Distinguish between gaseous and sedimentary cycles.
$I-$ Sulfur cycle
$II -$ Nitrogen cycle
$III -$ Carbon cycle
$IV -$ Phosphorus cycle
Identify the correct grouping for (Gaseous cycle,Sedimentary cycle).

Composition and structure of communities constantly change in response to the changing environmental conditions. These changes lead finally to a community that is in near equilibrium with the environment and that is called a.......

How many of the following ecosystems are artificial ecosystems?
Forest,Estuary,Paddy field,Desert,Aquarium

Match the following columns:

Column-$I$	Column-$II$
$(P)$ First trophic level	$(I)$ Humans,Lion
$(Q)$ Second trophic level	$(II)$ Zooplankton,Grasshopper,Cow
$(R)$ Third trophic level	$(III)$ Phytoplankton,Grass,Trees
$(S)$ Fourth trophic level	$(IV)$ Birds,Fishes,Wolf

How many of the following basic components are found in a pond ecosystem?
Productivity,Decomposition,Energy flow,Nutrient cycling

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.