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4. Perception of desertification in the murray mallee of southern Australia
R. L. Heathcote
Desertification in Australia
The extent and severity of desertification in Australia has been documented in several recent publications. The Commonwealth government provided a national report and a case study of a pastoral district in semi-arid Western Australia for the UN Conference on Desertification in 1977 (Australia 1977;Williams,Suijendorp,andWilcox 1977). In 1978 a special edition of Search (the journal of the Australian and New Zeaiand Association for the Advancement of Science} was devoted to desertification in Australia, with articles by a variety of scientists (Condon 1978; Freer 1978; Mabbutt 1978a; Mulcahy 1978; Pels 1978; M. Williams 1978; O. B. Williams 1978). A further overall review of the problem was published by the Water Research Foundation of Australia (Mabbutt 1978b), and in the same year a national report on soil erosion in Australia appeared (D.E.H.C.D. 1978) and the South Australian government published its proposals to cope with the salinity problems of the River Murray (S.A.E.W.S.1978).
These reports provide evidence of the historical and spatial extent of desertification and provide some information on the cost to the Australian community. Thus the cost of national soil conservation measures was estimated to be $675 million over the period to the year 2000, and the South Australian plans to cope with the River Murray salinity envisaged expenditure of $23.1 million. These cash figures do not include the costs of production losses or relief and rehabilitation costs of the drought which is usually associated with an acceleration of the desertification process, costs which have been variously estimated as from about $9 million to $100 million per year (Heathcote 19791. While there is some debate on the actual monetary cost of desertification in Australia, there can be no doubt that the total is considerable. There can also be no doubt that this cost in money is supplemented by less tangible costs from the social disruption and psychological stresses associated with the erosion of what may be termed a national heritage-the physical landscape of Australia. Both the retreat of rural settlement from parts of the margins of the Australian arid zone and the thinning out of the densities of rural settlement (for reasons which included the effects of desertification) have caused hardship and stress which often have gone unchronicled.
This report therefore attempts to explain why a resource rich, commercially oriented developed nation such as Australia can provide the anomaly of successful resource development alongside evidence of a deteriorating environment. The study is oriented to one of the national problem areas-the Murray Mailee of southern Australia- where the history of land settlement and the associated environmental problems have been reasonably well documented and where a field study of resource managers' attitudes to the risks of resource management was recently completed. Whlie conclusions from the study must be related basically to the area of investigation, l believe there are sufficient parallels and similarities with other areas of Australia to make the general points move widely applicable.
The Murray Mallee: The History of Land Settlement and Desertification'
One of the most notorious examples of desertification in Australia is the Murray Mallee area, astride the South Australian-Victorian border (Fig. 4.1). At the time of first European settlement it was an undulating country of generally parallel east-west Quaternary sand masses separated by intervening flats and plains. The soils varied from coarse brown to white sands in the highest rises to red-brown clay loams on the plains between. Most soils were alkaline, well drained, but low in nitrogen and phosphorous and occasionally deficient in trace elements. In some of the plains the calcrete bedrock was exposed. Rainfall, mainly in the winter season (May-October!, decreased across the area from c. 340 mm in the southwest to 260 mm in the northeast, and the risk of crop failure from drought ranged from 43 per cent to c. 70 per cent along the same gradient (Table 4 1). With potential evaporation c. 2,500 mm and the extensive sandy soils, permanent surface water was absent and watercourses were rare, although scattered low points in the plains occasionally held brackish water after rains. The native vegetation was dominated by mallee-the collective name given to eucalypt species forming shrubby multi-branched trees 2-12 metres in height which, in dense stands, covered all but the poorest of the higher sand rises and parts of the plains. On the rises a heath association including hummock grasses (Triodia spp.) thinned the mallee cover, while on the plains open grasslands dotted by taller eucalypts and native pines (Callitris spp.) broke the otherwise continuous mallee canopy with its herbaceous understorey.
FIG. 4.1. The Murray Mallee: General Physical Setting
Source: Atlas of Australian Soils, Sheet 1, Canberra, 1960.
