Australia should consider diversifying its economy beyond the mining sector, suggests a new report.

Although mining will still be a major economic driver for Australia over the next 20 years, new opportunities for export-led growth will be generated from different sectors, says the report from economic forecaster Deloitte.

The report, "Positioning for Prosperity? Catching the Next Wave," released Monday by Deloitte Australia, identified agribusiness, gas, tourism, international education and wealth management as the next "super growth waves" for the country. It is the third in Deloitte's series of reports, "Building the Lucky Country, Business Imperatives for a Prosperous Australia," which began in 2011 with a focus on the country's skill shortage.

By tapping into these five growth sectors, Deloitte says, the country could add about $236 billion to its national economy in the next 20 years.

While federal and state governments would play a supportive role to promote growth, ultimately it is up to business leaders to take the lead in positioning Australia as a competitive global force in the five proposed growth sectors, the report says.

"It's all about catching the next wave," said Deloitte Access Economics partner Chris Richardson, co-author of the report, in a statement. "Mining will continue as a major driver of our prosperity. But that boom is slowing and our competitive advantage is being challenged. We need another wave -- or several -- to create more diversified growth," he said.

Australia was the world's biggest coal exporter by volume until it was overtaken by Indonesia last year.

"We assumed the mining boom was going to be permanent, but rising costs and falling productivity are crippling our global competitiveness," Richardson said.

Yet Australia's Bureau of Resources and Energy Economics is forecasting a surge in Australia's mining exports.

The bureau predicts export revenues from Australia's resource sector will increase about 60 percent over the next five years, growing at an annual rate of 7 percent to total $284 billion in 2017, Mining Australia magazine reported Tuesday.

The Deloitte report notes the rapid industrialization that characterized the past decade in Asia has taken a considerable toll on air quality in Asia's cities and "has propelled Western Australian gas to the top of the global 'most wanted' list."

"Our gas is a clean and green alternative to coal that points to major development potential for this state in coming decades," Mike McNulty, Western Australian Managing Partner of Deloitte, said in a statement.