Ecology is the study of the relationships between living organisms, including humans, and their physical environment; it seeks to understand the vital connections between plants and animals and the world around them. Ecology also provides information about the benefits of ecosystems and how we can use Earth’s resources in ways that leave the environment healthy for future generations.
An ecosystem is a complex unit where a community of organisms interacts with its physical environment. This includes all living organisms (biota) and the nonliving factors from which they obtain energy and nutrients. Within an ecosystem, organisms are organized into trophic levels, forming a food chain. Primary producers, like plants, harness solar energy through photosynthesis to create organic substances. Consumers, known as heterotrophs, then obtain energy by eating other organisms, directly or indirectly relying on these producers. Energy flows through the ecosystem, with a significant portion lost as heat at each trophic level. Ecosystems can be found in various forms, from forests and grasslands to aquatic environments like lakes and oceans.