New Environment Class 03

 New Environment Class 03

BRIEF DISCUSSION OF THE PREVIOUS CLASS (5:12 P.M.)

FUNCTIONS IN ECOSYSTEM (5:24 P.M.)

• Biotic interaction
• Types of Organisms in Ecosystem
• (a)Producers
• These are capable of photosynthesis.
• For example, plants and phytoplankton.
• (b)Herbivores
• These are plant-eating organisms.
• For example, Cow, goat, etc.
• (c)Carnivores
• They feed on herbivores.
• For example, lion, wolf, etc.
• (d)Detrivores/Scavengers
• They feed on dead matter.
• For example, Hyena, Vultures, etc.
• (e)Nectarivores
• They feed on nectar.
• For example, Hummingbird, Sunbird, etc.
• (f)Frugivores
• They eat fruits.
• For example, Parrots, Parakeets, Great Hornbill, Monkeys, etc.
• (g)Gramivores
• They feed mainly on grass.
• For example, Sparrow, Munia, Bluethroat birds, Deers, Horses, Cows, Elephant, Rhinoceros, Indian Bison, etc.
• Types of Organisms Based on Roles
• (a)Flagship species
• Species selected to act as an ambassador, icon, or symbol for the defined habitat, issue, or campaign.
• They are relatively large and charismatic.
• For example, the Tiger, the Great Indian Bustard (Heaviest Flying Bird), etc. 
• (*Note: Sarus Crane is the tallest flying bird.)
• (b)Keystone Species
• It is a species that plays an essential role in the functioning or structure of the ecosystem. Its disappearance may cause significant change.
• They have a disproportionately large impact on the ecosystem, compared to their abundance.
• For example, Wolves in Yellowstone National Park (Yellowstone National Park is the first national park in the world.), Honey Bees, Top Predators, Elephants, etc.
• Elephants are called ecosystem engineers.
• (c)Indicator Species
• They indicate certain processes in the ecosystem.
• They are used to assess the environmental condition or the quality of an ecosystem.
• For example, Lichens indicate air pollution, River Dolphins indicate water pollution, Corals indicate sedimentation, Blackbucks indicate the health of grassland, Himalayan Monal indicates the health of the Himalayan ecosystem, etc.
• (d)Umbrella Species
• These are the dominant species in the ecosystem and are representatives of that ecosystem.
• By protecting the umbrella species, all other species can be easily protected.
• For example, Corals, Kelps, and top predators.
• Ecosystem Services (6:05 P.M.)
• four types of services are provided by the ecosystem:
• (a)Provisioning Services
• The "products" are obtained from the ecosystem.
• For example, Foods, Fibers, Ornamentals, Minerals, etc.
• (b)Regulating Services
• The benefits obtained from the regulation of ecosystem processes.
• For example, Climate Regulation, Flood Prevention, etc.
• (c)Cultural Services
• These refer to the non-material services obtained from the ecosystem.
• For example, Educational, recreational, etc.
• (d)Supporting Services
• These services are necessary for the production of all other ecosystem services.
• For example, Biodiversity, Nutrient Cycle, etc.

BIOGEOCHEMICAL CYCLES (6:11 P.M.)

• The flow of different chemical elements and compounds between different organisms and the physical environment is called as Biogeochemical Cycle.
• These are classified into the gaseous cycles and sedimentary cycles.
• (a)Gaseous Cycle
• In this, the reservoir pool is the atmosphere.
• For example, Carbon Cycle, Nitrogen Cycle, Water Cycle, and Oxygen Cycle.
• (b)Sedimentary Cycle
• The reservoir pool is in the Earth's crust or lithosphere.
• For example, the Sulphur Cycle and Phosphorous Cycle.

WATER CYCLE (6:21 P.M.)

• The water vapour converts into water through the process of condensation.
• This water accumulates around the hygroscopic particles, leading to cloud formation.
• The precipitation would lead to the falling of the water on the surface.
• When water vapour condenses on the ground, it may result in different condensation forms like fog, mist, dew, and frost.
• The water converts into water vapour by absorbing the heat. This process is called evaporation. 
• 

CARBON CYCLE (6:30 P.M.)

