Water, Life Or Death
The deterioration of the land which is caused by perennial irrigationis of special moment for the Human Environment Revolution.
The basis of landscape design is water in association with land;a principal factor for the improvement of the landscape is the better use of water,yet the destruction of land by irrigation has kept pace and very often exceeded thatcaused by other wrongful agricultural practices.
There are the two movements in the soil which come from outsideit; the first is air, the second is water. The movement of air into and out of thesoil and the movement of water into and through the soil cannot be separated.
It rains! Water goes down into the soil and pushes out the air.The rain stops! The free water drains from the soil and sucks air back in. Much waterremains trapped in the "crumbs" of the soil structure and as a film coveringthe particles of the soil. The kind of association of air and water in the soil hasbeen a principal factor in the fertility of the soil.
The most fertile natural soil for the production of good foodfor the welfare of man and his animals was in the natural grasslands where the rainfallwas moderate. Where the rainfall was much below 16 inches annually the minerals necessaryfor the production of high quality complete protein were not so readily available.But where the rainfall exceeded 30 inches, the extra amount of water going down throughthe soil had not only speeded up the process for the release of the nutrients minerals,but had partially overcome the capacity of the organic matter in the soil to retainthem. They were leached downwards to deeper levels in the earth or washed away. Inthe regions where the temperatures were higher, both of these reactions were morepronounced.
The health and constitution of animals from the over-dry andthe over-wet natural regions is markedly inferior to those produced in the regionsof moderate rainfall, (16 to 30 inches). For instance, the thigh bones of rabbitsfrom both the wet and the dry regions are of almost tissue paper thinness comparedwith the normal thick and strong bones of rabbits from the moderate regions, (W.A. Albrecht, "Soil Fertility and Animal Health", and his concept "insolubleyet available").
These simple natural facts relating to air, water and soil,illuminate the problems of irrigating the land and the reasons why some irrigationschemes have been successful and many others have destroyed land.
Thousands of years ago a method for creating fertile soil andfor irrigating, was developed in Egypt along the River Nile. This river overflowedeach year with precise regularity carrying with it and spreading over the land, greatquantities of silt of both mineral rock and organic origin. The early Egyptians divertedthe richly laden water behind banks and in canals, to far beyond the limits of thenatural flood plain. The water was finally led into embanked fields where the richsilts were deposited and the water soaked into the dry land. Countless millions ofworkers soon cultivated, mixed and aerated the soil: they were not people; they wereEgyptian earthworms. Crops were sown and later harvested without any further waterfrom the Nile or from rainfall.
This is the "basin" system of irrigation. It was permanentand successful and it did not deplete the fertility of the soil, but improved it.It is a system of irrigation which, on its long record, may be classed as universallysuccessful. It is based on one inundation, then a cultivation and sowing when thesoil has drained sufficiently. One application of water grew the crop to maturity.
This was the system of irrigation used in ancient Egypt. Butnow things have been changed. The Nile has been dammed to create large reservoirsfor perennial irrigation, so that the same land can be watered periodically to growcotton and other crops. The silts are also impounded with the water and remain lostforever in the reservoirs. Now the Egyptians will need to develop real skills inthe management of their soil otherwise their agriculture will follow the chemicalway toward destruction. Artificial fertiliser will trigger off invasions of new peststo be poisoned with ever more potent insecticides. This is already happening andthe polluted Nile waters are helping to turn the Mediterranean into another deadsea and causing a great loss of food from the sea for the people of the Mediterraneancountries.
Bordering on China, Russia and India is the Hunza, the regionof a stream where for over 2,000 years people lived on, and irrigated, the ridges.Almost completely isolated from the rest of the world, conjecture has it their ancestorswere a few soldiers from the army of Alexander the Great and their Persian wives.These people in the first place were raiders of the caravans of traders on the nearbyroute between China and India. Here in their uncompromising fastness only 100 mileslong and narrowing in places to a couple of miles wide they developed a healthy agricultureby taking water from melting glaciers along constructed channels to terraced fieldsand rock gardens. Soil for their irrigation land was carried up laboriously fromlower levels and built up by composting all the wastes of plant and animal life.In this system of irrigation, good aeration of the soil was maintained by excellentdrainage--always an absolute necessity. The compost spread on the soil maintainedan excess fertility in the humus which added and retained the minerals. Sir RobertMcCarrison, a medical officer, seems to have "discovered" the Hunzacutsfor the western world about 50 years ago and referred to their outstanding healthand vitality in his Mellon (1921) and Cantor (1936) lectures. In his book "Nutritionand Health" he reports that the Hunzacuts are unsurpassed in perfection of physiqueand in freedom from disease. Their food consists of wheat, barley and maize, vegetablesand fruits, milk and butter, and meat on feast days. They grow an abundant crop ofapricots and "among these people the span of life is extraordinary long."
In sharp contract to this successful system of irrigating theridges, is the wide failure of perennial irrigation. Man loves to boast of his irrigationmaking the desert bloom. Of course the desert will bloom--for a time. The desertlands had too little rainfall to release the mineral elements of plant nutritionso they remained richly endowed with minerals. The irrigation water first aids theirrelease causing plant life to luxuriate. And all would be well if the soil was managedrationally to create a store of humus and surplus fertility. Instead, because watermade the desert bloom, the emphasis is too generally on water alone and not on soilaeration or on developing a humus laden soil which would both extend the value ofthe water and prevent the leaching of the minerals from the soil. When eventuallythe irrigated land does not bloom so well, the reduced production is often blamedon too little water so more is added to cause more leaching and less aeration. Thishastens the destruction of the soil by either the formation of alkali land (salting)or by water-logging.
