Reuters: Environmental activists tried to shut down Australia’s second-largest aluminium smelter on Tuesday in a widening series of protests targeting the resources sector, blamed by green groups for dragging its feet over global warming. Production at the giant Tomago smelter north of Sydney was unaffected by the protest by environmental group Rising Tide, said a spokeswoman for the smelter, which is 51.55 percent owned by Rio Tinto Ltd/Plc (RIO.AX) (RIO.L). Three members of the …