You’d know this, Moth, but city people might not be aware of just how much water is needed for agriculture. The water content of an apple is probably about 80%. Think of any other fruit or vegetable or animal. Whether the water comes from irrigation (it’s mostly drip irrigation in horticulture (maybe all these days?) or from rainfall – it has to be made available to grow food. (Of course, most Australian agricultural land is dryland agriculture, not irrigated. It still needs water.)
If we only produced food, feed and seed for domestic consumption we’d need a lot less water. But if we stopped exports we’d gut the agricultural sector – because most production goes overseas. If we gutted the agricultural sector we’d gut the country – no towns between major cities any more. No more land and waterway management capability. No more local food processing industries. And so on.
The pragmatic approach is to keep finding ways to be more efficient with water use, whether it be for agriculture, mining, manufacture or household consumption. In the long term we won’t survive as a nation if we drain our rivers dry. But that doesn’t mean we can’t use any water at all from rivers. It does mean that we have to learn to keep to a water ‘budget’.
Thinking out loud and very simplistically, I guess that budget could be summed as: rainfall – evaporation – human use + water returned to the waterways (after use) + water from other sources (eg desal plants). And the budget would apply over a period (long enough to cater for droughts and floods and water storage to tide between the two). That will probably mean cutting out more of the irrigated farming in the medium term and reverting more of it to dryland production – or at least shifting it to regions where there is higher rainfall (eg from the Murray Darling system to northern Australia, maybe).
My guess is that the pattern of production will be quite different in 50 years to what it is today, particularly with changing climates. Hope we can manage the change without too much damage.
Great points Sou! Another point on the apple – there is also a lot more water used to keep the tree alive to grow the fruit. Transpiration accounts for a lot of water loss (sorry I don’t have the numbers on me). I know that more than 90% of water rained on Australia never returns to the ocean via river mouths…
On the MDB plan, I wrote a fairly personal on that in The Human Island, chapter, ‘Nothing is Wasted’.
Being from Adelaide, with my field experient, I’m very motivated about water management. I’ll get a great photo today when I head out north, which is at complete contrast to the rice crop I s napped a photo of in the same region.
Sorry for the brief reply, I must dash for a long day…
Typical nonsese. The author doesn’t reference well at all, expecting the reader to take their word for it and when they do reference, it’s to a site with an obvious biased agenda..
No matter what these people say, there is clear, undeniable evidence that where fluoridation of drinking water occurs, there is less dental caries. So when they have an something as provocative as “fluoride shows no benefits” you can tell they’re fishing.
What these characters ought to do is spend more time exploring the potential detrimental effects of fluoridation (when applied by WHO guide lines), submitted within the science peer reviewed literature.
Of course they won’t, because it doesn’t support their position. I started looking at the many studies Merilyn provided me, but I grew bored. So many had tiny study groups or found differences that couldn’t be repeated or was within the margin of error.
They just need it to mbe true and so turn off any critical capacity they may of once had.
newanthropocene.wordpress.com 
Here’s the ABS water use figures for agriculture:
http://www.abs.gov.au/ausstats/abs@.nsf/0/CEC913CEB73C81BCCA25788C0018000D?opendocument
You’d know this, Moth, but city people might not be aware of just how much water is needed for agriculture. The water content of an apple is probably about 80%. Think of any other fruit or vegetable or animal. Whether the water comes from irrigation (it’s mostly drip irrigation in horticulture (maybe all these days?) or from rainfall – it has to be made available to grow food. (Of course, most Australian agricultural land is dryland agriculture, not irrigated. It still needs water.)
If we only produced food, feed and seed for domestic consumption we’d need a lot less water. But if we stopped exports we’d gut the agricultural sector – because most production goes overseas. If we gutted the agricultural sector we’d gut the country – no towns between major cities any more. No more land and waterway management capability. No more local food processing industries. And so on.
The pragmatic approach is to keep finding ways to be more efficient with water use, whether it be for agriculture, mining, manufacture or household consumption. In the long term we won’t survive as a nation if we drain our rivers dry. But that doesn’t mean we can’t use any water at all from rivers. It does mean that we have to learn to keep to a water ‘budget’.
Thinking out loud and very simplistically, I guess that budget could be summed as: rainfall – evaporation – human use + water returned to the waterways (after use) + water from other sources (eg desal plants). And the budget would apply over a period (long enough to cater for droughts and floods and water storage to tide between the two). That will probably mean cutting out more of the irrigated farming in the medium term and reverting more of it to dryland production – or at least shifting it to regions where there is higher rainfall (eg from the Murray Darling system to northern Australia, maybe).
My guess is that the pattern of production will be quite different in 50 years to what it is today, particularly with changing climates. Hope we can manage the change without too much damage.
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Great points Sou! Another point on the apple – there is also a lot more water used to keep the tree alive to grow the fruit. Transpiration accounts for a lot of water loss (sorry I don’t have the numbers on me). I know that more than 90% of water rained on Australia never returns to the ocean via river mouths…
On the MDB plan, I wrote a fairly personal on that in The Human Island, chapter, ‘Nothing is Wasted’.
Being from Adelaide, with my field experient, I’m very motivated about water management. I’ll get a great photo today when I head out north, which is at complete contrast to the rice crop I s napped a photo of in the same region.
Sorry for the brief reply, I must dash for a long day…
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Not to forget this thought-provoking little piece:
http://theconversation.edu.au/is-the-murray-darling-basin-plan-enlightened-ask-voltaire-11468
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Hi Moth
Have you seen this?
http://articles.mercola.com/sites/articles/archive/2012/01/03/fluoride-show-no-benefits.aspx?np=true
Mike
Mike Williamson
Follow me at http://www.mike-williamson.blogspot.com.au
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Typical nonsese. The author doesn’t reference well at all, expecting the reader to take their word for it and when they do reference, it’s to a site with an obvious biased agenda..
No matter what these people say, there is clear, undeniable evidence that where fluoridation of drinking water occurs, there is less dental caries. So when they have an something as provocative as “fluoride shows no benefits” you can tell they’re fishing.
What these characters ought to do is spend more time exploring the potential detrimental effects of fluoridation (when applied by WHO guide lines), submitted within the science peer reviewed literature.
Of course they won’t, because it doesn’t support their position. I started looking at the many studies Merilyn provided me, but I grew bored. So many had tiny study groups or found differences that couldn’t be repeated or was within the margin of error.
They just need it to mbe true and so turn off any critical capacity they may of once had.
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