Bottom trawling, or dragging nets along the ocean floor to catch fish, is so devastating to the marine environment that the practice should be banned from fragile areas, according to a U.S. National Academy of Sciences report released yesterday. The report, which was requested by the National Marine Fisheries Service, recommended protecting areas along the Pacific Coast, the North Atlantic, the Gulf Coast, and the Alaskan coast, reducing trawling elsewhere, and requiring modifications to equipment to minimize damage. The recommendations were welcomed by environmentalists, some of whom compare bottom trawling to clear-cutting. A bipartisan group of Congress members plans to introduce legislation today to restrict bottom trawling.