Australian Megafauna: Impacts on Soils

Ayrton

Ad Honorem
Jan 2017
4,264
Bendigo
I am hoping someone here has a particular interest in the Australian megafauna. I have next to no knowledge of the subject (far closer to ‘no’ than ‘next’, lol). I am keen to know especially if the Australian continent ever had migratory herds and what impact they had on soils they may have had.

[I realise this may be an area where evidence on the ground (no pun intended) may be thin to say the least. So I am interested to hear anything about megafauna and other species (insects etc.) and their impact on their environment, even if it broadens discussions on this thread. Any discussion on this - to me - little known area of pre-history would be appreciated!]
 
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sparky

Ad Honorem
Jan 2017
5,008
Sydney
.
there was no herd animals in the original fauna , lots of various kangaroos ,including giants ,
the diprotodons seemed to be made of small groups at the most .
when there is large herds , piles of carcasses happen at dangerous locations , there isn't any discovered


it could be because Australia is not a very fertile environment ,food density is low so fauna density is low also

another possible explanation is that there were no marsupial ungulates
 

Ayrton

Ad Honorem
Jan 2017
4,264
Bendigo
.
there was no herd animals in the original fauna , lots of various kangaroos ,including giants ,
the diprotodons seemed to be made of small groups at the most .
when there is large herds , piles of carcasses happen at dangerous locations , there isn't any discovered


it could be because Australia is not a very fertile environment ,food density is low so fauna density is low also

another possible explanation is that there were no marsupial ungulates

Thank you.

I fear that we did not have large groups of ungulates. It is herds that work in symbiosis with grasslands (mixed herbage may be more accurate). Though what came first, the chicken or the egg, or the bovine or the pasture, is a moot point. But where there are migrating herds there are deep stable soils (generally speaking).

I guess the point for me is, if no herds, then why don’t we have more forest climax communities? Australia not being a ‘very fertile’ environment I find curious. We have vast deserts and vast drylands, but why? Fauna works with flora to create forests (as a very broad and general rule), otherwise mixed herbage ‘grasslands’ are created; enough trees to grow into forests can’t grow because of regular munching by herds.

I can’t see climate alone as being the cause of Australian continental ‘infertility’. Add fertilizer and water and we produce crops. (Add more humus to the soil and get better water infiltration and storage of same, and healthier crops: you can start with primary material (dirt?) and still create fertility. Bovine herds help a hell of a lot).



I wonder why we never had herds, or coast to coast forests in lieu of herds?
 
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sparky

Ad Honorem
Jan 2017
5,008
Sydney
.
Soil is caused by plants absorbing carbon and integrating it in the sub strata
it require a certain amount of water to protect it from natural oxidation ,
I guess the soil forming conditions were just not there

the presence of eucalyptus would have been an impediment , they poison the soil for other flora




After the Human colonization , widespread burning did expand the grasslands but impoverished the soil

of course that would not explain the lack of large herds , I have a hunch the the lack of ruminants animals with their sophisticated digestive system is the key ,



This is an interesting question and deserve to be looked into at some length

I will do some search to get a better answers
 

specul8

Ad Honorem
Oct 2016
3,385
Australia
Thank you.

I fear that we did not have large groups of ungulates. It is herds that work in symbiosis with grasslands (mixed herbage may be more accurate). Though what came first, the chicken or the egg, or the bovine or the pasture, is a moot point. But where there are migrating herds there are deep stable soils (generally speaking).

I guess the point for me is, if no herds, then why don’t we have more forest climax communities? Australia not being a ‘very fertile’ environment I find curious. We have vast deserts and vast drylands, but why? Fauna works with flora to create forests (as a very broad and general rule), otherwise mixed herbage ‘grasslands’ are created; enough trees to grow into forests can’t grow because of regular munching by herds.

I can’t see climate alone as being the cause of Australian continental ‘infertility’. Add fertilizer and water and we produce crops. (Add more humus to the soil and get better water infiltration and storage of same, and healthier crops: you can start with primary material (dirt?) and still create fertility. Bovine herds help a hell of a lot).



I wonder why we never had herds, or coast to coast forests in lieu of herds?
just a note to let you know I am not ignoring this ; I just spent over 40 mins making a huge post on the subject with ref links pics and diagrams ...

