. . . "The sum of nitrate, nitrite, and ammonium"@en . . "dissolved inorganic nitrogen"@en . "0001-01-01T00:00:00"^^ . "0001-01-01T00:00:00"^^ . "http://www.unisdr.org/files/7817_UNISDRTerminologyEnglish.pdf"@en .