Despite the paucity of records there is sufficient evidence to suggest that aboriginal groups moved through the area, particularly after rains had left some surface water on the plains and in the occasional rock crevices, hunting grey and red kangaroos, small rodents, emus, and Mallee fowl. Moving in from the relatively densely populated Murray River frontages, they appear to have fired parts of the mallee as part of their hunting technology, and some of the open grasslands of the plains may have been fire-induced and maintained. Apart from these possible effects and the few campsites (little more than hearths, fired bones, and scattered worked-stone chips), there was little apparent evidence of their occupation, and the first white explorers thought they were exploring uninhabited country (Harris 1 970).
Initial European exploration found the waterless scrubs unattractive, and occupation by whites was initially temporary-pastoralists moving their flocks and herds in from the permanently watered Murray River frontages to the grasslands, like the aborigines only when some surface water was apparent. From the 1840s through the 1850s and 1860s such use was scattered in space and intermittent in time. Underground water of variable quality was discovered and some pastoral stations became permanent bases, but droughts and the arrival of rabbits in the1870 seriously reduced the available feed supplies and pastoralists suffered significant losses.
TABLE 4.1 Field Survey Site Characteristics, Murray Mallee
|Low Risk Sites||High Risk Sites|
|A. Physical Characteristics:|
|Annual rainfall (mm)||340||320||274||267|
|Growing season rainfall (mm)a||212||196||172||152|
|Drought risk (%)b||43||ca.43||ca.67||ca.70|
|1 ) Sample|
|-% of site farmers ca.33||ca.33||ca.33||ca.66|
|4) Size of farm: ac (ha)|
|Less than 1,000 (405)||26||23||3||1|
|Over 6,000 (over 2,430)||0||2||28||6|
|5) Drought experience:|
|Two (1959& 1967)||38||25||27||34|
|Three or more|
|1 00%||1 00%||1 00%||1 00|
a. Rainfall in period April to October.
b. the number of years in a hundred in which the growing season of continuously effective rainfall is less than five months. After Trumble 1948, with estimates for Victorian sites from Hannay 1965.
c. Data from field surveys 1971-72.
Prior to the 1880s agricultural land use had not been attempted in the mallee. Apart from reservations about the fertility of the soil and the shortage of water, a major problem was the cost of land clearance, since the multi branched mallee was expensive to cut down and regrowth continued indefinitely unless the roots were grubbed out. By the late 1880s, however, a combination of innovations in agricultural technology, the occupation of the remaining relatively attractive agricultural country in South Australia and Victoria, and reverses from drought on the northern fringes of the agricultural lands in South Australia (Meinig 1962) encouraged a renewed interest in the Mallee. Technological innovation significantly reduced the labour costs in land clearance and agriculture:
1) "Mallee rollers" (often old steam boilers, or tree trunks, pulled by 6-8 horses) knocked down the scrub faster and cheaper than a team of axemen, and the dead trees were eventually burned.
2) Stump-jump ploughs developed in South Australia in 1876, jigged through the stumps, the plough shares kicking up over stones or uncleared roots.
3) The grain crops were harvested by various types of mechanical "headers" developed locally from the 1880s onwards, the grain heads being chopped off,
FIG.4.2. The Murray Mallee: General Settlement Patterns
Source: Official records and Atlas of Australian Resources, Canberra, 1959.leaving the long-strawed stubble to provide a hot burn to kill off the mallee regrowth.
4) More drought-resistant wheat varieties began to appear, more suitable to the lower rainfall country. Early maturing varieties had been developed in South Australia in the 1860s and American hybrids provided further genes for local official and private innovations in the 1880s.
These events led to renewed official surveys of the mallee country and a reappraisal of the agricultural potential. The result was legislation to open up the better soils for agricultural settlement from about 1900 onwards, and a chequerboard pattern of roads, railways, grainfields, homesteads, and townsites began to be imposed upon the landscape (Fig. 4.2). Land was surveyed, road alignments cleared, and government railways built. Farmers moved in, began to clear the scrub, build homesteads, perhaps got their first income from sale of mallee roots for domestic fuel to the cities, reaped their first crops and carted them to the rail sidings for export. From the outset, this was commercial market-oriented development. Clearance of "new" land for settlement was seen both as meeting a demand from immigrants for land as a home and as meeting an international market demand for increased grain supplies. The pattern, modified in detail but basically similar in components, was repeated throughout the Murray Mallee over the period from 1900 to 1930.