Then my whole range of sites on the bar (hence all my refs and sites I found ) and the long post I was writing , just seemed to vanish and took me to a new screen ?

On the other forum I use, when you come back and click on reply post, any exited work that wasnt posted is auto saved and pops back up again ... not here

:sad:

I cant do all that again at the moment .
 

Ayrton

Ad Honorem
Jan 2017
4,264
Bendigo
.
Soil is caused by plants absorbing carbon and integrating it in the sub strata
it require a certain amount of water to protect it from natural oxidation ,
I guess the soil forming conditions were just not there

the presence of eucalyptus would have been an impediment , they poison the soil for other flora




After the Human colonization , widespread burning did expand the grasslands but impoverished the soil

of course that would not explain the lack of large herds , I have a hunch the the lack of ruminants animals with their sophisticated digestive system is the key ,



This is an interesting question and deserve to be looked into at some length

I will do some search to get a better answers
Thanks Sparky. Much appreciated.

For the record: there was widespread burning pre-European arrival too. Interesting footnote to know if Europeans burnt in the saw way as Aboriginals did.
 

specul8

Ad Honorem
Oct 2016
3,385
Australia
Thanks Sparky. Much appreciated.

For the record: there was widespread burning pre-European arrival too. Interesting footnote to know if Europeans burnt in the saw way as Aboriginals did.
I doubt it as now we are only just acknowledging their techniques and are asking them to show us . We train them in what we know and they train us in what they know :)




Ten Aboriginal Land Management Team members from the Hunter recently received TAFE certificates after completing basic firefighting training with the Rural Fire Service. This was followed by an Indigenous fire management workshop led by Indigenous fire practitioner Victor Steffensen. During the event Victor conducted a traditional burn.

 

specul8

Ad Honorem
Oct 2016
3,385
Australia
We have to remember there are large areas in Australia that are fertile. A whole swath in NSW, where a huge amount of our produce comes from ( there is abattle on as they want to use this land for CSG - crazy .

Another example is the Dorrigo plateau in coastal central east coast. It probably had mega fauna and was burnt but it has high fertility for other reasons very specific to that area ( ancient basalt lave flows on surface, the plateau slopes back away from the escarpment ( unusual ) , high rainfall due to it being a far easterly extension of the 'Great Divide' (coast from inland , basically), so... high rain fall, low run off and erosion, basalt underlay + lotza years = 'krasnozem'






Which may look like , inland 'soil' but it isnt .

... and just down the hill near my place



Not dry or desolate at all!
Now, inland , and in other areas where those factors are different the soil is very infertile as its so old, worn out, leached, etc .

For the extreme. if one goes to the craton areas ... Pilbara, Yilgarn, etc . much more so .

https://en.wikipedia.org/wiki/Craton

This I think is the main reason a lot of Australia has such poor soils . Of course, continual fire, natural or spread by humans will have an effect , yet we have to realize, one of the main uses of fire stick was just not for 'farming' but to stop bigger more destructive burns gaining moment . So, without the fire stick management, the impact of natural fire may have been worse .

regarding animal manures, I remember from BD once we did a table of all different manures fertility , eg, chicken is high, cow, horse, sheep, is lesser but good, kangaroo is very poor. So unless we could access the quality off mega fauna poo-poo ..... ?

But I think the things I mentioned first , which basically boils down to geology and geography, would far outweigh the loss or gain from long term mega fauna - or not .

I guess the other thing to do is look at why the other areas ( like Great Planes in USA for eg) are fertile and how those soils were formed ... something I have little knowledge of .
 

Ayrton

Ad Honorem
Jan 2017
4,264
Bendigo
I doubt it as now we are only just acknowledging their techniques and are asking them to show us . We train them in what we know and they train us in what they know :)




Ten Aboriginal Land Management Team members from the Hunter recently received TAFE certificates after completing basic firefighting training with the Rural Fire Service. This was followed by an Indigenous fire management workshop led by Indigenous fire practitioner Victor Steffensen. During the event Victor conducted a traditional burn.

That is all so encouraging! Respect both ways! Love it! :cool: