| Arid Zone Settlement in Australia: A Focus on Alice Springs (1985) |
2. Ecological setting and urbanization processes
In this chapter we first briefly describe certain aspects of site, climate, and water supply and demand as elements of the ecological setting of Alice Springs. These aspects of the essential settlement context will enhance understanding of the studies of attitudes to living in Alice Springs, life-style, migration, and service provision. The second part of the chapter introduces some discussion of the relations between urbanization, remote location, and arid ecosystems, arguing that there is conflict between them and that the dominance of the humid, coastal urban systems is itself an integral component of the settlement-arid zone ecosystem in Australia.
Site, Climate, and Water
Figure 2.1 displays some of the principal site features of Alice Springs. The dominant topographic elements of the ecological setting are the Macdonnell Ranges to the south of the township, rising to a height of about 800 metres, and the Todd River, which passes through the range at Heavitree Gap. This pass enables the only road and rail link into the town from the south. The Macdonnell Ranges are a severe barrier to southward expansion of the town, but they are also a very important element in the human ecology of the settlement, influencing aesthetic evaluation of landscape and townscape, local recreation, and intra- and international tourism. Plate 2.1 illustrates the view, north to south through Heavitree Gap, over Alice Springs, involving a distance of about 4 km.
The local climate is a significant element in the ecological setting because of its impact on water supply and as a determinant of human activity, especially tourism seasonality, focused on the winter months of June through September.
The Bureau of Meteorology (Alice Springs District Station provided the following general synopsis (mimeo) of local climate and weather.
The southern districts of the Territory have a land climate which is marked by cool and dry conditions during the winter with less than about 12 mm of rain per month during July, August and September.
At Alice Springs the average monthly rainfall increases during the summer to a maximum fall of 36 mm in February. Temperatures in Alice Springs vary between an average daily maximum of 19.5°C in July to 36°C in January.
The winter is marked by occasional dust storms which extend to Central and even Northern districts. Alice Springs districts experience to a lesser degree the frontal passages that are so prominent in the southern coastal districts of Australia. Temperature falls of ten degrees or more have occurred when a pre-frontal NW flow was replaced by a southerly airflow behind the front. These frontal passages are often accompanied by showers and thunderstorms and local dust caused by the forceful down-drafts from the thunderstorms.
TABLE 2.1. Seven or More Consecutive Days with Maximum Temperature at Al ice Springs > 100° F
|Dec. 1941||16||Jan. 1961||7|
|Jan./Feb. 1951||10||Jan. 1967||8|
|Feb./Mar. 1951||11||Jan./Feb. 1968||9|
|Jan. 1957||13||Dec. 1972/Jan. 1973||19|
|Dec. 1957||8||Jan. 1978||7|
|Mean= 10.28||Mean= 10.06|
Temperatures above 110.2° F are recorded in most years.
Consecutive days with a maximum temperature of 100° (F), for seven or more days are shown in table 2.1, provided by the meteorology station at Alice Springs. Mean maximum and minimum temperatures for the 27-year period 1926 to 1953 and the 34-year period 1940 to 1974 are graphed in figure 2.2.
Rainfall records in millimetres recorded at the Alice Springs meteorology office between 1941 and 1980 are illustrated in figure 2.3. The monthly variability of rainfall, number of rain days, highest and lowest monthly figures, and highest 24-hour falls, which indicate intensity of rainfall, are shown in table 2.2. The data are from unpublished records held at the Alice Springs station of the Bureau of Meteorology from 1874 to 1978. Long-term temperature and rainfall regimes combined with physiographic, lithographic soil characteristics and evaporation rates determine the water availability characteristics of the Alice Springs district.
TABLE 2.2. Rainfall: Alice Springs District (millimetres)
Nil several years
|Highest 24-hr fall||106.7||105.4||166.4||72.0||43.9||70.6||55.1||68.6||47.2||48.5||67.6||118.4|
The Town Basin, an area of unconsolidated sands under the town, was the principal source of water supply until 1965. Recharge of this basin depended on the Todd River, flowing north-south on the eastern perimeter of the town.
