Biodiversity
Biodiversity
Section titled “Biodiversity”2020-04-29 11:11:45
A single species showing genetic variation over its distributional range is called Genetic diversity.
Biodiversity is considered to exist at three levels : genetics, species, and ecosystems.
- Species richness : is the measure of number of species found in a community.
- Alpha diversity : refers to the diversity ==within a particular area== or ecosystem, and is usually expressed by species richness in that ecosystem.
- Beta diversity : comparison of diversity between ecosystems usually ==measured as change in amt of species b/w ecosys==.
- Gamma diversity : is a measure of the ==overall diversity== for the different ecosystems within a region.
- Species evenness measures the proportion of species at a given site.
- Diveristy when an area such as India has more diverse ecosystem like deserts, rain forests, mangroves etc than some scandinavian countries is called Ecological Diversity.
- Species diversity ex Western ghat having greater amphibians species.
Q. What does loss of biodiversity in a region lead to?
- Decline in plant production
- Lowered resistance to env disasters eg droughts etc
- Increased variability in ecosys processes like plant productivity.
Q. What are the causes of biodiversity losses?
- Habitat loss and fragmentation
- Over exploitation
- Alien species invasion
- Co-extinctions
Q. What are certain places where sacred groves could be found?
- Khasi, Jaintia Hills of Meghalaya
- Aravalli Hills of Rajasthan
- Western Ghats of Ktaka and Maha
- Sarguja, Chanda and Bastar areas of Chattisgarh
Q. What are some examples of Ex-situ conservations?
- Zoological parks
- Botanical gardens
- Wildlife safari parks
- In vitro fertilization
In order to control environmental pollution, the Government of India has passed the Environment (Protection) Act, 1986 to protect and improve the quality of our environment.
According to CPCB particulate size ofPM 2.5mmor less are responsible for causing greatest harm to human health.
Eutrophication is the natural aging of a lake by nutrient enrichment of its water.
Pollutants from man’s activities like effluents from the industries and homes can radically accelerate the aging process. This is called Cultural or Accelarated Eutrophication.
The thickness of the ozone in a column of air from the ground to the top of the atmosphere is measured in terms of Dobson units (DU).
Q. What are the various types of UV radiation?
- UV-A : accounts for 95% of UV radiation causes ==tanning effect, sking aging and wrinkling==, recent studies show it may cause skin cancer.
- UV-B : ==Damages DNA and mutation may occur==, causes aging of skin, skin cancers, snow blindness, cataract etc.
- UV-C : Almost ==completely absorbed== by Earth.
Montreal Protocol was signed in 1987 to control emission of ozone depleting substances.
When humus is further degraded by microbes and release of inorganic nutrients occur this process known as mineralisation. This process is faster when detritus is rich in Nitrogen and water soluble substances and slower when it is rich in lignin and chitin.
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[[kegy216.pdf]] - Biodiversity and Conservation