Phosphorus of the ocean becomes available to land plants due to:

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.

The phosphates remain outside the natural cycle for a long time:

Consider the following statements concerning food chains.
$A.$ Removal of $80\%$ tigers from an area resulted in greatly increased growth of vegetation.
$B.$ Removal of most of the carnivores resulted in an increased population of deers.
$C.$ The length of food chains is generally limited to $3-4$ trophic levels due to energy loss.
$D.$ The length of food chains may vary from $2$ to $8$ trophic levels.
Which two of the above statements are correct?

Match the following:

Trophic levels	Examples
$A$. First	$a$. Man
$B$. Second	$b$. Wolf
$C$. Third	$c$. Cow
$D$. Fourth	$d$. Phytoplankton

Which of the following is $NOT$ a gaseous biogeochemical cycle in an ecosystem?