Sequentially arrange the different units of ecological hierarchy.

Pyronema confluens is the indicator of fire - comment.

Given below are few types of plants. Mention their habitats.
(a) Halophytes
(b) Chasmophytes
(c) Cryophytes
(d) Psammophytes.

Specify the type of interactions between the given pair of species.
(a) Spanish moss and Oak tree
(b) Cuscuta and Acacia
(c) Nepenthes and Ants
(d) Alga and fungus

Write a brief note on pneumatophores. Give an example.