An underwater graveyard becomes the birthplace of a biological wonder

Around 600 miles northeast of New Guinea there's a 49-square-mile archipelago of almost-forgotten islands called Truk which played a very important role in 20 th-century American history.

In 1944 Truk, a forward supply depot for the Japanese Navy, was attacked by American warplanes and, in a two-day period 500 tons of bombs were dropped, 265 Japanese planes were destroyed, and 60 Japanese vessels were sunk. The bottom of the 40-mile-diameter Truk lagoon became a graveyard of metal corpses, an eerie new underwater landscape.

Now, 40 years later, nature has resurrected Truk lagoon and it boasts one of the earth's most amazing man-made coral reefs. The rusted underwater vessels and the nearby mangrove swamps have become nurseries and breeding grounds for a whole new ecosystem, including sponges, octopi, shrimp, oysters, sharks, fiddler crabs, and man. The Truk lagoon, part of a US protectorate, has been declared a ''historic site,'' protected by government edict.

Wolfgang Bayer, a world-renowned natural history cinematographer, was assigned by television's innovative natural-history series, ''Nature,'' to take his cameras to Truk to record the remarkable rebirth, or rather total renewal, of this environment: Resurrection at Truk Lagoon (Sunday, March 25, 8-9 p.m., check local listings for repeats).

Cinematographer Bayer, with the aid (above and below the surface) of Dr. Sylvia Earle, a California Academy of Science researcher, has managed to collect a series of joyous film clips that celebrate life underwater as well as life in the swampland and in the Truk towns. A major revelation to viewers is the significant irony of the new ecosystem: that the new coral reef could not have been formed naturally in that sandy lagoon but through war and destruction, a more congenial atmosphere for living creatures was created.

Says host and executive producer George Page: ''The sea, as always, has the final word.''

''Truk'' is glorious proof of the triumph of nature over mankind's destructiveness.