This process of soil destruction took many decades and in earliertimes the cause was often seen and understood and remedied by spreading dressingsof dung on the land, by green manuring and by hand cultivating to aerate the soil.Where water was in short supply the remedies were often found more quickly than inthe presence of abundant water. However, with the general advance of the bastardisationof agriculture, soil destruction by perennial irrigation was speeded up to becomea shorter term process.
For instance perennial irrigation in Australia is little morethan an infant in age, but already is has succeeded in destroying much land and inplacing in extreme jeopardy the greatest natural region on the continent--the MurrayRegion--which includes parts of Victoria, New South Wales and South Australia. Buthere the deterioration and impending destruction is not caused by agriculture alone;there are other causes and other culprits.
The real trap seems to have been the status deal of keepingup with the Joneses--in our case, the American Joneses. Australian politicians hadseen the earlier irrigation schemes in America and been greatly impressed. They receivedthe enthusiastic support of many people in this country, particularly of the engineers,who, with politicians are not unaffectful by the urges of 'status'.
But things were quite different in the U.S.A. Firstly, theyhad vast waste storages in snow and ice, which started to melt in the spring to keeptheir great rivers flowing through the summer and autumn, (fall). It was only necessaryto divert the water from the rivers on to the dry land. Secondly, America had a rapidlyrising population many times greater than Australia has now, to buy the higher pricedproducts of the irrigation land, such as the fruits and vegetables.
In Australia there were no frozen water assets to keep inlandrivers flowing in the summer. They often cease flowing altogether. The enthusiasticpartnership of politician and engineer disavowed the changed circumstances and brushedaside the views of their more rational opponents.
The construction of big dams at high cost started and has beenkept going ever since by an extraordinary effort of successful public relations,not unassociated with national status symbols. Australians, like most other peoples,are suckers for status symbols, but unlike others, Australians have no idea whatthe symbols have cost them. Australia started to make the 'desert bloom'. With theaid of a national water wailing fixation about being the driest continent, we havebeen persuaded to overlook the fact that on a per capita basis, we are extremelywater rich. The result now is that we have more unprofitable irrigation land to populationnumbers, than any nation on earth.
The expressed intention from the earliest irrigation projectsuntil the present day, was that government irrigation would be paid for by the farmers,but despite the make-believe of cost/benefit studies, this prospect was discardedby governments long ago. They are seemingly satisfied if the actual cost of reticulatingthe water to the irrigation farmers is recovered. There is no possibility of recoveringthe cost of the high priced storages or the often more costly reticulation canals.
However the point of non-recoverable costs or even the inflationaryeffect of the squandering of large sums of public moneys, is not so much the issuehere. Rather it is concern for the environment and the direct destruction of land.
The failure of irrigation from the point of view of the landscapeis occasioned by the design of the system which was done by engineers. Recently theMurray Valley Commission, who control the Murray Waters, received the report of theMurray Valley Salinity Commission which it commissioned in 1967 to seek the causesand to find the cures for the destruction of irrigation land by salting--the 3,000years old problem of irrigation land. This report on an important landscape matterand one which should have received wide comment, was not noticed in any news mediaof mass circulation. The following references are taken, therefore from a small Victorianmonthly "Irrigation Farmer" November issue, 1970 and December-January issue1970-71. Headlines include, "SALINITY REPORT PROPOSE HUGE REMEDIAL EXPENDITUREFOR MURRAY AREAS . . . . . "MORE THAN A MILLION TONS OF SALT ANNUALLY POLLUTESTHE MURRAY RIVER." "BEAT THE SALT PROBLEM OR ABANDON THE AREA" andgoes on to say "The facts of life will force all water users (farmers in governmentirrigation districts) to unite in common brotherhood for their own eventual survival"and "The clear warning in the Salinity Report of the inevitable consequencesof accepting the continuing deterioration of the irrigated lands of the Murray-GoulburnRiver systems justifies a searching review of the priorities of reclamation of theexisting irrigation areas--or of the construction of new reservoirs that encouragedemands for the opening of new irrigation districts."
This last statement seems to be asking; should the pollutedland be abandoned and new dams built and new canals constructed to supply water tonew irrigation districts to ruin more land and to pollute the rivers? Yet of thepublic who pay for these highly photogenic government irrigation catastrophies, howmany have even heard of the Salinity Report?
Government irrigation in Australia is an enormously high pricedecological and landscape disaster caused by irrational engineering design and agriculturalpractices which are anti-landscape in their methods of handling water.
Our agricultural water developments have started at the wrongwater-line--the drainage line of the river after the water had left the land, insteadof at the water-divide line of the main ridges and retained the water on the landa little longer.
THE HUGE REMEDIAL EXPENDITURE mentioned by the magazine is $110,000,000.It is by no means 'huge' by comparison with the original costs or with the damagealready done to the region. A particularly disquieting aspects of the "SalinityReport" is that it was produced by engineers and proposes an engineering solutionfor a calamity of engineering design. There was no report of any solutions, alternativeto engineering, having been sought for the salt problem from the less financiallyinvolved sciences of the ecologist, the biologists and other more landscape orientatedprofessions.
However, these matters illustrate that water can be life ordeath to the landscape. The wrong handling of water by state governments in Australiahas turned the good water of costly irrigation storages, into a powerful instrumentof pollution. This, along with other crimes against the landscape in the region,could make the Murray River become what is already has been called--Australia's largestsewer.
The two irrigation procedures which have been suggested forlandscape design--Keyline pattern and flood-flo--are perfect drainage methods andmaintain good aeration in the soil. They provide close control of water to supplyenough but not to over-water and water-log the soil. That is why they are describedas soil making procedures.