Presently, 58% of the U.S. population lives in urban areas; by 2030 it is estimated that 60% of the global population will live in a metropolitan setting. Interactions between non-living factors, such as sunlight or water, and biological factors, such as plants and microbes, take place in all environments, including cities. By concentrating humans and the resources they consume, metropolitan areas alter soil drainage, water flow, and light availability. Think of how architecture, such as sidewalks and rooftops, impacts the way rainwater is received and transported. Or the way garbage dumps and sewage plants centralize waste products.

Understanding how urban ecosystems function is integral to mitigating their negative effects on ecosystem services, assessing their impact on neighboring environments, and considering them in decision-making dialogue. Engaging urban dwellers is critical; their activities directly impact they way urban ecosystems function and they have a vested interest in maintaining the environmental integrity of the area they live in.