Annual water consumption in 1979, when the estimated permanently resident population stood at 17,000, was 6.6 million kilolitres, a volume 10 times greater than the maximum safe yield of the Town Basin of 600,000 kilolitres. Because of public health and management demands, this water is now only used for lawns, public recreation, and sporting areas. The current source of the town water supply is the Mereenie Sandstone, a part of the Amadeus Basin. The Mereenie bores are located 15 km to the south of Heavitree Gap. There were 21 production bores in 1979, and the modal depth is between 200 and 300 metres. The best bore pumps about 90 litres a second, and pumping occurs at a depth of about 130 metres below ground level. Natural recharge of the Mereenie Sandstone and related geological formations occurs over a region of 10,000 km² "Quite apart from recharge, there is sufficient existing water stored in the basin to last Alice Springs for hundreds of years. Nevertheless, as the population grows, development of the basin will become increasingly expensive. This is because the need to harness the available storage and recharge will require increasingly deeper bores and/or larger pipelines." (Report supplied by T.J. Verhoeven, Engineer, Department of Transport and Works, Northern Territory, 1979.)
Average daily consumption per person in 1979 was 1,100 litres. This is a volume greater than 400 cubic metres per person per year. Peak daily consumption in 1979 was 2,300 litres for every man, woman, and child in Alice Springs. This consumption level is similar to or greater than that in Australia's capital cities.
Water charges in 1979 to Alice Springs residents were A$75.00 per annum with a basic allowance of 750 kl. Excess charges were A$0.18 per kilolitre for 1 to 1,000 kl excess and A$0.225 per kilolitre for greater than 1,000 kl excess. Equivalent figures for the industrial city of Newcastle, on the Pacific coast of New South Wales, with a population of about 160,000 people in 1979/80 was 30.67 million kl of metered consumption. This gives an approximate per capita consumption of around 2,000 litres per person, but it includes some of the heaviest industries in Australia, including steel and shipbuilding. Charge are A$81.50 basic, which allows 395 kl at 20.59 units per kilolitre before excess charges apply.
Table 2.3 shows projected annual consumption assuming a 4 per cent population increase, with base year 1976.
Verhoeven et al. (1977) have proposed a water management policy for Alice Springs, and suggested policy implementation would include:
(a) declaration of a Water Control District around the Alice Springs environs to provide the necessary frame work for effective management;
(b) management of the present and proposed borefields in the Mereenie Sandstone;
(c) development of the limited ground-water resources lying between the present borefield and the town;
(d) management of the currently under-used town and farm basins to provide for watering of recreational areas and market gardens;
(e) utilization of reclaimed water for irrigation;
(f) investigation of the viability of surface water storage(s) which could be used in conjunction with ground-water resources;
(g) education of the local population on the need to conserve water;
(h) review of water metering practices and pricing schemes
Figure 2.4 (MacQueen 1980, mimeo) illustrates the principal water resource structure of the Alice Springs region
In a paper to the Australian Water Resources Commission in 1980, MacQueen reported as follows on his study of a part of the Amadeus Basin:
Recent ground-water investigations of 10,000 km² of the northern part of the Basin (MacQueen et al. 1980) have obtained considerable data on the regional flow and water quality pattern.
The available evidence indicates that the majority of regional recharge takes place over the fractured sandstone and limestone outcrops which comprise the margins of the various synclines, and emanates directly from rainfall or from small streams. The recharge resulting from the rivers appears to be much less, judging by the general lack of distortion of the potentiometric surface caused by the rivers. Recharge monitored at one gorge on the Hugh River was shortlived and probably local in extent.
Total annual recharge of the study region is estimated to be in excess of 100 x 106m³, compared with present pumping extractions of 7 x 106m³. This implies that some 10 per cent of rainfall occurring over outcrop recharges the Basin. It also implies a storage/flow ratio of about 10,000.
