http://www.ebay.com/itm/10-5-Sumida-Gawa-Style-Antique-Japanese-Art-Pottery-Vase-w-High-Relief-DRAGON-/321218529820?hash=item4aca1dca1c:g:CqMAAMXQigBSMjdc

Best I can find from my research is that this plate is from a studio potter,,fairly modern,, and is a sumida style as far as how it was made !! Sumida or sumidagawa pottery is a high relief pottery using many different figures from Japanese folklore !! Some of the more modern studio potters have used this method of applying figures to heavy earthenware !! These are made as art pieces and not for a specific use !! Your mark is likely the personal mark of the potter !! The vase above is made in a similar technique !!

http://www.antique-shop.com/forums/index.php?topic=19220.0

Here is the link to the other forum !! I believe that is your plate Mat linked to !!