Expansion of grain farming over this period was further assisted by the discovery and application of superphosphates to improve the fertility of the poorer soils and by offical South Australian government sponsorship of American "dry farming" techniques from 1906 onwards. By this method bare fallowing over a cat 10-month period was used to conserve and thus, in theory, add one season's rainfall to the next for a wheat crop every two years. Despite periodic droughts the cropped area inceased and population densities built up to peaks in the 1930s (Fig. 4.3). The apparent conquest of the "wilderness" was seen as a triumph of human ingenuity backed by official land settlement policies and transport systems.
FIG. 4.3.Trends in the Land Settlement of the Northern Murray Mallee, 1860-1970
From the 1930s, however, the process of desertification became evident. With market prices falling, the area under production (which implied also the area under fallow) was increased and the droughts and high winds of the 1930s and 1944-45 in particular reactivated the Quaternary dune systems. Crops were sand-blasted or blown away, fields lost their topsoil, north-south roads across the dunes were repeatedly buried under mobile drifts, irrigation canals filled in, railways were blocked, and farm equipment and occasionally barns and houses were buried. As bankrupt farmers walked off their properties, the similarity to the Dust Bowl in the United States was not lost on the state government officials.
As in the United States, a massive governmental response was initiated. The Marginal Lands Scheme (which operated over the period 1939 to 1961) provided Commonwealth funds (some $4 million) to buy out bankrupt or what were thought to be uneconomic farms. These were then subdivided to provide the surviving neighbouring properties with extra land to increase returns and encourage a shift in resource use from monoculture of cereals to mixed farming with sheep being grazed on rotation pastures and stubbles. In addition, the state governments wrote off some farmers' debts-which meant in some cases retailers got only one shilling in the pound (5 per cent) on their outstanding bills! -and granted carry-on loans to others.
This structural organization of the farm production system was paralleled by intensified official research activity, aimed at providing skills in controlling soil erosion, crop rotations to build up soil fertility and structure and reduce plant diseases, drought-resistant crop varieties, and hardy grasses to colonize the mobile sands. These innovations, combined with favourable (drought-free) seasons and high market prices in the 1950s,enabled a rapid recovery of the farmers' fortunes and an apparent control of the main desertification process. Such was the transformation that by 1965 confidence in the Northern Mallee had reached a new peak. Such was the general optimism that one commentator concluded in 1965 that "we can say that there is a satisfactory answer to the main (technical) problems and that production can and will be raised by at least 50 per cent within the next decade." Drift had been largely controlled and cereal and sheep production were increasing rapidly. Land values doubled in some areas between 1962 and 1966. [Potter et a/. 1973,104]
TABLE 4.2. Soil Erosion and Land Clearance in the South Australian Murray Mallee, 1970s
|A. Soil Erosion|
|Total area in use||1,858.7||100|
|1) Area susceptible to erosion||405.3||21.8|
|2) Area where urgent and drastictreatment is required||20.0||1.1|
|Total Area||Area Cleared of|
|B. Land Clearance|
|1) Murray Mallee Study Area:|
|2) South Australia:|
|State Area||98,438.1||( 11,744.7)||(12)|
a. Williams 1978.
b. S.A.I.D.C. 1976.
c. The S.A.I.D.C. 1976 report only covered the area within the proclaimed hundreds l= 16% of state), which is the main settled area of the state. Hence the figures for clearance for State Area are estimates.
Such enthusiasm led to further clearance of mallee under government scrub-clearance subsidies and a temporary reversal of the decline in cropped area (Fig. 4.3).
The enthusiasm, however, was to be short-lived. Droughts in 1966-67 and 1970-71, together with government quotas on wheat production from 1969 to 1972 and falling prices for grains and wool in the early 1970s, renewed fears of a depression, and dust storms gave evidence of renewed desertification.
