@prefix envthes: . @prefix skos: . @prefix dc: . @prefix xsd: . @prefix owl: . envthes:22226 skos:prefLabel "secchi depth"@en ; dc:modified "2018-12-18"^^xsd:date ; skos:note "[controlled by ] Alessandro Oggioni 23.05.2013 , \"[controlled by ] Alessandro Oggioni 23.05.2013"@en ; a skos:Concept ; skos:altLabel "secchi"@en ; skos:exactMatch ; skos:inScheme envthes: ; skos:broader envthes:20935 ; dc:creator "herbert.schentz@umweltbundesamt.at"@en ; dc:created "2016-03-31"^^xsd:date ; skos:definition "n. is a measure of water trasparency in oceans and lakes. N. is measured by Secchi disk created in 1865 by Pietro Angelo Secchi. Secchi disk is a circular disk mounted on a pole or line, and the depth at which the pattern on the disk is no longer visible is taken as a measure of the transparency of the water."@en ; skos:scopeNote "US LTER controlled vocabulary"@en . envthes: skos:prefLabel "EnvThes"@en ; a owl:Ontology, skos:ConceptScheme . envthes:20935 skos:prefLabel "variable"@en ; a skos:Concept ; skos:narrower envthes:22226 .