UPDATE 2-About one third of South African truckers end strike

* Three smaller unions agree to return to work

* Biggest transport union under pressure to follow

* Fuel, consumer good, cash deliveries disrupted

(Adds Gold One, Chamber of Mines, edits throughout)

By Agnieszka Flak and Wendell Roelf

JOHANNESBURG, Oct 9 (Reuters) - About a third of strikingSouth African truckers have agreed to return to work onWednesday, easing pressure on Africa's biggest economy where twoweeks of labour unrest in the transport sector have hit suppliesof fuel, cash and consumer goods.

But disputes in the mining sector escalated after Gold One

fired the majority of its 1,900 workers at itsEzulwini operation, paralysed since last week by a wildcatstrike. Atlatsa Resources said it had also fired 2,161miners for an illegal strike.

Tuesday's decision by three small transport unions with15,000 members to abandon the truckers strike puts pressure onthe biggest labour group, the South African Transport and AlliedWorkers Union (SATAWU), which represents about 28,000 workers,to reach a deal and suspend its calls to widen the strike.

Since August, almost 100,000 workers across South Africa,including 75,000 in the mining sector, have downed tools inoften illegal and violent strikes that may hit economic growththis year and undermine investor confidence in the minerals hub.

"The three unions advised that they came to this decision inlight of the fact that employers have now offered double digits(a pay rise) for the year," an employers association said. Itwas still in talks with all groups to hammer out a final deal.

The rand , which fell to 3-1/2 year lows against thedollar on Monday on worsening investor sentiment about labourstrife, firmed to 8.735 immediately after the news of the threeunions saying they will end their walk-out.

SATAWU is demanding annual wage increases of 12 percent fortwo years - more than double the inflation rate, while employershave offered a total 18 percent pay rise over that period.

"We are willing to compromise on our demands, but only aslong as the employers do the same," said Vincent Masoga, aspokesman for SATAWU. Talks with employers were held on Tuesday.

An employers body said last week that the freight industrywas losing around 1.2 billion rand ($135 million) in turnovereach week. If the protests expand to rail and ports, exports ofcoal and other minerals would also be hit.

Affected companies include logistics groups Imperial Holding, Super Group , Grindrod , Barloworld

and Bidvest . MINING UNREST

President Jacob Zuma's ruling African National Congress hasbeen criticised for letting the strikes spread. Moody's ratingsagency downgraded government bonds a notch last month, sayingineffectual governance posed long-term economic risk.

Large parts of the mining sector, responsible for about 6percent of gross domestic product, have been brought to astandstill in the last two months by wildcat strikes by morethan 15 percent of its workforce.

Platinum miner Lonmin reached a deal inSeptember to end a deadly wildcat strike for a yearly wageincrease as high as 22 percent for some miners.

Within hours of the deal, workers at nearby platinum minescalled for similar raises. In the days that followed, wildcatstrikes hit sectors including gold, iron and car manufacturing.

Last week, mining giant Anglo American Platinumfired 12,000 of its workers who went on an illegal strike,raising the stakes in the labour disputes. Analysts are warningof further job losses and the closure of marginal shafts.

Almost 50 people have been killed in the current labourstrife - 34 of them by shot dead by police on Aug. 16 atLonmin's Marikana mine in the deadliest security incident sincethe end of apartheid in 1994.

"The ongoing violence that has led to the senseless anduntimely death of workers will further discourage directinvestment in the industry where investors were already hesitantabout the mining industry in South Africa," Bheki Sibiya, thechief executive of the Chamber of Mines, said in a statement.

Kumba Iron Ore said it could not honour itscontractual obligations to deliver ore to ArcelorMittal's SouthAfrican unit due to an illegal protest at its giantSishen mine.

On Monday, a local government workers' union said it alsoplanned a protest in the next few days, the first sign of labourunrest spreading into the public sector.($1 = 8.8828 South African rand)

(Additional reporting by Xola Potelwa and Sherilee Lakmidas;Editing by Jon Herskovitz and Andrew Osborn)

((agnieszka.flak@thomsonreuters.com)(+27 11 775 3154)(ReutersMessaging: agnieszka.flak.thomsonreuters.com@reuters.net))