International efforts and a revision of the chapter

One Earth, many nations

A migratory bird crosses many countries in a year. A river carries a pollutant across a border. No one country can save biodiversity alone. So nations have made agreements.

International efforts

This part is not in the NEET syllabus, but A-Level, IB and AP ask it.

• The Earth Summit. In 1992, at Rio de Janeiro, in Brazil, the nations of the world were called upon to take suitable steps. The steps were to conserve biodiversity and to use its benefits in a sustainable way. The Convention on Biological Diversity came out of this meeting.
• The World Summit on Sustainable Development. In 2002, at Johannesburg, in South Africa, 190 countries pledged to achieve by 2010 a significant reduction in the current rate of biodiversity loss. They promised it at the global, the regional and the local levels.

Two other agreements are often named. The Ramsar Convention of 1971 is about wetlands. CITES, of 1973, controls the trade in threatened species. India has its own Biological Diversity Act of 2002. These three are standard knowledge, and they are not part of the NCERT text of this chapter.

The whole chapter in one view

The chapter has a story. Biodiversity has three levels, and it is richest in the tropics. Species and area are linked by $S = C A^{Z}$. Species are being lost faster than ever, mainly because of the evil quartet. We conserve them in two ways, in situ and ex situ.

The traps of this chapter

These are the slips that cost marks.

• Hotspots. Less than 2 per cent of the land. Almost 30 per cent fewer extinctions. Three in India in NCERT.
• Protected areas. 14 biosphere reserves, 90 national parks, 448 sanctuaries. The core zone has no human activity.
• Sacred groves. Meghalaya has the Khasi and Jaintia Hills. They are in situ.
• Ex situ. Zoos, botanical gardens, seed banks and cryopreserved gametes. Not a sanctuary.
• Categories. Extinct in the Wild is not Extinct. Threatened means CR, EN and VU.
• Causes. The evil quartet, and the most important is habitat loss and fragmentation.

Try it in Python

The program sorts the examples of conservation into in situ and ex situ. It is a way to check your own list.

Practise with new numbers

Common mistakes

• Giving the date of the Earth Summit as 2002. It was 1992, at Rio de Janeiro. The 2002 meeting was at Johannesburg.
• Writing that the target of 2010 was to stop the loss. It was to reduce the rate of the loss significantly.
• Mixing up the number of the countries. It was 190 countries at Johannesburg.
• Believing that a sanctuary is ex situ. It protects animals in their own habitat.

Remember these

• Earth Summit, Rio de Janeiro, 1992. World Summit, Johannesburg, 2002, 190 countries, target year 2010.
• Ramsar 1971, CITES 1973 and the Biological Diversity Act 2002 are standard knowledge.
• In situ: hotspots, sacred groves, national parks, sanctuaries, biosphere reserves. Ex situ: zoos, botanical gardens, seed banks, cryopreservation.
• Threatened means Critically Endangered, Endangered or Vulnerable.

Check yourself

Try each one on your own first. If you are stuck, open a hint. Then check with Show the answer.

1. Where and when was the Earth Summit held?

2. What did the 190 countries pledge at Johannesburg?

3. Sort these into in situ and ex situ: sacred grove, seed bank, sanctuary, botanical garden.

4. A model region expects to lose 600 species. By how many species can strict protection of the hotspots reduce the loss?

5. Which threatened category is the highest in risk?

References

• NCERT (2023). Biology, Textbook for Class XII, chapter 13, Biodiversity and Conservation, section on international efforts.
• OpenStax Biology 2e (2018), chapter 47, Conservation Biology and Biodiversity.
• Campbell Biology, 12th edition (2021), Pearson, chapter 56, Conservation Biology and Restoration Ecology.