<http://aims.fao.org/aos/agrovoc/xDef_660ba04f> <http://www.w3.org/1999/02/22-rdf-syntax-ns#value> "The chart datum is the level of water that charted depths displayed on nautical charts are measured from. The chart datum is generally a tidal datum; that is, a datum derived from some phase of the tide. Common chart datums are lowest astronomical tide and mean lower low water."@en .
<http://aims.fao.org/aos/agrovoc/xDef_660ba04f> <http://purl.org/dc/terms/created> "2022-05-12T15:14:07"^^<http://www.w3.org/2001/XMLSchema#dateTime> .
<http://aims.fao.org/aos/agrovoc/xDef_660ba04f> <http://purl.org/dc/terms/source> <http://wiki.gis.com/wiki/index.php/Chart_datum> .