Biodiversity And Conservation

Biodiversity and Conservation: A Summary

Biodiversity refers to the variety of life on Earth, including all plants, animals, microorganisms, and their ecosystems. It is essential for the health and functioning of our planet.

Levels of Biodiversity

• Genetic Diversity: Variation within a species.
• Species Diversity: The variety of species in a given area.
• Ecosystem Diversity

Importance of Biodiversity

• Ecological Stability: Biodiversity helps maintain the balance and stability of ecosystems.
• Genetic Resources: It provides a pool of genetic material for developing new crops and medicines.
• Ecosystem Services: Biodiversity supports essential ecosystem functions like pollination, nutrient cycling, and climate regulation.
• Cultural and Economic Benefits: Biodiversity contributes to human well-being and economic activities, such as tourism and agriculture.

Threats to Biodiversity

• Habitat Loss
• Overexploitation: Excessive use of natural resources, leading to the depletion of species.
• Pollution: Contamination of air, water, and soil with pollutants that harm biodiversity.
• Climate Change: Altering global temperatures and weather patterns, affecting species distributions and habitats.
• Introduced Species: Invasive species that outcompete native species.

Exercise

1. Name the three important components of biodiversity. 

Ans : The three important components of biodiversity are:

1. Genetic diversity: This refers to the variation in genetic material within a species. It allows species to adapt to changing environmental conditions.
2. Species diversity: This refers to the variety of species in a given area. It is a measure of the richness and complexity of an ecosystem.
3. Ecosystem diversity: This refers to the variety of ecosystems in a region. It includes different habitats, communities, and ecological processes.

2. How do ecologists estimate the total number of species present in the world?

Ans : 

Ecologists estimate the total number of species present in the world using a variety of methods:

1. Species Richness Surveys: Researchers conduct surveys in different habitats to count the number of species present. This involves collecting and identifying specimens, often with the help of experts in various taxonomic groups.  
3. Extrapolation from Known Groups: By studying well-known groups of organisms (e.g., insects, plants), ecologists can estimate the total number of species within that group and then extrapolate this figure to other groups.  
5. Statistical Modeling: Mathematical models can be used to predict the number of species in unexplored or inaccessible habitats based on factors like climate, vegetation, and geographic location.
6. DNA Barcoding: This technique involves sequencing a specific region of DNA (usually the mitochondrial cytochrome c oxidase I gene) to identify species. By comparing DNA barcodes, researchers can estimate species diversity and identify new species.

3. Give three hypotheses for explaining why tropics show greatest levels of species richness. 

Ans : 

Here are three hypotheses for explaining why the tropics show the greatest levels of species richness:

1. High Primary Productivity: The tropics receive abundant sunlight and rainfall, leading to high primary productivity (the rate at which organic matter is produced by plants). This abundance of food and energy supports a diverse range of species.
2. Stable Climate: Tropical regions generally have more stable climates compared to temperate and polar regions. This stability allows for the evolution and coexistence of a greater variety of species.
3. Old Age: Tropical ecosystems are generally older than temperate or polar ecosystems, having existed for millions of years. This long evolutionary history has allowed for the development of a diverse array of species and ecological niches.

4. What is the significance of the slope of regression in a species – area relationship?

Ans : 

The slope of the regression line in a species-area relationship represents the rate at which species richness increases with increasing area.

In other words, it indicates how many additional species are expected to be found in a given increase in area. A steeper slope suggests that a larger number of new species are found per unit area increase, while a shallower slope indicates a slower rate of species accumulation.

Key points about the slope of the species-area relationship:

• Higher slope: A higher slope typically indicates a higher species diversity in the region.
• Island biogeography: This relationship is particularly well-studied in island biogeography, where the number of species on an island is often found to increase with the size of the island.
• Conservation biology: Understanding the species-area relationship is important for conservation efforts, as it helps to predict the impact of habitat loss on biodiversity.

5. What are the major causes of species losses in a geographical region?

Ans : 

Major causes of species losses in a geographical region include:

1. Habitat Loss and Degradation:
   • Deforestation
   • Urbanization
   • Conversion of natural areas for agriculture or development
2. Overexploitation:
   • Overfishing
   • Overhunting
   • Unsustainable harvesting of natural resources
3. Pollution:
   • Air pollution
   • Water pollution
   • Soil pollution
4. Climate Change:
   • Rising temperatures
   • Changes in precipitation patterns
   • Ocean acidification
5. Introduced Species:
   • Invasive species that outcompete native species

6. How is biodiversity important for ecosystem functioning?

Ans : 

Biodiversity plays a crucial role in ecosystem functioning. It ensures the stability and resilience of ecosystems, as well as the provision of essential services. Here are some key ways in which biodiversity is important:

