The largest rivers in Australia. The longest rivers of Australia Rivers lakes of the sea of ​​Australia

Introduction

Relevance: the study of the relief, climate and hydrography of the mainland is relevant, since it makes it possible to examine the nature of Australia in more detail and carefully.

The Australian continent is one of the oldest land masses, the flattest of all continents and, apart from Antarctica, the driest. This is the smallest continent globe(7.6 million km2). Australia is washed by the Indian Ocean from the north, west and south, and by the Pacific Ocean from the east. In the north, archipelagos of islands and inland seas connect it with Southeast Asia. Off the southern coast is the mainland's largest island, Tasmania. The northeastern shores of the continent are washed by the Coral Sea. The entire central part of the southern coast is washed by the waters of the Great Australian Bight. The area of ​​the continent is 7.7 million km2.

Almost one-third of the continent's area, mostly inland, is desert or semi-desert, not occupied by agricultural land. 60% of the territory is drainless, only one large Murray-Darling system in the south-east of the country is used for shipping and irrigation.

Australia is poor in surface water, which is due to the dominance of dry tropical and sub-water on the mainland. tropical climate, the absence of high mountains with snow and glaciers. Of all the atmospheric moisture that falls in Australia, only 10-13% enters water bodies, the rest either evaporates or seeps into the soil and is consumed by plants. This is the main reason for the continent's exceptional poverty of surface water. Over the course of a year, only 350 km3 of water flows into the ocean from the entire area of ​​Australia (less than 1% of the total flow of the Earth’s rivers). The distribution of surface water across the continent is very uneven. More than half of the river flow comes from poorly developed areas north of the tropics. Australia has few rivers and lakes; about 60% of the continent does not flow into the ocean. No other continent has such a relatively large area of ​​internal drainage. The main part of the continent, especially its internal desert and semi-desert regions, is characterized by temporary drains - cries. Water appears in them only after rare rains and for a short time. The remaining rivers of the mainland belong to the basins of the Indian and Pacific oceans. The rivers of the Indian Ocean basin are short, shallow, and often dry up during the dry season. The Pacific Ocean basin includes rivers flowing from the eastern slopes of the Great Dividing Range. These rivers are full of water throughout the year, as there is a lot of rainfall here; short and rapids. Most rivers on the mainland are fed predominantly by rain, while in the Australian Alps it is mixed. There are about 800 lakes in Australia. Most of them are relict lakes, the basins of which were formed during wetter geological eras. Many of Australia's modern lakes are dry basins filled with loose clay-salt marsh silt and covered with a crust of salt or gypsum. They fill with water only after rare rainfalls, which occur once in Western Australia for several years. Against the backdrop of a sparse hydrographic network and almost complete absence freshwater lakes amazes Australia's amazing wealth of groundwater. The area of ​​all artesian basins occupies 1/3 of the continent's territory. More than 15 artesian basins are confined to the basement syneclises of the platform between the plateaus of Western Australia and the Great Dividing Range. The depth of groundwater is from 100 to 2100 m. Sometimes The groundwater under natural pressure they come to the surface in the form mineral springs. The largest groundwater reservoir in Australia is the Great Artesian Basin.

Purpose: to characterize hydrographic resources and show their impact on the nature of the Australian mainland.

1. study the literature on the topic of hydrography of Australia;

2. study the features of lakes and river systems in Australia;

3. show the influence of groundwater on the nature of the continent.

Object: Australian continent

Subject: hydrographic objects of the mainland

Research methods:

Statistical;

Research;

Cartographic.

Structure course work:

The introduction reveals the relevance, purpose, objectives, object, subject, as well as research methods of the course work.

The first chapter examines the geological structure and climatic conditions of the continent. The Australian platform has been subject to slow uplift, subsidence and faulting throughout the continent's geological history. The climate is dry and continental.

The second chapter reflects the features of the continent's hydrography. Approximately 10% of the territory drains into the Pacific Ocean, the rest belongs to the Indian Ocean basin. There are many lake basins in Australia, but all of them are currently deprived of water and have turned into salt marshes. Distinctive feature Australia is rich in groundwater. They accumulate in artesian basins occupying troughs of the ancient foundation along the edges of the Western Plateau and in the Central Lowland.

The conclusion summarizes the material of the two chapters, highlights the results of the research, and draws a conclusion on the entire course work.

Literature review: when writing my course work, I mainly used the following sources: Ed. Pashkanga K.V., Physical geography for preparatory departments of universities, M., 1995.; Korinskaya V.A., Dushina I.V., Shchenev V.A., Geography 7th grade, M., 1993; Vlasov T.V., Physical geography of continents, M., “Enlightenment”, 1976.-304 pp.; Pritula T. Yu., Physical geography of continents and oceans: textbook. higher allowance textbook institutions / T. Yu. Pritula, V. A. Eremina, A. N. Spryalin. – M.: Humanitarian. ed. VLADOS center, 2004. – 685 p.

1. Characteristics geological structure and climate of the Australian continent 1.1 History of formation, main features of the relief of Australia Australia is a very ancient continent. In the geological past, half of Australia was part of Gondwana, from which it separated towards the end of the Mesozoic. At the base of its western and central parts, covering ¾ of the total area, lies the Precambrian platform - part of the Indo-Australian lithospheric plate. The age of the crystalline rocks composing the platform in some areas reaches and exceeds 2.7 billion years. The crystalline foundation of the platform in the north, west and central part in some places comes to the surface, forming shields. In the rest of the territory it is covered by sedimentary rocks of continental and marine origin. The cover of sedimentary rocks reaches its greatest thickness in ancient troughs. Throughout the entire geological history of the continent, the Australian platform has been subject to slow uplifts, subsidences, and faults. Its surface has been destroyed by winds and waters for a long time, and now this continent, the flattest in the world, amazes with its amazing evenness and uniformity of relief. These features are especially noticeable within the Western Australian Plateau - the most ancient region of the continent. A significant part of the plateau reaches an altitude of 450 - 600 m, but along its edges a number of low mountain ranges and isolated flat-topped massifs rise above the monotonous rocky-gravelly or sandy surface - these are the remains of higher mountains of the past.

The geological structure of Australia is the simplest compared to other continents. It contains the Precambrian platform and the Hercynian fold belt. The Precambrian platform makes up 2/3 of the continent's Western Plateau and almost the entire Central Lowland. The western part of the platform represents the anteclise of the ancient basement, where Precambrian crystalline rocks and, to a lesser extent, Proterozoic and younger sedimentary formations are exposed. The eastern part of the syneclise platform of the ancient foundation. The Precambrian basement here is lowered and covered by a thickness of Mesozoic (mainly Cretaceous), Paleogene and Neogene marine and lacustrine sediments. Hercynian folded structures make up the eastern mountain belt of the continent. In addition to Paleozoic folded-sedimentary formations, volcanic and intrusive rocks of all ages take part in its structure. The Australian platform was subject to faulting and oscillatory movements that occurred in connection with tectonic movements in the geosynclines that framed it from the west and east. The Western Australian geosyncline, which formed in the Precambrian, was part of a huge geosynclinal zone that framed the Archean and Proterozoic land cores in the southern hemisphere. Lower Paleozoic folding and oscillatory movements that occurred in this zone created land connections between the Precambrian platforms of Australia, Southeast Asia and Africa, which were preserved in Paleozoic era and in the first half of the Mesozoic. The splits that led to Australia's separation from Africa and Southeast Asia occurred only in Cretaceous period. In the East Australian, or Tasmanian geosyncline, the Lower Paleozoic folding formed a mountainous country, which in the west adjoined the leveled Australian platform, and in the east went beyond the modern contours of the continent. However main role In the formation of the mountains, the Upper Paleozoic folding took place, as a result of which a huge section of the mountainous land of Tasmania, stretching in place of the Tasman and Coral Seas, was raised from under sea level. Since the end of the Paleozoic, Tasmania's landmass has experienced slow fluctuations; at the beginning of the Mesozoic, troughs captured the Central Lowland. They led to the transgression of the seas and to the formation of vast lake basins in which limestone and clayey-sandy strata were deposited. Seas and lakes have long isolated Australia's western flattened landmass from its eastern mountainous country. The general uplift of the continent at the end of the Cretaceous caused the retreat of the seas and the shallowing and drying out of lakes. The northern and eastern margins of the Precambrian structures of Australia and the Hercynian structures of Tasmania were framed by an Alpine geosyncline.

