MOSCOW, DEC. 31 -- As the new year approaches, the mood in the Soviet Union is more somber than merry: on Jan. 1, perestroika begins in earnest and people are getting nervous.

Until now, the promise of economic reform in this hypercentralized state has been often spoken but barely felt. In 1988 it will take effect where it really counts: on the shop floors and in the directors' offices of factories, farms and enterprises.

Friday, 60 percent of Soviet industrial and agricultural production switches to a system known as khozrachiot, or economic accountability, a concept that has no equivalent in the West. It means that enterprises are on their own -- linked to the national economy by plan guidelines, but given autonomy to settle their own bills, keep their profits and, to some extent, find their own customers and suppliers.

In an economy beset by chronic shortages, this kind of independence does not suit everyone. In recent weeks, Soviet newspapers have been filling up with articles and interviews that reveal the anxieties of those working on the ground level of the economic system. "Will there be enough money for wages?" queried one headline in the daily Socialist Industry.

In a roundtable discussion published this week in the government newspaper Izvestia, directors of Moscow enterprises that already are working under the new system poured out their woes.

The head of a textile factory told how he went out into the wholesale market to look for raw materials and came up 20 percent short. "Under khozrachiot, it is going to be tough," said Fyodor Plekhanov. "We even calculated our future losses from the lack of raw materials: our profits will be down by 1 million rubles" -- about $1.5 million.

Nikolai Seledtsov, a brigade leader in a bus factory, described how his crew was penalized because a factory in Kalinin did not fulfill its share of work in time. "We worked normally, so why should we pay out of our own pockets for the miscalculations of others?" he asked.

At a production group that makes scales and other measuring equipment, director Yuri Sergeinko found himself short 400 tons of sheet metal. "On a country-wide scale, that's small change," he said. "But for us, it is extremely alarming. What are we to do? I do not rule out that in February one of our factories will have to stop work."

Soviet leader Mikhail Gorbachev noted in November that with the coming economic reforms, perestroika -- or restructuring -- is moving into its second stage. In the newspapers and on the streets, among intellectuals, ordinary workers and economists, this next stage is being universally proclaimed as the most difficult, requiring major psychological adjustments and offering harsh lessons in economic reality with few immediate results.

"Miracles, especially economic ones, do not happen all at once," said Izvestia. "It requires very complicated work and we have to be ready."

Other aspects of Gorbachev's reform package will be taking hold in the coming year: new laws are due to further define the role of cooperatives and widen the sphere of private services and even small-scale manufacturing. Joint ventures with foreign firms are expected to increase; reforms are coming in banking and, gradually, in pricing.

But the first centerpiece of reform thus far is the new law on state enterprises that goes into effect Friday. The Soviet Union's top economist, Abel Aganbegyan, described it as a compromise "worked out as a result of a clash of opinion and contradictory judgments." Some economists say that "self-financing" cannot be made to work until prices are reformed since it forces managers to seek profits based on unrealistic costs.

Debates continue over key elements of the law but Friday the experimenting stops and the reforms begin. Aganbegyan, answering a critic on a recent television talk show, noted that no matter how much theory a child may know, it cannot learn to swim until it gets into the water.

Last year, 160 enterprises in Moscow were working under khozrachiot, as part of a scattered experiment. Now, as the first major law on economic reform takes effect, another 300 enterprises in the city switch to the new system. By 1989, all of Moscow's industry is to be "self-financing" under the reform.

To put the need for change in context, Izvestia listed the problems plaguing the city's industry: the loss of 50 million rubles ($80 million at the official exchange rate) in defective goods, 360 million from unrealized technology, 12 million in fines for unjustified warehousing of supplies and 60 million in fines for unfulfilled contracts.

Thus far, results of self-financing under the initial experimental conditions are mixed, according to figures recently cited by Stepan Sitiryan, deputy chairman of the state central planning agency Gosplan. Overall, enterprises working under khozrachiot performed better than ones working under the old system, recording higher productivity and profits, he said in the Communist Party newspaper Pravda on Monday.

However, in Moscow, one-sixth of the self-financing factories were unable to deliver on their contracts, which cost them a total of 30 million rubles in fines.

These coming years, before the start of the 13th five-year plan in 1991, are transitional ones. Although the new law calls for "full economic accountability" for enterprises, that is still a long way off. The transition is being softened by a new economic lever being introduced into the Soviet lexicon: state orders.

Next year, state orders are expected to dictate between 80 and 90 percent of industrial output, leaving only 10 to 20 percent to be negotiated freely in contracts between factories and enterprises. The proportions vary, with some heavy industries 100 percent reliant on state orders, and consumer goods closer to 70 percent. By the end of the transitional period, or 199l, the mix of state orders is expected to be between 30 and 40 percent.

This development is a hot point of debate in the press and among experts. Some argue that the government contract is just another name for the old-style dictatorship of the central planning agencies. Others say that without this transitional measure assuring the flow of essential goods into the economy, chaos would prevail.

Either way, state orders are popular with factory directors because they carry with them guarantees for deliveries of materials and resources. Initially, the state order will also provide the mechanism to rescue enterprises operating at a loss -- now estimated at 13 percent of Soviet industry.

"We are going to pull them out of it by economic methods, . . . not the way we used to where we gave them everything, they ate it and gave nothing back to society," explained Arkady Nagavitsin, a senior economist at the Institute for Economy. In the initial transitional period, state orders will be regulated to keep losing enterprises afloat, Nagavitsin said. Purchase prices will be adjusted, and credit offered at one-half of one percent, he said.

"We will give them a chance," he said. "How they will use that chance I cannot say."

If all else fails, the new law provides bankruptcy procedures for Soviet enterprises and factories. However leading Soviet economists have predicted there will be few bankruptcies because of the political sensitivity of closures. Likewise, unemployment has been ruled out as a consequence of the reforms, although experts predict gradual large-scale dislocation of jobs and workers.

Some experts are concerned that the state orders will continue to isolate the economy from the consumer, making factories produce goods for which there may be no demand and pushing production toward goals measured in quantity, not quality.

The sensitive issue of quality control will continue to be regulated by a growing bureaucracy.

According to the economic reform plan adopted by the Communist Party at a Central Committee meeting last June, the role of government contracts will diminish to between 30 and 40 percent by 1991. Then virtually everything but the military and social services sectors will be provided by wholesale trade between enterprises.

By that time, long-promised reforms in the Soviet Union's archaic and clumsy price system also will be in place. Many economists here predict that until prices are allowed to reflect cost, reforms will be only marginal, and possibly even doomed to failure because of the system's contradictions.

The sensitive issue of quality control will continue to be regulated by a state inspection agency empowered to reject products for shoddy workmanship and force the factory to absorb the costs. The agency is widely seen as one reason for slowed economic growth this year and, in some instances, for creating conflicts within factories.