Deteriorating economic conditions have forced Poland's Communist authorities to embrace the politically risky challenges of holding down living standards and wages this year while tightening discipline over long-demoralized workers, government officials and economists here say.

Economic stabilization has emerged as the first priority for the leadership of Gen. Wojciech Jaruzelski, which sees gradual improvements in consumption and production as the key to consolidating the tenuous control it has gained over the country. Yet a variety of economic barriers, ranging from severe energy shortages to heavy foreign debt payments, have combined to curtail growth during the past year and threaten a prolonged period of stagnation.

As a result, Poles are beginning a new year with the prospect of only slight improvements in living standards that are still far inferior to those they knew before the tumultuous era of the Solidarity trade union movement. In addition, government officials have signaled that they no longer can afford the high wage increases and subsidies to consumption they have allowed to avoid social unrest in the past.

Many economists and diplomats here consequently predict that Jaruzelski's government will be tested in the coming months as it seeks to impose discipline on workers already dissatisfied with their material conditions. A failure to control grass-roots demands, these experts say, could recreate shortages slowly overcome in the past several years or touch off a new economic crisis.

Already, the government's economic plans and a wave of recent price increases have drawn criticism even from officially sanctioned labor leaders. "In our view, the plan represents a philosophy of impotence," said Alfred Miodowicz, the chairman of the All-Poland Trades Union Alliance, at a recent plenum of the ruling Polish United Workers Party. "The Polish worker will not learn from it how his life may improve [or] why it is necessary to tighten his belt."

Other groups both in and outside the government are concerned that preoccupation with short-term difficulties has stifled the program of economic reforms introduced by Jaruzelski in 1983. "The reform has lost its impetus and is now dying down halfway -- or even a quarter of the way -- toward its goal," wrote Jerzy Surdykowski in the Catholic weekly Tygodnik Powszechny.

Aware of the political dangers of stagnation, government officials say they have curtailed needed investments in order to offer a slight improvement in consumption of food and consumer goods this year. But even official plans project a considerable slowdown in the rate of economic recovery from the level of the past three years. Growth in the national income is estimated at only 3 percent, compared with an average of 5.8 percent in 1983-84 and growth for 1985 estimated at 3.5 percent.

Even these marginal gains may be erased by shortages of coal and other fuels to power industry and supply heat during a winter expected to be long and cold. "Coal reserves are shrinking alarmingly, and power consumption in peak hours is close to power stations' maximum capacity. Most fuel stores in rural areas are empty," the government daily Rzeczpospolita reported last month. Without stringent conservation measures, it added, the country risked "disturbances in industrial production and in the health service and schools."

The energy shortage, economists here say, is one of the clearest examples of how Poland's slow economic recovery under Jaruzelski's leadership has been stalled by deep-rooted economic ailments that have tended to worsen rather than improve.

Following the drastic drop in production and living standards that accompanied the Solidarity era in 1980-81, recovery has been based largely on easily stimulated sectors such as mining and agriculture, where stable working conditions, high prices and good weather led to rapid improvements.

As industry has approached the levels of output it reached in the late 1970s, however, aging machines, energy shortages and inefficient management of supplies have both prevented further growth and lowered the quality of Polish goods. Polish industrial exports to the West have declined sharply, making it impossible for authorities to meet payments on debts to western banks and governments or to import new machines.

With $2.1 billion in payments due this year on Poland's $29 billion foreign debt, authorities say they now face the same dilemma as many debt-burdened developing countries: unless exports are increased dramatically, Poland will not be able to meet its debt payments, much less import the new machines and raw materials it needs for industry. Yet Poland's ability to compete abroad is declining because of that very shortage of funds to pay for imported goods.

"There will be a necessity to keep rescheduling the debt," said Bazyli Samojlik, a top government economic strategist. "And since the real situation does not change, slowly the resources of our country [to pay the debt] will be used up."

While the debt payment problems have complicated Poland's attempts to improve relations with the United States and other western governments, the most serious political problems may arise from the government's failures in eliminating shortages and other distortions from the domestic marketplace, experts here say.

Even as the growth in goods production has slowed during the past year, wages have risen much more rapidly than prices as government authorities have given in to pressure from industrial workers.

"The government has not been strong enough to hold down wages," said Leszek Balcerowicz, an economist who is critical of the government. "Its first priority is to keep people quiet. And you keep people quiet by giving in to wage demands by big, strong groups."

Now, however, government officials say they no longer can allow higher-than-planned wage increases without risking severe shortages of goods. If industrial production is crimped by energy shortages or other problems, they note, the choices may be stark: rejecting workers' pay demands at the risk of industrial unrest, or admitting a return to the bare shop shelves and long lines that were a symbol of Poland's economic crisis in the early 1980s.

The confluence of internal and external problems, officials concede, means that even while focusing his attention on the economy, Jaruzelski's most important tasks will remain political: convincing restless workers to accept the need for price increases and more efficient work, and winning the credits Poland needs from wary western governments.

Even if both goals can be achieved, most economists outside the government are skeptical about the prospects for economic gains in the coming years. "The most likely outcome is long-term stagnation with slowly accumulating problems, such as debt," said Balcerowicz. "I can't see radical changes under this government, and radical changes are necessary to alter the basic situation."