Tectonic movements in it led at the end of the Cretaceous to the loss of land connections with Southeast Asia and the New Zealand structures that survived the submersion. Powerful folding in the Alpine geosyncline occurred in the Neogene. The high mountains of New Guinea, New Zealand and the mountainous archipelagos of islands between them were erected. On the hard bases of Australia and Tasmania, folding was reflected by faults, movements of blocks along them, intrusions, volcanic activity, slow flexures and uplifts. The western fault edge of the continent rose; On the Tasman Land, the Kimberley horst massif outlined by faults stood out. The Flinders Lofty horst ranges were separated from the southwestern edge of the Western Plateau by the Lake Torrens graben. The most significant changes in topography, as well as in the size and shape of the continent, occurred in the east. Along fault lines, a significant part of Tasmania sank to the bottom of the Pacific Ocean, its western edge, preserved from immersion, rose high, which determined the orographic expression of the East Australian Mountains. Their ancient rocks were overlaid with basalt covers, which occupy especially large areas in the central and southern ranges. During the Quaternary period, the marginal parts of the continent continued to slowly fluctuate. The final separation of Tasmania and New Guinea from the mainland took place; the subsidence of individual mountainous sections of the coast created finely indented rias coasts on the island of Tasmania, in the northwest and in the east of the mainland. The nature of the relief of Australia is determined by the antiquity of its constituent structures and long-term peneplanation. The latter led to the leveling of vast territories, so that what is striking about the relief, first of all, is its amazing monotony: the continent is a plateau with an average height of 350 m, i.e. It is the lowest part of the land after Europe. From the previous ones more high levels Flat-topped island mountains (in places where sedimentary formations occur) and peaked massifs (in places where crystalline rocks occur) have been preserved. The largest area is occupied by the leveling surface created during the period from the end of the Cretaceous to the Neogene, the so-called Great Australian Peneplain. It has a height of 300-500 m on the Western Plateau, does not rise above 200 m in the Central Lowlands and rises to 700-1500 m in the East Australian Mountains, where it can be traced in the same levels of flat-topped massifs. The wide distribution and good preservation of planation surfaces and, in particular, the Australian peneplain, are explained by the slowness of vertical land movements and the weak degree of dissection of the relief in a predominantly desert climate, as well as the armoring effect of protective crusts.

Ferrous and siliceous protective crusts have been preserved mainly since the Neogene, when the necessary climatic conditions for their emergence were very hot and seasonally humid conditions. The formation of limestone, gypsum and sulfate protective crusts began at the end of the Neogene in a dry and hot climate and continues now in the interior of Australia. Short-term humidification and cooling during pluvial eras Quaternary period entailed the formation of erosional landforms ( river valleys, lake basins, etc.) preserved in modern desert areas. Glacial sculptural forms, as well as the relief of glacial accumulation, are characteristic only of the Australian Alps, the only region where, in addition to the island of Tasmania, there was Quaternary glaciation. Peculiarities tectonic structure Australia allows us to distinguish three structural and morphological provinces on the mainland: the Western Plateau, the Central Lowland and the East Australian Mountains. The western plateau, which generally coincides in its outline with the anteclise of the Precambrian basement, represents a weakly dissected surface of the Great Australian peneplain with an average height of 300-500 m. On its eastern edge rise the crystalline ridges of the MacDonnell and Musgrave ranges, prepared by denudation (Mount Widroff, 1594 m, the highest point of the Western Plateau). U western edge there are extensive flat-topped remnant massifs (Hamersley Ridge, etc.). The southwestern edge of the plateau, steeply falling to a narrow coastal lowland along the fault line, is called the Darling Ridge. In the north-west the plateau is framed by the Kimberley horst massif, in the north it ends on the Arnhem Land Peninsula. Huge areas in the interior are occupied by sandy and rocky deserts. Sandy deserts The Great Sandy and Great Victoria Deserts lie on the northern and southern slopes of the Western Plateau and are separated by the rocky Gibson Desert. In the southwest, lake basins have been preserved as evidence of the wet eras of the Quaternary period. In the south, the Nullarbor Karst Plain stands out. Central lowland. The prerequisite for its formation was the trough of the eastern margin of the ancient Australian platform, the subsidence of part of the Caledonian folded structure, as well as subsequent marine and lacustrine regimes. Thicknesses of marine and lake sediments hid the unevenness of the ancient relief, which appears only in the form of weakly expressed hills on the outskirts of the lowland. Its middle part, the so-called Central Basin, lies in the area of ​​Lake Eyre, 12 m below sea level. This is the lowest place in Australia. In the western half of the basin there are deserts that continue the desert belt of the Western Plateau.

The south-eastern part of the Central Lowlands is occupied by aggradational plains crossed by Australia's largest rivers, the Murray and Darling. In the lower reaches of the Murray, to the west of the river, the area of ​​the Flinders Lofty horst-block ridges stands out. East Australian Mountains. For a long time they were called the Australian Cordilleras, however, in terms of the type of relief they differ sharply from the Cordilleras of both North and South America. These are ancient (mostly Hercynian in age) horst-block mountains, already heavily destroyed, with average heights of about 1000 m, mostly flat-topped. Paleogene and Neogene faults and faults split them into separate ridges and massifs. Reset along east coast Australia determined the steepness of the eastern slopes; the gentler western slopes descend into the Central Lowlands in rolling foothills (downs). The outpourings of basalts that accompanied the splits left their mark on the shapes of the ridges in many places. Stepped plateaus are associated with linear eruptions, volcanic cones are associated with eruptions of the central type. In the highest mountain range, in the Australian Alps (Kosciuszko Peak 2234 m), traces of Quaternary glaciation have been preserved: cirques, troughs, glacial lakes. Karst is developed in the limestones that make up the peaks of the Blue Mountains and some others. Minerals. Due to the weak development of sedimentary covers, Australia is characterized by a significant predominance of ore minerals over nonmetallic ones. The areas of the most active metallogeny are concentrated along the western margin of the continent and in the southeast, in the contact zones of platform Precambrian and geosynclinal Paleozoic structures, as well as in the East Australian Mountains, in folded Caledonian and Hercynian structures. Australia has significant reserves of gold, non-ferrous metals and iron ores. The leading role among ore minerals is played by gold, the main deposits and mining areas of which are concentrated in the southwest of Western Australia (Kalgoorlie, Coolgardie, etc.), in the state of Victoria (Bendigo, Ballarat) and in the northeast of Queensland (Charters Towers to the south). -west of Townsville, etc.). The most significant area in terms of production and reserves is the southwest, covering vast areas in a wide strip between the Murchison River and the city of Dundas. Non-ferrous metal ores are concentrated mainly in eastern Australia. The largest deposit (and main mining area) of copper ore is located on the island of Tasmania (Mount Lyell); large deposits of copper ore are available and developed in Queensland (Mount Morgan, Mount Isa). Australia has very large reserves of polymetallic ores of zinc, lead and silver.

