What happens to wetlands when reservoirs trap sediment?

When reservoirs trap sediment, the natural flow of sediment that would normally nourish and maintain wetlands is interrupted. Wetlands depend on a supply of sediment to help sustain their ecosystem, as sediment contributes to the elevation and structure of these environments. Over time, without the influx of sediment, wetlands can begin to fill in with organic matter or compacted soil from the surrounding area, leading to a gradual accumulation that fills the wetland.

This process can result in the wetlands becoming shallower and eventually converted into a different type of habitat, such as marshes or grasslands, or they may even disappear entirely if enough sediment is trapped. The lack of sediment can also affect the biodiversity of the wetland system, as many aquatic species rely on specific water depths and substrate conditions that can be altered when sediment supply is reduced.