1. A method for generating and managing polyhierarchical metadata descriptions of artifacts using multiple standard metadata schemas, the method comprising: registering each of a plurality of standard metadata schemas, the registering comprising assigning a unique Universal Resource Identifier (URI) to the standard metadata schema, registering the standard metadata schema in a Resource Description Framework (RDF) triple store, registering the standard metadata schema in a system topic map, and registering the standard metadata schema in a repository index; generating a polyhierarchical metadata description of an artifact, using at least two of the standard metadata schemas, wherein the polyhierarchical metadata description of the artifact comprises at least two Points of View (POV) of the artifact, each of the at least two POVs including a metadata description of the artifact using a different standard metadata schema among the plurality of standard metadata schemas, and the POV including the URI of the standard metadata schema; assigning a URI to each of the at least two POVs; encapsulating, as a digital object (DO), a datastream, the at least two POVs, the URI of each of the two POVs, and the URI of the standard metadata scheme used for the POV's metadata description, and including in the DO a URI, the URI being unique to the DO, wherein the datastream is a digital surrogate of the artifact; cataloging the DO and registering the DO; ingesting a description of the cataloging and the registering of the DO into a digital preservation repository for long term preservation; harvesting and ingesting a surrogate copy of the DO into a digital repository for digital asset management and aggregation; upon ingesting the surrogate copy of the DO, registering the DO in the repository resource index, wherein registering the DO in the repository resource index includes registering each metadata description in the DO, the URI of metadata description, and the URI of the DO in a RDF triple store as RDF, and on a topic map; aggregating the surrogate copy of the DO with another resource, and encapsulating a result of the aggregating as a complex digital object (CDO); registering the CDO in the digital repository for digital asset management and aggregation; filtering metadata and datastreams of the CDO; and disseminating a result of filtering metadata and datastreams of the CDO to a distribution channel.