New South Wales ranks first in reserves and production of polymetallic ores. The state's Broken Hill deposit is one of the largest in the world. Significant amounts of silver and zinc are mined in the north-east of Australia in Queensland (Mount Isa), as well as on the island of Tasmania. It is also necessary to mention the very large reserves of tantalum and niobium, the industrial deposits of which are concentrated in Western Australia (Pilbarra). Deposits of uranium ore ores have been explored and exploited in South Australia (Mount Painter and Radium Hill) and in the Northern Territory (Rum Jungle, etc.). The main mining area for iron ore deposits is near Iron Knob in South Australia, although larger reserves than at Iron Knob are found on the islands of Coolen and Coatoo in Yampi Bay (north of the Fitzroy River mouth), as well as in the Murchison River basin. There is little or no mining in these areas at present due to the difficulty of transporting ore to the New South Wales smelters. In terms of coal reserves, Australia ranks first among the countries of the southern hemisphere. The largest coal basin (Permian age) is located in New South Wales and occupies a very advantageous geographical position, stretching in a strip of 250 km along the coast of the Tasman Sea. The thickest seams of high-quality coal are concentrated in the area of ​​the cities of Newcastle (mainly) and Sydney. The second largest basin is located in Queensland (in the Brisbane and Claremont areas). The coals of this basin are Permo-Carboniferous in age. Brown coals (Tertiary age) are mined by open pit mining in the state of Victoria, in the vicinity of Melbourne; There is information about the discovery of new reserves of brown coal off Adelaide. Oil exploration, which is currently being intensively carried out, has not yet yielded practical results. The main reason for the lack of oil on the mainland is the paucity of basins with sufficient thickness of marine sedimentary rocks in which oil could accumulate.

1.2 Climatic conditions of the mainland Australia is the driest continent on earth; three quarters of its surface has insufficient moisture. The climatic conditions of Australia depend, first of all, on the characteristics of its geographical location on both sides of the southern tropic. In addition to geographic latitude, the climate of the continent is influenced by the peculiarities of atmospheric circulation, relief, and weak ruggedness. coastline and ocean currents, as well as the large extent of the continent from west to east. Most of Australia is dominated by trade winds. But their influence on the climate of the eastern mountainous and western lowland parts of the continent manifests itself in different ways. In the extreme south, climate formation is influenced by the influence of westerly winds during the cold season temperate latitudes. The north of the continent is influenced by the northwestern equatorial monsoons. The shallow ruggedness of the coastline and the mountain barrier in the east of the continent significantly weaken the influence of the surrounding oceanic waters on the climate of the inland (tropical) parts of Australia. Therefore, the climate of the most extended part of the continent from west to east is surprisingly dry and continental. The continent is entirely located in the southern hemisphere, and the change of seasons here is inverse to the seasons of the northern hemisphere: the hot season occurs in November - January, relatively cold - in June - August. Due to its position primarily in tropical latitudes, the continent receives a huge amount of solar heat. Average summer temperatures here range from 20 to 280 C, winter temperatures from 12 to 240 C. The lowest winter temperatures on the plains do not fall below -40, -60 C, only in the Australian Alps there are frosts down to -220 C. The change of seasons is quite clearly manifested only in the northern and southern parts of the continent, but it is expressed not so much in seasonal changes in temperatures, which are quite high everywhere, but in the seasonality of precipitation. " Wet season" and "dry season" in Australia are concepts that are associated with very sharp changes in plant aspects, living conditions, and economic opportunities. The moisture content of the territory varies within very wide limits. The northern, eastern and southern outskirts of the continent receive more than 1000 mm of precipitation per year (only 1/10 of its area), but in the interior regions, which occupy almost half of the continent, the annual precipitation does not reach 250 mm. In the northern half of Australia, precipitation falls mainly in summer, in the southern half - in autumn and winter, and only on the east coast - all year round. However, there are virtually no areas in Australia that experience a dry season. Even in the east and southeast, the relatively dry season lasts 3-5 months. In inland Australia there are severe droughts every 10-15 years, however, in some months the amount of precipitation can be 10-15 times higher than the average monthly norm. Catastrophically heavy rains wash away highways and railways, wash away crops, and cause enormous damage to the economy. Australia is located in four climatic zones - subequatorial, tropical, subtropical and temperate (Tasmania Island). In the subequatorial climate zone is the territory north of 20 0 S. w. There are constantly high temperatures (about 250 C) and large contrasts in humidity associated with the dominance of summer time(December – February) humid equatorial air masses, in winter (June - August) - dry tropical. Only along the eastern coast of the Cape York Peninsula are air humidity and precipitation high in all months, although their summer maximum is noticeable here too. Tropical cyclones hit the northwestern and northeastern coasts once or twice a year. Tropical cyclone season is considered to be from November to April, but in general they can occur in any month. On average, there are up to 14 cyclones per season, 5 of which are hurricane force. Winds, the speed of which can exceed 30 m/sec, often cause devastation on the coast. The vast area west of the Great Dividing Range, lying between the 20th and 30th parallels, has a tropical, hot and dry climate with a very wide range of temperatures, with occasional precipitation. For 3-4 summer months in a row, the mercury column during the day can remain above 370C, often reaching 48-510C. In winter, 10-150C. Precipitation amounts to 250-300 mm. On the west coast, due to the cold current, the air temperature is lower. In the same latitudes, but east of the Great Dividing Range, the coastal plains and mountain slopes are characterized by hot, but very rainy summers and warm, less humid winters. Here, the eastern slopes of the Great Dividing Range are influenced by moist air masses coming from the Pacific Ocean. Air saturation with moisture increases under the influence of the warm East Australian ocean current. Precipitation is 1000-1500 mm. The greatest diversity is in the subtropical climate zone, which extends south of the thirtieth parallel. There are three types of climate in the belt: subtropical humid - in the southeast, subtropical continental - along the Great Australian Bight, subtropical Mediterranean - in the southwest of the continent. So, in the region of a subtropical humid climate, precipitation falls throughout the year with a summer maximum, January temperatures are about 220C; July about 60C. continental type The climate is characterized by low precipitation throughout the year and rather sharp annual and daily temperature fluctuations. The peculiarity of the Mediterranean climate is autumn and winter rains, hot dry summers, average precipitation 500-600 mm. Tasmania has the mildest and wettest climate. Most of the island is located in temperate zone with warm, windy winters and relatively cool summers. In the west of the island, facing the humid winds, precipitation is abundant in all seasons; in the east, lying in the wind shadow, there is a rainless period in the summer.

Australia, having separated from Gondwana in the Jurassic period, has been subject to slow uplifts, subsidences, and faulting throughout its geological history. Now the mainland is a plateau with an average height of 350 m, i.e. It is the lowest part of the land after Europe. Its climatic conditions are dry and continental.

2. Inland waters Australia 2.1 Mainland river system Australia's river system is small. The deepest, although short, rivers flow into the Pacific Ocean from the well-moistened eastern slopes of the Great Dividing Range. On the contrary, almost all rivers belonging to the Indian Ocean basin dry up for a long time. Much of the Western Australian Tablelands and Central Lowlands is crossed only by a sparse network of dry channels (creeks) that fill with water after occasional rainfall. In especially high-water years, the longest and most branched creeks flow into Lake Eyre, but in most cases their mouths are lost in the sand.

The flow characteristics of Australia and the islands close to it are well illustrated by the following figures: the flow volume of the rivers of Australia, Tasmania, New Guinea and New Zealand is 1600 km3, the runoff layer is 184 mm, i.e. slightly more than in Africa. And the volume of runoff in Australia alone is only 440 km3, and the thickness of the runoff layer is only 57 mm, i.e., several times less than on all other continents. This is due to the fact that most of the mainland, unlike the islands, receives little precipitation and there are no high mountains or glaciers within its borders.

The inland drainage area covers 60% of Australia's surface. Approximately 10% of the territory drains into the Pacific Ocean, the rest belongs to the Indian Ocean basin. The main watershed of the continent is the Great Watershed Range, from the slopes of which the largest and deepest rivers flow. These rivers are fed almost exclusively by rain.

