 Despite the small amount of scientific instruments they carried, most of the range support boats in the PLAN also shoulder the responsibility of inshore surveying, regardless of their limitations.Originally, the majority of the hydrographic surveys had been conducted by civilian fishing vessels which had additional scientific equipment, naval and governmental crews on board.However, since the Chinese economic reform, and the depletion of the fishery resources, the civilian fishing vessels must venture much further out into open ocean on extended voyages, thus were no longer available for coastal or inland water survey operations.