• The carbon dioxide present in the atmosphere enters the plants through the process of photosynthesis.
• The equation of photosynthesis is 6CO2+ 6H2O+ Sunlight -> C6H12O6+ 6O2.
• The plants store it in the form of carbohydrates.
• The consumers consume the plants, there by it goes into the consumers.
• The consumers give out carbon dioxide by the process of respiration.
• The plants also perform the respiration to release the carbon dioxide.
• Plants and consumers after their death convert into the soil organic matter.
• This soil organic matter decomposes to release the carbon into the atmosphere.
• Some soil organic matter will convert into fossil fuel.
• This fossil fuel on combustion will release the carbon into the atmosphere.
• The oceans are capable of absorbing the carbon dioxide. They release it back, once they get saturated.
• 

OXYGEN CYCLE

• Plants convert the atmospheric carbon dioxide into the atmospheric oxygen.
• This is taken by the plants and animals which convert it into carbon dioxide (Respiration Process).
• Also, the oxides release the oxygen into the atmosphere.

NITROGEN CYCLE (7:06 P.M.)

• Nitrogen is present abundantly in the atmosphere.
• The conversion of nitrogen into ammonia is called Nitrogen Fixation.
• Nitrogen Fixation is carried out by free-living bacteria in the soil. For example, Azatobacter and Clostridium.
• Nitrogen Fixation is carried out by the symbiotic microbes as well. For example, Rhizobium and Blue Green Algae (Anabena and Spirulena).
• Nitrogen Fixation happens naturally during the lightening as well.
•  It can be carried out by industrial processes as well.
• Ammonia is converted into Nitrite and Nitrate through the process of Nitrification.
• Nitrosomonas converts the ammonia into nitrites.
• Nitrobacter converts the nitrite into nitrates.
• The nitrate is converted into ammonia through the process of Ammonification.
• Nitrate is converted into nitrogen through the process of Denitrification.
• Pseudomonas converts the nitrites and nitrates into the nitrogen.
• 
• Fossil fuels also contain some nitrogen compounds. On combustion, the oxides of the nitrogen reach the atmosphere.
• This further comes down with rain in the form of nitric acid.

PHOSPHOROUS CYCLE (7:28 P.M.)

• The phosphorous is stored in the rocks.
• The phosphorous is released into the soil through the processes of weathering, erosion, etc.
• In the soil, the phosphorous is present in the form of phosphates.
• The plants take this phosphate through the process of assimilation.
• Through consumption, it travels higher in the food cycle.
• From the consumers, it reaches the soil through the process of excretion and decomposition.
• Rain, rivers, and other such agents take away the phosphorous from the soil and deposit it into the basin.
• Through the process of lithification, it again gets stored in the rocks.

SULPHUR CYCLE 

• There is an interaction with the atmosphere, but the reservoir is in the lithosphere.
• It is stored in the form of organic and inorganic forms.
• In the organic form,  it is stored in the form of coal, petroleum, and peat.
• In the inorganic form, it is stored in the form of sulfates and sulfides.
• 

TIGERS (7:40 P.M.)

• The various statuses are Not Evaluated, Data Insufficient, Least Concern, Near Threatened, Vulnerable, Endangered, Critically Endangered, Extinct in Wild, and Extinct.
• Big cats in India are Lion, Tiger, Cheetah, Snow Leopard, and Leopard.
• Jaguar and Puma are not present in India.
• The IUCN status of the tiger is endangered.
• Tiger is in Appendix 1 of the CITES.
• There are several subspecies of tiger,
• It is present in 13 countries, where it is found in the wild. These countries are called Tiger-Range countries.
• India, Nepal, Bangladesh, Bhutan, Myanmar, Thailand, Laos, Vietnam, Cambodia, Malaysia, Indonesia, China, and Russia are such countries.
• India hosts 70% of the world's tigers.
• The various subspecies of tigers can be classified into continental tigers and Island tigers.
• The Royal Bengal Tiger is a continental tiger.
• The Indo-China Tiger is also a continental tiger. 
• The Malayan Tiger is a continental tiger.
• Sumatran and Javan tigers are island tigers. 
• The Bali Tiger is extinct.
• China has a South-China tiger, which is a continental tiger.
• The Amur/Siberian tiger is found in Siberia. It is the biggest species of tiger.
• The tiger is the largest of all the big cats.
• The tiger is very important as it is a keystone, flagship, and umbrella species.

