The Oodnadatta Track – String of Springs
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Water and Plants The OOdnadaTTa Track – String of Springs Take this brochure with you as you drive along the Oodnadatta Track Stop and look at the many different plants and trees along the Track Find out how the watercourses and springs which you come across are linked to Australia’s two great inland water systems – the Great Artesian Basin and the Lake Eyre Basin 01 The Oodnadatta Track The Great artesian Basin When white pioneers set out to explore Australia’s interior, they thought they would find an ‘inland sea’. As it turns out, they were only partly wrong. Early explorers were devastated to find an apparently ‘impassable’ horseshoe of salt lakes. But beneath the surface lay an ancient water source that now sustains wildlife; a significant pastoral industry; a strong mining operation at Olympic Dam; Australia’s largest The Oodnadatta Track inland oil and gas field, the Cooper Basin; and of course, a thriving tourism industry. Visitors to the Oodnadatta Track The Great Artesian Basin (GAB) is one of the might think that they are journeying world’s largest underground water reservoirs, with an estimated 64,900 million megalitres of over waterless plains. But beneath water in storage. Underlying 22% of Australia, them lies one of the world’s largest the Basin formed between 100 and 250 million aquifers, the Great artesian Basin. years ago. Water enters the Basin in ‘intake beds’ on the And it is along the edges of the Oodnadatta Track western edge of the Great Dividing Range on that the Basin squeezes to the surface, creating dalhousie Springs Australia’s east coast, and slowly flows downwards oases of springs and attracting birds, wildlife, at an average of less than three metres a industry and tourists. a typical mound spring year. It is estimated that water currently coming out at the south western limit of the There’s not much rain – it varies from around GAB is around two million years old. 180 mm (7 inches) a year in the northern parts of the The Oodnadatta Track lies on the western Track to around 115 mm (41/2 inches) in the south. margins of the Great Artesian Basin. Temperatures can be high, sometimes reaching up In many places the Basin water has to 50°C in summer. squeezed to the surface in the form of Rainfall patterns are largely cyclical, ranging from natural springs. Many of the GAB springs years of dry to heavy flood events. In wet times, are known as ‘mound springs’ because of plants flourish and animal numbers boom. In dry the characteristic mounds associated with them. The mounds have been formed by times, this country is lean and all life keeps a low mineralised material coming to the surface with profile. In these times, vegetation and wildlife the ancient water. You can also see extinct mound concentrate around refuges, such as waterholes springs along the track, most notably at Hamilton and mound springs. Hill and Beresford. The Oodnadatta Track crosses the traditional lands There are more than 1,700 individual springs in 23 of three Aboriginal groups. In the south, between complexes found within the South Australian part Lake Torrens and Lake Eyre are the Kuyani people; of the GAB. The largest group is the Dalhousie most of the west of Lake Eyre has been traditionally Sleepy Lizard tracks in the sand complex, where more than 60 springs are located. occupied by the Arabana people; and to the north is Most springs in fact are not ‘moundsprings’ but the land of Arrernte people. Now many people from • The string of springs following the Track made it small inconspicuous soaks in the ground. The further west, Antikirinya people, live there too. possible for John McDouall Stuart to complete water of the GAB is generally alkaline and saline with high concentrations of dissolved solids such the first crossing of Australia’s interior from A string of springs runs right through this country. as carbonates, sulphates and chlorides. Knowledge of these springs has been passed south to north in 1862; Many springs have great significance for local • The overland telegraph was constructed along down through generations of Aboriginal people Aboriginals whose ancestors relied on them as since ancient times. It was a path that was well this pathway, linking Australia to the world for watering points and as sacred sites for important travelled whether for cultural ceremonies or trading the first time; ceremonies. There are many Dreamtime stories purposes. And the Aboriginal people passed their • This was the route of the Great Northern Railway, associated with the springs, such as the story knowledge on to explorers and settlers. which made the land of the Northern Territory behind the ‘Bubbler’ related on the map overleaf. Indigenous tourism services operate from Marree ‘It isn’t the