Since the eastern slope of the ridge is short and steep, short, fast, winding rivers flow towards the Coral and Tasman Seas. Receiving more or less uniform feeding, they are the deepest rivers in Australia with a clearly defined summer maximum. Crossing ridges, some rivers form rapids and waterfalls. The length of the largest rivers (Fitzroy, Burdekin, Hunter) is several hundred kilometers. In their lower reaches, some of them are navigable for 100 km or more and are accessible to ocean-going ships at their mouths.

The rivers of Northern Australia flowing into the Arafura and Timor Seas are also deep. The most significant are those that flow from the northern part of the Great Dividing Range. But the rivers of northern Australia, due to the sharp difference in the number of summer and winter precipitation have a less uniform regime than the rivers of the east. They overflow with water and often overflow their banks during the summer. monsoon rains. IN winter time- These are weak, narrow watercourses that dry up in places in the upper reaches. The largest rivers of the north - the Flinders, Victoria and Ord - are navigable in the lower reaches for several tens of kilometers in summer.

There are also permanent watercourses in the southwest of the mainland. However, during the dry summer season, almost all of them turn into chains of shallow, polluted ponds.

There are no permanent watercourses in the desert and semi-desert interior parts of Australia. But there is a network of dry channels there, which are the remnants of a formerly developed water network, formed under the conditions of the pluvial era. These dry riverbeds fill with water after rains for a very short time. Such periodic watercourses are known in Australia as "creeks". They are especially numerous on the Central Plain and are directed towards the drainless, drying Lake Eyre. The Nullarbor Karst Plain is devoid of even periodic watercourses, but has an underground water network with flow towards the Great Australian Bight.

The most developed river network is on the island of Tasmania. The rivers there are fed with mixed rain and snow and are full of water throughout the year. They flow down from the mountains and are therefore stormy, rapids and have large reserves of hydroelectric power. The latter is widely used for the construction of hydroelectric power stations. The availability of cheap electricity contributes to the development of energy-intensive industries in Tasmania, such as the smelting of pure electrolyte metals, the production of cellulose, etc. The lack of surface water is partially compensated by large reserves of groundwater that accumulate in artesian basins. Australia's artesian waters contain a lot of salts.

The rivers flowing from the eastern slopes of the Great Dividing Range are short and flow in narrow gorges in the upper reaches. Here they may well be used, and in part they are already used for the construction of hydroelectric power stations. When entering the coastal plain, rivers slow down their flow and their depth increases. Many of them in estuarine areas are even accessible to large ocean-going vessels. The Clarence River is navigable for 100 km from the mouth, and the Hawkesbury for 300 km. The flow volume and regime of these rivers are different and depend on the amount of precipitation and the time of its occurrence. (Appendix B)

The Fitzroy River is located in the East Australian Mountains. It flows into King Bay of the Indian Ocean. Like other rivers in Australia, the Fitzroy is fed by rainwater; to a lesser extent, its water level depends on melting snow and groundwater. Despite its shallow depths, Fitzroy is navigable (approximately 130 kilometers upstream from the mouth). Fitzroy has no major tributaries. Fitzroy doesn't freeze.

The source of the Murchison is in the Robinson Range. Flows into the Indian Ocean. The river flows through Western Australia. Twice a year (summer and winter) the Murchison riverbed dries up, forming a long string of small lakes. Murchison's way of eating - rain power. A tributary of the Murchison is a small river called the Murchison. Murchison doesn't freeze either.

On the western slopes of the Great Dividing Range, rivers originate and make their way through the interior plains. The longest river in Australia, the Murray (2375 km), begins in the area of ​​Mount Kosciuszko. Its largest tributaries - the Murrumbidgee (1485 km), Darling (1472 km), Goulburn and some others - also originate in the mountains. (Appendix B)

The rivers of the northern and western coasts of Australia are shallow and relatively small. The longest of them, the Flinders, flows into the Gulf of Carpentaria. These rivers are fed by rain, and their water content varies greatly at different times of the year. Rivers whose flow is directed to the interior of the continent, such as Coopers Creek (Barku), Diamantina, etc., lack not only a constant flow, but also a permanent, clearly defined channel. In Australia, such temporary rivers are called " screams"(English) creek). They are filled with water only during short showers. Soon after the rain, the river bed again turns into a dry sandy hollow, often without even a definite outline.

The outlying areas of Australia have flow to the Indian Ocean (33% of the flow from the total area of ​​the continent) and to the Pacific. Rivers that flow into the ocean tend to be short and steep, especially those draining from the East Australian Mountains. The volume of flow, as well as the regime of river levels, is different and significantly depends on the amount of precipitation and the time of its occurrence. The deepest and most uniform in flow are the rivers starting in the East Australian Mountains (Burdekin, Fitzroy, Burnett, etc.). The rivers of the western coast (Fortescue, Gascoyne, etc.) flowing from the semi-desert coastal plateaus are the least deep and unstable. Surface drainage is completely absent on the Nullarbor karst plain adjacent to the Great Australian Bight.

Australia has only two major rivers, the Murray and the Darling. Beginning in the Australian Alps, the Murray is the most abundant river in Australia (basin area 1072 thousand km2, length 1632 m). It is fed mainly by rain and to a lesser extent by snow. Flowing with a barely noticeable gradient across the vast southeastern plains of the Central Lowlands, the river loses a lot of water to evaporation and barely reaches the ocean. At its mouth it is blocked by sand spits. The main tributary of the Murray, the Darling River, is the longest river in Australia (basin area 590 thousand km2, length 2450 m), but it is even less deep, and during dry seasons its waters, lost in the sands, do not reach the Murray.

The large left tributaries of the Murray - the Murrumbidgee and the Goulburn - also maintain a constant flow, during the rainy season, spilling over tens of kilometers. Floods come very quickly, but do not last long, accompanied by severe floods. The rivers of the Murray Basin serve as important sources of irrigation water.

All rivers included in the Murray-Darling system are fed mainly by rainfall and to some extent by snow falling in the Australian Alps. Therefore, maximum consumption occurs in the summer. Before the construction of dams and reservoirs, the floods of the rivers of the Murray system on the flat, low-lying plain sometimes became catastrophic floods. At the same time, the rivers carried large masses of debris and deposited levees along the channels, which often prevented tributaries from flowing into the main river. Currently, the flow of the Murray and all its tributaries is regulated, which has both positive and negative sides. A large number of reservoirs makes it possible to accumulate significant reserves of irrigation water in case of prolonged droughts and at the same time prevents the fairly regular flow of fertile silt into floodplain complexes.

During the dry winter period, the level of the main river drops significantly, but, as a rule, a continuous flow remains throughout its entire length. Only during the years of the most severe droughts do certain sections of the upper reaches of the Murray dry out completely.

