Ecology Basics

📖 What is an ecosystem?

An ecosystem is a community of living organisms (biotic components) interacting with their non-living environment (abiotic components — soil, water, sunlight, temperature) as a functional unit. Ecosystems can range from a small pond to an entire forest or ocean.

🔗 Food chains and food webs

A food chain shows a linear sequence of energy transfer: Producers (plants, which convert sunlight to energy via photosynthesis) → Primary consumers (herbivores) → Secondary consumers (carnivores that eat herbivores) → Tertiary consumers (top predators). In reality, most ecosystems have interconnected food chains forming a food web, since most organisms eat and are eaten by more than one species.

📐 Ecological pyramids

Ecological pyramids visually represent the structure of an ecosystem at each trophic level:

• Pyramid of Numbers — count of organisms at each level.
• Pyramid of Biomass — total mass of organisms at each level.
• Pyramid of Energy — always upright, since energy is lost (mostly as heat) at each trophic transfer, following the 10% law — roughly only 10% of energy passes to the next trophic level.