Sunday, 14 September 2008

There should be no controversy about ending irrigation and revegetating

News I received yesterday on an Age poster in Swanston Street of talk that there would be protests over a north/south water pipeline from the Goulburn to Melbourne frustrates me still further.

If we think on these logical lines:

— if current increases in carbon dioxide have cut runoff into Melbourne’s dams by 75 percent, there is virtual certainty that projected greenhouse gas increases will cut them to zero soon

— that desalination is extremely greenhouse-intensive and will make the problem worse besides creating demand for water due to higher temperatures

— then we logically come to the conclusion that all non-essential water usage in southern Australia must be phased out as rapidly as possible.

The major non-essential water usage in Australia, though people do not realise its non-essential nature, is of course irrigation Australia is known among economists for having very low farm subsidies, but among ecologists for its extremely low yields due to extremely ancient soils even with irrigation. Irrigation uses over two-thirds of Australia’s water, so that if it were completely phased out, Australia’s urban population could theoretically get by with a third as much runoff (this of course is an overestimate because most irrigation water cannot be diverted to a major city and there would be ecological costs doing so).

However, what water could be diverted to cities might be very valuable to cope with the declining supply global warming will inevitably produce in southern Australia.

The ecological and, globally, social benefits of a really serious plan to covert all irrigation land in the Murray-Darling Basin back to native flora would also be immense. Not only would Australia’s land benefit from having plants truly adapted to its unique soil conditions, but nations in Europe and East Asia whose sole natural resource is fertile soils would not have that resource rendered worthless by Australia’s ecologically destructive agriculture. Rather we would have farming on pedologically suitable land on what Kirkpatrick Sale calls a “human scale”.

No comments: