Amtrak President Paul Reistrup will not be reappointed as chief executive of the troubled rail passenger corporation after falling to reach agreement with his board of directors on a new one-year term.

The breakdown in negotiations was revealed at a board meeting of the government-subsidized company yesterday.

In a separate development, the rail-road industry reported yesterday that its freight-hauling business last year resulted in the lowest levelof profitability since the Depression.

Reistrup, who has been Amtrak's president for three years, will remain on the job until his current term expires June 30. he said yesterday he also would remain for a while after July 1 to help his successor through a transition period.

Amtrak's board yesterday appointed a five-member committee to begin the search for a new chief executive.

Milwaukee Road Chairman William Quinn will head the executive search team, but committee members may not have to spend much time looking. According to government sources, Department of Transportation Secretary Brock Adams has asked Alan Boyd to consider the post.

Boyd, himself a former DOT Secretary, Civil Aeronautics Board chairman and president of the Illinois Central Gulf Railroad, most recently served as President Carter's special representative for U.S. British aviation negotiations last year, with the rank of ambassador.

Boyd reportedly was traveling on the West Coast yesterday and was not available for comment.

Reistrup's departure from Amtrak is based on his unhappiness with conflicting pressures from Congress and the Carter administration that have created a financial crisis for the passenger service.

He sought from the board - and apparently failed to win - an agreement on future policies. Given federal celings on subsidies for Amtrak, the corporation must make major cutbacks in services later this year. DOT is preparing a study on what routes should be maintained.

Reistrup has argued that the government either should provide adequate to operate and improve passenger train services in the public interest or abandon the attempt to revive train travel altogether outside key metropolitan corridors.

The Amtrak chief also was seeking an increase in his $85,000 annual salary but has said that was "not a major" issue. Yesterday, he told United Press International: "After a while it just becomes impossible."

Amtrak's board also delayed a decision yesterday on whether it should assume operations of Southern Railways's Southern Crescent between Union Station and New Orleans until the DOT report on future ruotes is published May 1.

Washington-based Southern has asked the Interstate Commerce Commission for approval to abandon the train, citing monthly losses of $560,o00. The ICC will hold bearings on the proposal later this year, Southern will keep running the train at least until August.

The railroad industry, meanwhile, yesterday reported operating profits of $347 million in 1977, down from $442 million in 1976 and the lowest level since 1932.

According to the Association of American Railroads, an industry trade group, the rate of return on investments for railroads dipped to 1.13 percent from 1.53 percent in 1976.

Industry revenues rose to $20.1 billion from $18.6 billion in 1976 and expenses rose to $16.4 billion from $15 billion.

AAR President William Dempsey said the industry's rate of profits is expected to decline further in the current quarter because of the coal strike and extreme winter weather.

In a petition to be filed with the ICC in May, the railroads will seek to start charging the higher lates in July. Current negotiations with rail labor unions could lead to additional rate hikes later in the year.