A main premise of the following guest post from Boxer* is that across the West Australian wheatbelt, water tables are showing an upward trend. Boxer explains the problem and the need to act now if we are to learn from history and avoid the problems that destroyed, for example, agriculture in the valleys of the once fertile Tigris and Euphrates Rivers.
I have asked Boxer for a link to some data that quantifies the extent of the rising water table problem. He has responded that:
There is no single place that I can find where a large amount of water table data is assembled in one place. This is not because there is a paucity of data, but I think because there is so much data, and the fundamental cause and effect of dryland salinity has been so well established for so long, that the publications over the last decade or two do not directly present water table data. The scientific debate has moved on.
If a problem is complex and widespread, all the more reason, in my opinion, to have a few agreed indicators and regularly report on how they are trending. Others may see things differently? The issue is important. Let’s have some discussion. Here’s the post:
Like a number of other people who comment on this blog, I enjoyed Jennifer’s recent piece on Ockham’s Razor (ABC Radio, http://www.abc.net.au/rn/science/ockham/stories/s1509193.htm ) in which she addressed the arguments of various doomsday prophets such as Tim Flannery and Ian Lowe.
The Prophets of Doom have a list of iconic issues. I think it is healthy for the Prophets to be challenged because they have a vested interest in, for example, arguing that climate change will be the end of all things, just as coal miners have a vested interest in business as usual. Challenge them both.
On the issue of salinity however, I argue that dryland salinity is a major issue for this country. On this one, I am with the doomsday crowd. My vested interest? My professional life is bound up in finding ways for agriculture to adapt to rising water tables and perhaps even find ways to prevent the problem becoming as bad as the models predict.
Jennifer uses the example of the Murray River, where, at a point just upstream from the off-take for Adelaide’s water supply, salinity levels have fallen over the last couple of decades due to salt diversion work. Good news, but is that a reasonable reflection of the state of affairs in the whole river system? I don