TABLE 2.3. Predicted Annual Consumption for Four Per Cent Population Increase, Alice Springs
(approx. 4% increase)
Source: Verhoeven 1979,
Apart from its principal use as a life-support agent, water is also very much a part of the life-style and the expectation of most Australians. The coastal cities are the source of most of the inmigration (chapters 4 and 5), and consequently water-related recreation, both passive and active is a very important component of life-style. In Alice Springs the absence of a permanent surface of water is a serious source of discontent among residents (chapter 4). The Department of Transport and Works has prepared a proposal for constructing a lake, 92 ha in area, about 3 km north and east of the township. The total cost was estimated at A$2.1 million in February 1980, at the time of a public meeting to assess the proposal. The maximum area of 92 ha would occur about three times per year when the dam was full. For at least 90 per cent of the time a lake in excess of 60 ha would be available. While recreation activities would be emphasized, a water supply of 1 million kl per year could be drawn from the lake and used to irrigate parks and gardens in the town, thereby effecting substantial savings on the Mereenie Basin and also overcoming the high salinity problems in the Town Basin. Reduced flow volumes of the Todd River would also help to alleviate serious problems associated with the high water table in the Town Basin, which has caused severe difficulties in construction of larger buildings. A conservative estimate of the life of the lake would be about 120 years, before siltation became too high to allow further recreational use.
Urban Process and Remote Arid Setting
Within the extensive, fragile, slow but easily perturbed dynamic of the Australian arid zone ecosystem there has been a lot of human activity in recent years, and it has created concentrated pockets of urban settlements. The precise location of many of these settlements is closely related to the distribution of mineral ores. In the case of Alice Springs, however, communication and transportation services have been the chief locational factors in both the initial and in the continuing growth of the settlement.
Exceptional circumstances apart, world-wide experience in regard to the effects of urbanization over the past two centuries has been one of growth. This is a common characteristic of urban systems but it has not been a common feature of isolated, traditional systems. With growth, modern urban communities consume increasing quantities of space and demand ever more time for consumption of the goods and services that they produce (tinder 1970), and there appears to be no limit to their territorial or population size.
An important component in any urban growth process is the characteristic of accessibility. The terms centrality and accessibility may be used interchangeably when discussing settlement systems.
Thus accessibility is a second common characteristic of all urban centres. Together these characteristics of growth and centrality induce the organization of the population into a social, economic, and political system of interdependent and often highly specialized units or components. This organization of the population, or display of predictable relationships, enables specialized roles to be performed and as a consequence provides a basis for a wide range of alternative activities to occur. These activities satisfy obligatory physiological needs as well as discretionary wants. The greater the scope for interaction among the specialized groups that is therefore induced, the more urban the settlement and the greater its potential accessibility. The consequence is more growth.
Organization is a third common characteristic of urban places, for instance, as family, firm, or other institution. If enables planning for future behaviour, and this leads to a fourth compound characteristic of urban places, common to all ecosystems-that of persistence and recurrence (Winterhalder 1980, Parkes and Thrift 1979). This last feature is a rather new one in the Australian arid zone, in particular in relation to persistent occupation of the same territory at increasingly high rates of behaviour recurrence. It may well prove to be the one most in need of study and of innovative resource management strategies. This property of persistence means that the various relations within the settlement must be much the same tomorrow as they were today, and yet, paradoxically, perhaps they must be conducive to the initiation of change as well as to the reception of inputs from outside. In ecological terms they must have adaptive capability, and if territorial scale of arid zone settlements is to be contained in order to minimize desertification of the containing region, management will have to develop coping strategies in other domains, including the timing of activities and new developments.
