Questions
Eco System 1. Discuss in detail about 'Eco-System'. 2. Discuss in detail the eco-system. 3. Discuss in detail the eco-system.
Eco-System:
Definition and Concept of Eco-System
- The term 'Ecosystem' was coined by Sir Arthur Tansley in 1935.
- An ecosystem is a structural and functional unit of nature where living organisms (biotic components) interact with each other and with the non-living (abiotic) environment.
- It includes all the organisms and the physical environment with which they interact, maintaining a dynamic balance.
Structure & Components of Ecosystem
1. Biotic Components
- Producers (Autotrophs): Mainly green plants and some bacteria that convert solar energy into chemical energy via photosynthesis.
- Consumers (Heterotrophs): Animals and other organisms that consume producers or other consumers (Herbivores, Carnivores, Omnivores).
- Decomposers (Saprotrophs): Microorganisms like bacteria and fungi that break down dead organic matter, recycling nutrients.
2. Abiotic Components
- Physical factors: Sunlight, temperature, water, air, minerals, soil, etc.
- Chemical factors: Nutrients like nitrogen, carbon, phosphorus, etc.
- Climatic factors: Rainfall, humidity, wind, etc.
Functions of Eco-System
1. Productivity
- Primary Productivity: Rate at which producers convert light energy to chemical energy.
- Secondary Productivity: Rate at which consumers convert energy from food into biomass.
2. Energy Flow
- Unidirectional: Solar energy → Producers → Consumers → Decomposers → Environment.
- Only about 10% of energy is transferred to next trophic level (10% law).
3. Nutrient Cycling (Biogeochemical Cycles)
- Continuous cycling of elements (carbon, nitrogen, phosphorus, water, etc.) between biotic and abiotic components.
4. Decomposition
- Breakdown and recycling of organic matter, replenishing nutrients.
5. Regulation (Homeostasis)
- Ecosystem maintains a balance through negative feedback mechanisms.
Types of Eco-System
1. Natural Ecosystems
- Terrestrial Ecosystems: Forests, grasslands, deserts, tundra.
- Aquatic Ecosystems: Freshwater (ponds, lakes, rivers), Marine (oceans, estuaries).
2. Artificial Ecosystems
- Created or modified by humans: Crop fields, aquariums, urban parks.
Key Concepts in Ecosystem
1. Food Chain
- Linear sequence of organisms where one is eaten by the next in the chain. E.g., Grass → Grasshopper → Frog → Snake → Hawk.
2. Food Web
- Network of interconnected food chains, depicting complex feeding relationships.
3. Ecological Pyramids
- Graphical representation of number, biomass or energy at each trophic level (Pyramid of Numbers, Biomass, Energy).
4. Trophic Levels
- Producers → Primary consumers → Secondary consumers → Tertiary consumers → Decomposers.
5. Ecological Succession
- Gradual and sequential change in species composition in an ecosystem over time (primary and secondary succession).
Ecosystem Services
- Provisioning Services: Food, water, timber, fiber, medicine.
- Regulating Services: Climate regulation, disease control, water purification, pollination.
- Supporting Services: Nutrient cycling, soil formation, primary production.
- Cultural Services: Recreation, spiritual and aesthetic benefits.
Importance of Ecosystem
- Maintains ecological balance and supports life on Earth.
- Supplies raw materials and resources for survival and development.
- Regulates biogeochemical cycles and climate.
- Protects against environmental hazards and disasters.
Threats to Ecosystems
- Deforestation and habitat loss.
- Pollution (air, water, soil).
- Climate change and global warming.
- Overexploitation of resources.
- Introduction of invasive species.
Conservation and Preservation Strategies
- Protected areas (National Parks, Wildlife Sanctuaries).
- Afforestation and reforestation.
- Sustainable resource utilization.
- Environmental Impact Assessment (EIA).
- Restoration ecology.
Conclusion
- India is rich in diverse ecosystems (Western Ghats, Himalayas, Sundarbans, etc.).
- Ecosystem-based approaches are included in government schemes like PMKSY, National Afforestation Programme, etc., to balance development with conservation.
Word Count - 500