Q.By taking a small pond as an example, write down a complex interaction in an aquatic ecosystem.

Mangrove vegetation grows in saline coastal/tidal mudflats; in India the largest is the Sundarbans.

Mangroves are salt-tolerant (halophytic) forests of the intertidal zones of tropical coasts and deltas. They show adaptations such as pneumatophores (breathing roots) and vivipary.

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An aquarium is a human-constructed, artificial ecosystem, unlike desert, river and estuary, which are natural ecosystems.

Ecosystems can be natural (forest, desert, river, estuary, ocean) or man-made/artificial (crop fields, gardens, and aquaria). An aquarium is a man-made ecosystem, set up and maintained by humans, containing water, aquatic organisms …

Every ecosystem has two fundamental components — the biotic community of living organisms and the abiotic physical/chemical environment — that interact and exchange matter and energy.

An ecosystem is defined as a functional unit of nature in which living organisms interact among themselves and with their non-living surroundings. Its two components are: (1) the biotic component — producers, consumers, and decomposers; and (2) the abiotic component — physical and chemical factors such as temperature, water, soil, light, and inorganic/organic nutrients. Plants and animals (a …

An ecosystem is a self-sustaining functional unit combining a biological community with its physical environment, linked by flows of energy and cycling of matter.

An ecosystem is defined as a structural and functional unit of nature in which a community of living organisms (plants, animals, and microorganisms) interacts among themselves and with the surrounding non-living (physical and chemical) environment, through the continuous flow of energy (unidirectional, from sunlight) and the cycling of matter/nutrients (biogeochemical cycles). Ecosystems can range in scale from a small pond …

At deep-sea hydrothermal vents, chemosynthetic bacteria replace sunlight-dependent plants as the ecosystem's primary producers.

In almost all ecosystems, sunlight captured by photosynthetic producers is the ultimate source of energy that drives the food chain. An exception occurs in deep-sea hydrothermal-vent ecosystems, located far below the ocean's photic zone where no sunlight penetrates. Here, the primary producers are chemosynthetic (chemoautotrophic) bacteria, which do not photosynthesise but instead obtain energy by oxidising inorganic chemicals — chiefly hydrogen sulphide (H₂S) released from the vents — to synthesise …

Large, complex ecosystems with minimal external disturbance and greater buffering capacity — like the ocean — are the most stable.

Stability of an ecosystem refers to its ability to resist change (resistance) and to return to its original state after a disturbance (resilience). Several factors increase ecosystem stability:

• Large size/volume, which buffers against sudden environmental fluctuations (temperature, pH, salinity change slowly).
• High species diversity and complex food webs, which provide multiple alternative pathways of energy flow if one species is affected.
• Minimal direct human interference compared to terrestrial ecosystems. …