Cheryl,

I reject the idea that it is inevitable or essential that Aus grow to over 30 million for its own benefit or survival. There can really only be one obvious reason for accelerated long-term Aus population growth, and that is national security - as world overpopulation and concomitant increasing scarcity of essential resources approach breaking point, and nations increasingly covet resources and opportunities beyond their national boundaries. But, security lies in diplomacy and high-tech defence, and not in huge armies.

Admittedly we have a current shortage of skilled labour in the mining sector (and apparently in the health sector), and this may only be assuaged by overseas recruitment - and our welfare system has generated a growing class of Aussies unwilling to take ordinary or menial jobs, also creating a demand for imported labour. However, the mining boom is finite, and those menial or messy job vacancies will continue to be limited - unless we start chasing our tails, and if only some of those debutantes would get off their backsides.

As industrial technology moves increasingly towards mechanisation and robotics there will be increasing emphasis in two essential classes - professional/engineering/technical/research/development and skilled/semi-skilled - with a diminishing ratio of menial, plus the inevitable unwilling.

Working smarter, rather than harder, is the order of the day, and of the 21st Century, and that has to include moving progressively towards productive full employment. The best future for Aus will be to achieve the elevation of all - to eliminate any underclass or disadvantaged, and afford dignity. Such an objective should concurrently be applied to all of humanity's disadvantaged, and this can only be possible with a finite ceiling to population over the whole of the planet.

No envisaged technical advance can afford genuine quality of life to all current billions, let alone cater for any increase. Aus can certainly accommodate more than our 23.5 million, but the world desperately needs reform and reigning-in.

Part of the food debate is energy. Crops grown for fuel are a very large part of the food security/shortage problem. Moreover, fuel produced from former food crops, produces a net energy loss that must be made good from other sources, like the grid.
I see that as simply dumb and prefer very low water use, algae production, which needs neither arable land or energy inputs, to produce endlessly sustainable comparatively inexpensive alternative fuel.
After that, reticulated energy needs to be a carbon free peak demand alternative.
My preference is thorium, which is four times more abundant than uranium. It is quite often accompanied by rare earths, which make mining it doubly profitable.
Unlike uranium oxide, thorium leaves the ground as virtually pure material needing very little separation/preparation to make it suitable as a power source.
Liquefied in fluorine, lithium and beryllium salts, it is mostly consumed in the reaction process, with the heat transferred to the steam turbines, by helium.
It is old 50's technology, abandoned because there was no weapons spin-off.
20/20 hindsight would infer we should have adopted it, if only to prevent the disastrous melt downs, and or waste disposal issues, associated with oxide reactors?
The very small amount of waste produced in the thorium reaction, is far less toxic and eminently suitable for very long life space batteries.
All these factors combined, possibly make Thorium reaction the cheapest most affordable, currently available, peak demand, carbon free energy in the world?
Which likely explains why India, which a still has a very large, very poor demographic, have adopted it; or, why the "greens", relentlessly bag it?
Simply because it incorporates the term nuclear? Or, might enable us to re-industrialise, with energy dependant high tech manufacture? Rhrosty.

Cheryl,

"We will have a population in Australia of about 34 million people by 2050 although it might fall to 32 million. None of this matters. In Australia we have a surplus of food and energy."

Well of course that sounds fantastic. Never mind that most of the 32 or 34 million people in Australia will probably consume meat, whether beef, lamb, pork, chicken or any other industrial meat food.

Think for a minute, beef in this country consumes at the very least, 5-7 kilograms of grain and approximately 15 litres of water to produce, of which we export (nett loss of water and grain) to other modern, affluent countries. The same can be said of all other meat products coming from this grain production declining nation and a country that is rapidly depleting or polluting its natural, potable water supply.

Population, no matter how you argue the fact, is the major reason our poor planet is in over-shoot, oh dear, gosh, I have now put myself into that doom and gloom myopic camp that just does not see a way forward.

Unfortunately Cheryl you have the 'rose coloured' glasses on. Population and our industrial agriculture is one of the primary reasons we are headed toward a food famine globally. Australia may produce some great food, export our current excess, but consider the energy required, the pollution produced, the loss of our critically short supply of good top-soil, introduction of bio-accumulating genetic modification of plants, trees, shrubs, animals etc as we feed them increasing amounts of anti-biotics, steroids, and god knows what else to keep industrial agriculture growing!

You can keep your 32 or 34 million people future, I prefer mine with sustainable, permaculture type organic food, grown in balance with nature and one that treats the earth with respect.

Not that you would care, based on your continuing stance on a perpetual growing population.

I meant to say "Think for a minute, for every kilogram of beef produced in this country, the cow consumes at the very least, 5-7 kilograms of grain and approximately 15 litres of water to produce that kilo of "beef", of which we export (nett loss of water and grain) to other modern, affluent countries. The same can be said of all other meat products coming from this grain production declining nation and a country that is rapidly depleting or polluting its natural, potable water supply.

Geoff