Understanding: Landscape Hydrology

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duane
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Re: Understanding: Landscape Hydrology

Postby duane » Sat Jan 15, 2011 8:07 pm

Quote
The natural systems has been so hugely changed by man, often for very good reasons. and this often cannot be undone nor is it always desirable to do so.


Man always has believed that he could mould the natural world to his own vision.

Show me one civilisation that has been successful? and endured to tell the story. Most are buried under sand and mud. Just what we are witnessing today in many parts.

Paul Sheehan's recent article is worth reading. Titled 'Floods steal precious topsoil - and future goes down drain' you can see the full article here http://www.smh.com.au/opinion/society-a ... 19jrq.html

The following is a short extract from that story.

We changed the landscape and so changed the weather..."
Australia reminds me of an injured person, gushing blood. Others gather around, concerned, yet nobody mentions the gushing blood, or appears to even notice.

Last night there was a telethon in support of people who have suffered from the floods in Queensland and there has been much discussion of the costs to the economy, the cost of recovery, the cost of lost coal exports. But there has been little discussion of the more fundamental issue. The rivers have been running brown. A lot of the lifeblood of this country has been gushing away in liquid mountains we don't even see.

A few sages warned that the worst thing that could happen to Australia after a decade of drought was sustained rain.

That is what happened across much of the eastern food basket. The sequence of extremes was not global warming, nor was it bad luck. This was an Australian-made disaster that was a long time coming.

The rivers have been dense with topsoil because so much of Queensland and NSW sat dry and vulnerable after years of so little rain.

I have heard some people comment on how pleased they are to see loads of new topsoil washed into their area by floods. But one district's gain is another's loss, and that loss is permanent. Australia's thin topsoil was the resource the European settlers exploited when they began to transform this country. What they didn't fully understand - and apparently it is going to take us 200 years to wake up - was that the landscape had already brilliantly evolved to sustain itself in a dry climate.

We came, we saw, we buggered. We've managed to fool ourselves that the soils have remained fertile by the illusion created by fertilisers which, while keeping crop yields high, have gradually exhausted the soil.

Some sense of the gravity of what blood rivers mean is provided in Dirt, the Erosion of Civilisations (2007), by David Montgomery, who teaches geomorphology at the University of Washington. He is a past recipient of a prestigious MacArthur Fellowship. His book's thesis is profound: ''Even if we take it for granted we know that good soil is not just dirt. When you dig into rich, fresh earth you can feel the life in it … While the world's population keeps growing, the amount of productive farmland began declining in the 1970s and the supply of cheap fossil fuels used to make synthetic fertilisers will run out later this century. How we address the twin problems of soil degradation and accelerated erosion will eventually determine the fate of modern civilisation.''

Dirt charts the history of soil depletion from ancient Greece to modern times. A depressing pattern sets in and never changes. When societies exhaust their topsoil, they collapse or are forced to move. The age of mechanisation merely sped up the process.

The history of Australians' ignorance in the management of water, and thus soil, can be found in The Water Dreamers (2009), by Dr Michael Cathcart, a lecturer at the University of Melbourne. He argues, compellingly, that Australia was settled amid ignorance of how the natural landscape conserved water, soil and vegetation. None of this would surprise anyone who paid attention to Professor Jared Diamond's visit to Australia a few years ago, or read his book, Collapse: How Societies Chose to Fail or Survive (2005), or listened to Australia's most famous science intellectual, Dr Tim Flannery.

But the most specifically prescient warning for Australia came from a most eccentric source, Peter Andrews, who predicted that after the drought eventually broke the rivers would run red and brown with the soil that had been sitting on the baked and denuded landscape.

ghosta
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Re: Understanding: Landscape Hydrology

Postby ghosta » Sat Jan 15, 2011 8:13 pm

Shirley, my apologies if you are unable to understand the answers to any questions that I answered, I would be pleased to explain them in different terms so you can understand..... if you would be so kind as to explain which ones you have trouble with. Dont feel alone in being unable to absorb some of the NSF concepts, this is what these forums are for- ask away!

duane
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Re: Understanding: Landscape Hydrology

Postby duane » Sat Jan 15, 2011 10:04 pm

Shirley

We continue as humans not to learn from history.