1. Ecosystem Stability:Different species play complementary roles in the ecosystem, ensuring that it can continue to function even if some species are lost.
2. Nutrient Cycling: Biodiversity is essential for nutrient cycling, which is the process by which nutrients are recycled through the ecosystem. Different species contribute to the decomposition of organic matter and the release of nutrients into the soil, making them available for plants to use.
3. Pollination: Biodiversity ensures that there are sufficient pollinators to maintain plant diversity and ecosystem health.
4. Pest Control: Biodiversity can help control pests and diseases. Natural predators and parasites can help regulate populations of harmful insects and pathogens.
5. Climate Regulation: Forests and other ecosystems play a crucial role in regulating the Earth’s climate by absorbing carbon dioxide and releasing oxygen. Biodiversity is essential for maintaining the health and functioning of these ecosystems.
6. Genetic Diversity: Biodiversity provides a genetic reservoir that allows species to adapt to changing environmental conditions. 

7. What are sacred groves? What is their role in conservation? 

Ans :

acred groves are patches of forest or woodland that are protected by local communities due to religious or cultural beliefs. These areas are often considered sacred or holy, and their preservation is often linked to traditional customs and practices.

Sacred groves play a crucial role in conservation:

• Biodiversity hotspots: They often harbor a high diversity of plant and animal species, making them important biodiversity hotspots.
• Ecosystem services: Sacred groves provide various ecosystem services, such as erosion control, water purification, and climate regulation.
• Cultural heritage: They are often associated with local traditions, folklore, and religious beliefs, preserving cultural heritage.
• Community involvement: Sacred groves are often protected by local communities, fostering a sense of ownership and responsibility for their conservation.
• Refuges for endangered species: Many sacred groves provide safe havens for endangered and threatened species.

8. Among the ecosystem services are control of floods and soil erosion. How is this achieved by the biotic components of the ecosystem? 

Ans : 

Ecosystems provide valuable services like flood control and soil erosion prevention through the actions of their biotic components.

Here’s how:

1. Plant Roots:
   
   • Soil Anchoring: Plant roots bind soil particles together, preventing erosion and stabilizing slopes.
   • Water Absorption: Roots absorb excess water from the soil, reducing the risk of flooding.
2. Vegetation Cover:
   
   • Erosion Prevention: Dense vegetation cover acts as a natural barrier against wind and rain, reducing soil erosion.
   • Water Retention: Plants help retain moisture in the soil, reducing runoff and the risk of flooding.
3. Forest Canopies:
   
   • Rainfall Interception: Tree canopies intercept rainfall, allowing for gradual infiltration of water into the soil.
   • Sediment Trapping: Leaves and branches help trap sediments, reducing the amount of sediment that reaches waterways.
4. Wetlands:
   
   • Water Storage: Wetlands act as natural sponges, absorbing excess water and releasing it slowly.
   • Sediment Filtration: Wetlands filter pollutants and sediments from water, improving water quality.

9. The species diversity of plants (22 per cent) is much less than that of animals (72 per cent). What could be the explanations to how animals achieved greater diversification?

Ans : 

The higher species diversity of animals compared to plants can be attributed to several factors:

1. Evolutionary History: Animals have a longer evolutionary history than plants, which has allowed for greater diversification and speciation.
2. Complex Body Plans: Animals have more complex body plans and behaviors than plants, which can lead to a wider range of ecological niches and adaptations.
3. Sexual Reproduction: Animals generally have more complex sexual reproduction systems than plants, which can promote genetic diversity and speciation.
4. Rapid Evolution: Animals can often evolve more rapidly than plants, allowing them to adapt to changing environmental conditions and colonize new habitats.
5. Smaller Size: Many animal species are smaller than plants, allowing them to occupy a wider range of habitats and niches.
6. Greater Mobility: Animals are generally more mobile than plants, which allows them to disperse to new areas and colonize new habitats.

10. Can you think of a situation where we deliberately want to make a species extinct? How would you justify it?

Ans : 

Yes, there are rare instances where the deliberate extinction of a species might be considered. However, it’s important to emphasize that this should be a last resort and only undertaken with extreme caution and careful consideration.

Here’s a hypothetical situation:

• Disease-Carrying Species: If a species is the primary vector for a deadly and incurable disease that poses a significant threat to human health or the survival of other species, its extinction might be considered as a last resort to prevent further harm. For example, if a particular mosquito species were the sole carrier of a highly contagious and lethal virus, and no other effective control measures were available, the eradication of that species might be explored.

Justifications:

• Human Health: Preserving human health and well-being is a paramount concern.
• Species Conservation: In some cases, eradicating one species might be necessary to protect other species that are at risk of extinction due to predation or competition.
• Ecosystem Balance: While extinction is generally harmful to biodiversity, in rare cases, it might be necessary to restore a disrupted ecosystem balance.