An ecosystem can be thought of as a natural functional unit in which living creatures (producers, consumers, and decomposers) interact with one another as well as with the physical environment. An ecosystem can be any size, but it typically consists of a small number of species. Through nutrient cycles and energy flows, biotic and abiotic components of the ecosystem are linked. Everything in an ecosystem is reliant on the other species and materials that make up the ecosystem. When one portion of an ecosystem is destroyed or removed, it affects the rest of the ecosystem. This article will explain to you about Ecosystem which will be helpful in preparing the Environment syllabus for the UPSC Civil service exam.

What exactly is an Ecosystem?

• An ecosystem is a geographical area in which plants, animals, and other species, as well as weather and topography, interact to generate a living bubble.
• Ecosystems can also be defined as the structural and functional units of ecology in which living species interact with one another and with their surroundings.
• An English botanist named A.G.Tansley created the term "ecosystem" in 1935.
• The biological and behavioural interactions between living and nonliving factors that make up the ecological system are also included in the definition of an ecosystem.
• Climate, soil, water, sun, earth, rocks, atmosphere, temperature, and humidity are examples of non-living characteristics of the environment.

Difference between Environment and Ecosystem

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Difference between Ecology and Ecosystem

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Components of Ecosystem

• The elements of ecosystems are primarily divided into two components such as abiotic and biotic components.
• The components of an ecosystem describe the ecosystem's structure, biological relationships, distribution, and environmental properties.
• The concept aims to characterize the environment's non-living (abiotic) and living (biotic) aspects, which are divided into four categories.

Biotic Components

• All living things in an ecosystem are referred to as biotic components.
• Biotic components can be classified as autotrophs, heterotrophs or saprotrophs (or decomposers) based on their nutritional needs.

Producers

• All autotrophs, such as plants, are producers.
• They are known as autotrophs because they can create food through photosynthesis.
• As a result, further up on the food chain, all other organisms rely on producers for sustenance.

Consumers

• Consumers, sometimes known as heterotrophs, are organisms that eat other organisms.
• Consumers are further divided into three categories: primary, secondary, and tertiary.
• Herbivores are always the primary consumers, and they rely on producers for food.
• For energy, secondary consumers rely on primary consumers. They can be either carnivorous or omnivorous.
• Organisms that rely on secondary consumers for food are known as tertiary consumers.
• Tertiary consumers might be omnivores as well. Some food chains contain quaternary consumers.
• For energy, these organisms prey on tertiary consumers. Furthermore, because they have no natural predators, they are frequently at the top of the food chain.

Decomposers

• Saprophytes, such as fungi and bacteria, are decomposers.
• They feed on dead and decaying organic substances directly.
• Decomposers are important for the ecology because they help recycle nutrients so that plants can utilise them again.

Abiotic Components

• All of the non-living things in an ecosystem are considered abiotic factors.
• Water, temperature, air, soil, rocks, atmosphere, minerals, nutrients, humidity, and other substances are examples.
• The Physico-chemical characteristics of a water supply, such as soil, can also affect whether it is fresh or salty.
• These are the components with which the biotic factors interact, and they are broadly divided into the following categories:
• Edaphic Factors: The chemical and physical features of the soil, such as minerals, soil profile, soil organic matter, soil moisture, and soil kinds, are all edaphic elements related with the composition and structure of the soil.
• Climatic Factors: The physical and climatic characteristics of the environment, such as atmospheric temperature, wind, humidity, and water, are referred to as climatic factors.

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Classification of Ecosystem

• A self-contained ecosystem is made up of living things and their nonliving environment.
• Natural and artificial ecosystems are the two types of ecosystems that can be found.
• Artificial ecosystems are natural areas that have been tainted by human intervention.
• Artificial lakes, reservoirs, townships, and cities are examples.

Natural Ecosystem

• Natural ecosystems are broadly divided into two categories. There are two types of ecosystems: terrestrial and aquatic .

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Terrestrial Ecosystem

• Terrestrial ecosystems are those that thrive on the land.
• A terrestrial ecosystem may contain water, however, these ecosystems are largely land-based.
• Forest ecosystems, desert ecosystems, grassland ecosystems, and mountain ecosystems are examples of these ecosystems.
• The decreased availability of water in terrestrial ecosystems, as well as the role of water as a limiting factor, distinguishes them from aquatic ecosystems.

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Aquatic Ecosystem

• An aquatic ecosystem is a type of ecosystem that is found in a body of water.
• The aquatic surroundings of their environment determine the nature and characteristics of communities of living or biotic species and non-living or abiotic forces that interact with and interrelate to one another.
• Marine ecosystems and freshwater ecosystems are two types of aquatic ecosystems.

