Environmental science

Ecosystems, biodiversity, population dynamics, and resource management

What is environmental science?

Environmental science studies how natural systems — ecosystems, resources, and the physical environment — work, and how human activity interacts with and affects them. It draws together ideas from biology, geology, and chemistry (including the chemical mechanisms covered in the Environmental Chemistry article) to understand the environment as a connected whole.

Ecosystems: living things and their surroundings

An ecosystem is a community of living organisms interacting with each other and with the non-living parts of their environment — soil, water, air, and sunlight. Energy flows through an ecosystem in a fairly consistent pattern: plants capture energy from sunlight, plant-eating animals get energy by eating plants, and predators get energy by eating other animals, with each step losing some energy as heat. Understanding these energy flows and relationships helps explain why ecosystems are structured the way they are, and how disturbing one part of the system can ripple outward to affect others.

Biodiversity

Biodiversity refers to the variety of living things in a given area or across the whole planet — the number of different species, but also the genetic variation within species and the variety of ecosystems themselves. Greater biodiversity generally makes an ecosystem more resilient, better able to withstand disturbances like disease, drought, or other environmental change, since a wider variety of species increases the chance that some will cope well with whatever challenge arises.

Natural resources and sustainability

Natural resources are materials or services provided by the environment that people use — water, timber, fish, fertile soil, and much more. Some resources renew themselves over time if not used faster than they can regenerate (renewable resources, like forests or fish populations); others exist in a fixed, finite supply and cannot be replenished on any meaningful human timescale (nonrenewable resources, like fossil fuels and many minerals). Managing resources sustainably means using them at a rate that doesn't permanently deplete or degrade them for the future.

Why environmental science matters

Environmental science guides decisions about resource management, conservation of threatened species and habitats, and assessing how proposed projects (like a new dam, mine, or development) are likely to affect the surrounding environment before those projects are built.