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For all crops, therefore, using a recharge‐area assessment and a 3rd order of magnitude relationship between recharge and extraction, water rather than soil is the factor limiting crop production.
A more precautionary approach would use a 4th order of magnitude multiplier (1/10,000th of the study area) and determine that groundwater could support 12,000 ha of irrigated agriculture (ignoring other uses). Under this assumption, the availability of water would pose a far greater limit to crop production than the availability of suitable soil. And that doesn’t take into account competition for groundwater from other uses.
Using the prospectivity method, we estimate that the area of potentially groundwater‐irrigable land in northern Australia to be around 40,000‐60,000 ha. This constitutes around 0.4% of northern Australia’s potentially class 1+2 annual cropping soils, and approximately 1%, 2%, 0.2% and 0.4% of the class 1+2 soils for perennial crops, rice, forestry and improved pasture, respectively.
Crop production in northern Australia is limited by water, not soil.
The current total surface water storage capacity in northern Australia is ca 11,170 GL (Figure 12, Cresswell et al., this report). If we exclude the Ord River Dam, which is already accounted for in irrigated agriculture (and for which there are limited opportunities for similar storages in the north), the volume drops to ca 1,170. Assuming that all this water was available for agriculture (and it isn’t – much is lost via evaporation and is used for other purposes, such as domestic supply), it could support ca 80,000 – 120,000 ha of irrigated agriculture. As outlined above, this is sufficient to irrigate only a very small proportion of the potentially suitable agricultural soils. Irrigated agriculture in the north is likely to be water rather than soil limited.
I may not get up north, but I do read what others have found and studied up there.
If you're such a firm believer then
* How many hectares do you see being able to grow crops?
* How much would this increase current crop production for Australia?
I just notice in you post, it does seem to contradict your post earlier of the day, that poor soil was the main problem.
Also seems to support my argument, that it is a lack of reliable water, that is the problem.
Also if you believe the climate experts, the north is going to get wetter and the south is going to get dryer. But that wouldn't fit with the argument would it.lol
Also lol, where you say you may not get up north but you read.
It seems you read between your first post at 1.10 and second at 4.20