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Functions of An Ecosystem

• The ecosystem's functional attributes keep the components working together.
• Ecosystem functions are natural processes or energy exchanges that occur in various plant and animal groups throughout the world's biomes.
• It can be broken down into three categories:
  • The flow of energy.
  • Cycling of nutrients (biogeochemical cycles).
  • Homeostasis (or cybernetic) or feedback control mechanisms.
  • Ecological succession, also known as ecosystem development, is the process by which an ecosystem develops.

Homeostasis in Ecosystem

• Ecosystems have the ability to maintain their equilibrium.
• They have the ability to control the structure and function of their own species.
• Homeostasis is the term for the ecosystem's ability to self-regulate.
• When an organism seeks to maintain a consistent internal (body) environment that allows all biochemical reactions and physiological activities to run as efficiently as possible, hence improving the species' overall 'fitness.' Homeostasis is the name given to this process.
• This consistency could be in terms of ideal temperature and osmotic concentration of body fluids, for example.
• Despite shifting external environmental variables that tend to upset the organism's homeostasis, the organism should endeavour to maintain a constant internal (inside the body) environment .

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Goods and Services Provided by Ecosystem

• Humans benefit from the biotic and abiotic components of an ecosystem in a variety of ways .
• These are critical to long-term well-being as well as future economic and social development.
• Food, water, timber, air purification, soil creation, and pollination are among few goods provided by ecosystems.
• Ecosystem services refer to the services that are necessary for life and biodiversity on Earth.
• The ecosystem services can be further divided into the following categories:
• Provisioning services
• Regulating services
• Support services
• Cultural services

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Ecotone

• An ecotone is a zone that serves as a transition or boundary between two ecosystems.
• A marshy area between a river and its riverbank is a common example.
• Ecotones are extremely important to ecology.
• As the area represents a transition between two ecosystems or biomes, it's only natural that it has a diverse range of fauna and plants because it's influenced by both ecosystems.
• Marshlands (between dry and wet habitats), mangrove forests (between terrestrial and marine ecosystems), grasslands (between desert and forest), and estuaries are all examples of ecotones (between saltwater and freshwater).
• Due to differences in climatic conditions on the slopes, mountain ranges can also generate ecotones.

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Niche

• A niche refers to how an organism or a population responds to, and changes, competition and resource distribution.
• It describes an organism's or a population's location in relation to other organisms or populations in a given ecosystem
• An ecosystem's biotic and abiotic components may have an impact on a niche.
• However, a species' niche in a given ecosystem will influence the characteristics of its surroundings, as these characteristics are critical to its existence.
• The role of the species (e.g., pollinator, decomposer), the food it eats, where it lives, where it reproduces, and its interactions with other species all contribute to its niche.

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Potential Threat to Ecosystems

Environmental Pollution

• Pollution of the air, land, water, and soil has a direct impact on the health of critical ecosystems.
• Pollution can discharge toxic compounds and damaging chemicals into the environment as a result of natural or artificial causes, endangering the health of living creatures and degrading the nature of non-living objects.
• Water pollution, for example, can disrupt the biological equilibrium in an aquatic system by increasing plant and nutrient development.
• It eventually results in the death of fish due to suffocation caused by dissolved oxygen depletion.
• Pollution has a variety of consequences, including interfering with natural ecosystem cycles such as the oxygen cycle, nitrogen cycle, water cycle, and food chain, resulting in ecosystem destruction.

Over-exploitation of Natural Resources

• The environment has been seriously harmed by the overexploitation of natural resources to the point of diminishing returns.
• Overhunting, overfishing, over mining, and overlogging have resulted in a decrease in community structures, population distributions and species breeding.
• Excessive fishing, for example, has resulted in the extinction of more than a third of all fish species, and some are now endangered.

Invasive Species

• Foreign species (Invasive Species) that enter an environment through human or natural means can cause substantial harm to the ecosystem's resident species.
• When this happens, native species may be completely wiped out or have a difficult time surviving.
• Invasive species often compete with native species for food, and they can also change the habitat.
• Ecosystems are gradually depleted, and species are completely eradicated as a result.
• The introduction of alien Nile Tilapia into Lake Victoria in the 1970s, according to the WWF (World Wide Fund for Nature), resulted in the loss of more than half of the local cichlid fish family.

Eutrophication

• Eutrophication is the overabundance of chemical nutrients in water bodies to the point where dense plant growth and algal blooms are encouraged.
• Depletion of oxygen, substantial deterioration of water quality, poisoning of seafood, and loss of recreational opportunities are all results of eutrophication, depending on the degree of eutrophication.
• As a result, it has an impact on fish and other aquatic life forms' survival.
• Toxic algal blooms in water bodies have harmed aquatic life and reduced the availability of clean water, posing a hazard to ecosystems.

