3. Importance of Biodiversity

Question 1

Reasons for maintaining biodiversity

Answer 1

• Ecological reasons
• Economic reasons
• Aesthetic reasons

Question 2

ECOLOGICAL reasons for maintaining biodiversity

Answer 2

1. To protect species, including keystone species
2. To maintain genetic resources

Question 3

What is an ecosystem

Answer 3

All the biotic factors (living organisms) living in a particular area & all the abiotic factors (non-living conditions).
INTERDEPNDENT

Question 4

ECOLOGICAL reasons: 1. To protect species, including keystone species PART 1

Answer 4

• Organisms in an ecosystem are interdependent - they depend on eachother to survive, loss of one species can have drastic effects on an ecosystem such as:
  
  1. Disruption of food chains - eg. species of bear feed on salmon, which feed on herring. If no. of herring decline, can affect both salmon & bear pops.
  2. Disruption of nutrient cycles - eg. decomposers like worms improve quality of soil by recycling nutrients. If worm no.s decline, soil quality is affected. Will affect growth of plants & amount of food available to animals.

Question 5

ECOLOGICAL reasons: 1. To protect species, including keystone species PART 2

Answer 5

• There are some species on which many other species in ecosystem depend on & w/o which the ecosystem would change dramatically - KEYSTONE SPECIES.
• Keystone species are often predators - keeping pop of prey in check, but can also be modifiers - maintaining the env needed for the ecosystem, or hosts - plants that provide a particular env (sa palm trees).

Question 6

Eg of keystone species needed?

Question 7

ECOLOGICAL reasons: 2. To maintain genetic resources

Answer 7

• Genetic resources refer to any material from plants, animals or microorganisms, containing genes, that we find valuable.
• Could be crops, plants used for medicines, microorganisms used in industrial processes, or animal breeds. We need to maintain genetic resources for following reasons:
  
  1. Food & drinks - from plants/animals
  2. Clothing - fibres & fabrics from plants/animals
  3. Drugs - from plant comports (eg morphine from poppies)
  4. Fuels - renewable fuel (eg. ethanol) sources
  5. Other industrial materials - many other materials produced from plant/animal (eg, wood, paper, dyes, oils, pesticides)

Question 8

How does ecological reason link to economic

Answer 8

Many genetic resources (2.) are importance for global economy - products derived from plant/animal species traded on local & global scale.

Question 9

How can genetic resources allow us to adapt to changes in environment

Answer 9

• For eg, climate change may mean some crops wont be anle grow in same areas as they do now (eg. droughts).
• HOWEVER, we may be able to use genes from a plant that resistant to droughts to genetically engineer a drought-resistant crop.

Question 10

ECONOMIC reasons for maintaining biodiversity

Answer 10

1. To reduce soil depletion

Question 11

ECONOMIC reasons: 1. To reduce soil depletion

Answer 11

• Continuous monoculture involves planting the same crops in the same field w/o interruption.
• Causes soil depletion bc nutrients required by crop are gradually used up. (In more traditional farming, crops are rotated w other types of crops, so nutrients & organic matter are replaced).
• The economic costs of soil depletion increased spending on fertilisers & decreased yields (crops produced).

Question 12

AESTHETIC reasons for maintaining biodiversity

Answer 12

• Some ppl believe we should conserve biodiversity as it brings joy to millions.
• Areas rich in biodiversity provide pleasant, attractive landscapes ppl can enjoy - by maintaining it, we protect these landscapes.
• The more biodiversity in an area, the more visitors it attracts - economic advantages.