This optional theme focuses on water on the land as a scarce resource. It considers the ways in which humans respond to the challenges of managing the quantity and quality of freshwater, as well as the consequences (whether intended or unintended, positive or negative) of management. The theme includes both the physical geography of freshwater (basic hydrology and floods) and human impacts on water quality.
This theme should include the study of at least one detailed case study at the drainage basin level. Reference should be made to additional examples, at a range of scales, in less depth, wherever appropriate.