In order to attract people to central Australia and to hold them there, it will be necessary to find ways and means of capitalizing on the properties of accessibility, to satisfy the contemporary urban citizen's expectations. These expectations will be high. There is probably an inverse relationship between the expectations of the new settlers and their length of settlement in the centre: the more urban the expectations, the shorter the stay. The expectations will be much the same as those in coastal and buffer zone Australia (Parkes 1975) because it is from the coastal cities that most of the labour force will be drawn. Increasingly this will be a labour force that must be able to synchronize with rather advanced technologies. The need therefore arises for understanding how, when, where, and for how long people and the tools which are products of modern technologies will have to be synchronized (Hägerstrand 1974), because this will indicate whether or not reasonable expectations can be satisfied.
The most likely situation is that many positive expectations will not be satisfied. Residence is likely to be temporary. Thus, while there might be growth in population numbers, social organizations may be inadequate to facilitate participation in a wide range of activities. The necessary urban properties of persistence and recurrence within change will not be present because there is likely to be insufficient continuity in the composition of formal and informal groups. But it is through the known timing and regularity of meetings and functions associated with groups of all types (schools, tennis clubs, political clubs, and retail and work times, etc.) that an important component in the sense of community develops. The sociologist Gurvitch (1964) considered the timing characteristics of groups to be so important a factor in the structure of a human ecosystem that he advocated that the timing pattern of the activities involved should also be used as a basis for classifying groups and assessing their rote in community formation and survival.
So, centrality (or accessibility) is at the core of every viable urban place. Because of the property of centrality, urban places are able to offer a wider range of goods and services; they are able to satisfy more of the needs and wants of a regional population. The map of Royal Flying Doctor medical services (fig. 2.5) illustrates the geographical centrality of a number of settlements in the arid zone.
But territorial centrality alone is not sufficient. The timing of service provision, whether commercial (as in retailing) or social (as in hospital services, for instance) must also be central to the needs and wants of the population. Unlike territorial centrality, temporal centrality has greater potential for management. It is often easier to re-time services and to have variable times for the same service category, satisfying the needs of different categories of the population living in a settlement such as Alice Springs, than it is to relocate or duplicate the service in different areas of the town.
Alice Springs has many of the properties necessary to enable a high degree of centrality to develop. However, relatively high growth potential that results from high centrality qualities may not be realized or achieved without appropriate management of utilities such as water and other energy. The properties of urbanization and its associated behaviours (or urbanism) demands appropriate utility management. Unmanaged or illmanaged urbanization, as towards population growth at any price, will have impacts on the arid environs which are probably irreversible in any socially or politically acceptable time period. The ecological time period, which is determined by the dynamic of the encompassing natural ecosystem, is long for arid regions because the dynamic is slow-apart from the intermittent occasions when there is rapid response to "good rains."
Three related rubrics can be stated as:
1. The dynamics of the arid zone are slow, and the period of most cycles is therefore long.
2. The dynamics of urban places are fast, and the period of most cycles is therefore short.
3. The management task is to maintain the "cohesion" or phase relations between the two systems.
The arid and semi-arid environment is therefore also more susceptible to system disruption than the relatively robust humid environments in which most Australian settlement is located, and "because so much of Australia lies in the difficult arid and seasonally dry tropical zones . . . there is need to assess the land in its natural state and to appraise and adjust to a physical environment which poses problems because traditions have been brought in from temperate regions [overseas]'' (Mabbutt 1972). Furthermore, because so much of the decision-making related to capital investment, labour movement, transport scheduling, and route paths and qualities is made in the less susceptible. humid coastal fringe, there is likely to be an insufficient awareness of the full implications or consequences of some decisions.
The invasion process is familiar to plant and animal ecologists but operates also for humans and for their material/ non-material traits, as when new artefacts and information invade the arid zone due to migration and modern communication channels. This latter medium is a component of the cybernetic revolution referred to in the introduction. The invading artefacts and information include residential subdivision practices and house types, work time practices, school terms and timetables, recreation habits, and other tesserae of the "stream or biography of urban life," which are not necessarily adaptable to the arid zone ecosystem.
