

Climax vegetation of a region is generally