The main features of the natural landscapes of the Murray-Darling plains are determined by their position in the tropical and subtropical zones, the increasing dryness of the climate from east to west, as well as the nature of the relief. The northern part of the plains is occupied by a flat basin into which the waters of the Darling and its tributaries collect. The basin is bounded on the south by the low Kobar upland by the uplift of the Paleozoic folded basement, and on the east by the foothills of the East Australian Mountains. The elevated margins of the basin receive up to 400 mm of precipitation per year and are occupied by typical eucalyptus savannas and bushes of acacia bushes. The grass cover, which withers in the dry winter, blooms luxuriantly at the beginning of summer, when rare but heavy rains fall. In the center of the basin, in drier conditions, scrub mulga thickets are common. The basin is drained by the Darling River, which begins in the New England Mountains and very quickly turns from a mountain river into a flat one, with an insignificant fall, thanks to which many branches and channels are separated from the main channel, ending in lake depressions at the bottom of a wide valley. The lakes do not have permanent outlines; after floods, they support the main river for several months, then dry up and during severe droughts the river flow almost stops. Chains of lakes, saline in the lower reaches, remain in the riverbed. In completely rainless years, there is water in the riverbed only for two to three months. The low water content of the Darling in its lower reaches is explained by the fact that in the middle and lower reaches this river is a transit river. Crossing the interior arid regions, it does not receive a single influx for 1,500 km. Navigation on the river is possible only during high water (during four summer months) for 1000 km for shallow draft vessels. The Darling Plains merge in the southwest with the Murray Plains, which lie on the site of a sea bay that existed until the end of the Neogene. The bay was filled not only with marine, but also with alluvial-lacustrine sediments brought by the Murray and its tributaries. The northern part of the plains (to the mouth of the Darling) receives little rainfall, is crossed by wide valleys of temporary streams and is covered with mulga scrub. The main geomorphological element of the southern part of the plains is the Murray Valley. Above the mouth of the Darling it is wide, the river bed meanders in a wide floodplain, in which there are many oxbow lakes and lakes. Below the confluence of the Darling, its banks are quite steep, which indicates vigorous deep erosion of the river: the Murray flows here through an area that only emerged from sea level in the Quaternary and is now still in the stage of uplift. The straightness of the valley below Morgan suggests that the river here is exploiting a meridional tectonic basin parallel to the horst massif of the Lofty Range.

The Murray ends at the vast, shallow Alexandrina Lagoon. It is completely cut off by sand spits, and only artificial channels allow small ships to penetrate it. The Murray's flow fluctuates sharply over the seasons, but unlike the Darling, it does not stop throughout the year. Currently, the flow is regulated by a system of dams and reservoirs. The largest reservoir, Hume, is located near Albury. Up the Murray, ships rise 1,700 km to the city of Albury, but in practice navigation is of little importance due to the lack of free communication with the ocean and the shallow waters of the river. Much of the Murray Lowlands is characterized by aridity. The amount of precipitation (mainly winter) increases slightly (from 250 to 500 mm) from northwest to southeast, and landscapes change in the same direction. Mulga-scrub thickets occupy the driest areas; in wetter ones they are replaced by thickets of mallee scrub, characteristic of the landscapes of the Australian steppes. In the southwest, in the foothills, the increasing role of summer monsoon moisture contributes to the emergence of savannah landscapes with dense grass cover and eucalyptus trees along river valleys and in relief depressions. A special area against this background is the Riverina between the Murray and Murrumbidgee rivers, composed of sandy-clayey alluvial deposits and having a particularly flat topography. In many places the sands have been raised into dunes, now secured by vegetation. The lack of slopes makes it difficult for flood waters to flow out, so the Riverina is rich in small-sized shallow oxbow lakes Murray and Murrumbidgee. South of the Murray lie the arid sandy plains of the Mallee-Wimmera, shielded from the ocean by the Victorian Mountains. The sands are hilly into dunes, elongated latitudinally, in the direction of the prevailing winds and secured by mallee scrub. From the mountains towards the Murray the plains are crossed by the beds of intermittent rivers ending in salt lakes near the Murray. Only on the southern edge of the plains, which is wetter than the northern, do more or less permanent watercourses remain and the dull grayish-green mallee scrub gives way to bright green savannas. A very special landscape region, known as Goyderland, is formed by the Flinders Lofty horst-block ranges and the plains adjacent to them to the east and north. This is an area fragmented by meridional faults, including the faulted Eyre Peninsula, Spencer Gulf, low horst massif of the Yorke Peninsula, Gulf of St. Vincent, the Flinders Range and its southern extension, the Lofty Range. The ridges have rounded or flat tops, but their slopes are strongly dissected by erosion, which is active in the winter wet season.

The rivers of the Murray-Darling system are of great economic importance, since their waters are used to irrigate the fertile but arid lands of the lowlands, an amount of water that in the driest years the Murray does not deliver its own. So much water reaching the ocean is spent for these purposes. In addition, the intensive development of agricultural production (in particular, the use of mineral fertilizers, herbicides, pesticides and other pesticides) within the river basin contributed to severe river pollution - in the middle reaches of the Murray, up to 130 tons of salts are transferred per year. Therefore, if citrus orchards are irrigated with river water, they may die.

Sharp seasonal fluctuations in level and strong accumulating activity of rivers make navigation difficult. For example, the mouth of the Murray is so cluttered with debris that it is completely inaccessible to seagoing vessels. The river itself is navigable to the city of Albury; the lower Darling is accessible to small ships.

The Murray is a large navigable river. Passenger ships can ascend it almost two thousand kilometers to the city of Albury at the very foot of the Australian Alps. Thanks to snow feeding and the Hume Reservoir built in the upper reaches of the river, the water level in the Murray is quite sufficient for navigation throughout the year. Darling is a completely different matter. Although this tributary is two hundred kilometers longer than the main river, its full flow depends entirely on rains. Therefore, during the dry period of the year, in the lower reaches it turns into a chain of separate reservoirs a kilometer and a half long and a hundred meters wide. The Darling becomes a full-fledged tributary of the Murray only during the rainy season, when there is high water. At this time, in some places it spreads over tens of kilometers.

The nature of Australia is unique; animals, birds and fish live here that cannot be found on other continents. Rare species of fish live in the rivers of Australia: butterfly fish, rabbit fish, cat fish, rat fish, frog fish, cattail, roach, bream, carp, salmon, eel and many other species. 2.2 Features of Australian lakes

There are many lake basins in Australia, but all of them are currently deprived of water and have turned into salt marshes. They are located mainly in basins that are filled with water only after rains. Moreover, for a significant part of the year these lakes are covered with a clay-salt crust. Most lakes in Australia, like rivers, are fed by rainwater. They have neither a constant level nor a drain. In summer, the lakes dry up and become shallow saline depressions. The layer of salt at the bottom sometimes reaches 1.5 m. Most of the lakes in Australia are waterless basins covered with salt-bearing clays. On the rare occasions when they are filled with water, they are muddy, salty and shallow bodies of water. There are many such lakes on the Western Tablelands of Western Australia, but the largest are in South Australia: Lakes Eyre, Torrens, Gairdner and Frome. All of them are surrounded by wide strips of salt marshes. Along the southeastern coast of Australia there are numerous lagoons with brackish or salt water, separated from the sea by sandbanks and ridges. The largest freshwater lakes are in Tasmania, where some, including Great Lake, are used for hydroelectric power.

The continent's largest lakes are Eyre (9,500 km²), Mackay (3,494 km²), Amadius (1,032 km²), Garnpang (542 km²) and Gordon (270 km²; it is also Australia's largest artificial reservoir). The largest salt lakes are Eyre (9500 km²), Torrens (5745 km²) and Gairdner (4351 km²). (Appendix A)The largest of these is Lake Eyre, which is the remnant of a vast body of water. Water now appears in it only after summer rains. In 1840, Edward Eyre discovered a salt lake in South Australia, which was later named after him. Lake Eyre, on rare occasions when its basin fills completely, is Australia's largest lake and its lowest point - about 15 m below sea level. It is the central point of the vast Lake Eyre basin.

