Which cycle is represented by the given figure?

Which of the following statements regarding food chains are considered correct?
$(1)$ Removal of $80\%$ of tigers from an area results in greatly increased growth of vegetation.
$(2)$ Removal of most carnivores results in an increased population of deer.
$(3)$ The length of food chains is generally limited to $3-4$ trophic levels due to energy loss.
$(4)$ The length of food chains can vary from $2$ to $8$ trophic levels.

Water plants provide ....... to water animals.

According to $David \ Tilman$,greater the diversity,greater is the primary productivity. Can you think of a very low diversity man-made ecosystem that has high productivity?

In an aquatic ecosystem,maximum biomagnification is seen among the

Match the following columns.

Column-$I$	Column-$II$
$(a)$ Phytoplankton,grass	$(p)$ First trophic level
$(b)$ Man,Lion	$(q)$ Herbivore
$(c)$ Zooplankton,Cow,Grasshopper	$(r)$ Third trophic level
$(d)$ Birds,Wolf	$(s)$ Top carnivore