How do restored wetlands specifically enhance natural flood storage capacity and attenuate peak flows in a downstream river system?

Restored wetlands specifically enhance natural flood storage capacity and attenuate peak flows in a downstream river system through a combination of hydrological and physical processes. Natural flood storage capacity refers to the ability of a landscape to temporarily retain floodwaters, preventing them from immediately entering the main river channel. Wetlands achieve this through their complex microtopography, which includes numerous shallow depressions, hummocks, and channels. These features create significant depressional storage, allowing large volumes of water to collect and be held within the wetland boundaries. Furthermore, wetland soils, often rich in organic matter due to accumulated plant decomposition, exhibit high porosity, which is the amount of empty space within the soil that can be filled with water. This high porosity facilitates increased infiltration, the process by which water from the surface penetrates into the ground. Organic matter acts like a natural sponge, significantly increasing the soil's water-holding capacity, allowing it to absorb and retain substantial amounts of water from precipitation and overflow. These interconnected mechanisms enable the wetland to temporarily hold a greater volume of water, effectively acting as a natural reservoir.