THE TOPIC FOR THE NEXT CLASS: DIFFERENT TYPES OF ECOSYSTEMS, BIOMES, AND WETLANDS.

Here are 30 one-line questions with answers

1. What are producers in an ecosystem?

   • Organisms capable of photosynthesis, like plants and phytoplankton.

2. What are herbivores?

   • Plant-eating organisms, e.g., cow and goat.

3. What do carnivores feed on?

   • They feed on herbivores, e.g., lion and wolf.

4. What do detritivores or scavengers feed on?

   • Dead organic matter, e.g., hyenas and vultures.

5. What do nectarivores feed on?

   • Nectar, e.g., hummingbirds and sunbirds.

6. What are frugivores?

   • Organisms that eat fruits, e.g., parrots and monkeys.

7. What are gramivores?

   • Organisms that primarily feed on grass, e.g., deer and elephants.

8. What is a flagship species?

   • A species selected as a symbol for a specific habitat or conservation effort, e.g., the tiger.

9. What is a keystone species?

   • A species with a disproportionately large impact on its ecosystem, e.g., elephants and wolves.

10. What are indicator species?

    • Species used to assess environmental conditions, e.g., lichens indicating air pollution.

11. What is an umbrella species?

    • A species whose protection ensures the conservation of other species in its ecosystem, e.g., corals and top predators.

12. What are provisioning services in ecosystems?

    • Products obtained from ecosystems, e.g., food and minerals.

13. What are regulating services in ecosystems?

    • Benefits from the regulation of ecosystem processes, e.g., climate regulation and flood prevention.

14. What are cultural services in ecosystems?

    • Non-material benefits from ecosystems, e.g., recreational and educational services.

15. What are supporting services in ecosystems?

    • Services necessary for other ecosystem services, e.g., biodiversity and nutrient cycling.

16. What is a biogeochemical cycle?

    • The flow of chemical elements between organisms and the environment.

17. What are the two types of biogeochemical cycles?

    • Gaseous cycles (e.g., carbon cycle) and sedimentary cycles (e.g., phosphorus cycle).

18. Where is the reservoir pool in a gaseous cycle?

    • The atmosphere.

19. Where is the reservoir pool in a sedimentary cycle?

    • The Earth's crust (lithosphere).

20. What process converts water vapor into water in the water cycle?

    • Condensation.

21. What process converts water into water vapor in the water cycle?

    • Evaporation.

22. What process releases carbon dioxide into the atmosphere through plant and animal respiration?

    • Respiration.

23. What is net primary productivity (NPP) in an ecosystem?

    • Gross primary productivity (GPP) minus energy loss due to respiration.

24. What role do oceans play in the carbon cycle?

    • Oceans absorb and release carbon dioxide.

25. What is nitrogen fixation?

    • The conversion of atmospheric nitrogen into ammonia, carried out by bacteria.

26. Which organisms perform nitrogen fixation?

    • Free-living bacteria (e.g., Azotobacter) and symbiotic microbes (e.g., Rhizobium).

27. What is denitrification?

    • The process by which nitrates are converted back into nitrogen gas by bacteria like Pseudomonas.

28. Where is phosphorus stored in the phosphorus cycle?

    • In rocks, released through weathering.

29. What are the two main forms of sulfur stored in the lithosphere?

    • Organic forms (e.g., coal) and inorganic forms (e.g., sulfates).

30. What is the IUCN status of the tiger?

• Endangered.