If ecologically harmonious settlement-environment relations are to be established in the arid zone, then passive design building, activity time-management schemes, and nationwide educational programmes will help to avoid increased desertification on the one hand and the growth of inefficient, unstable urban places on the other, such as a scatter of short-lived mining towns and hedonopolistic resorts for urbanites from the coast with little or no interest in the long-term future of either the settlement or the arid zone.
The urbanization of central Australia has little in common with either the contemporary urbanization process in the high population potential regions of the North American arid zone or with urbanization in many of the world's other arid regions where there was already a substantial tradition of desert-living in villages or towns; some indeed are viewed as the cradle of nascent urbanization. Nor do the present-day urban settlements of central Australia have anything in common with the traditional Aboriginal ways and means of living in that region before white colonization. But there is much to be learned from certain aspects of habitation of both the traditional Australian and the traditional desert people of other parts of the world. With the latter this is especially the case in relation to high mass, low-energy-demanding building designs. As for the traditional Australian desert people, as Meggitt (1962) has called them, the most significant principle for man-environment adaptation is probably periodic use.
The principle of periodic use recognizes the limited carrying or packing capacity of the arid zone. The nomadic desert people evolved management systems to cope with an environment which they were apparently not forced to use. They scheduled and rostered their use of arid space, they appraised it as a scarce resource and fear of lack of space was very real, despite the fact that "density of occupation was about 1 person per 35 square miles" (Meggitt 1962, p. 32) among, for instance, the 1,200 strong Walbiri tribe (estimated by Meggitt 1962). The Walbiri people occupied the region north of what is now Alice Springs but also extending west to Haasts Bluff and northwest to Yuendemu, Tanami, Hooker Creek, and Victoria River.
While the Aboriginal people of the Australian arid zone did not practice the sort of complex space-time transhumance of the Basseri and other tribes in Persia (Iran) described by Barth (1959), there is evidence that the Dieri people used strict controls on where and when certain activities could occur (Gale 1978). This space and time management of the arid environment allowed the Aboriginal people a distribution over Australia which was much less spatially biased towards the easier environments of the humid east coast.
Today, in the same natural environment, we treat space as limitless. The fear, dislike, or constraint is of too much; distance is a tyrant to be overcome; use is dense and intense; and for maximal capital return it should be used around the clock.
The paradox that space is a scarce resource in the Australian arid zone of 5.7 million km² is resolved if it is understood that space has no inherent value as a resource, but must always be related to the total population supply and demand for time. If the time supply of a population is too high or if population time demand is too great, even the vast Australian outback will not be big enough when there is a marked focus on particular zones. Tourist behaviour, considered later, appears most likely to reveal the validity of this viewpoint.
Therefore, when activities are available for participation is as important as where they are available. Whether certain activities occur at all may depend on scarcity of time to attract sufficient interest just as it may depend on scarcity of space. Effective demand for an activity means that there is sufficient population time supply. The time and space resources for any settlement must therefore be appraised in relation to the demographic and social characteristics of the population. The supply varies in its distribution in direct response to the demographic and socio-economic structure of the resident population.
Residents however should be considered, in the strictest sense, as including all persons who spend "sleep-time" in the settlement. Thus, in a town such as Alice Springs, which is increasingly reliant on tourists for its basic income, hotelmotel accommodation is residential, and to the extent that there is a seasonal rhythm to the tourist industry, there is a variable time supply-space supply ratio. This already complex condition is further complicated by the demographic and socioeconomic variability of the tourist population. This variable population time supply exerts a differential impact on the settlement setting or environment. Alice Springs, for instance, acts as the reception area for a contemporary "desert nomadism" to Ayers Rock, the Olgas, and the Peterson Ranges, 500 km away. The settlement of Alice Springs becomes a pacemaker (Parkes and Thrift 1979, 1980) for a spatially remote, ecologically unique, and highly susceptible desert ecosystem, which even in its present nascent urban phase must also include the road or highway chain linking the source (Alice Springs) and destination (Ayers Rock). By way of example we would argue that control or management of the desert environment of Ayers Rock or of the many beautiful gaps and gorges along the 400 km of the Macdonnell Ranges must begin at the central, urban reception points, which provide most of the access to the tourist destinations. Every urban centre poses a threat to the arid zone ecosystem through its pattern of urban activities, few more so than tourism, because urban dynamics are not likely to be ecologically coherent with the dynamics of an arid zone ecosystem unless there is strategic, rational intervention. The high densities at which modern technologies allow human settlement to be sustained are a major part of this condition. Once again the population-containing dimensions of space and time hold the key to appropriate management programmes.
