zinc (172) zirconium (120) hyporheic zone processes -> groundwater and surface-water interaction (7) buffer zones -> administrative areas (1) demilitarized zones -> administrative areas (1) fault zones (4) free trade zones -> administrative areas (1) trade zones -> administrative areas (1) leased zones (government) -> administrative areas (1) neutral zones (political) -> administrative areas (1) zoological gardens -> parks (2) zoos -> parks (2)