We continue to do so at our peril, so I believe.

Governments and Bureaucrats have allowed ALL of this to happen....they planned for this failure. Now they are blaming it on Nature. Typical....buck passing. Policy decisions overiding and ignoring existing environmental knowledge.

The people of Qld could and should mount a class action, as many will not be covered by insurance.

The State is meant to protect its citizens, not bury them under a sea of mud.

Clearly, as this article (you posted a link to) highlights, the State failed AGAIN!!!

ghosta
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Re: Understanding: Landscape Hydrology

Postby ghosta » Sun Jan 16, 2011 8:23 am

Duanne how do you imagine a "class action" would be sucssfull? Why do you blame the government, what exactly have they done wrong? You say they +planned for this failure" yet the reverse is actully true; havent you heard of the Wivenhoe dam? Of course if it was larger it would have been better, but to be fair governments cannot plan to completely elimate all risks; we are dealing with nature which has shown itself to be unpredictable.

Obviously a dam in the Lockyer Valley will be needed and there will be studies conducted throughout Australia to determine similar area at risk of freak events and more dams built or other protective structures like levies built.

It would be usefiull if you were not hellbent on a smear campaign and started making usefull sugestionion. Any fool can make criticisms in hindsight, but its even worse when the criticsm are generaliased and with little foundation.

duane
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Re: Understanding: Landscape Hydrology

Postby duane » Sun Jan 16, 2011 9:46 am

Ghosta you must be a bureaucrat!!!

Local Government has records of the 1:10, 1:20. !:50 amd 1:100 floods levels.

Both State and Local governments have permitted building in flood prone areas. QED.

You, like they, want ALL the blame to go to Mother Nature....you are another buck passer.

There is a MAJOR problem with your dam theory and it is this:

If 100 rain drops fall on the Australian Continent only 2 drops end up in storage dams !!

Few Australians are aware of the fate of water when it hits our landscape. On average, of every 100 drops of rain that fall:

•Thirty drops are absorbed and transpired by vegetation and crops.
•Six drops are added to groundwater.
•Twelve drops enter our creeks and rivers (of which two are lost and four flow to the sea).
•Two drops enter our dams and storages, of which:
•1.6 drops grow our food.
•One-third of a drop is used by industry.
•One-tenth of a drop is used in our homes, parks, ovals and for other uses.
A massive 50 drops out of the 100 wastefully evaporate.
Taken from http://www.sciencealert.com.au/opinions ... 21562.html

All of the $$$$ spent go into infrastructure to save the 2 drops.!!!LUNACY

This is a TOTAL waste of resources when if we can show how greater storage into floodplain aquifers and soil storage could capture and hold 10 drops of that 50 that evaporate then we would have 5X the storage capacity in all our dams and we could mitigate flooding and have environmental flows slowwly releasing water back into our rivers and streams.

You would NEVER be able to build a dam to capture the unlimited maximmum flood but the landscape used to be able to deal with it when all our wetlands, creeks and streams were not incised. The engineered drainage and dam paradigm is a total failure in the long term.

We need to be closely looking at how Nature dealt with these issues and mimic Her.

COMPRENDE ???
Last edited by duane on Mon Jan 17, 2011 10:44 pm, edited 1 time in total.

Shirley Henderson
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Re: Understanding: Landscape Hydrology

Postby Shirley Henderson » Sun Jan 16, 2011 11:05 am

What is it that you do ghosta? Science, hydrologist, farmer, conservation ???
Last edited by Shirley Henderson on Sun Jan 16, 2011 10:29 pm, edited 1 time in total.

ghosta
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Re: Understanding: Landscape Hydrology

Postby ghosta » Sun Jan 16, 2011 11:38 am

Duanne, think about the statistics you have quoted.