No longer does the arid centre operate as an independent or closed ecosystem, as it probably did when the pre-European Aboriginal people moved cautiously about the space, staying at one location only as long as the environment could support them, leaving sufficient "information" for the desert environment to re-establish itself before the next contact. The distant, large, metropolitan centres of Australia are the source of most of the social, political, work-related, and material innovations that are rapidly diffused through communication and transport networks with little regard for the susceptibility of the adopting target system to consequent severe perturbation due to "entrainment to the cycles and other tempos of an urbanising world" (Parkes and Thrift 1979). Adoption or rejection of these innovations, which may be mere "fashions" in the socio-political urban system, can have important repercussions for the receiving settlements. For instance, any abrupt change in transport circumstances, e.g., fuel pricing, fare structures, and technical innovations such as wide-bodied high-passenger-load aircraft, would be initiated in the coastal capital cities, perhaps even overseas and transmitted to the Centre, where reception may be economically good but possibly only in the short term. The management task is to ensure long-term growth, timely access, highly integrated social organization, and system structure persistence and recurrence, but not necessarily without managed interruption. Without appropriate space and time management the long-term consequences of certain innovations for the arid zone environment may well be irreversible. One cause will have been a time frame for an event frequency and scale which was not in phase with the arid zone system. Just as we are able to think of the space and time demands of people, so too do the elements in the big-physical environment have their own space and time demands, set within an ecosystem of constraints. The importance of appropriately matched time scales in human ecological research has recently been stressed by Winterhalder (1980, p.157); he cites Wiens (1977, p. 592) as an example explicitly concerned with "continental arid and semi arid regions."
Literally and figuratively, an oasis is a fertile spot in the desert. Wilson has suggested the term "oasisification" in a discussion of the impact of urbanization on the Sonoran Desert of Arizona (Wilson 1976, p.173). Through application of ecologically compatible design, urban places can indeed be oases, but the symbiotic relation must be managed as one that is able to persist and its system relations to recur possibly for hundreds of years, but which is also able to adapt to exogenous change without imposing an unpredictable and therefore a weakly controllable impact on the ecosystem.
We no longer question the fact that range-land animal stock numbers and their movements should be controlled. The urban dweller or short-term visitor is not such a markedly different animal. Here, too, there must be control, unless of course there is no concern at all that humans might aggravate the already rapid extension of desertification.
With appropriate management of this "unnatural" alliance between sedentary man, occupying settlements at densities which are literally hundreds of times greater than those set by the pre-European Aboriginal people in the arid and desert environments of central Australia, there can be a bright urban future for desert settlements, as Petrov argued some years ago, in a general context. "Future desert inhabitants will be able to take advantage of all the achievements of technology, contemporary as well as future . . . The rather high outlay for equipping such settlements will be fully warranted because there are so many diverse and abundant valuable resources in deserts that part of the profit from their exploitation could and should go toward improving the living conditions of those who create this wealth" (Petrov 1976, p. 408). This last point is an important one because at present everything that happens in the centre of Australia happens there because of the demands of the coastal urban systems and of the urban world to which those systems are tied; tied indeed as closely as is any suburb to its city or urban centre. Appropriate returns must be made to the arid zone, to the settlers, and to their settlements. If this does not occur, then at some time in the not-too-distant future it will be necessary to re-phrase Mabbutt's description of desert (1978, p.113) cited at the start of chapter 1 in this volume as, "In its sense of desolate and uninhabitable, a desert expresses man's ignorance."