* Nickel touches 100-day average, points to more selling -Triland
* Speculators trim net long copper position for 2nd week -CFTC
* Coming Up: U.S. ISM-New York index July at 1345 GMT
(Adds official midday prices, details)
LONDON, Aug 4 (Reuters) - Copper was steady on Monday as investors were mindful of growing global supplies, even as a rally in China's stock markets indicated improving prospects for demand.
Chinese shares closed at their highest in 7-1/2 months after a China Securities Regulatory Commission spokesman said on Friday that improving economic performance, more liquidity and market reforms were sparking a rebound in equities.
Also China's powerful economic planning agency said earlier Beijing would increase investment in areas including the property sector, while authorities would advance wide-ranging economic reforms such as changing the fiscal and pricing systems.
China consumes around 40 percent of the world's copper.
Copper investors were reluctant to bid up the metal, however, given expectations for increased supply in the latter part of this year.
Freeport-McMoRan Inc's Indonesian unit will resume copper concentrate exports by Wednesday, the local chief executive said on Monday, after it resolved a six-month tax dispute with the government.
"The likes of zinc and nickel have their own bullish supply-side story, but copper doesn't really. I think copper is in surplus ... (though) it's relatively small," said Stephen Briggs, an analyst at BNP Paribas.
"We've got another roughly 12 months of this kind of fundamental weakness, where copper could go down as far as $6,000 a tonne, but no more than that," he added.
Three-month copper on the London Metal Exchange traded at $7,093 a tonne in official midday rings, was up 0.26 percent on the day, after closing down nearly 1 percent last week.
Other metals such as LME zinc, lead and aluminum, which have constrained supply, rose on the London Metal Exchange.
Limiting losses in copper, U.S. job growth slowed a bit in July and the unemployment rate unexpectedly rose, pointing to slack in the labor market, which could give the Federal Reserve room to keep interest rates low for a while.
Also, manufacturing activity in China and most of Asia gathered pace in July, while expansion slowed in Europe but remained healthy in the United States.
Still, hedge funds and money managers cut their bullish bets on copper futures and options in the week to July 29, the Commodity Futures Trading Commission said on Friday.
There is widespread risk aversion in global markets on account of political tensions, with the euro zone's sentiment index slumping unexpectedly in August as EU sanctions on Russia weighed on growth expectations.
"If risk aversion remains high, it is likely to preclude any rise in prices for the time being, especially as net long positions continue to be relatively high, which means there is further potential for them to be reduced," Commerzbank said in a note.
Chinese trade data for July will be released on Friday, and copper imports may be low again as trade houses find it difficult to get finance to store metal after suspected fraud at China's Qingdao port earlier this year.
In other metals, broker Triland said LME nickel's chart picture was deteriorating, with a close on Friday below support at $18,500 a tonne and after it hit its 100-day moving average for the first time since a bull trend began earlier this year.
"It is a clear sign that nickel is unlikely to resume that uptrend in the near future and is indeed more likely to come under further selling pressure next week," it said in a note on Friday.
Nickel inventories are hitting record highs as hidden stocks leave China following a fraud probe at Qingdao's port, showing supplies are plentiful despite a halt to shipments from top exporter Indonesia.
Nickel was last bid up 0.38 percent in rings at $18,475 a tonne, while tin was last bid down 0.33 percent in rings at $22,400 a tonne.
Aluminum traded up 1.42 percent in rings at $2,003 a tonne, zinc was last bid up 0.90 percent at $2,359 a tonne while lead traded up 1.40 percent at $2,251 a tonne.
Three month LME copper
Most active ShFE copper
Three month LME aluminum
Most active ShFE aluminum
Three month LME zinc
Most active ShFE zinc
Three month LME lead
Most active ShFE lead
Three month LME nickel
Three month LME tin
($1 = 6.1790 Chinese Yuan)
(Additional reporting by Melanie Burton; editing by Jason Neely)