The leader of Poland's Roman Catholic Church appealed to the nation for a 30-day moratorium on strikes today in a clear bid to defuse a possible confrontation between communist authorities and the independent trade union federation Solidarity.

The plea by Archbishop Jozef Glemp, the Polish primate, for "peace and work without tensions" came as the two sides appeared to be heading toward a collision on several key issues.

The Polish church frequently has intervened in government-union disputes during the past year, calling for labor restraint last December, but it had not previously called for a moratorium.

Glemp's call came after Solidarity threatened to shut down all daily newspapers for six days if it does not gain editorial control over television coverage of its first congress, due to open next week.

The union's confrontation on the issue of information and the course of economic reforms was described in a union communique as perhaps "the most difficult battle since August of 1980," when workers wrested the right to their union.

The strike by printers in Olsztyn is in its eighth day despite calls to return to work. While Solidarity organized a spectacular two-day strike that left Poland virtually without daily newspapers, the Olsztyn printers decided to continue their strike over local grievances.

In Radom, local Solidarity leaders have called for an indefinite strike at a major metalurgical plant employing 12,000 workers unless the government agrees by Friday to start negotiations on an issue dealing with the 1976 food riots in that city. The workers are demanding that the government rehabilitate those victimized in the riots and punish security officials involved in their suppression. All factors in the Radom area have scheduled one-hour warning strikes on Friday.

The government issued a statement today asserting that "the political climate in the country has worsened" and blaming "irresponsible actions taken by certain Solidarity chapters" for it. Solidarity retorted that the government was pursuing policies designed to create a confrontation.