Australian pre colonial farming.

Right, I work in soil science, and one of the guys at work had bit of a startling theory that makes a lot of sense. Its known that for the most part Indigenous australians didnt engage in the sort of agricultural practices typical for agrarian societies. And for the not-most exception part theres controversy around it.

So I was chatting with the guys at work about this wondering why that was, and it was put that maybe there was but indigenous australians discovered it was a bad idea.

To put it simply, australian soils are terrible. And over time farmed land here tends to degrade, and get saline and desert-y. Is it plausible that at some point in history there where aboriginal australians running farms in some of the areas that are now considered "desert" and this might have contributed to the loss of green land, before they realised that hey, this might not be a good idea and restricted themselves to the hunter gathering and mobile agriculture that we more commonly associate with aboriginal people.

Has there been any evidence for this?