Loss of Biodiversity: Types, Definition and Causes

Ans: Biodiversity plays an important role in many ecosystem services that nature provides. The two ecosystem services are:

(i) Forest ecosystem reduced the causes of droughts and floods.

(ii) The wildlife helps in pollination of crops.

Answer: (i) It is an example of ex-situ conservation. In this the threatened plants and animals are taken off from their existing place and are placed in a suitable environment. Special care is given to these types of animals and plants.

(ii) Cryopreservation and tissue culture are two ways that help in ex-situ conservation. In cryopreservation, gametes of threatened species are preserved in viable and fertile conditions at subzero temperatures. It further helps in preserving the cells of the organism for longer periods. In tissue culture, plants are propagated from a small mass of tissue called callus.

Ans: (i) Biodiversity provides a number of direct and indirect services to human beings. The biodiversity is needed to be conserved because of the following reasons- 

• The diversity of plants and animals produces a vast variety of food and fabrics.
• It helps in maintaining the ecological balance for ecosystem stability.
• Preserving biodiversity provides an economic benefit too. It improves the characteristics of crop making plants more pest resistant, providing medicine to treat and cure illness.
• Biodiversity integers the life of people and industrialized old and developed countries and provide the means of survival for people and developing countries. 

(i) There are various reasons for the loss of biodiversity- 

• Pollution- Pollution is adversely affecting the environment. It alters the flow of energy and abundance of species.
• Climate change- Due to climate change, many species are becoming endangered.
• Overexploitation of resources- Human beings are using natural resources to a great extent. The trees are cutting down severely and the animals are being slaughtered to satisfy the human needs.
• Population explosion- The population is increasing rapidly and the land for the people is not that enough. Due to which trees are being cut down to build houses which eventually led to the decrement in the land for the animals to live.

Ans: Major causes for the loss of biodiversity are-

• Loss of Habitat and Fragmentation- Large-scale deforestation is common from hundreds of years. It is done to make way for human activities. Eventually, it leads to habitat loss. It also leads to the fragmentation of the habitats into smaller parts. This form of reduction is the major cause of the loss of biodiversity in the present age. The most factual example of this type of loss of biodiversity is the tropical rainforest. These rain forests used to cover around 14% of the land surface of the Earth. Now, it just covers 6%. Loss of habitats is also possible by the high levels of pollution presently.
• Over Exploitation of Natural Resources- The human need has turned into human greed. To fulfill this greed, there has been over-exploitation of the natural resources present on the planet. A large number of exploitation of plants and animal species have led to the loss of biodiversity.
• Alien Species Invasion- When alien species turn invasive, they result in the loss and extinction of indigenous species. For example - the introduction of hyacinth has caused damage to the indigenous species. The introduction of the African catfish Clarias gariepinus for the purpose of aquaculture poses a threat to the indigenous catfishes in those rivers.
• Co-Extinction- Some species are associated with another. If one of them gets extinct, the other follows. This can be explained in this manner. For example, if a type of host fish becomes extinct, the parasites that are dependent on it become extinct too.

Ans: Biodiversity provides various direct or indirect services to human beings. These are-

i) Source of food & improved varieties

ii) Fats & Oils

iii) Fibres

iv) Resins

v) Gums, Timber, Paper, Tannins, Dyes

vi) Drugs & Medicines

vii) Stability of Ecosystem

viii) Aesthetic, Scientific & Recreational values

Ans: Preservation of material in liquid nitrogen at – 196°C is called cryopreservation. It is useful in conserving biodiversity as via this method, threatened species can be preserved in a fertile and viable environment for a long period of time. 

Ans: The loss of biodiversity in a region can lead to

• Reduction in plant production. 
• Conditions like drought.
• Increased variability in certain ecosystems processes

Ans: The areas of importance and priority where conservation is necessary to prevent the extinction of species are called hot spots in terms of loss of biodiversity.

Ans: Endemic species are native species that are restricted to a particular geographical area whereas, exotic species are derived into a geographical area from another geographical area. 

Ans: Rivet Popper Hypothesis was conceived by Paul Ehrlich. He is a Standard based ecologist. He used the following analogy to explain the possible consequences of the reduction of species - he compared the Earth’s ecosystem with an airplane and the species present in the earth with rivets. Thousands of rivets are used in an airplane to join its various parts. If each passenger removes one rivet to take home as a souvenir, it will not affect the functioning of the airplane and its safety at first but in the long run, it definitely will. Also, he stated the placement of some rivets is important. If rivets from this area are taken away, it will cause more danger to the airplane. For example, taking out the rivets of the wings rather than the seats. In a similar way, extinction of a particular or a few species will not be harmful to the ecosystem but the extinction of an important species can cause great damage and havoc to the ecosystem.