Questions: Biodiversity and Conservation

Q1. Name the three important components of biodiversity.

Answer (English): The three components are genetic diversity, species diversity and ecological diversity. Genetic diversity is variation within a species, such as the different strains of rice in India. Species diversity is variety at the species level, such as the greater amphibian richness of the Western Ghats. Ecological diversity is variety of ecosystems, such as deserts, mangroves and coral reefs in India.

Hinglish: Teen components hain genetic diversity, species diversity aur ecological diversity. Genetic diversity ek species ke andar variation hai, jaise India mein rice ki alag strains. Species diversity species level ki variety hai, jaise Western Ghats mein zyada amphibian species. Ecological diversity ecosystems ki variety hai, jaise India mein deserts, mangroves aur coral reefs.

Q2. How do ecologists arrive at an estimate of total global species numbers?

Answer (English): Most undescribed species live in the tropics, while inventories are more complete in temperate regions. Ecologists therefore measure the richness of one well-studied insect group in temperate and tropical sites, then apply that ratio to other animals and plants, which gives a rough global total. Robert May's conservative estimate based on this approach is about 7 million species.

Hinglish: Kyunki zyadatar undescribed species tropics mein hain aur temperate regions ke inventories zyada complete hain, ecologists ek thoroughly studied insect group ki temperate aur tropical species richness compare karte hain. Us ratio ko doosre animals aur plants par extrapolate karke global species number ka estimate nikalte hain. Robert May ka conservative estimate lagbhag 7 million hai.

Q3. Give three hypotheses for the greater species richness of the tropics.

Answer (English): First, evolutionary time: tropical regions stayed relatively undisturbed for millions of years while temperate regions suffered repeated glaciations, so the tropics had longer for speciation. Second, environmental stability: tropical climates are less seasonal and more predictable, which favours niche specialisation and more species. Third, solar energy: more solar energy in the tropics supports higher productivity, which contributes indirectly to greater diversity.

Hinglish: Pehla, evolutionary time: tropics millions of years tak undisturbed rahe, jabki temperate regions mein baar baar glaciation hui, isliye tropics ko speciation ke liye zyada samay mila. Doosra, environmental stability: tropics mein seasons kam hote hain aur climate predictable hota hai, jo niche specialisation badhata hai. Teesra, solar energy: zyada solar energy se productivity badhti hai, jo indirectly diversity badhati hai.

Q4. What does the slope of the regression line signify in a species-area curve?

Answer (English): In the equation logS = logC + Z logA, the slope Z measures how fast species richness rises with area. Within a region it usually lies between 0.1 and 0.2, whatever the taxonomic group. Across very large areas such as continents the slope is steeper, from 0.6 to 1.2, which means richness increases much faster with area at that scale.

Hinglish: Equation logS = logC + Z logA mein slope Z batata hai ki area ke saath species richness kitni tezi se badhti hai. Ek region ke andar Z aksar 0.1 se 0.2 tak hota hai, kis group ki baat ho isse farak nahi padta. Continents jaise bade areas ke liye slope zyada steep hota hai, 0.6 se 1.2 tak, matlab us scale par area ke saath richness bahut tezi se badhti hai.

Q5. Name the major reasons why species disappear from a region.

Answer (English): The four major causes are called the evil quartet. Habitat loss and fragmentation is the most important, especially in tropical rain forests cleared for farming and grazing. Over-exploitation removes species faster than they can replace themselves. Alien species invasions cause decline or extinction of native species; the Nile perch in Lake Victoria is a well-known case. Co-extinctions occur when species obliged to live with a lost species also disappear.

Hinglish: Chaar bade causes ko evil quartet kehte hain. Habitat loss aur fragmentation sabse bada hai, khaas taur par tropical rainforests mein jo kheti aur cattle ke liye kate jaate hain. Over-exploitation mein species ko uski replacement rate se zyada nikaal liya jaata hai. Alien species invasion se native species kam ya khatam ho jaati hain; Lake Victoria ka Nile perch iska example hai. Co-extinction mein jo species kisi gayi hui species ke saath bandhi hoti hai woh bhi khatam ho jaati hai.

Q6. How is biodiversity important for ecosystem functioning?

Answer (English): Communities with more species tend to be more stable: their productivity varies less from year to year, they resist or recover from disturbances, and they resist invasion by alien species. Tilman's long-term plot experiments showed less year-to-year variation in biomass in species-rich plots and higher productivity with greater diversity. Ehrlich's rivet popper hypothesis makes the same point: losing a few species may go unnoticed at first, but losing key species is like pulling rivets from an aircraft's wings.

