Quivira's wetlands are unique due to the high concentration of salt in many areas. Subterranean salt deposits are near enough to the surface in the Quivira area to affect the groundwater that percolates to the surface. Salinity (or salt) levels in the water varies depending on rainfall, runoff from rainfall, and the depth of the water.
Sand Flats in Salt Marsh
Many areas have a high enough salinity to support salt-tolerant plant species such as inland salt grass (Distichlis spicata), alkali sacaton (Sporobolus airoides), and seepweed (Suaeda caceoliformis).

Salt Grass (Distichlis spicata)Salt crystals on sand at Little Salt Marsh