The Waterright philosophy
Soil regenerationIn the early 1970''s I was looking for a life style change and bought myself a small holding - an old goat farm. I wanted to grow my own food - I had been brought up with growing food - as I often say I was borne and Hitler declared war - a case of gross exaggeration.
However the goats had totally destroyed all the top soil - a wet gluey mess in the wet - hard as concrete when it dried- so I was faced with the problem of how to regenerate the soil.
Now it just so happened that this was the era of giant dust storms, with millions of tonnes of top soil being lost. Fortunately now farmers have learned the value of top soil and changed there farming practices but I had no idea that was going to happen.
I just saw a potential calamity if the world lost too much of its top soil so soil regeneration became my out of work interest.
Fortunately my company, writing computer simulation software, by then was becoming successful. It was eventually to become the international leader in its field and one of Australia's leading exporters of technical software.
So here was a research project I could delve into. I did not have to worry about money or getting any financial return, it was a project I believed was important for the future of humanity.
The success of my company was based on what I termed speculative research. There is a general feeling, particularly by those who finance research, that science has to be cautious, carefully cross checking every detail before moving on. This attention to detail is certainly part of the scientific process but major innovations often come from 'way out' experiments which many would see as totally ridiculous.
The cost of innovation is the willingness to make lots and lots of mistakes and be made to feel ridiculous with your peers. This was the philosophy I used in my soil regeneration experiments.
When I read the literature on soil regeneration it seemed that it was inevitably a slow and tedious process with regeneration rates measured in mm per century. I have always been an impatient sod and wanted a system which could regenerate soil in a few years.
I looked around for anything that may regenerate soil, the local garden stores must have loved me as I bought up anything that looked as though it may help in soil regeneration, so called clay breakers in bottles bags and by the trailer load, plus weird and wonderful plants which were supposed to be ploughed back into the soil to improve structure.
I then divided my block up into a series of little squares, in what I thought was a nice scientific approach, with control and duplicate squares and some with combinations of processes and we were off.
Now it has to be said as a piece of scientific research this was a total failure. True some squares did show significant regeneration, others remained there glue to concrete characteristics. The single variable experiments seemed a total failure - there had to be a combination of processes, green manure and selected additives etc.
But it seemed impossible to see any order from the confusing results. I then stumbled across a mathematical technique called the Taguchi approach, widely used in Japanese industry to analyze multi variable problems. Even this failed to make any sense of the results.
The cruel reality was that I could have a certain set of variables which appeared to work really well on one bit of soil, then if I tried to duplicate this success in another area it could just as easily fail.
The only comment that could be made about my experiments, which had been going on for a number of years that they were a total shambles with no clear cut conclusions.
Now in my every day business of computer simulation there was a fundamental rule which I used in these experiments. Simulation involves writing code so the computer acts just like the real world. This involves developing an algorithm which should represent the real world then testing to see if the results look anything like what actually happens.
Of course the simulation is never exactly the same as the real world so it is necessary to introduce tuning factors, a posh name for fiddles, until the simulation gives reasonable accuracy, when it can be used as a design tool. Normally this involves multiple reiterations until the simulation is reasonably accurate.
Now there is a fundamental law about simulations. If you find that you are developing millions of lines of code, with a myriad of correction or tuning factors, then this means the basic algorithm is wonky, and however much effort has been invested it is time to start over again with a new base algorithm which is a better fit to the real world.
This was just what was happening with my soil regeneration experiments. It was clearly a waste of time trying to work out some magic formulae of so much of ingredients x, y and z combined with another combination of green manure crops and yet another combination of soil working. It was just getting far to complex to come up with any rugged method of soil regeneration.
I had to look beyond the results and find try and understand the mechanics of how the soil was being regenerated, e.g. look for some generic rule or law which can be reliably applied in most situations. I needed a common theme.
So I had to look again at my experiments to see if there was any common themes, outside the variables I was trying to control. It soon became clear that water was playing a crucial role. Now a paddock my look pretty uniform but this is rarely the case in nature. Now my paddock certainly did not even look uniform, for a start it was slopping down to a creak.
I used the creak to irrigate the paddock by using a small dam and pump. As I looked at my little squares and examined my soil samples it was pretty obvious that the water varied significantly. As I looked around for the reason it became clear that the subsoil had fissures which led to the formation of underground flow paths. Not really creaks but enough to give a preferential pattern to the water flow paths.
This mean that some areas would become quite dry in the hotter months while others areas would be wet and almost boggy during the wetter months.
There only areas showing regenerations were those where the moisture level happened to be kept moderate and uniform throughout the year. The areas which were too wet or dried out in the heat showed little regeneration.
This was an important observation but it was not the real answer, water is inert and by itself will not regenerate soil. I concluded that the key was the micro-biological activity in the soil. This was confirmed by the number of worms in the soil. Worms cannot eat organic matter directly - it has to be processed by microbes first.
As I tried to get my head around microbiology I realized just how complex a subject it is with a totally bewildering number of species known and probably an even larger which have yet to be identified.
Scientist require an understanding, but I am an engineer- I am used to creating things without having a complete understanding of the tools of my trade. Advances in technology are full of examples where an engineer has made a major leap forward with just an instinctive understanding and later the scientific process develops the in depth understanding.
I did not need to have an in depth understanding of soil microbiology, all I needed was to understand the conditions which would lead to the proliferation of micro biological activity. Clearly microbes need food, which is readily supplied but equally they need the right moisture conditions.
This is not so easy in Australia where the majority of the land mass has an evaporation greater then the rainfall, and over much of the continent evaporation is multiples of rainfall.
At first sight it looks impossible to maintaine moisture levels under such dry conditions. However the top layer of the soil will soon dry out to form an insulting crust which prevents further evaporation so the sub soil can be maintained moist even though the top crust is dry.
To exploit this effect needs a rethink of how we manage our water.
My task was therefore to find out how to manage soil moisture which lead me into the world of irrigation scheduling, subsurface irrigation, water harvesting and later the wicking worm bed which is undoubtedly the most successful method. These are described in the following chapters.
At that time, it is some thirty years since conducted those experiments I had no idea about global warming. With hindsight I now realize that these early experiments a major implication for capturing carbon in the soil.
In the next chapter I will describe my experiments on irrigation scheduling.
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