A new report suggests a surge in Australian mining production will offset some of the negative economic effects of declining investment in the sector.The Mining in Australia report released by economic forecaster BIS Shrapnel expects mining production to soar by 41 per cent in the next five years. The report says mining activity as a share of Australia's GDP will rise from 18.7 per cent to almost 20 per cent.Adrian Hart, BIS Shrapnel's head of infrastructure and mining, says despite growing concerns about how Australia will cope without the resources investment and construction boom, mining will continue to drive economic growth. "The growth in the mining part of the Australian economy is being driven by production from here," he said. "So the strong growth that we see in production is going to boost the share of mining, in terms of the share of the Australian economy. "It's going to more than outweigh the detraction caused by a weaker construction and investment profile."More output, fewer jobsAt the same time, mining investment is expected to fall by 20 per cent and lead to mixed results for workers in the resources sector."If you're in the construction industry, it's tough," Mr Hart said."We're forecasting a 40 per cent fall in buildings and structures activity over the next five years in mining."But on the other hand, if you're involved on the production, operations, maintenance, facilities management - all of these areas are going to go ahead quite strongly through the next five years."Mr Hart says overall employment in the sector will suffer as a result of mining production becoming more reliant on machinery.Meanwhile, accounting firm PricewaterhouseCoopers says volatile commodity prices and higher costs have hit the bottom line of the 50 medium-sized mining companies on the Australian stock exchange. PwC head of mining Jock O'Callaghan says some of the medium-sized miners have become takeover targets."I don't think we are going to find that there are less companies around, but I certainly think there is, within certain sectors, the possibility of greater consolidation," he said. "Gold is one where we might find, over the next short while, [ownership] becomes a little bit more concentrated."