* President's popularity falls 5 points to 40 percent
* Social conflicts plague Humala's first year in office
Peruvian President Ollanta Humala's approval rating fell to a fresh low in July, a year since he took office as concern grows over his handling of increasingly violent social conflicts, an opinion poll showed on Sunday.
Humala's popularity fell 5 percentage points for a second consecutive month to 40 percent, while the number of respondents who said they disapproved of his administration rose to 51 percent, according to the Ipso Apollo survey.
Peru is a leading global metals supplier, but the push to develop its mineral riches has triggered dozens of conflicts due to fears over potential environmental damage and opposition from local residents who want a bigger share of the windfall.
Deadly violence in protests against Newmont $5 billion Conga mine prompted calls for Humala to reshuffle his Cabinet earlier this month.
Opponents of the Newmont mine say it would cause pollution, hurt water supplies and fail to generate enough local economic benefits. Humala has backed the project as a generator of thousands of jobs and enormous tax revenues.
"The Congo conflict is the biggest single factor in explaining the deterioration in Humala's image," said Alfredo Toreros, director of Ipso Apollo.
"The difficultly for the government lies in the fact that there's no broad consensus on how to resolve it," he added.
Humala took office on July 28 last year on pledges to include the 30 percent of Peruvians living in poverty in a decade-long economic boom, but mediating the conflicts has become his biggest challenge.
Toreros said, however, that Humala's predecessors had seen their approval ratings fall even lower at a similar stage of their presidential terms.
One year into his five-year term, former President Alan Garcia had an approval rating of 32 percent while Alejandro Toledo had just 18 percent.
Humala's approval rating was 45 percent in June and 50 percent in May, according to Ipso Apollo.
Sunday's opinion survey, which was published in the El Comerci newspaper, polled 1,210 people from July 11-13. It has a margin of error of 2.8 percentage points.