Ecosystem Benefits and the Sundarbans (12.9) — "How Nature Works in Harmony"

1. 13 marks

   List the benefits forests and aquatic ecosystems provide to humans, according to the chapter.

   Hint. The chapter names several concrete resources for each ecosystem type, plus a non-material kind of benefit.

   ✦ Forests provide fresh air, fertile soil, food, fibres, timber, and medicines. Aquatic ecosystems provide water and food. Beyond these material resources, ecosystems also offer aesthetic and recreational value — 'since these support our well-being and show how closely nature and humans are connected.'

2. 24 marks

   Describe the Sundarbans: its location, its ecological importance, and how it protects nearby human communities.

   Hint. It sits at a specific river confluence, holds a specific world record, and provides a specific kind of physical protection.

   ✦ The Sundarbans has the largest mangrove forests in the world, located where the Ganges and Brahmaputra Rivers meet, between India and Bangladesh — home to various flora and fauna, many of which are endangered. It protects nearby communities by slowing down strong winds and waves during storms and floods, and its trees also absorb carbon dioxide from the air and release oxygen. Because of its importance, UNESCO declared the Sundarbans a World Heritage Site in 1987.

3. 33 marks

   List the specific threats facing the Sundarbans, according to the chapter.

   Hint. Three distinct categories of threat: one about the trees themselves, one about wildlife, one about water.

   ✦ Mangrove trees are being cut for fuelwood and farming; illegal hunting and overuse of forest resources threaten the wildlife living there; and pollution from industrial waste and untreated sewage in rivers is damaging the water and habitat — since all of these are human activities disrupting the natural way the ecosystem works.

4. 43 marks

   What are protected areas, and name three examples given in the chapter along with their locations.

   Hint. The chapter lists eight named protected areas across India — pick any three with their states.

   ✦ Protected areas are parts of land or water set aside to conserve wildlife and their habitats, including national parks, wildlife sanctuaries, biosphere reserves, and community conserved areas. Any three of the chapter's examples: Jim Corbett National Park (Uttarakhand), Manas National Park (Assam), Nilgiri Biosphere Reserve (Western Ghats), Chilika Lake (Odisha), Eaglenest Wildlife Sanctuary (Arunachal Pradesh), Hemis National Park (Leh), Keibul Lamjao National Park (Manipur), or Pirotan Island Marine National Park (Gujarat) — since these are the examples the chapter names directly.

5. 53 marks

   Beyond the Sundarbans, what broader problems does the chapter say are threatening ecosystems across India?

   Hint. Five named problems, affecting a range of different ecosystem types.

   ✦ Deforestation, overuse of natural resources, the spread of invasive species, unsustainable land use, and pollution are damaging forests, rivers, scrublands, wetlands, grasslands, and coastal areas across India — since these are the same broad categories of harm illustrated in detail by the Sundarbans case study.

Solutions written by the tuition.in editorial team and checked against NCERT Curiosity — Textbook of Science for Grade 8, Chapter 12 (hecu112.pdf), Reprint 2026-27, pages 190-209. Questions are referenced from the NCERT textbook for identification.