Johannesburg — South Africa's black press has suffered another blow, threatening to reduce the open expression of black views in this country to near inaudibility. The major Afrikaans publishing house Nationale Pers has gobbled up three black-oriented publications.
One of the purchases is politically insignificant. But the other two - Drum Magazine and City Press, a Sunday newspaper - will bring two antigovernment publications into the fold of a decidedly pro-government publishing company.
None of the publications is black owned, but all three are aimed at black audiences. Indeed, there are no major black-owned newspapers or news magazines in South Africa.
The purchases represent a general consolidation of the South African press into the hands of four publishing conglomerates - two English, two Afrikaans, and all controlled by whites.
The trend is seen by analysts as particularly worrisome for this racially divided society, where whites are exposed to an almost exclusively white point of view that deals only superficially with the issue of the day: black demands for political rights.
As the major publishing houses consolidate power, maverick voices of political dissent are being forced into oblivion. And the concentration of press power in fewer hands may make even more remote any possibility for a truly black press - owned, managed, and written by blacks - to emerge.
The three publications have been assured by their new owners that they will continue to enjoy journalistic freedom. But David Bleazard, president of the South African Society of Journalists, says he is still worried. Mr. Bleazard decried the move, which ''will further restrict the already limited diversity of viewpoints'' available in the South African press. And noting the ''political sympathies'' of Nasionale Pers, which owns the government mouthpiece in the Cape Province, he said there was danger the ''independent and challenging voice of City Press will be muted if not muffled altogether.''
An independent black-owned press flourished in the early 1900s, spearheaded by a small group of black journalists educated at Christian missions. But in the 1930s whites began to buy up the fledgling black publications, both to capitalize on what was seen as a lucrative new market and to soften the increasingly radical tone of the black press. The independent black press came to an end. It has never recovered.
Both Drum and City Press were founded by James Bailey, a wealthy white. He started Drum in 1951, apparently for its commercial potential in attracting black readers with a formula of ''sex, crime, and sport.'' Drum was not an early success. But it later became a respected voice of black township life, publishing a number of exposes on labor conditions, prisons, and crime.
City Press was founded last year by Bailey. Like Drum, it is aimed at a black audience and is written primarily by blacks. Both publications are critical of the government, although Drum in recent years has adopted a slicker, more apolitical tone.
Journalism is a risky venture for anyone, white or black, in South Africa. There are more than 100 laws restricting what may be published. Numerous editors have been brought to court for alleged violations.
But while white journalists have often been targets of harassment and intimidation, the government has moved more decisively over the years to silence the black voice.
Between 1974 and 1981, some 73 black journalists were detained, 15 of them subsequently banned. That represented almost one-third of the total number of black journalists employed at that time.
In the government crackdown on black political dissent that followed the black riots in 1976, the World and the Weekend World newspapers - white owned but aimed at blacks - were banned. The Post newspaper then opened, but it was forced to close in 1980.
The interesting feature of the banning of the World is that it was no more, and possibly even less, outspoken than some of the English-language press. Some analysts have concluded the banning was more a government reaction to black dissent and political vigor in general than to anything the World said in its columns.
The Sowetan is the only existing daily newspaper directed at a black readership. It is white owned and is criticized by some black community leaders in Soweto as being far too moderate and parochial. It has a circulation of close to 100,000.
Many analysts conclude South Africa's ruling whites simply will not permit a forthright black press. ''If you are going to be an honest black newspaper, you are going to be shut down,'' said a black journalist quoted in a recent academic study of the black press.
There are financial constraints as well. Analysts say the political and financial risks of launching a black newspaper or magazine make investors shy away.
Blacks constitute the fastest-growing reading audience in South Africa, although they still represent only about 34 percent of all daily newspaper readers. There is also the relatively new choice of black television. But it is government controlled and divided by language group.