Chapter 15: Biodiversity and Conservation

Q1. What is biodiversity? Name its three levels.

Solution

Genetic diversity: Variation in genes within a species
Species diversity: Variety of species in a region
Ecosystem diversity: Variety of ecosystems in a region

Q2. What is the species-area relationship? Who proposed it?

Solution

Proposed by Alexander von Humboldt
Formula: S = cA^z
log S = log c + Z log A
Where: S = species, A = area, c = Y-intercept, Z = regression coefficient
Z: 0.1-0.2 (within continent), 0.6-1.2 (across continents)

Q3. What are biodiversity hotspots? Name some in India.

Solution

Criteria: (1) At least 1500 endemic vascular plants (2) >70% habitat loss
India has 4 hotspots: (1) Western Ghats (2) Eastern Himalayas (3) Indo-Burma (4) Sundaland

Q4. What are the patterns of biodiversity? Explain latitudinal gradient.

Solution

Latitudinal gradient: Species diversity decreases from equator to poles
Reasons: (1) More solar energy (2) More area in tropics (3) Longer evolutionary time (4) Less seasonal variation
Examples: Colombia (1400 birds) vs. Greenland (56)

Q5. What are endangered species? Give examples.

Solution

Examples: (1) Bengal Tiger (2) Indian Rhinoceros (3) Snow Leopard (4) Asian Elephant (5) Great Indian Bustard (6) Nilgiri Tahr

Q6. What is the difference between in-situ and ex-situ conservation?

Solution

In-situ: In natural habitat (National parks, Wildlife sanctuaries, Sacred groves, Biosphere reserves)
Ex-situ: Outside natural habitat (Zoos, Botanical gardens, Seed banks, Cryopreservation)

Q7. What is the Red Data Book?

Solution

Maintained by IUCN
Information: (1) Status of endangered species (2) Population data (3) Threats (4) Conservation measures
Categories: Extinct, Endangered, Vulnerable, Rare

Q8. What are the causes of biodiversity loss?

Solution

1. Habitat loss and fragmentation
2. Over-exploitation
3. Alien species invasions
4. Co-extinction
5. Pollution
6. Climate change

Q9. What are the findings of the IPBES report?

Solution

(1) ~1 million species face extinction (2) 75% of land altered by humans (3) 66% of ocean impacted (4) 500,000+ species face habitat loss

Q10. What is the importance of biodiversity for human welfare?

Solution

1. Food - all food from biodiversity
2. Medicines - drugs from plants and microbes
3. Industrial products - timber, fibers
4. Ecological services - pollination
5. Cultural values - recreation
6. Genetic resources for crop improvement

Q11. What are sacred groves?

Solution

Examples: (1) Sarpa Kavu in Kerala (2) Devara Kadu in Karnataka (3) Sarna in Jharkhand (4) Kavu in Tamil Nadu
Importance: Protect biodiversity, preserve traditional knowledge

Q12. What are the ex-situ conservation methods?

Solution

1. Zoological parks
2. Botanical gardens
3. Seed banks
4. Cryopreservation (liquid nitrogen)
5. Tissue culture
6. DNA banks

Q13. What is the Man and Biosphere Programme (MAB)?

Solution

UNESCO programme (1971) for biodiversity conservation
Biosphere reserves: (1) Core zone - no human activity (2) Buffer zone - limited activity (3) Transition zone - sustainable development
India has 18 biosphere reserves

Q14. What are the methods of in-situ conservation?

Solution

1. National parks (strict protection)
2. Wildlife sanctuaries (limited activity)
3. Biosphere reserves
4. Sacred groves
5. Gene banks in natural habitat
6. Community reserves

Q15. What are the Indian laws for biodiversity conservation?

Solution

1. Wildlife Protection Act, 1972 (amended 2006)
2. Forest Conservation Act, 1980
3. Biological Diversity Act, 2002 (NBA established)
4. Environment Protection Act, 1986
5. National Biodiversity Authority - Chennai
6. Biodiversity Management Committees at local level

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