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12th ncert : causes of loss of biodiversity with suitable examples
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This course includes biodiversity and conservation in simple language and in an easy way. It mainly concentrates on beginners to get them with their basics. It also aims to generate interest among the viewers on the topic and also learning with fun.

Pillai Sruthi P Kumar
Pursuing MSc (botany, Cytogenetics), Mumbai University. Youtuber#sruthipillai. Work as a Biofaculty @MtEducare (reputed institute) Mumbai

Unacademy user
thanks sir. it was really helpful :)
I think both 1nd 2
Thank you for taking your valuable time to comment Divyanshu... your comments make my day😄 The answer is d... neither 1 and 2 Because Biodiversity hotspots are not limited to tropical areas And the Himalayas, the Western Ghats, the Indo-Burma region and the Sundaland which includes nicobar group of islands are hotspots in India
  1. Pillai Sruthi P Kumar ' BSc. Botany (graduate) Graduate (Visharad) in Hindustani Classical Mu Trained Bharatnatyam Classical Dancer. A passionate speaker. . A civil service aspirant. Please do rate, review and recommend if you genuinely liked my will definitely make a difference in my life... Follow me through unacademy app for future notifications...

  2. Objective .This course will complete the remaining three chapters (12th ncert) part by part included in the portion of topic ENVIRONMENT' important for GS section of UPSC exam. The main objective is to explain the concepts as simply as possible, to clear the basics, especially focuses on beginners, and tries to generate an interest among viewers by being more creative. Source 12th ncert

  3. Target audience UPSC aspirants .SSC .CDS Railway etc.


  5. Some examples of recent extinctions... Dodo(Mauritius) Quagga(Africa) Thylacine(Austral'

  6. Some examples of recent extinctions... Steller's sea cow(Russia) 3 subspecies Bali, aenaspian

  7. Disappearance of 27 species in last twenty years More than 15,500 species world wide facing the threat of extinction

  8. According to ecologists, on the basis of the current rate, all the species on the earth might be wiped out within the next 100 years Sixth extinction - presently in progress Large scale loss of species - pre - human times - >3 billion years ago Is there any difference in the current and previous extinctions??? V There were 5 episodes of mass extinction of species since the origin and diversification of life on earth Species extinction rate: 100 to 1000 times faster currently due to manmade activities

  9. Consequences??? Decline in plant production Lowered resistance to environmental perturbations such as drought Increased variability in certain ecosystem processes such as plant productivity, water use, and pest and disease cycles.

  10. Causes??? There are 4 major major causes... 'EVIL QUARTET Habitat loss and fragmentation V over - exploitation Alien species invasions VCo - extinctions

  11. Tropical rainforests can be characterized in two words: hot and wet. Mean monthly temperatures exceed 18 C (64 F) during all months of the year. Average annual rainfall is no less than 1,680 mm and can exceed 10 m Though it typically lies between 1,750 mm (69 in) and 3,000 mm (120 in) This high level of precipitation often results in poor soils due to leaching of soluble nutrients in the ground. Tropical rainforests exhibit high

  12. Arctic Ocean The largest rainforests are in the Amazon River Basin (South America), the Congo River Basin (western Africa and throughout much of southeast Asi Arctic Ocean GREENLAND ASIA NORTH AMERICA EUROPE North Pacific Ocean North Atlantic Ocean North Pacific Ocean AFRICA Indian Ocean Smaller rainforests are located in Central America, SOUTH AMERIC USTRALIA South Atlantic South Pacific Ocean Madagascar, Australia and nearby islands, India, and other locations in the tropics. Guyana Suriname Venezuela French Guiana Colom Ecuador Brasil Paraguay

  13. Several species of toucans, parrots and other tropical birds of the South and Central American rainforests are threatened with extinction The harpy eagle, one of the largest known eagle species worldwide, thrives in tropical rainforest lowlands from southern Mexico to eastern Bolivia Habitat loss also threatens thousands of migratory bird species. Tennessee warbler Yellow warbler

  14. Over exploitation Need turns to greed Over- exploitation of natural resources by human Hilsa shad OVER - EXPLOITATI ON catla Endangers continued existence if some commercially Over -harvesting of marine fish populations around the world Silver carp important species Grass carp

  15. Alien species invasions Some of thenm may turm invasive Eg introduction of Nile perch in to Lake Victoria in East Africa ALIEN SPECIES INVASIONS Recent example - illegal introduction of of the African catfish Clarias gariepinus Environmental damage causea and threat posted to our native species by invasive weed species

  16. Turisia Lake Victoria Algeria Libya Egypt taniaMal Niger/chad rChad Sudan Nigeria Ethiopia Cote roire Rep Republic of the Congo UGANDA Angola Lake Fietoria KENYA uth TANZANIA