Hinglish: Zyada species wali communities zyada stable hoti hain: productivity saal-dar-saal kam badalti hai, woh disturbances ko jhelti ya recover karti hain, aur alien species ka resistance karti hain. Tilman ke long-term plot experiments mein species-rich plots mein biomass ka variation kam tha aur diversity ke saath productivity zyada thi. Rivet popper hypothesis yahi kehta hai: kuch species ka loss shuru mein dikhta nahi, lekin key species ka loss aeroplane ke wings ke rivets nikalne jaisa hai.

Q7. What are sacred groves, and what is their role in conservation?

Answer (English): Sacred groves are tracts of forest set aside by religious and cultural tradition, with all the trees and wildlife within them venerated and given total protection. They are found in the Khasi and Jaintia Hills of Meghalaya, the Aravalli Hills of Rajasthan, the Western Ghats of Karnataka and Maharashtra, and parts of Madhya Pradesh. They protect many rare and threatened plants; Meghalaya's groves shelter many of these species.

Hinglish: Sacred groves woh forest ke hisse hain jinhe dharm aur culture ke hisaab se alag rakha gaya, aur unke andar ke ped aur wildlife ko pooja aur poora protection milta hai. Ye Meghalaya ke Khasi aur Jaintia Hills, Rajasthan ki Aravalli Hills, Karnataka aur Maharashtra ke Western Ghats, aur Madhya Pradesh ke kuch hisson mein milte hain. Ye bahut si rare aur threatened plants ko bachate hain; Meghalaya mein ye aise species ke last refuge hain.

Q8. Flood control and soil erosion control are ecosystem services. Explain how living components of an ecosystem deliver them.

Answer (English): The biotic components, mainly plants, control floods and soil erosion through their root systems and cover. Roots hold the soil in place, so running water cannot carry it away, and the vegetation slows the flow of water down a slope. The litter and organic matter improve the soil's capacity to absorb water, which reduces the volume that runs off and reaches streams quickly. Forests therefore act as a sponge and as a barrier at the same time.

Hinglish: Biotic components, khaas taur par plants, apni roots aur cover se floods aur soil erosion control karte hain. Roots mitti ko pakad ke rakhte hain, isliye behta paani use baha nahi sakta, aur vegetation dhalan par paani ki raftaar kam karti hai. Litter aur organic matter mitti ki paani sokhne ki kapacity badhate hain, jisse runoff kam hota hai. Isliye forest ek saath sponge aur barrier dono ka kaam karta hai.

Q9. Is there any situation in which we might deliberately want a species to go extinct? Justify your answer.

Answer (English): One situation is the deliberate eradication of a pathogen or a disease vector, such as the smallpox virus or a mosquito species that transmits a serious disease. Another is the removal of an invasive species that is driving native species extinct on an island. The justification rests on human health or on protecting a whole community of native species, and it should be weighed against the loss of any ecological role the species might have. In practice, complete extinction is rarely the goal; control is the usual aim.

Hinglish: Ek situation hai kisi pathogen ya disease vector ko jaan-boojhkar khatam karna, jaise smallpox virus ya koi mosquito species jo gambhir bimari failati hai. Doosri situation hai kisi invasive species ko hatana jo kisi island par native species ko khatam kar rahi ho. Justification human health ya poore native community ko bachane par tiki hoti hai, lekin species ke kisi ecological role ke loss ko bhi sochna chahiye. Practically, poora extinction goal kam hota hai; control zyada aam hai.

Q10. Why should we conserve biodiversity? Give the ethical argument.

Answer (English): The ethical argument is that every species has intrinsic value, whether or not it is economically useful to us today. We share the planet with millions of plant, animal and microbe species; we owe them care and we owe future generations an intact biological legacy. This argument stands on its own even when no direct benefit can be shown.

Hinglish: Ethical argument yeh hai ki har species ki apni intrinsic value hai, chahe woh aaj hamare liye economically useful ho ya na ho. Hum is planet ko lakhon plant, animal aur microbe species ke saath share karte hain, aur unki bhalai ka dhyan rakhna aur biological legacy agli generation tak theek halat mein pahunchana hamara moral duty hai. Yeh argument apne aap mein khada rehta hai, chahe koi direct fayda dikhe ya na dikhe.

To check how much of this stuck, take the five-question quiz below. Each answer explains the reasoning, so read the explanation even when you get it right.

Quiz: the five question check for this chapter is set from the same topics. Attempt it after the questions above, then revisit any topic page where you lost a mark.