Which trophic level organisms do secondary carnivores use as food?

Identify the pioneer species that colonize bare rock.

Which of the following has the largest biomass of autotrophs in the world's oceans?

An ecosystem resists change because it is in a state of

The ecosystem consists of

Distinguish between primary succession and secondary succession based on the following examples:
$I-$ Abandoned farmland
$II-$ Burned or cut forests
$III-$ Newly cooled lava
$IV -$ Bare rock
$V -$ Flooded lands
$VI -$ Newly created pond or reservoir
Identify the correct grouping for primary succession and secondary succession respectively.