ecology

Ecology is the scientific study of the relationships between organisms and their environment. It examines how organisms interact with one another and with the physical surroundings that provide air, water, nutrients, and habitat. The field considers both biotic components, such as predators, prey, and symbionts, and abiotic factors, including climate, soil, and sunlight, and how energy and matter move through ecosystems.

Ecology organizes life into a hierarchy: individuals, populations, communities, ecosystems, landscapes, and the biosphere. Central concepts include niches, competition, predation, symbiosis, and succession. Energy flows through ecosystems in food webs, with producers capturing solar energy and transferring it through consumers and decomposers. Matter cycles through ecosystems by processes such as photosynthesis, respiration, decomposition, and nutrient cycling.

Key branches include population ecology, which studies how and why populations grow or shrink; community ecology, which looks at species interactions; ecosystem ecology, which emphasizes energy flow and nutrient cycling; landscape ecology, which considers spatial patterns at larger scales; and conservation and restoration ecology, which address biodiversity loss and ecosystem restoration.

Research methods range from field observations and experiments to mathematical modeling and remote sensing. Human activities—from habitat destruction and pollution to climate change and invasive species—profoundly affect ecological patterns and ecosystem services, which include food, clean water, pollination, and climate regulation. Ecology informs conservation, sustainable resource use, and the management of natural and managed ecosystems.