What Happens on Land Doesn't Stay on Land!
Aquatic ecosystems (lakes, rivers, and oceans) receive water from the surrounding landscape, an area of land known as the ecosystem's watershed.
But watersheds contribute much more than water to a lake, river, or ocean; for example, sediments, nutrients, and organic carbon also wash into aquatic ecosystems. These materials help nourish and sustain the productivity of aquatic ecosystems. However, humans have greatly modified watersheds and aquatic ecosystems with often detrimental consequences for water quality.