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mads.xsd"><authority><topic authority="http://roble.intecca.uned.es/tematres/lem/">Ecosistemas</topic></authority><related type="narrower"><topic>Bentos</topic></related><related type="narrower"><topic>Comunidades vegetales</topic></related><related type="narrower"><topic>Simbiosis</topic></related><related type="other"><topic>Biosfera</topic></related><related type="other"><topic>Zonas climáticas</topic></related><related type="other"><topic>Ecología</topic></related><related type="other"><topic>Medio ambiente</topic></related><variant type="other"><topic>Ecosistemas naturales</topic></variant><variant type="other"><topic>Biocenosis</topic></variant><variant type="other"><topic>Sistemas ecológicos</topic></variant><variant type="other"><topic>Comunidades biológicas</topic></variant><variant type="other"><topic>Comunidades bióticas</topic></variant></mads>