Johannesburg — When martial law was imposed in Poland last month, world gold markets gave a collective yawn.
But in South Africa, financial analysts fidgeted uncomfortably. Major world disruptions no longer automatically kicked up the price of their bullion, it seemed.
It was one more signal that gold prices cannot be counted on to carry this nation, the world's largest producer of gold, into another boom year after two years of exceptional growth, say many analysts here.
As a result, South Africa is preparing for a year of ''consolidation,'' as many analysts here are calling it. That means the economy will be hard pressed to afford many of the ''reforms'' the government has committed itself to on the economic front. The reforms include improved housing, education, and social services for blacks - expenditures that would bring blacks closer to the standards enjoyed by whites.
''Money is a major instrument of reform'' in South Africa, points out Harry Schwarz, chief economic spokesman for the opposition Progressive Federal Party. ''We need 6 percent growth to make a real inroads'' toward greater economic equality among the races, he says.
By contrast, economic forecasters here look for growth between zero and 2.5 percent (adjusted for inflation) for South Africa in 1982. The economy grew by more than 4 percent last year, it is estimated, and 8 percent in 1980.
South Africa's minister of finance, Owen Horwood, recently warned South Africans they were entering a period in which it would be necessary to ''tighten belts.'' A leading South African financial magazine has labeled 1982 and 1983 the ''difficult years.''
For blacks, the difficulty will be gaining ground in terms of jobs and wages in a sluggish economy. Although the wage gap between whites and blacks has narrowed noticeably since 1973, whites on average still earned more than four times as much as blacks in 1980.
For all South Africans, the slow-moving economy of 1982 will be exacerbated by persistently high inflation. Consumer prices are forecast to rise between 10 and 15 percent this year.
A high rate of inflation is viewed as an inevitable trade-off for increasing economic equality among races in South Africa. Wages must rise faster than productivity increases in order to close the black-white earnings gap, which is seen as a minimum requirement for maintaining social stability without any significant political reforms.
The nation's treasury will clearly feel the pinch this year. A slower growing economy will reduce revenues. Lower gold prices will have particularly strong effect on government income. In the fiscal year ended last February, the South African government earned 25 percent of its total income from taxes and lease rights on gold mines.
Gold revenue now probably makes up less than 15 percent of government revenues, according to one estimate. And the contribution could worsen in 1982, if recent gold prices are any indication. On Jan. 18 the price of gold was fixed in London at $369 per ounce, its lowest level since 1979.
Analysts here believe the price of gold, which soared to over $800 per ounce in 1980, is remaining low partly because of a high level of gold sales by the Soviet Union, the world's second-largest gold producer. A large investment firm here estimates Soviet gold sales last year totaled 220 tons, compared to 90 tons the year before.
The high level of gold sales is believed to be necessary for the Soviet Union to finance grain imports, its presence in Afghanistan, and its economic assistance to Poland.
Other common explanations among gold analysts for the relatively low price are the continued strength of the US dollar against other currencies and renewed expectations among some that interest rates in the United States may turn up soon.
A strong US dollar hurts gold because investors often seek refuge in gold when the dollar is seen as weakening or unstable. High interest rates are viewed as competition for gold in that they make alternative investments more attractive for their rate of return.
It is a measure of the underlying strength of the South African economy that a real growth rate of up to 2.5 percent is viewed negatively. Most developed countries of the world would consider that a relatively strong performance.
''The ship is sound,'' pronounces Richard Lurie, president of the Johannesburg Stock Exchange. Indeed, despite slumping gold prices, Mr. Lurie says the general assumption among major investors is that ''South Africa's basic financial condition is better than that of any other time in history.''
Investor confidence is clearly strong. The Johannesburg stock market, measured by its industrial index, outperformed most other major world stock markets in 1981.
The Johannesburg index rose more than 17 percent last year, compared to a 14 percent decline on Wall Street. West Germany's stock index fell over 4 percent, and the French market sank 17 percent.