The lake is located in the desert of central Australia, in the northern part of the state of South Australia. The Lake Eyre basin is a closed system surrounding a lake bed, the lower part of which is filled with saline, dense soil due to the seasonal evaporation of trapped waters. The basin of the lake is the drainage center for a vast area and receives a whole system of temporary watercourses - creeks (Coopers, Diamantina, Eyre, etc.). The lake is shallow, highly saline, its area and outline are variable and change depending on the amount of precipitation. Typically the lake consists of two bodies of water - Lake Eyre North and Lake Eyre South. But during the rainy season, the cries bring a large amount of water from the mountains, the lakes become a single full-flowing body of water. In the wettest years, the area of ​​Lake Eyre reaches 15 thousand km2. During the dry period, which lasts a significant part of the year, the flow of water stops, the water in the lake evaporates, and it breaks up into shallow reservoirs, interspersed with areas covered with salt crusts. Even during the dry season, some water remains in Eire, which usually collects in small lakes formed on the salty, dry lake bed. During the wet season, rivers from north-east Queensland flow towards the lake. The amount of water brought by the monsoons determines whether the water reaches the lake; and if so, how deep the lake will be. The lake also experiences minor to moderate flooding due to rainfall in the surrounding areas. There is a yacht club on the lake.

From the northeast and east, the usually dry channels of Diamantina and Cooper Creek approach, quite deeply incised in the lower parts of the valleys due to the recent subsidence of the lake basin. Rare eucalyptus trees grow along the creeks. South of the lake Eyre are the residual salt lakes of Torrens, Gairdner and other smaller ones. They occupy an elongated zone of tectonic subsidence, framed on the east by the Flinders and Lofty ranges, and on the west by the Western Plateau scarp. These lakes are also covered with a crust of salt for most of the year.

Australia's lakes, which are quite significant in number and size, are swamps for most of the year. To the north of Spencer Gulf (but not connecting to it) lies Lake Torrens, surrounded by sand dunes, which has a circumference of 225 km. And to the east of it is Lake Gregory, which may be divided into several separate lakes. To the west of Lake Torrens lies a plateau. Rising to a height of 115 metres, the great Lake Gairdner, which, like countless smaller lakes in the same locality, is extremely abundant in salt and appears to have only recently become separated from the sea water. In general there are obvious signs the fact that the southern coast of the continent still continues to slowly rise from the sea waters.

Lake Hillier on one of the islands of the Recherche archipelago. The water in the pond is bright pink. Its color will remain the same even if you pour lake water into a glass and look at the light. Hillier's mystery is explained simply: the lake was once formed on the site of a lagoon - it is separated from the Indian Ocean by a thin strip of land. The sea water in the lake evaporates under the rays of the sun and becomes increasingly salty. Apart from bacteria and microscopic algae, no one lives in the lake. And the strange color is nothing more than a product of the vital activity of its inhabitants.

Amadius is a drying, endorheic salt lake in central Australia. Located approximately 350 km to south-west from Alice Spring. Area – about 880 km2. Due to the arid climate, Amadius is a completely dry lake for most of the year. The lake was first explored in 1872 by Ernest Giles, who named it in honor of the Duke of Savoy, King Amadeus 1 of Spain. Although the traveler initially intended to name it in honor of his benefactor, Baron Ferdinand Muller. Amadius is about 180 km long and 10 km wide, making it the largest lake in Northern Territory. Despite the high salt content, it is not mined due to its remoteness from established markets.

Billabong is an Australian word for a small standing body of water, especially an oxbow lake, connected to a flowing body of water. A billabong usually forms when the course of a river or creek changes. The name probably comes from the Wiratüri word bilaban, although some believe the word comes from Gaelic. The billabong is mentioned quite often in works of Australian literature, for example in the poem "Waltzing Matilda" by Australian poet Banjo Paterson, which has become the unofficial anthem of Australia.

Disappointment is a salt lake in Western Australia (Australia). It dries out during the dry months. The lake received its modern name in 1897 and was named so by traveler Frank Hann. Frank Hann), who made significant contributions to the study of the Pilbara region. Noticing a large number of streams in the study area, he hoped to find a large freshwater lake. But to his disappointment, the lake turned out to be salty (translated from English "disappointment"- disappointment).

Lake Saint Kleyer was formed under the influence of glaciers over the past 2 million years. This deepest lake in Australia is the source of the River Derwent. The surrounding area of ​​the lake offers excellent walking conditions.

Torrens is the second largest saline endorheic rift lake in Australia, in the state of South Australia, located 345 km north of Adelaide. The indicated area of ​​the lake is very arbitrary, since over the past 150 years it has been completely filled with water only once. Discovered by Edward Eyre in 1839, for the next 20 years Lake Torrens was believed to be a huge, shallow, horseshoe-shaped salt lake surrounding the northern Flinders Ranges and blocking the inland route. The first European to overcome this mythical barrier is A. Gregory. The lake is now part of Lake Torrens National Park, which requires special permission to enter.

Frome (English) Lake Frome listen)) is a large endorheic lake in the Australian state of South Australia, located east of the Flinders Ranges. Frome is a large, shallow, dry lake covered with a crust of salt. The lake is about 100 km long and 40 km wide. Most of the lake is below sea level. Area - 2.59 km². Occasionally it fills with brackish water from dry creeks originating in the Flinders Ranges west of Frome, or exclusively with water from Strzelecki Creek to the north. To the west, Lake Frome is adjacent to the Wolkatuna-Gammon Ranges National Park. Vulkathunha-Gammon Ranges National Park), is connected to the north by Salt Creek and Lake Callabonna, to the east by the Strzelecki Wilderness, and to the south by the Frome Downs pastoral estate. The amount of precipitation in the region where the lake is located is minimal, and the nearest locality, the village of Arkarula, is located 40 km to the northwest. In the immediate vicinity of the lake there are two large uranium deposits. The lake was named in 1843 after the British officer and Surveyor General of South Australia, Edward Charles Frome. In 1991, due to its "regional geological significance", Lake Frome was declared a regional nature reserve.

Lake Cynthia or C-Lake is at the southern end of the Cradle C-Mountain Lake in the Tasmanian Wilderness World Heritage region. It is Australia's deepest natural freshwater lake at 200 meters deep. The source of the Derwent River, which eventually heads towards Hobart, Lake St., is also known by its Aboriginal name, which means “sleeping water.” It is at Lake C that the Overland Trail ends in the south. At the southern end of Lake Cynthia Bay, which is connected by a 5 km access road from the Highway.

The salt lake Lake Gairdner, 160 kilometers long and up to 48 kilometers wide, is the fourth largest after lakes Eyre, Torrens and Frome. The layer of salt in some places can exceed 1 meter. The lake is located in the north of South Australia, 450 kilometers from Adelaide. Access to the lake is limited due to private pastures surrounding the lake on all sides. The most popular access points to the lake are Mount Ive Farm to the south and the campsite to the southwest along the road between Moonaree and Yardea. Gördner is part of a system of four large endorheic lakes left over from the ancient inland sea, extending to the north of Australia to the Gulf of Carpentaria. The lakes are located on a rocky plateau, not a single river flows out of them, and they are filled only with rainwater. In the summer, when there is not a drop of water left, races are held on the lake. The absolutely flat surface of the lake and the long route allow you to develop enormous speeds. The current record (as of 2008) is 301 mph. Dried salt forms crystals of all sorts of shapes. The taste is salty and bitter. Near the shore, under a layer of salt, there is wet clay. Most beautiful lake looks at sunset and dawn - the low sun illuminates the salt crystals and emphasizes the bottom topography. In addition, at this time it is not so bright and not hot. During the day, the lake becomes dazzling white and you can do without sunglasses for no more than 2-3 minutes. It also seems that the sun is burning from all sides.

