Chapter 15: Biodiversity and Conservation

Ans: 1. When alien species are introduced into a habitat, whether purposefully or unintentionally, some of them cause the decrease or extinction of indigenous species. Alien species are those that live outside of their normal range and have the ability to disperse. Human activity, whether consciously or unknowingly, spreads alien species. These are dangerous to the local wildlife.

2. The introduction of the Nile perch into the Victoria Lake in east Africa resulted in the demise of an ecologically unique assemblage of over 200 species of cichlid fish in the lake. Carrot grass, lantana, and water hyacinth (Eichornia) are all alien species that pose a serious danger to native species. The unlawful import of the African catfish Clarkias gariepinus for aquaculture reasons has put the indigenous Catfishes in our rivers in jeopardy.

Ans: A healthy environment filters our water, cleans the air, and improves our health. We must maintain the ecosystem's biodiversity in order to keep it alive. It is correct to say that biodiversity is a key indicator of an ecosystem's health. When compared to a high number of variants of a single species, a diverse range of types can withstand harsh environments. Yes, despite the fact that five mass extinctions have already occurred, humanity can still save biodiversity by following these steps.

1. The conservation of useful animals and plants in their natural habitats

2. Protection of key habitats for endangered species, such as feeding, breeding, and resting sites.

3. Hunting should be prohibited or strictly restricted.

4. Farms in the area should be supported.

5. help the bees

6. Plant flowers, fruits, and vegetables native to the area.

7. Reuse and recycle

8. reduce pollution as well as the use of plastic bags

Ans: 1.The Rivet Popper hypothesis was proposed by Paul Ehrlich. He stated the following: "All parts of an aeroplane (environment) are held together by thousands of rivets (species).

2.If every passenger on board starts popping a rivet to take home (causing a species to go extinct), it may not harm flight safety (correct ecosystem functioning) at first, but as more rivets are removed over time, the plane becomes dangerously fragile. It could also make a difference which rivet is removed."

As a result, if the extinction of any species continues, the entire habitat or ecosystem would suffer.

3.There is a woodland region with a diverse range of plants and animals. A particular type of insect lives in the plants that provide food for the birds in that location.

Ans: The battle between people and animals began with man's evolution. Agriculture began 2.5 million years ago, and humans evolved 2.5 million years ago. Humans have been utilising the land area, i.e. the forest area, for farming or extraction of valuable forest products since that time. Human life expectancy has improved as medical technology has progressed. The challenge now is that, as technology and medical research advance, the population is rapidly increasing. As the world's population grows, so does the demand for food, and as a result, we are increasingly investigating land resources. Forests are dwindling day by day, to the point where animals no longer has a natural habitat. These are some of modern man's actions, and we should investigate them.

Ans: A vast range of economic, environmental, and aesthetic products and services are dependent on healthy ecosystems. Ecosystem services are the end result of ecosystem processes. The following are some of the most essential ecosystem services that we receive:

1.Ecosystems purify the air and water, as well as reducing the effects of drought and flooding.

2. Create fertile soil by cycling nutrients.

3.Provide wildlife habitat and maintain biodiversity

4.Pollinate crops and provide a carbon storage site

5.Aesthetic, cultural, and spiritual values are provided.

Ecosystem services have an incalculable value. We're not even able to put a price on it. The average annual cost of these services is US $33 trillion (double the world GNP of $18 trillion), which is taken for granted because they are provided for free.

Ans: Biodiversity refers to the variety of animals and plants found in various habitats. A country's economic growth is also defined by its rich diversity. It makes a significant contribution to the world's food supply.

1.Food is derived from a variety of organisms. As a result, biodiversity has a significant impact on the local way of life.

2.Biodiversity is advantageous in modern agriculture since it indicates a large variety of plant species.

3. About 55 percent of proteins and 60 percent of calories come from only three cereal crops: wheat, rice, and maize.

4. Plants provide the basis for pharmaceuticals such as morphine (papaver somniferum), quinine (chinchona ledgeriana), reserpine (Rawolifa vomitoria), and belladonna (Atropa belladonna). As a result, biodiversity plays a role in medical treatments as well.

5. Medicines such as penicillin and tetracycline are made from many plants and animals.

6. Chorchorus Gossypium is a fibre supply, but jatropha is a biofuel source.

7. Petroleum is made from the remains of living organisms.

We can clearly see the value of biodiversity in a given area based on the examples above. As a result, we must be conscious of the need to conserve the environment.

Ans: As we move away from the equator and toward the poles, species diversity declines. There are a few possibilities:

1.As we move away from the equator and toward the poles, the temperature drops.

2. As we move further from the equator and toward the poles, sunshine and production diminish.

3. Because the temperature in the polar region is so low, most species struggle to survive.

4. Resources are scarcer as you get closer to the pole.

5. There is less greenery.

Speciation is usually determined by the passage of time and the stability of the environment. As a result, the organism cannot survive in hostile environments since it lacks the ability to adapt to the changing surroundings. As a result, biodiversity decreases as you get closer to the pole.

As we move away from the equator and toward the poles, species diversity declines. There are a few possibilities:

1.As we move away from the equator and toward the poles, the temperature drops.

2. As we move further from the equator and toward the poles, sunshine and production diminish.

3. Because the temperature in the polar region is so low, most species struggle to survive.

4. Resources are scarcer as you get closer to the pole.

5. There is less greenery.

Speciation is usually determined by the passage of time and the stability of the environment. As a result, the organism cannot survive in hostile environments since it lacks the ability to adapt to the changing surroundings. As a result, biodiversity decreases as you get closer to the pole.

Ans: 1. The Rivet Popper hypothesis was proposed by Paul Ehrlich. He stated the following: "All parts of an aeroplane (environment) are held together by thousands of rivets (species).

2. If every passenger on board starts popping a rivet to take home (causing a species to go extinct), it may not harm flight safety (correct ecosystem functioning) at first, but as more rivets are removed over time, the plane becomes dangerously fragile. It could also make a difference which rivet is removed."

As a result, if the extinction of any species continues, the entire habitat or ecosystem would suffer.

Ans: Within a region, species richness grew with increasing explored area, but only up to a certain point, according to Alexander von Humboldt.

$\log \mathrm{S}=\log \mathrm{C}+\mathrm{Z} \log \mathrm{A}$

Where

$\mathrm{S}=$ species richness

$\mathrm{C}=\mathrm{y}$ - intercept

$Z=$ slope of the line (regression coefficient)

$\mathrm{A}=$ area

As a result, over a wide range of taxa (birds, bats, angiosperm, gymnosperm, and so on), the relationship between species richness and area appears to be a rectangular hyperbola.

The diversity of species in any given location is determined by a variety of factors.

1.Attaining a healthy balance between immigration and extinction

2.Disturbance rate and magnitude in a small and large area

3. The hunter and the hunted

4.Due to dispersion constraints, members of the same species cluster together.

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