Climate Change and Global Warming

• The ecosystems are under threat from climate change and global warming.
• Climate change and global warming have a direct impact on the abiotic factors that keep the biotic elements alive.
• The current rate of global warming is damaging and modifying coral reefs, mountain regions, and water cycles, all of which are essential ecological resources.
• Different species, for example, require different abiotic elements to thrive.
• If global warming and climate change continue, 10% of all species on the planet could go extinct by 2050.
• Thus the changes in the natural ecosystem pose a threat to biodiversity around the world and have ramifications for global food production.

Conclusion

According to the World Economic Forum (WEF), human activities put 58.4 % of Earth's terrestrial ecosystems under "moderate or acute" strain during the same time period. Every organism in an ecosystem has a certain role and function. As a result, upsetting an ecosystem's balance will be disastrous for all living things that rely on it. On a much larger scale, the Earth can be described as an ecosystem. External elements such as pollution from carbon dioxide and methane disrupt the ecosystem's balance to the point where it affects everyone who lives there.

FAQs

MCQs

1. Which of the following is NOT a biotic component of an ecosystem?

A) Plants
B) Animals
C) Soil
D) Microorganisms

2. What is the role of decomposers in an ecosystem?

A) Producing food
B) Consuming plants
C) Breaking down dead organisms
D) Providing shelter

3. What type of ecosystem is a forest?

A) Natural
B) Artificial
C) Urban
D) Agricultural

4. How do plants contribute to the ecosystem?

A) As primary producers
B) As decomposers
C) As predators
D) As parasites

5. What is an example of an artificial ecosystem?

A) Rainforest
B) Pond
C) Aquarium
D) Desert

GS Mains Questions and Answers

Q1: Explain the structure of an ecosystem and how energy flows through it.

Answer: An ecosystem consists of biotic (living) and abiotic (non-living) components. Biotic components include producers (plants), consumers (animals), and decomposers (fungi and bacteria), while abiotic components consist of sunlight, water, air, and soil.

Energy flows through an ecosystem in a unidirectional manner, starting with the producers. Plants, as primary producers, convert solar energy into chemical energy through photosynthesis. Herbivores, or primary consumers, feed on plants and obtain this energy. Carnivores, or secondary and tertiary consumers, feed on herbivores and other animals. Finally, decomposers break down dead organisms, returning nutrients to the soil, completing the cycle of energy transfer in an ecosystem.

Q2: Discuss the significance of biodiversity in maintaining ecosystem balance.

Answer: Biodiversity is crucial for maintaining the balance and stability of ecosystems. It enhances ecosystem productivity, as each species plays a unique role in ecological processes such as pollination, nutrient cycling, and food chain regulation. Higher biodiversity ensures that ecosystems are more resilient to environmental changes, such as climate shifts or natural disasters, and can recover more quickly from disturbances.

A diverse ecosystem also provides a wider range of ecosystem services, including clean air and water, soil fertility, and food security. The loss of biodiversity due to human activities, such as deforestation and pollution, threatens the ability of ecosystems to function properly and deliver these essential services.

Q3: How do human activities disrupt ecosystem services, and what measures can be taken to mitigate these impacts?

Answer: Human activities such as deforestation, industrial pollution, overfishing, and urbanization disrupt ecosystem services by altering natural processes and reducing biodiversity. These activities lead to habitat destruction, soil degradation, water pollution, and the extinction of species, affecting the ecosystem's ability to regulate climate, purify water, and sustain food production.

To mitigate these impacts, measures such as sustainable land use practices, afforestation, conservation of biodiversity hotspots, and the implementation of stringent environmental regulations are necessary. Public awareness and community participation in conservation efforts can also play a crucial role in preserving ecosystem services for future generations.

Previous Year Questions on Ecosystem

1. UPSC CSE Prelims 2020:

Question: Which of the following components is NOT a part of the biotic environment?

A) Plants
B) Animals
C) Microorganisms
D) Water

Answer: D

Explanation: Water is an abiotic component of the ecosystem. Biotic components include living organisms such as plants, animals, and microorganisms.

2. UPSC CSE Mains 2019 (GS Paper 3):

Question: "Human activities have led to the degradation of ecosystems across the world." Discuss the causes of ecosystem degradation and suggest measures to restore ecological balance.

Answer: Ecosystem degradation is primarily caused by human activities such as deforestation, overgrazing, industrial pollution, and urbanization. These activities lead to the destruction of habitats, loss of biodiversity, soil erosion, and water contamination. Additionally, climate change exacerbates ecosystem degradation by causing shifts in temperature and precipitation patterns.

Restoring ecological balance requires a multifaceted approach, including reforestation, the conservation of wildlife habitats, the reduction of pollution, and the sustainable management of natural resources. International cooperation and the enforcement of environmental laws are also critical for ensuring long-term ecological stability.