These 86 pages exhaustively covers the environment in 86 pages.
Sources used-
1)Books-SHANKAR IAS+for some parts PMF IAS+Environment by Ravi Agrahari
2)Lectures-37 lectures by Sudarshan gurjar+some of Ravi Agrahari sir’s
3)Additionals-You tube Netflix series 7 episodes- OUR PLANET (some ex-2023 prelims-Orangutan ant eating question,ants as a cultivators of fungi etc. Can be solved from these series)