Poland's Communist Party, which had kept a low profile since the imposition of martial law, moved to reassert its public authority yesterday as its official newspaper called for a swift purge of membership that it said should show "no leniency" and would be "difficult and perhaps painful."

The party committee of the Warsaw province, meeting with Army officers and military commissars as "invited guests," expressed the "necessity to exploit martial law to clean up the party's internal affairs."

The Warsaw provincial party organization is regarded as one of the most conservative in the country and its meeting this week could set the tone for a meeting of the full party leadership expected to take place next week, the first since martial law was declared Dec. 13.

Meanwhile several prominent Polish cultural figures and intellectuals have addressed an appeal to the martial law chief, Gen. Wojciech Jaruzelski, warning of possible tragedy and further bloodshed unless martial law is lifted, according to information arriving from Poland.

While a purge of the Polish party's ranks has been mentioned frequently in the official press and radio, yesterday's articles and commentaries gave the broadest indication of their likely scope, in language that gave little indication of concessions by the leadership.

The steps by the Communist Party to reassert its traditional role came as the martial law government presented a detailed report on the nearly four weeks of military rule and announced that telephone service will be restored--but subject to censorship--in all of the country's 49 provincial capitals for the first time since Dec. 13.

The Interior and Communications Ministries said the restoration was possible because of "further improvement in social discipline and the observance of martial law regulations."

"At the same time," the announcement warned, the martial law censorship authorities "are entitled to control and interrupt telephone conversations" to prevent their use for antistate activities.

The complete blackout of private telephone and telex service was a key factor in the initial effectiveness of martial law, leaving the independent trade union Solidarity and its supporters unable to coordinate opposition.

Deputy Premier Boguslaw Stachura, in a report yesterday to the parliamentary commission responsible for administration of justice, gave the most detailed official account so far of arrests, crimes and casualties under martial law.

Stachura, who is responsible for internal security, said, according to Radio Warsaw, that 5,906 people have been detained under martial law and that 839 were freed, leaving 5,067 in detention. So far, he said, 170 of those interned have been tried and convicted by military courts.

Stachura said nine strikers or protesters had been killed in clashes with security forces or died later of injuries, and he said that in the first few days of martial law, "strike action or attempts at organizing strike action were noted at 199 enterprises and establishments" throughout the country.

All of the figures are considerably lower than estimates by Solidarity sources in Poland, which put the number of detentions at 15,000 or more. Severe travel and communications restrictions, however, make it impossible for independent observers to compile figures.

Stachura said it now appears that "part of the nation has accepted the introduction of the state of martial law with approval and the decisive majority has accepted it with understanding, although the orders and bans . . . are being received as a considerable hardship."

The Warsaw provincial party's committee's call for a purge came in a report by its secretary, Jerzy Boleslawski, at a meeting yesterday.

His report, according to Warsaw television, "stressed that the conviction prevails in the Warsaw Communist Party committee of the necessity to exploit martial law to clean up the party's internal affairs. There should not be any place in the party for onlookers, for passive people or for those who have broken the Leninist norms."

"Those people who do not feel their strength is up to meeting party statutory and ethical duties are leaving the party ranks," Boleslawski said.

Warsaw television said later, according to Agence France-Presse, that Tadeusz Fiszbach, who had been closely identified with Solidarity, had resigned as head of the Gdansk party committee.

Trybuna Ludu, in an article headed "Need for Consolidation," called yesterday for "the purging of party ranks from people with alien ideological and political convictions" and for "allowing those who entered the party by accident and have never felt themselves Communists to leave the party peacefully."

It warned that the purge "is going to be difficult and perhaps painful" and said, "This is why the process should be not only swift but also principled and just, without harming anybody but showing no leniency as well."

The following is based on information arriving from Poland:

The party's talk of a purge may be designed to cover up a huge drop in membership from thousands of protest resignations. One Polish journalist said "baskets" of party cards were being turned in at factories. One well-placed party source said that in the Warsaw region alone, about 4,000 members had resigned since martial law was declared. He estimated that as few as one-sixth of the region's 178,000 party members are still active.

The appeal addressed to Jaruzelski by prominent Polish figures said that "the introduction of martial law was aimed at depriving society of its voice and subjugating the nation to military dictatorship."

It called for freedom for internees, guarantees of full civil rights, abolition of summary court proceedings and nullification of verdicts already handed down by such courts, a stop to mass firing for union activity and cessation of official demands that Poles sign loyalty oaths.

The original signatories were: Wanda Wilkomirska, a leading violinist; the Rev. Jan Zieja, Dr. Jozef Rybicki and Dr. Stanislaw Broniewski, all World War II heroes; Marian Brandys, a writer; Dr. Zofia Kuratowska, a physician; Daniel Olbrychski, a leading actor; and Prof. Stefan Kieniewicz, a historian.

Universities, meanwhile, reopened to seniors.

At Warsaw University, the faculty met Thursday and were told that military authorities had made four demands as a condition for resumption of studies. They were bans on political meetings or demonstrations, on political activities by students and faculty except for official party activities, on leaflets and other printed propaganda and on graffiti.

A faculty source said the university rector, Henryk Samsonowicz, accepted the conditions but laid down three of his own. He refused to subject his faculty and students to "ideological verification," the official term for purging; he said powers of the university senate should remain unchanged and he stated that the university would not refrain from demanding the release of detainees.

The source said negotiations on the demands were under way and agreement was likely.