<Environment Root> - A World in Which We Live
An <Environment Root> represents the data provider’s ‘world’ or ‘playbox’. In a transmittal representing the physical components of a chess game, the chessboard would be an <Environment Root>.
Multiple <Environment Roots> are permitted in for a single transmittal, in case the ‘world’ is specified in more than one spatial reference frame (SRF), e.g. multiple UTM zones.