The widespread use of RDF-based information necessitates efficient information retrieval techniques in wide-area networks. In this paper, we present Dynamic Semantic Space, a schema-based peer-to-peer overlay network that facilitates efficient lookup for RDF-based information in dynamic environments. Peers in this overlay are grouped based on the semantics of their data which are extracted according to a set of schemas, and self-organized as a semantic overlay network. To reduce overheads incurred by peer joining, leaving and content changes in a high-dimensional overlay network, peers are constructed as a one-dimensional semantic space that facilitates efficient routing for both pull and push requests. A search or a subscription request is only routed to the appropriate cluster that holds related data, thus reducing unnecessary search cost and increasing the efficiency of locating information. Through a comprehensive simulation study, we demonstrate the effectiveness of our proposed...