2.3 Australian groundwater

A distinctive feature of Australia is its wealth of groundwater. They accumulate in artesian basins occupying troughs of the ancient foundation along the edges of the Western Plateau and in the Central Lowland. The aquifers are mainly Mesozoic sediments, and the dense Paleozoic rocks are water-resistant. Groundwater is recharged primarily from atmospheric precipitation. Groundwater in the central parts of the basins lies at great depths (up to 20 m, in some places up to 1.5 km). When drilling wells, they often come to the surface under natural pressure. The area of ​​artesian basins here exceeds 3 million km2, which is about 40% of the country's territory. In most basins, the water is brackish, warm, and the aquifers lie at considerable depths (up to 2000 m), which makes their use difficult. The total area of ​​basins with groundwater reserves exceeds 3240 thousand square meters. km. Water supply through underground flow has great importance for many rural areas of Australia. These waters mostly contain dissolved solids that are harmful to plants, but in many cases the water is suitable for watering livestock. Although the groundwater is often very warm and highly mineralized, the area's sheep industry depends on it. However, groundwater is also used quite widely in the mining industry. Smaller artesian basins are found in Western Australia and south-east Victoria. In the semi-desert and desert regions of Australia, artesian basins are of great importance. But due to the mineralization of water, they are used not so much for irrigation as for the needs of industry and transport and, mainly, for creating reservoirs in pastoral areas (in southern Queensland, New South Wales and Victoria).

The Great Artesian Basin, the largest in the world, covers an area of ​​1,751.5 thousand square meters in Queensland, South Australia, New South Wales and the Northern Territory. km. It covers almost the entire Central Lowlands from the Gulf of Carpentaria to the middle reaches of the Darling River, and accounts for more than half the groundwater area. The pool area has greatest number artesian wells that provide mineralized water, sometimes warm and even hot. But due to the mineralization of water, they are used not so much for irrigation as for the needs of industry and transport and, mainly, for creating reservoirs in pastoral areas (in southern Queensland, New South Wales and Victoria).

Almost one-third of the continent's area, mostly inland, is desert or semi-desert, not occupied by agricultural land. 60% of the territory is drainless, only one large Murray-Darling system in the south-east of the country is used for shipping and irrigation.

Conclusion

The position of most of the continent in the zone of desert and semi-desert tropical climate determines the weak development of surface runoff, both external and internal. In terms of total annual runoff, Australia ranks last among other continents. Over almost its entire area, the runoff layer is about 50 mm per year. The runoff layer reaches its greatest values ​​(400 mm or more) on the windward wet slopes of the East Australian Mountains. 60% of the continent's area has no flow to the ocean and has only a sparse network of temporary watercourses (creeks). The densest network of calls is in the Central Basin, with much less on the Western Plateau. Water appears in them only after episodic rainfalls; they often end in drainless basins, which in the pluvial era of the Quaternary period were large freshwater lakes fed by the waters of large permanent rivers. Now these lakes are almost dry, their baths are occupied by salt marshes. Even the largest closed lake in Australia, Lake Eyre, is covered with a crust of salt up to 1 m thick in the dry season, and in the rainy season (summer) it overflows over an area of ​​up to 1500 km2. The beds of Australia's longest creeks, Cooper Creek and Diamantina, end at the shores of the lake.

Of all the atmospheric moisture that falls in Australia, only 10-13% enters water bodies, the rest either evaporates or seeps into the soil and is consumed by plants. This is the main reason for the continent's exceptional poverty of surface water. Over the course of a year, only 350 km3 of water flows into the ocean from the entire area of ​​Australia (less than 1% of the total flow of the Earth's rivers). The distribution of surface water across the continent is very uneven. More than half of the river flow comes from poorly developed areas north of the tropics. At the same time, the most important agricultural region, the Murray-Darling Basin, has only 7% of the continent's river flow. The deepest, although short, rivers flow into the Pacific Ocean from the well-moistened eastern slopes of the Great Dividing Range. On the contrary, almost all rivers belonging to the Indian Ocean basin dry up for a long time. Much of the Western Australian Tablelands and Central Lowlands is crossed only by a sparse network of dry channels (creeks) that fill with water after occasional rainfall. In especially high-water years, the longest and most branched creeks flow into Lake Eyre, but in most cases their mouths are lost in the sand. The deepest river on the continent is the Murray, 2,570 km long. Originating on the western slopes of the Australian Alps, it receives additional nourishment from the spring melting of snow. However, outside the mountainous part, flowing with a barely noticeable slope across vast dry plains, the river loses a lot of water due to evaporation, for irrigation and water supply, becomes very shallow and barely reaches its mouth, blocked by sand spits. The Darling is even less deep - main tributary Murray, considered the longest river on the continent (2740 km). In the middle and lower reaches, the Darling dries out for a long time (up to 18 months in a row). The large left tributaries of the Murray - Murrumbidgee and Goulburn - also maintain a constant flow, during the rainy season, spilling over tens of kilometers. Floods come very quickly, but do not last long, accompanied by severe floods. The rivers of the Murray Basin serve as important sources of irrigation water. There are many lake basins in Australia, but all of them are currently deprived of water and have turned into salt marshes. The largest of them is Lake Eyre, which is the remnant of a vast body of water. Water now appears in it only after summer rains. A distinctive feature of Australia is its wealth of groundwater. The area of ​​artesian basins here exceeds 3 million km2, which is about 40% of the country's territory. More than half of this area falls on the world's largest Great Artesian Basin, which occupies almost the entire Central Lowland. In most basins, the water is brackish, warm, and the aquifers lie at considerable depths (up to 2000 m), which makes their use difficult. However, groundwater is used quite widely in livestock farming and mining. One of the most important issues in Australia there is a lack of fresh water, especially in the southeast of the country. Water quality is deteriorating from year to year. Although Australia's river and groundwater have always been characterized by high salinity, its natural level did not prevent agricultural development of the territory. But over time, deforestation and the replacement of natural vegetation with cultivated vegetation, as well as increased water consumption for irrigation of agricultural land, led to an increase in water salinity levels. The quality of river water also decreases as a result of its contamination with solid particles during land erosion, due to the entry of waste from industrial enterprises and runoff from agricultural land into the rivers. Despite the growing role of underground sources, in the near future, mainly river water will still be used to meet the needs of irrigation and urban services, and by the beginning of 2000. their shortage will necessitate the need for additional water sources. Moreover, the lack of water still serves as an obstacle to the development of the interior of the continent.

List of used literature

1. Illustrated atlas of the world. - M.: ZAO "Reader's Digest Publishing House", 1998. - 128 p.

2. Ed. Pashkanga K.V., Physical geography for preparatory departments of universities, M., 1995.

3. Korinskaya V.A., Dushina I.V., Shchenev V.A., Geography 7th grade, M., 1993.

5. Romanov A.A., Saakyants R.G. Geography of tourism: Textbook. – M.: Soviet Sport, 2002. – 400 p.

7. Anichkin O. Australia. M.: Mysl, 1983.

8. Vlasov T.V., Physical geography of continents, M., “Enlightenment”, 1976.-304 p.

9. Pritula T. Yu., Physical geography of continents and oceans: textbook. higher allowance textbook institutions / T. Yu. Pritula, V. A. Eremina, A. N. Spryalin. – M.: Humanitarian. ed. VLADOS center, 2004. – 685 p.

10. Davidson R. Travel never ends. M.: Mysl, 1991.

11. Lucian Volyanovsky “The continent that has ceased to be a legend”, M., 1991.

12. Skorobatko K.V. Guide to Australia. - Publisher: Avangard, 2003. – 160 s.

13. Anichkin O.N., Kurakova L.I., Frolova L.G., Australia, M., 1983.

14. Ratanova M. P., Baburin V. L., Gladkevich G. I. et al.; Ed. M. P. Ratanova. Regional studies. Manual for universities / – M.: Bustard, 2004. – 576 p.

15. Bogdanovich O.I. Countries of the world: Encyclopedic reference book. – Smolensk: Rusich, 2002. – 624 p.

16. Sheremetyeva T.L., Ragozina T.O. The whole world: Countries and capitals. – Mn.: Harvest LLC, 2004. – 976 p.

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18. Yashina I.G. Australia. – Directory, 2002 – 351 p.

Appendix A

Largest lakes in Australia

Appendix B

Largest rivers

Related information.