Q11. Explain different types of species in an ecosystem with examples. (150 words/10 Marks)

In an ecosystem, species can be classified based on their roles and ecological importance:

1. Flagship Species: These species serve as symbols or ambassadors for a specific habitat or environmental cause. They are usually large and charismatic, capturing public attention. Example: The Tiger, Great Indian Bustard.

2. Keystone Species: These are species that play a critical role in maintaining the structure and functioning of the ecosystem. Their removal can lead to significant changes. Example: Wolves in Yellowstone National Park, Honey Bees, Elephants (ecosystem engineers).

3. Indicator Species: These species provide insights into the environmental health of an ecosystem by signaling certain conditions. Example: Lichens (air pollution), River Dolphins (water pollution), Himalayan Monal (health of the Himalayan ecosystem).

4. Umbrella Species: Protecting these species ensures the conservation of other species in the ecosystem. Example: Corals, Kelps, and top predators like tigers.

These species contribute to ecosystem stability and biodiversity conservation, making them vital for ecological management.

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Q12. Write a short note on the following: (150 words/10 Marks)

1. Nitrogen Cycle:

The nitrogen cycle is essential for converting atmospheric nitrogen (N₂) into forms usable by living organisms. The key steps include:

• Nitrogen Fixation: Atmospheric nitrogen is converted into ammonia (NH₃) by nitrogen-fixing bacteria such as Azotobacter (free-living) and Rhizobium (symbiotic with legumes).
• Nitrification: Ammonia is oxidized into nitrites (NO₂⁻) by Nitrosomonas and further into nitrates (NO₃⁻) by Nitrobacter.
• Assimilation: Plants absorb nitrates and incorporate them into organic compounds like proteins.
• Ammonification: Decomposition of dead organisms converts organic nitrogen back into ammonia.
• Denitrification: Bacteria like Pseudomonas convert nitrates back into nitrogen gas (N₂), returning it to the atmosphere.

This cycle maintains the balance of nitrogen in ecosystems, crucial for plant and animal life.

2. Phosphorus Cycle:

The phosphorus cycle involves the movement of phosphorus through the lithosphere, hydrosphere, and biosphere, without a gaseous phase.

• Weathering: Phosphates are released from rocks through weathering and enter the soil.
• Absorption: Plants assimilate phosphates from the soil, incorporating them into organic compounds.
• Consumption: Herbivores and carnivores obtain phosphorus by consuming plants and other animals.
• Decomposition: After death, organisms decompose, returning phosphorus to the soil.
• Sedimentation: Some phosphorus is carried by rivers to oceans, where it forms sediment, eventually becoming rock again through lithification.

Phosphorus is a crucial nutrient for biological molecules like DNA and ATP, playing a vital role in cellular energy transfer and genetic information.

Q1. What is an ecosystem? Discuss the structure and function of the ecosystem. What are ecosystem services? List a few examples for the same. (150 words /10 marks)

An ecosystem is a community of living organisms (biotic components) interacting with non-living (abiotic) components like air, water, and soil in a particular area. It involves the flow of energy and the cycling of nutrients that sustain life.

Structure of an Ecosystem:

• Biotic Components:
  • Producers: Autotrophs like plants and algae that perform photosynthesis.
  • Consumers: Herbivores, carnivores, and omnivores that feed on producers and other consumers.
  • Decomposers: Organisms like fungi and bacteria that break down dead matter.
• Abiotic Components: These include sunlight, temperature, water, soil, and minerals.

Function of an Ecosystem:

• Energy Flow: Energy enters through producers via photosynthesis and flows through various trophic levels (herbivores, carnivores) following the 10% rule.
• Nutrient Cycling: Elements like carbon, nitrogen, and phosphorus circulate between living and non-living components through biogeochemical cycles.

Ecosystem Services: Ecosystem services are benefits humans derive from ecosystems. These include:

• Provisioning Services: Food, water, wood, and fiber.
• Regulating Services: Climate regulation, flood control, and air purification.
• Cultural Services: Recreation, education, and aesthetic value.
• Supporting Services: Soil formation, nutrient cycling, and biodiversity maintenance.

Examples: Wetlands regulate floods, forests provide oxygen, and coral reefs support marine biodiversity.