(i) 'Swachh Bharat Abhiyan' is a cleanliness drive launched by Shri Narendra Modi, Prime Minister of India on 2 October 2014. I totally support this campaign.This initiative is needed to solve the sanitation problem and waste management in India. Following this drive by all citizens will ensure hygiene across the country. It will spread awareness among people on the importance of clean surroundings. An unclean environment leads to various diseases, different types of pollution and creates a feeling of disgust in the minds of viewer. As a responsible Indian citizen, we all should join this drive with enthusiasm.
(ii) Two major problems can be:
(a) Lack of adequate sanitation
(b) Separation of biodegradable and non-biodegradable substances so that they can be treated property.
(iii) Two remedial measures to overcome problems are:
(a) Large number of toilets need to be constructed and people should be made aware about the importance of proper sanitation.
(b) Separate bins have to be installed for biodegradable and non-biodegradable substances.

(i) It is defined as an addition of foreign substances (organic, inorganic, biological or radiological) to water, or a change in its physical property that constitutes a health hazard.
(ii) It is caused by addition of domestic waste, sewage, effluents of industries, surface run offs from agricultural fields having pesticides and fertilisers.
(iii) It is so because Yamuna water is highly polluted and its consumption will result in health problems.

(i)   Pollution may be defined as an undesirable change in the physical, chemical or biological aspects of environment which makes it harmful for humans, for other living organisms and for cultural assets.
(ii)  Pollutants are the substances or energies present in the environment in harmful concentrations.
(iii) Air, water, noise, radioactive, thermal and land pollution.
(iv) Uncle was concerned about the well being of the society.

The uses of the Red list categories: The uses of the Red Lists are:
(i) Developing awareness about the importance of threatened biodiversity;
(ii) Identification and documentation of endangered  species;
(iii) Providing a global index of the decline of biodiversity;
(iv) Define conservation priorities at the local level and guiding conservation action. 

Uses of biodiversity.
1. As source of food and improved varieties.
2. As source of drugs and medicines.
3. Aesthetic and cultural benefits.
Examples of aesthetic rewards include ecotourism, bird watching, wildlife, pet keeping, gardening, etc. Throughout human history, people have related biodiversity to the very existence of human race through cultural and religious beliefs.
4. Biodiversity is essential for the maintenance and sustainable utilization of goods and services from ecological system as well as from individual species.

Ecologist Paul Ehrlich gave 'rivet popper hypothesis' to understand the contribution of the species richness. He compared each species with rivet in the body of an airplane.
(i) This hypothesis explain that ecosystem to be an airplane and the species to be the rivets joining all parts together.
(ii) If every passenger traveling in the airplane start taking rivets home(causing a species to become extinct), initially it may not affect flight safety (proper functioning of ecosystem), but over a period of time the plane become weak and dangerous (Species become endangered and then extinct).

Species diversity decrease as we move towards the poles, because 
(i) Temperature decrease and conditions become harsh.
(ii) Both the amount and intensity of solar radiation decrease.
(iii) Less resources available to support species.
Speciation is generally a function of time and environmental stability, so if condition are too harsh, it is difficult for the species to survive and adapt. this results in decrease in biodiversity towards the poles.

(a) The two desirable approaches to conserve biodiversity are:
(i) In situ conservation and
(ii) Ex situ conservation.

(b) It is a case of coevolution.
1. The orchid Ophrys employs 'sexual deceit' to get pollinated by the specific bumble bee.
2. One petal of its flower bears an uncanny resemblance to the female of the bee, in size, colour and markings on it.
3. The male bee perceives it as a female and pseudocopulates with it; during the process the pollen brought by the bee from another or chid flower is dusted on the stigma.
4. If there occurs even a slight change in the colour or patterns of the female bee, the pollination success will be reduced, unless the orchid coevolves to maintain the resemblance of its petal to the female bee.

Species-Area Relationship
1. Alexander Von Humboldt has observed that within a region, species richness increases with increased explored area, but only upto a limit.
2. The relationship between species richness and area for a number of taxa like angiospermic plants, freshwater fishes and birds is found to be a rectangular hyperbola.
3. On a log scale, the relationship becomes linear (straight line) and is described by the equation:
log S = log C + Z log A, where
S = Species Richness
Z = Slope of the line (regression coefficient)
A = Area and C = Y - intercept
4. Ecologists have found that the value of Z-line ranges between 0.1 and 0.2 irrespective of the taxonomic group of the region.
5. But in very large areas, like a continent, the Z value ranges between 0.6 and 1.2 and indicate species richness.