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How can sediment infilling eventually cause a lake to disappear?

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lake Lake Ann in North Cascades National Park, Washington, U.S., viewed from the park's Maple Loop Trail. The North Cascades National Park is a large wilderness area that preserves majestic mountain scenery, snowfields, glaciers, and other unique natural features.

Sediment infilling is a natural process that gradually reduces the depth of a lake, eventually leading to its physical disappearance. This process occurs through several mechanisms:12

Sedimentation: Rivers and streams transport clastic materials—such as clay, silt, and sand—into the lake basin. As the water enters the lake, its velocity decreases, causing these materials to settle on the bottom.34
Biological Enrichment: Over time, lakes accumulate organic debris from plant and animal matter. As a lake becomes more productive (eutrophic), bottom-dwelling plants spread throughout the littoral zone.12
Vegetation Encroachment: As the lake becomes shallower, the plant-choked littoral zone expands toward the center of the lake. In some cases, floating mats of vegetation, such as sphagnum moss, can grow from the surface down, while organic matter collects on the bottom, filling the basin from both directions.25
Succession: As the lake fills, it may transition into a marsh or pond, eventually becoming a meadow or forest as terrestrial vegetation takes over.26

Human activities, such as the addition of agricultural fertilizers or wastewater, can accelerate this process by increasing nutrient levels and biological production.1