Ecosystem

Definition

A functional unit comprising interacting organisms (biotic components) and their physical environment (abiotic components), linked by nutrient cycles and energy flows. In entomological and arachnological contexts, ecosystems are often analyzed at nested scales: individual organisms, populations, communities, and their interactions with habitat structure, climate, and resource availability.

Etymology

From Greek oikos (house, household) + systema (organized whole, system)

Example

A meadow ecosystem might include grasses and forbs (producers), aphids and leafhoppers (herbivores), lady beetles and damselflies (predators), dung beetles and carrion beetles (detritivores), and soil-dwelling springtails and mites (decomposers), all interacting with soil chemistry, moisture, and temperature.

Synonyms

• biological system
• ecological system

Related Terms

• Community
• Habitat
• Niche
• Trophic level
• Food web
• biome
• biodiversity
• Ecology
• Population
• species interaction

Usage Notes

Often contrasted with 'community' (biotic components only) and 'habitat' (physical environment only). Specialists distinguish ecosystem ecology (energy and nutrient fluxes) from community ecology (species interactions). Scale is relative: a rotting log, a pond, or a forest can each constitute an ecosystem depending on the research question.