diff --git a/EnvThes/30283.ttl b/EnvThes/30283.ttl
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+@prefix envthes: <http://vocabs.lter-europe.net/EnvThes/> .
+@prefix skos: <http://www.w3.org/2004/02/skos/core#> .
+@prefix iadopt: <https://w3id.org/iadopt/ont/> .
+@prefix dc: <http://purl.org/dc/terms/> .
+@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
+@prefix owl: <http://www.w3.org/2002/07/owl#> .
+
+envthes:10347
+  skos:prefLabel "dissolved"@en ;
+  a iadopt:Constraint, skos:Concept ;
+  iadopt:constrains envthes:20828 .
+
+envthes:20935
+  skos:prefLabel "variable"@en ;
+  a skos:Concept ;
+  skos:narrower envthes:30283 .
+
+envthes:20828
+  skos:prefLabel "plumb"@ro, "svinec"@sl, "olovo"@sk, "olovo"@hr, "olovo"@cs, "الرصاص"@ar, "lyijy"@fi, "svins"@lv, "plomb"@fr, "lead"@en, "lood"@nl, "piombo"@it, "švinas"@lt, "Олово"@bg, "Blei"@de, "bly"@sv, "bly"@no, "bly"@da, "chumbo"@pt, "plii"@et, "μόλυβδος"@el, "plomo"@es, "ołów"@pl, "ólom"@hu ;
+  a skos:Concept .
+
+envthes:30283
+  iadopt:hasMatrix envthes:30284 ;
+  dc:created "2022-03-30"^^xsd:date ;
+  skos:prefLabel "concentration of dissolved lead in river water"@en ;
+  skos:broader envthes:20935 ;
+  dc:modified "2022-03-30"^^xsd:date ;
+  iadopt:hasObjectOfInterest envthes:20828 ;
+  skos:altLabel "mass density of dissolved lead in water"@en ;
+  dc:creator <https://orcid.org/0000-0003-2195-3997> ;
+  a skos:Concept ;
+  skos:narrower envthes:30285 ;
+  iadopt:hasProperty <http://qudt.org/vocab/quantitykind/MassDensity> ;
+  iadopt:hasConstraint envthes:10347 ;
+  skos:inScheme envthes: .
+
+iadopt:hasProperty
+  rdfs:comment "A Variable has a Property that characterizes an Entity." ;
+  rdfs:label "hasProperty" .
+
+iadopt:hasMatrix
+  rdfs:subPropertyOf iadopt:hasContextObject ;
+  rdfs:comment "A Variable might have an Entity in which the ObjectOfInterest is contained." ;
+  rdfs:label "hasMatrix" .
+
+envthes:
+  skos:prefLabel "EnvThes"@en ;
+  a owl:Ontology, skos:ConceptScheme .
+
+iadopt:hasObjectOfInterest
+  rdfs:comment "A Variable has an Entity whose Property is observed." ;
+  rdfs:label "hasObjectOfInterest" .
+
+envthes:30284
+  skos:prefLabel "river water"@en ;
+  a skos:Concept .
+
+iadopt:hasConstraint
+  rdfs:comment "A Variable has a Constraint, that confines an Entity involved in the observation." ;
+  rdfs:label "hasConstraint" .
+
+envthes:30285
+  skos:prefLabel "monthly mean concentration of dissolved lead in river water in microgram per litre"@en ;
+  a skos:Concept ;
+  skos:broader envthes:30283 .