Earth is a/an

The pioneer species in a hydrarch succession are:

In a pond,we see plants which are free-floating; rooted-submerged; rooted-emergent; and rooted with floating leaves. Identify the type of plant for each of the following:

Plant Name	Type
$(1)$ Hydrilla	....................
$(2)$ Typha	....................
$(3)$ Nymphaea	....................
$(4)$ Lemna	....................
$(5)$ Vallisneria	....................

Which of the following statements is incorrect?

In a lake,phytoplankton grow abundantly in

When a man eats a fish which feeds on zooplanktons which have eaten small plants,the producer in this chain is: