From Academic Kids
Environmental science is the science of the interactions between the physical, chemical, and biological components of the environment, including their effects on all types of organisms but more often refers to human impact on the environment.
It is an interdisciplinary area of study that applies knowledge from other scientific and socal disciplines. Basic physics is used to understand material and energy transfers. Chemistry is essential to understanding the components that drive changes to each part of the environment, as well as the entire environmental system. Environmental science also relies on other disciplines, such as the social sciences, environmental law, and economics to address the interactions between humans and the natural environment.
Significantly, it is important to distinguish between "environmental science" and "ecology": the two disciplines embody very different foci of investigation.