What is an ecosystem?

An ecosystem is fundamentally understood as a community of living organisms, such as plants, animals, and microorganisms, along with their physical environment, which includes components like air, water, soil, and climate. This definition highlights the intricate interactions and relationships that occur between the biotic (living) and abiotic (non-living) elements within a given environment.

These interactions are crucial for the flow of energy and cycling of nutrients, which all support the life processes of the organisms. For instance, plants convert sunlight into energy through photosynthesis, herbivores consume those plants, and predators feed on herbivores, forming a complex web of life that characterizes an ecosystem. Moreover, ecosystems can vary in size and can include diverse environments such as forests, deserts, wetlands, and urban settings, which all play an essential role in sustaining life on Earth.

In contrast, other options focus on more specific aspects or smaller components of ecology, such as groups of animals or individual organisms, without encompassing the broader, integrative concept of interactions between living beings and their environments that define an ecosystem.