Polish authorities are considering reorganizing the country's trade union movement by breaking up the territorial structure that gave political strength to the independent union Solidarity.

Under the plan being discussed, union groups would be required to form along individual industrial and professional lines, much as Poland's trade unions were organized before the rise of Solidarity 1 1/2 years ago.

Solidarity's organizers chose a structure of regional groups, coordinated by a national commission, because this arrangement mirrored the government and the Communist Party apparatus. In this way, it was thought, the new union would be well-positioned to press its demands--a concept that proved itself in practice.

Tentative plans for barring regional groupings were confirmed today by Poland's government spokesman, Jerzy Urban, in an interview. He said no final decision has been made.

Courts, meanwhile, sentenced 101 persons charged with minor offenses in the rioting in Gdansk Saturday to jail terms ranging from one to three months, the official Polish news agency PAP said. Leaders of the demonstrations, to be tried later, are expected to receive heavier sentences.

In Katowice, a military court imposed prison sentences of from three to seven years for nine leaders of a coal miners' strike called in December to protest martial law. The government also decided not to reopen universities yet, saying it could not "safeguard the peace of the campuses," The Associated Press reported.

Since the imposition of martial law Dec. 13, Solidarity has been suspended, and many of its national and local leaders are being held in internment centers around the country. Western analysts expect it will be some time before Polish authorities permit resumption of trade union activity in any form. Most likely, a strengthening of local and factory Communist Party groups will come first so they can serve as controls on eventual worker organizations.

Urban said it can be expected that the authorities will announce a set of "political conditions" that Polish trade unions will have to abide by. Following this announcement--for which no date was given--Urban said there would be a "public discussion" about the precise form the new unions should take.

He said the government did not intend to provide any detailed blueprint for the unions. Rather, he said, the labor movement would be allowed to recreate itself within the general bounds that will be set down.

These bounds, Urban said, will require the trade unions to honor the country's laws and constitution and prohibit their organizing as a political movement.

Discussing Solidarity, Urban made clear that he thought that by assuming a territorial structure, the union had readied itself to play a political role.

"I'm almost sure that one of the legal demands will be for trade unions to have a structure that is proper for all trade unions in the world," he said.

"The territorial structure of Solidarity was a clear sign of its political interests. What interests, for instance, do a shoemaker and a pilot have in common? Sharing a territory doesn't mean they have common interests. Solidarity may have this or that structure, but Solidarity as a political structure will not exist."

Urban said officials in the government's bureau of trade union affairs have been sounding out some union activists about the future of the movement. Except for Solidarity's interned chairman, Lech Walesa, he would not name them.

Urban said these contacts with Walesa could not be characterized as formal talks. He said Stanislaw Ciosek, the minister responsible for trade union affairs, visits Walesa "every now and then" and conducts "simply conversations" with the union leader about Solidarity's past and Walesa's view of the future.

On other questions, Urban said:

No formal church-state negotiations are taking place. Roman Catholic Church officials have been saying in private to government authorities the same things they have said publicly about the conditions in Poland, he said.

The church, Urban said, has pressed for improvements in some internment centers and for release, for family or health reasons, of some of those interned. Whenever possible, Urban said, authorities have tried to meet these requests.

Authorities have given no formal orders for harassment or roughing up of any inmates in the internment camps. But Urban said it was impossible for any government spokesman to account for individual police or guard actions in every case.

In a separate action today, Polish authorities formally protested a Washington Post story Wednesday that said some inmates had been beaten at a detention center in the town of Suwalki. The government denied that any such incident had occurred.

There is no grand timetable for the eventual lifting of martial law. Urban said the authorities here are constantly analyzing actions and moods around the country to determine whether to relax or tighten restrictions.