Environmental engineering relies on our ability to understand complex environmental phenomena and how these interact with the human system over a wide range of scales. There are different kinds of human-environment interactions.

First, the quality of the environmental system affects the social system, e.g., pollution of air, water, and soil affects human health and well-being.

Second, human activities, in particular land-use change, affect the environmental system or ecosystem services. It is thus essential to analyze, model, and assess the effect of human activities on resource use and environmental pollution and determine the factors driving human behavior.
Third, there is reciprocity between the human and the environmental systems, including feedback loops. These different categories of interaction are understood by integrating both environmental and social dynamics in conceptual and simulation models, and data requirements. In particular, the use of big data and new digitalization tools will strongly drive research into human-environment interactions in the future.