At the Tomb of the Unknown Soldier in Warsaw's Victory Square, a wreath-laying ceremony today honoring Poland's National Day drew a sparse crowd and little of the fanfare one might have expected on a day marking also the lifting of martial law.

"It's just a formal thing," said a young woman on the square, shrugging off as most others interviewed did the practical impact of the abolition of military rule announced yesterday. "The same people are in power as before."

Lech Walesa, leader of the banned Salidarity trade union movement, dismissed the lifting of martial law as a propaganda ploy that will do little to solve Poland's pressing social and economic problems, the Los Angeles Times reported. "It is all just make-believe and fiction," he said Friday in his apartment in Gdansk.

Most affected by the Communist leadership's gesture are many of the 800 people under investigation or sentenced for political offenses who will be freed under the terms of a limited amnesty.

Their friends and families waited anxiously today to see just who will be released during the next 30 days. The wife of one prominent detainee said she had been given strong indications by security police that she and her husband would be allowed to leave Poland if they decided to go. Troublesome dissidents have often been encouraged to leave for the West in the past.

Symbolically, at least, Polish authorities have turned the page on a chapter of history here that ended in disillusionment--and in some instances still, imprisonment--for activists associated with what was Eastern Europe's first independent union, Solidarity. But the struggle--for free expression, for independent political and social structures, for a working economy--goes on, although in different forms than before martial law.

By and large, military rule pushed resistance efforts underground. They assume the form now of clandestine meetings, of Catholic Church-sponsored discussion groups, of a flourishing underground press and of whispered conversations in cafes and parks.

But if the opposition's tactics have been forced to change, so have those of the authorities. The use of open force is much less evident. Under martial law, Poland's Communist leadership has amended penal codes and labor legislation to exercise tighter, but more subtle, control over society, closing legal gaps officials discovered were there when they went to thwart Solidarity.

The special legal regulations passed by parliament yesterday and taking effect with the abolition of martial law outline like a road map the areas still troublesome for the government. The economy is clearly a primary concern.

The new restrictions go against the decentralizing efforts of recent economic reforms, opting instead for more central controls over pricing and production decisions and curbing the prerogatives of the fledgling workers' self-management councils, which are the key to any significant reform of factory management.

Also signaled by the regulations are plans for an ideological offensive against Polish intellectuals and university students--two groups that were particularly restive under martial law.

"Their intentions are very clear," said a Warsaw professor, a former Communist Party member unfriendly toward the current government. "The next group of intellectuals to be punished are teachers. It's the last group not to be covered so far."

As disturbing for many Poles as the new regulations are, two factors prompt a degree of optimism among some people here. One is that the new rules may not be heavily enforced and were enacted rather to satisfy nervous officials or to appease the Kremlin.

"Like everything in Poland, on paper the regulations look tough but in practice they may be softer," said a Polish journalist aligned with the opposition. "There were already enough laws to put everyone in jail if the government really wanted to."

A second encouraging development noted by some is the role the Roman Catholic Church was able to play this week in shaping the special regulations bill. Lobbying hard behind the scenes, senior church officials proved extremely effective in forcing out the harshest permanent changes in laws sought by the government and in gaining more flexible language in the provisional rules that were passed.

One potentially significant amendment to the final bill that was asked for by Catholic officials will allow the Council of Ministers to cancel administrative decisions issued under martial law. It is this provision that Janusz Zablocki, head of a Catholic parliamentary club, invoked yesterday when he appealed to authorities to issue a resolution that would return to work and schools those fired or expelled for political reasons.

All in all, the main significance of ending martial law seems not to be domestic but international. Polish officials expect a rollback of at least some Western economic sanctions imposed after martial law was declared Dec. 13, 1981.

At the same time, authorities here have insisted that neither pressure from the United States nor from the Catholic Church played a part in the decision to lift military rule. The decision, they say, was dependent solely on the judgment that life in Poland has returned as near to normal as it will get for some time.

In any case, political protests, arrests and tensions can be expected to continue, further frustrating authorities and complicating U.S.-Polish relations.