Covers both inland salt flats (like Salar de Uyuni
乌尤尼盐沼) and coastal salt marshes. Compare
沼泽 (zhǎozé, 'swamp/marsh,' freshwater) and
盐田 (yántián, 'salt-evaporation pond,' a man-made facility for harvesting salt).
盐沼 is the natural saline ecosystem.