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25 Feb 2023
GS Paper 3
Bio-diversity & Environment
Day 94
Question 1: Discuss the ecosystem and its functions like energy flow, nutrient cycle and ecological succession with adequate examples. (250 words).
Question 2: Like rainforests role as the lungs of the Earth, the mangroves function as its kidneys. Discuss the significance of mangrove. (150 words)Answer 1
Approach
- Write an introduction about the ecosystem.
- Highlight the functions of ecosystems such as energy flow, nutrient cycling and ecological succession with examples.
- Write a holistic and appropriate conclusion.
Introduction
- An ecosystem is a community of living organisms in conjunction with the non-living components of their environment, interacting as a system.
- Ecosystems can be as small as a drop of water or as large as an entire planet, and they vary greatly in their size, complexity, and characteristics.
- Some examples of ecosystems include forests, oceans, deserts, grasslands, and wetlands.
Body
- The functioning of an ecosystem involves the interplay of living and non-living components, and the exchange of energy and matter among them. The key functions of an ecosystem are:
- Energy flow: Energy flows through an ecosystem in a one-way direction, starting from the sun and passing through different trophic levels, from producers to consumers and decomposers. This flow of energy powers all the activities within the ecosystem.
- For example, in the grassland ecosystem, the grass is the primary producer, which means it produces its own food through photosynthesis.
- Grass is then consumed by herbivores, such as rabbits or deer, which are the primary consumers.
- The energy stored in the grass is transferred to the herbivores when they eat the grass.
- Then, the herbivores are consumed by predators, such as coyotes or wolves, which are the secondary consumers.
- Finally, decomposers like bacteria and fungi break down the remains of all the living organisms and return the nutrients back to the soil, which can be used by the primary producers to start the energy flow cycle again.
- Nutrient Cycling: Nutrients, such as carbon, nitrogen, and phosphorus, are cycled between living and nonliving components of an ecosystem. Producers take in nutrients from the environment and use them to build their bodies, which are then consumed by consumers. When organisms die, decomposers break down their bodies and return the nutrients to the soil or water for reuse by other organisms.
- An example of nutrient cycling in an ecosystem can be seen in a forest.
- In a forest ecosystem, fallen leaves and other organic matter on the forest floor provide nutrients for the primary producers, such as trees, shrubs, and ferns.
- The primary producers take in nutrients from the soil, including nitrogen, phosphorus, and potassium, and use them to grow and reproduce.
- As the trees and other primary producers in the forest grow and age, some of them may die or shed leaves, and their organic matter becomes food for decomposers such as fungi, bacteria, and insects.
- These decomposers break down the organic matter into simpler compounds, releasing the nutrients back into the soil.
- This process is called decomposition and it is an important part of the nutrient cycle.
- Biodiversity: Ecosystems support a wide variety of plant and animal species, which contribute to the overall health and resilience of the ecosystem. Biodiversity also provides humans with a range of ecosystem services, such as pollination, pest control, and water purification.
- An example of biodiversity can be seen in a coral reef ecosystem. Coral reefs are some of the most diverse and productive ecosystems on Earth, supporting a wide variety of species, including fish, invertebrates, and plants.
- The corals themselves form the foundation of the reef, providing a complex structure for many other organisms to live and grow on. They also form symbiotic relationships with tiny photosynthetic algae called zooxanthellae, which provide the corals with nutrients and oxygen through photosynthesis.
- Ecological Succession: Ecological succession is the gradual process by which an ecosystem changes over time, as a result of natural disturbances or other environmental changes. An example of ecological succession can be seen in the gradual development of a forest ecosystem.
- Initially, a disturbance such as a wildfire, windstorm, or clearcutting of the land may remove all or most of the existing vegetation in the area.
- This creates an opportunity for new, pioneering species to colonize the area, such as grasses, herbaceous plants, or shrubs that are adapted to living in disturbed or open areas.
- Over time, these pioneering species will begin to modify the environment, by adding organic matter to the soil, increasing soil fertility, and improving soil structure.
- As a result, the area becomes more hospitable to other species, such as small trees or saplings, which begin to grow and eventually form a young forest.
- These intermediate species grow and become the dominant species, as the environmental conditions slowly change to become more favorable for tree growth.
- Energy flow: Energy flows through an ecosystem in a one-way direction, starting from the sun and passing through different trophic levels, from producers to consumers and decomposers. This flow of energy powers all the activities within the ecosystem.
Conclusion
Ecosystems are complex and dynamic systems that support a wide range of life on Earth. It is imperative that we take steps to protect and conserve these ecosystems for future generations, as they provide a wide range of ecosystem services and benefits. By working together to protect the environment, we can ensure that these vital functions continue to support life on Earth and provide a sustainable future for all.
Answer 2
Approach
- Write a brief introduction about rainforest as lungs of earth and kidney as mangroves.
- Write the significance of mangroves function for which it is considered as the kidney of the earth.
- Write an appropriate conclusion.
Introduction
- Rainforests are often referred to as the "lungs of the Earth" due to their ability to produce oxygen through photosynthesis.
- During photosynthesis, plants absorb carbon dioxide and release oxygen, which helps to balance the levels of oxygen and carbon dioxide in the atmosphere.
- Mangroves are complex ecosystems found along coastal areas in tropical and subtropical regions.
- These unique ecosystems are characterized by a mix of salt-tolerant trees, shrubs, and other plants that are adapted to living in a highly dynamic environment.
- Mangroves play a vital role in the health and well-being of both coastal communities and the global environment.
- They are often referred to as the "kidneys of the Earth" due to their ability to filter and purify water.
Body
Significance of Mangroves
- Mangroves are highly effective at removing pollutants and excess nutrients from the water. Their intricate root systems act like a sieve, trapping sediments and filtering out toxins and excess nutrients such as nitrogen and phosphorus. This helps to maintain the quality of the surrounding water and prevent harmful algal blooms that can cause fish kills and other environmental problems.
- Mangroves also provide important habitat and nursery grounds for a wide variety of fish, crustaceans, and other marine animals. The roots and branches of mangroves provide shelter and protection from predators, while the shallow water and abundant food resources make them an ideal breeding ground for many species. This makes mangroves important not only for the health of the coastal environment but also for the livelihoods and well-being of coastal communities.
- In addition to their ecological functions, mangroves are also important for mitigating the impacts of climate change. They are highly effective at sequestering carbon, with some estimates suggesting that they can store up to 10 times more carbon per unit area than most other terrestrial ecosystems. By storing carbon in their biomass and sediments, mangroves can help to reduce the amount of carbon dioxide in the atmosphere, thus mitigating the impacts of climate change.
- Despite their importance, mangroves are facing a range of threats, including deforestation, pollution, and climate change. Many mangrove forests have been cleared for development or aquaculture, while others have been degraded by pollution and sedimentation. As a result, it is essential that we take steps to protect and conserve these important ecosystems.
Conclusion
Mangroves are a vital component of the global environment and are often referred to as the "kidneys of the Earth" due to their ability to filter and purify water. They provide important habitat and nursery grounds for many marine species and are highly effective at sequestering carbon. However, they are facing a range of threats and it is important that we take steps to protect and conserve these unique and valuable ecosystems for future generations.