If there is a prolonged and heavy downpour of rain when the ground is already saturated do these statistic apply? Well it may be a surprise for you to hear that nearly 100% ends up as runnoff. Thats why floods ocurr. And thats why dams can assist to control floodwaters.

I cannot believe you are so naive to imagine that the natural landscape was able to absorb floods of major proprtions- how do you think flood plains with deep silty soil came about? where did that soil come from? And why did the early explorers find it so difficult to find the entrance to the Brisbane river amongst a broad band of mangroves built on silt. This silt came from somewhere- upstream, during floods.

Looking at the present situation what PRACTICAL options do you suggest other than dams and levees to handle the sorts of rainfall encounterd recently? Im looking for affordable and realistic solution not some generalised wild idea that cannot be implimented.

duane
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Re: Understanding: Landscape Hydrology

Postby duane » Sun Jan 16, 2011 6:24 pm

Water storage as soil water
One way that we can store water is in the ground. The following shows the enormous capacity for ground water storage.

1 cubic meter soil weighs about 2 (tonnes)
over 1 ha (10,000 cu m) that is 20,000 (tonnes)
In that 1 m depth increase water content by (%) 10%, 20%, 30%, additional water (tonnes) would be 2,000, 4,000, 6,000

So 1,000 l =(tonne) 1
so in 1 ha = 2000 tonnes
0R in litres 2,000,000
OR in meglitres 2

1,000ha stored water (Ml) 2,000 4,000 6,000
100,000 ha stored water (Ml) 200,000 400,000 600,000
1 million ha stored water (Ml) 2,000,000 4,000,000 6,000,000 This is the volume of water in Sydney Harbour

The area covered by the recent Qld floods was >460,000km2.

I'll let you do the maths of how much water that could be stored by mimicing and therefore reinstating some of the original landscape functions.

duane
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Re: Understanding: Landscape Hydrology

Postby duane » Mon Jan 17, 2011 10:38 pm

Floods and Droughts are the natural pattern in Australia for water and fertility movement. Always was, always will be.

These two extremes exist almost uniquely to Australia.

As too, the unique landscape efficiencies that Peter talks about in his books.

Europe, as we know, has a different water and fertility pattern. It has, every year a fall, then a freeze, followed by a thaw that is regulated by increasing hours of sunlight.

Australia, on the other hand, has the longest hours of sunlight of any continent. We also have a rainfall pattern that is eratic and is only 300mm on average across the whole continent. The average evaporation rate is 2000mm.

How did anything grow and survive???

The answer to that is in Peter' two books.....it was the unique efficencies and landscape components, patterns and processes that existed in the Australian landscape.

THAT IS THE FIRST LESSON we all need to learn....that this landscape IS/was different in so many ways, that even today many do not even accept or understand these differences.

Australia has had floods and droughts for millenia.....no question.

It's is also very flat.

And as we have just seen can be in drought for 8-10 years.

What used to happen before white settlement, after prolonged periods of drought??

The rains would come. That was THE PATTERN.

Floods would run across the landscape, very slowly, because the landscape was so flat.

But these were very different floods to those we currently witnessing.

Prior settlement, we had 94% more wetland systems in tack. Today we have only 6% of our wetland systems in place.

These wetland systems or COMPONENTS played a unique role in our waterways.

They choked the streams and rivers at various intervals down the length of the reach and they allowed for a trickle flow.
In peak flows they acted to SLOW the water down and to disperse it gently across the floodplains.

Peter describes this in his book, Back from the Brink, as a unique feature Haikai Tane described as a stepped diffusion system of braod-acre hydroponics.

This pattern was a rehydrating pattern. Floods moved SLOWLY and relatively gently across the vast plains sometomes taking many months to travel across vast distances filling floodplain acquifers as it moved. The clays that had cracked open with the drought would fill the ground with water. This was part of the unique efficency of the Australian landscape

Compare that with today.

How do we know this was the previous pattern??