straightest route, but it’s the only one if accessible for white settlement; for those wanting to find out more. you want to survive’ • And this is pastoral country, where Sidney Emerald Springs, and Blanche Cup were the first The Track has many stories to tell. And water is at Kidman and others developed their leases such GAB springs to be located by white explorers. the heart of all of them. as Anna Creek Station. This opened the way for European settlement and • This is the path of ancient Aboriginal trade All of this has only been possible because of the by 1859 the first pastoral leases were established routes, where traders hopped from one spring waters of the Great Artesian Basin that come to in this region. to another, carrying materials from the Flinders the surface along the Track, creating the ‘string of You are also now part of that story! Ranges deep into central Australia and back; springs’. 1 Plants ground is warm. It is also programmed not to Good rains that can fall at any time germinate in the same area in two consecutive of the year change everything along years even when the rainfall is apparently adequate the string of springs. and seed is in the ground Temperature affects germination. Bladder saltbush In late autumn and winter they turn enormous will not germinate above a certain temperature to stretches of countryside into spectacular regal birdflower avoid “cooking” in the heat. Timing can be very landscapes of colour. Dunes and sandy plains Kutsche Werner specific. For instance you’ll see button grass, a might be covered in carpets of numerous varieties favourite of the budgerigars, following rains during of annual flowers – yellow, white and pink daisies, February, when optimum ground temperatures and the spectacular regal birdflower or blue cattle bush. rainfall are likely to coincide. Summer rains can produce brilliant spreads of Sturt Seeds can remain dormant in the ground protected desert pea and Swainsona peas of orange, white, Poached-egg by their tough outer coverings for many years until daisies. They will pink and purple hues. flower for months the right conditions return to trigger germination. Check out the roadside in good years specials! Showy groundsel, how plants survive one of the larger yellow Dry times are a normal part of the climate cycle out Senecio daisy bushes, here and most plants are drought evading. makes an unexpected Drought-resistant perennials are present all the Frankenia. splash of colour along time. Tall shrubs and trees maximise their access a hardy sea-heath. Look for it on drainage lines and in the to water by a combination of shallow roots to sandy patches of road gibber plains and capitalise on light rains, and a deep tap root system around salt pans verges alongside lush to reach the deeper reservoirs of moisture. and mound springs stands of the purple verbine In exceptionally dry times most arid perennial plants native hollyhock and pink native hollyhock. abundance of the fleshy-leaved plants munyeroo will cease growing. Some partially or completely and native spinach (also known as New Zealand shed leaves to preserve nutrients and energy. Why is there such a wonderful spinach). These are particularly useful because variety of plants out here? chenopod shrubland on a diet of these moisture-laden plants stock can Climate, landforms and soil types determine where Chenopod shrublands are plant communities spend extended periods of time away from their and when plants will grow. largely from the family Chenopodiaceae. It includes watering points. Early white settlers used to eat The climate in this country is erratic. So, to survive, saltbush (Atriplex), bluebush (Maireana), samphire them as well. plants have evolved in many different ways. Soil (Halosarcia – Sclerostegia) species and bindyi In drier times cattle graze on nearly all of the types vary – ranging from clays to sandy loams; (Sclerolaena) and buckbush, better known as roly Chenopods with the exception of the samphires. from sand plains to limestone and saline soils; poly or tumbleweed (Salsola kali). Much of the But a diet high in saltbush requires a supply of from alluvial soils associated with swamps and low vegetation you see along the Track is from this reasonable water to counteract the salt. watercourses to rocky ridges, hill slopes and hard family. They are all plants that have adapted to gibber country. All are habitats for different plants South Australian arid zone conditions. Why did so many pastoral where the distribution of nutrients varies greatly. settlements fail in the early days? What do livestock eat out here? Early white settlers along the string of springs Germination Stock have a greater choice of feed in pastoral were misled by the presence of permanent waters Plants out here can be quite particular about country than in the more settled areas.