By the end of the 1970s the future of the area was again in doubt. Wind erosion was active, and while urgent soil conservation measures were needed on only cat 1 per cent of the South Australian area, a fifth of the area (ca. 22 per cent) was likely to erode if farm management was neglected (Table 4.2) and concern over illegal clearance of areas supposedly reserved (because of the erosion potential) had led to proposals to tighten up existing soil conservation legislation (S.A.I.D.C. 1976, 24).
In South Australia, as part of a policy of decentralization, the Department of Agriculture and Fisheries has begun to review the research needs of the state's primary industries. Significantly the first of such reviews was on the Murray Mallee (Fawcett 1978). In Victoria, the Land Conservation Council (set up in 1970 to advise the State Minister of Lands on appropriate use of Crown lands) has just completed revision of an earlier report on the Mallee area in which the problems of indiscriminate land clearance were outlined (V.L.C.C. 1976). Official concern and action continues, therefore, despite the earlier belief that the problems of the area had been met.
Research Method and Study Sites
To attempt to understand the role, if any, of human perception of resource management in the continued threat of desertification in the Mallee, the results of a recently completed field study of local attitudes to resource management were reexamined in association with archival search of recent official decision-making, media coverage of conditions in the area, and interviews with relevant officials. Because of the complexity of the definition of desertification, the surrogate of "soil erosion" was used here as in chapter 3. Thus attitudes and actions with regard to soil erosion have been culled from a variety of sources for consideration here.
The original field study involved interviews with 263 farmers and 31 non-farmers living in the area, in four separate sites chosen to provide a spectrum of drought risk and including areas in both states (Table 4.1). Thus the environmental gradient and possible political contrasts in land settlement and management policies were seen as variables. The field questionnaire, based upon that used in the international natural hazards studies (White 1974, 6-101,was designed to allow variables such as education, family responsibility, and experience on farm to be tested in relation to attitudes on resource management.
The detailed physical characteristics of the four sites are illustrated in Figs. 4.4 and 4.5 and Table 4.3. Although the general comments on the Murray Mallee apply, the history of land settlement of each site varies in detail. The Pinnaroo site was surveyed for agriculture in 1904 with additions to the south in the 1920s, the railway arrived in 1906, and agricultural occupation was mainly completed by 1914. The Murrayville site was surveyed and occupied soon after 1906, the railway from Ouyen arrived in 1908, and again most farms were occupied by 1914. The northern sites were developed later. The Paruna site was occupied partially by settlers from the Murray River after 1906, but most farms date from the arrival of the railway in 1914. The Millewa site was the last to be occupied, the railway from Redcliffs reaching Werrimull by 1923 and Morkalla by 1925. Because of inadequate groundwater here, a costly and grossly inefficient system of irrigation channels had to be dug to bring River Murray water during the winter months to fill domestic and stockwater storages for the summer.
By the 1960 the family farms were still dominant (79-91 per cent of the total) and ranged in size from 400 to 1300 ha. Of the original vegetation less than 20 per cent remained on the farms. South Australian farms had a higher proportion of land in improved grazing ((lucerne, clovers, and sown grasses) than Victorian farms (45 per cent of their area compared to 9 per cent) and a correspondingly smaller area in grain crops (13 per cent and 30 per cent, respectively). Surprisingly, the area in fallow was still significant in Victoria (21 per cent) compared with South Australia (3 per cent). More livestock were carried in South Australia (an average of 1,700 sheep compared with 400 in Victoria) and incomes varied accordingly.
FIG. 4.4. Land Systems of the Fieid Survey Sites, Murray Mallee
FIG. 4.5. Cross-sections of Field Survey Sites, Murray Mailee
Source: Laut 1977b; Rowan and Downes 1963.
Grain crops provided 82 per cent of income in Victoria, with only 7 per cent from wool, whereas in South Australia the figures were 40 per cent and 42 per cent, respectively.
Before examining the perceptions of desertification in the Murray Mallee, however, it will be useful to identify the various "interested parties"-those people or institutions who had some potential motive for concern about the problem.
Characteristics of the Perceivers
The Role of Governments
Because the history of land settlement in Australia from the 1850s onwards has reflected fluctuating but always significant official land settlement policies, the governments' perceptions of the land resources have influenced actual resource use. This influence has been stronger than that in the United States and has shown greater variation because
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