The floodplains were thousands of years old....sediment laid down by water. These floodplains could not have been built if the process was an erosive and incised one, like it is today.

The unique efficiency was this landscape had devised a system which prevented the minimum erosion from happening i.e., a headwall cut and also allowed for the maximum capacity to flood without causing destructive damage.

Our early pioneers NEVER recognised these unique features and our present generation are still ignorant of them.

We have effectively dismantled completely what Nature had devised as a perfect system of natural irrigation in our floodplain system...what Peter calls grass covered dams. Hard hooved animals have seriously impacted the cracking clays and we have drained our wetlands.

Today our rivers and streams are mostly incised.

Their wetlands mostly cleared and gone.

And the riverine/floodplain connectivity is almost gone.

How do we reinstate the system??

The simple answer is we CAN"T.

Infrastructure is built over much of our river banks and floodplains. This has to be protected. Levies can do that unless we see a 1:100 or a 1:200 flood.

But what we can do to much of the area not covered by important infrastructure is too mimic the functions and patterns of the 'old system' and reinstate some of the functionality to compensate the land for it's losses.

This is what Peter has done at Tarwyn Park.

In the 'old system" all of our rivers and streams were a series of contours caused by biological interuptions....wetlands. These were NOT rivers and streams as we knew them to be in England but rather a series of ponds or lakes (Sturts dairies).

Peter has created these contours both in stream and off stream.

By taking a contour off stream, water can be taken off in steps as it once was.

We can run contours for miles across the landscape even to different catchments. And we could put in storage dams in sequence at the high water level of the dams. This would allow us to store huge volumes of water and to rehydrate and spread the fertility to the high ground as the landscape itself once did automatically.

But first we need permission from the various regulators to do all this.

As for future floods......Councils should not allow any development on areas known to flood.

That part is simple really....build ABOVE the historical flood lines.

Build in or on a known floodplain...guess what?? You will get flooded.

ghosta
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Re: Understanding: Landscape Hydrology

Postby ghosta » Tue Jan 18, 2011 9:39 am

Shirley Henderson wrote:What is it that you do ghosta? Science, hydrologist, farmer, conservation ???

Shirley I am "retired", although not yet of retirement age so I guess you could call me an "investor". I am also a forester, with postgraduate studies in natural resource management. I have worked for both public and private organistations in forestry, and land management, athough the bulk of my career was in various roles in rural firefighting organisations. Raised on a farm. Hope that answers your question.

ghosta
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Re: Understanding: Landscape Hydrology

Postby ghosta » Tue Jan 18, 2011 10:01 am

Duanne a coupe of points-

"THAT IS THE FIRST LESSON we all need to learn....that this landscape IS/was different in so many ways, that even today many do not even accept or understand these differences."

Why is that? I suggest is most people are not even aware of the difference. And if they do, the landscape has changed so enormously they realise that trying to reproduce some of the original landscape functions today on a large scale is such a huge task that noone so far knows where to start.


"Our early pioneers NEVER recognised these unique features and our present generation are still ignorant of them." As Peter points out in his book"Back from the Brink" much of the damage to the original systems had already been done by the indigenous inhabitants. How much influence continntal drift and associated drying out of the continent had in weakening some of the systems is also relevent.


"But first we need permission from the various regulators to do all this." To do what actually? Sounds simple, but this is the greatest barrier to progress, and simply will never happen unless the public agree on a plan and want it to happen. Look at the problems the Murray Darling Basin Authority has encountered with the public, multiply this by whatever factor you think appropriate and you will get some idea of how difficult the task is.

duane
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Re: Understanding: Landscape Hydrology

Postby duane » Tue Jan 18, 2011 10:15 am

It ain't easy, I agree.

I've never stated it would be easy.

If it was Peter would have stopped trying 30 years ago.

Shirley Henderson
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Re: Understanding: Landscape Hydrology

Postby Shirley Henderson » Tue Jan 18, 2011 2:25 pm

Thank you Duane for that very clear explanation about flood plains. Aslo thanks Ghosta for letting me in on your personal history. Ghosta, since you are almost retired, why don't you get behind Peter and help him. As Duane says there are ways to restore some functioning floodplain systems. It' getting the knowledge out to the people and the people that matter. This is the time for loud voices and positive action. I am sure you have your heart in the right place Ghosta and just have different views and experiences about the way to do things. We need a concerted effort. I have heard you comment on Peters work in admirable ways at times. You know the old saying "If your not with him, your against him". Sure there are more ways to skin a cat but choose your battles carefully. Peter is worth supporting.

duane
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Re: Understanding: Landscape Hydrology

Postby duane » Tue Feb 01, 2011 10:02 am

I think it appropiate to repost Shirleys post to this thread.

See viewtopic.php?f=12&t=850

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Re: Understanding: Landscape Hydrology

Postby webmaster » Fri Jul 20, 2012 10:09 pm

Connecting people to people and people to place

See pictures and full article here - doc file

Over the past 15 years I have been working closely with the Welfare Industry, Dept of Education, Dept of Juvenile Justice and Dept of Housing, and have been regularly recognised for my work in developing, co-ordinating and supervising some of their most successful programs.
As well as building community spirit, these programs also connect people to their local environment, transforming degraded urban areas into natural wonderlands - areas that become the central focus and meeting places for the people.
All of my programs include the construction of ground projects, such as the demonstration model of an urban storm water catchment and filtration system I built with young men from the Frank Baxter Juvenile Justice Centre at Kariong.
This project was aimed at demonstrating the ease at which we can solve our current water crises and the outcome has seen the Detention Centre now filtering and capturing much of its storm water runoff. This program won the “Chief Executive’s award for excellence”

TOP LEFT – Young men from the detention centre begin preparing the site. You can see the empty storm water channel in the background. TOP RIGHT- Soon after constructing a series of dry stone weirs in the storm water channel, the water seeping from the ground soon filled the channel and it began to flow.

TOP LEFT – Storm water system under high flow. The weirs create a series of ponds that slow the flow of water and allow infiltration into the ground. This process not only fills the ground table it also reduces the volume of flow within the channel that intern greatly decreases urban flooding downstream. TOP LEFT – Just over a year after construction of the weirs, the channel had developed into a natural stream, not only does it look like a natural stream it also behaves like one. The recharge of the ground table during rain events then seeps back into the channel maintaining its flow during dry periods. The bulk of the water in this system is stored under the ground.
I have also constructed an Urban Food Forest and Community Park at Debra Ann Dr, Bateau Bay, where we engaged the local unemployed to design, construct and manage the entire project. Some of the first students are now supervisors.
As part of my innovative Natural Food Production System, the site also includes the first hanging swamp to be returned into our urban environment as part of a storm water catchment and filtration system. The storm water system also doubles as an in-ground irrigation system for the parklands and gardens. This project has been acknowledged by the Welfare Industry and Dept of Housing as an exemplary model of community building.


TOP LEFT – Local residents begin the massive construction project on a severely degraded vacant block within their housing estate. TOP RIGHT – The entire garden was hand built with around 100 tonnes of stone going into its structure, no machinery was used during construction.

TOP LEFT – I run all my programmes as a certificate 2 course in Conservation and Land Management and adjust the subjects to suit the ground project. I include landscape construction as part of the community garden programs. TOP RIGHT – In less than a year the garden was complete and producing large volumes of food. You can see the terraced gardens and natural food forest in the background.
Local police have also engaged with me on some of my larger projects where they have recognised a reduction in anti-social behaviour within some of our most disadvantaged communities. The reduction in crime acknowledge by the police has lead to some discussion about working co-operatively with me in the future to develop more community building programs.
I have developed a community network over the years and a lot of my success comes from working co-operatively with many other groups and organisations. By developing a community network of social services that engages directly with government departments we, the community, can find the solutions and develop the programs and ground projects that otherwise get tied up in red tape.
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The Forum for Peter Andrew's Natural Sequence Farming


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