• Read: Nature of Australia; Freshwater bodies of the Earth

Rivers and lakes of Australia

Rivers of Australia

Most of the Australian mainland receives little rainfall, so most of Australia's rivers dry up. And only those that begin in the mountains of Eastern Australia, as well as the rivers of Tasmania, have a constant flow all year round.

The Murray River, together with its major tributaries the Darling, Murrumbidgee and Goulburn, is Australia's main river artery. It covers an area in New South Wales, Victoria, Queensland and South Australia with a total area of ​​about 1073 thousand square meters. km. The Murray River originates in the Snowy Mountains and flows into Encounter Bay in South Australia. The total length of the Murray River is 2575 km, with the lower 970 km navigable but only for small vessels. Sandbanks blocking the mouth of the river serve as an obstacle to the entry of sea vessels. The Murrumbidgee tributary, which is 1690 km long, begins in the Cooma area and flows into the Murray. The main Darling River, 2,740 km long, flows into the Murray at Wentworth.

Slightly more than half of the continent has separate drainage or belongs to internal drainage basins. On the Western Plateau, the flow is isolated, and the streams that exist there function rarely and for a short time, and end in temporary lakes or swamps confined to drainless basins. The Lake Eyre basin, one of the world's largest inland drainage basins, covers an area of ​​1143.7 thousand square meters. km and occupies most of the territory of Queensland, Northern Territory and South Australia. Such large rivers of this basin as Georgina, Diamantina and Cooper Creek are also interesting. And since they are characterized by very small slopes of flow, most of the time they are real labyrinths of dry intertwining channels, but after heavy rains they fill up and quickly spread many kilometers wide. Despite this, the waters of these rivers rarely reach Lake Eyre. It was noted that only in 1950 its basin was filled for the first time since the colonization of the mainland by Europeans.

The use of Australian rivers is extremely difficult because their flow is extremely variable. In addition, there are few areas suitable for the construction of dams, especially in inland areas, and large reservoirs are needed to ensure a constant water supply. In addition, in Australian arid regions, water losses due to evaporation are very significant, and only in Tasmania is the flow quite constant in all seasons.

Most of the time, the lakes of Australia are waterless basins that are covered with salt-bearing clays. Therefore, in rare times when they are filled with water, they are silted, salty and shallow reservoirs. The largest of them: lakes Eyre, Torrens, Gairdner and Frome are located in South Australia. And there are many such small lakes in the Western Tablelands of Western Australia. Numerous lagoons with brackish or salt water are located along the southeastern coast of Australia, and they are separated from the sea by sandbanks and ridges.

Tasmania is a territory richer in fresh water, so it is here that the largest freshwater lakes are located, and some of them, in particular the Great Lake, are used for hydroelectric purposes.

Water supply from groundwater is vital to many rural areas of Australia. Experts have calculated that the total area of ​​basins with fresh groundwater reserves exceeds 3,240 thousand square meters. km. However, these waters mostly contain various dissolved solids, which often have a harmful effect on plants when watering, but in many cases this water is suitable for watering livestock.

The world's largest, the so-called Great Artesian Basin, is located in Queensland, South Australia, New South Wales and the Northern Territory, which covers an area of ​​1,751.5 thousand square meters. km. Despite the fact that groundwater is often very warm and highly mineralized, sheep farming in this region depends on it. Artesian basins have also been discovered in Western Australia and south-east Victoria, but of much smaller sizes.

When it comes to hot, dry climates, Africa immediately comes to mind with its endless deserts that stretch for hundreds of kilometers. Meanwhile, Australia is considered the driest continent. Rain is rare here. And although the continent is washed by seas on all sides, its territory receives five times less precipitation than in Africa. The bulk of this precipitation occurs in the southeastern part of the country. The largest rivers and lakes in Australia are concentrated there.

Due to lack of rain, the rivers on the mainland are low. Moreover, many of them periodically dry out completely. But despite the harsh climate, Australia is known for its beautiful landscapes and amazing nature. Life here is so full of abundance.

There are quite a lot of salty bodies of water on the mainland. Also, some large rivers carry salt water. Which is a very rare occurrence and an unusual feature of Australia. This part of the world is characterized by a climate with changing seasons. When a dry period gives way to heavy rains. Therefore, during the rainy season, most rivers quickly fill up and overflow their channels, spilling over the surrounding area. And after a few months they dry out again under the scorching sun.

Characteristic features of Australian rivers

Despite the fact that most of the rivers in this country cannot be called high-water, due to lack of rain. Generally water map Australia has a developed river network, which consists of many rivers and reservoirs.

Almost all rivers originate on the slopes Great Dividing Range. These rivers are seasonal rather than deep. In summer they dry out or become so shallow that even a child can ford such a river. And in winter they fill up again. Some of them are destined to end their journey in the deserts of the central part of the country. And others feed salt lakes or flow into larger rivers.

Murray River

One of these rivers is the Murray. Its length is more than 2500 kilometers. Together with its right tributary, the Murray forms the main Australian river system. After which it flows into the bay in the Pacific Ocean. The river is fed by rain and melting snow on the western slopes of the ridge. The Murray flows all year round, like all Australian rivers it can become shallow depending on the time of year, but it never dries up. It is also one of the few rivers that can boast of being navigable. Of course, it should be noted that you will not find heavy seagoing ships on Murray. From time to time, some of the river's tributaries dry up due to irrigation. And during such periods the Murray is rich in sand shoals. Ships do not sail along the entire river, but only in its lower part. The length of the shipping route is 1000 kilometers, which is a record for Australia.

Darling tributary

This is the longest tributary of the Murray. The total length of these two rivers is about more than 3,500 kilometers. And together they form the country's widest water network. Ranking second in length on the mainland, the Darling flows through a saline semi-desert area. Rainfall is infrequent in this part of Australia. Therefore, for most of the year, like many other rivers, it is low-water, although it does not dry out completely.

Australian screams

This name does not mean the cries of wild animals in the night forest. This is the name given to small watercourses (another unusual phenomenon). They are not classified as full-fledged rivers. Because they appear only with the arrival of rains. This phenomenon is typical for desert areas in the west and central part of the continent. The most famous such channel is Cooper Creek. With the onset of the rainy season, these watercourses fill up and carry their waters through saline soils into larger bodies of water. And in the dry months they cease to exist. Of course, the cries are of great importance to the continent's water network.

All rivers of Australia

The rivers of Australia number only about seventy points. But here we need to remember that this is still the smallest continent on the planet. The length of some rivers is only 10-15 kilometers, such rivers as Lane Cove, Queen, Prospect Creek. But despite this, like screams, they contribute to the nature of Australia.

There are plenty of large rivers in Australia besides the Murray. They are located in different parts of the continent and range from several hundred to several thousand kilometers. The northern part of the country is Adelaide. This river is also navigable. The country's western waterway is the Gascoigne, which stretches for almost 1000 kilometers. And also the Murrumbidgee, one of the few Australian rivers where a dam was built. The river stretches for about 1,500 kilometers, after which it flows into the notorious Murray. Hunter - Overflowing river periodically creates floods in New South Wales.

Features of Australian lakes

Due to the harsh, dry climate, Australia has very few lakes. In addition, almost all of them are salted. The largest lake is called - Air. It is also salty and is located sixteen meters below sea level. This feature is typical for most water bodies in Australia. It should be noted that lakes suffer from a lack of rain no less than rivers. Since the latter are the main source of food for lakes. Lack of rainfall affects everywhere. Reservoirs become shallow and dry. During the dry season, small Australian reservoirs resemble overgrown quarries, and larger ones break up into several reservoirs. Due to the fact that the water level in the lakes is constantly changing, they do not have clear shoreline boundaries. Their outlines change depending on the level of precipitation.

Lakes of Australia

As mentioned above, the largest lake in Australia (covering approximately one sixth of the continent) is Air. It was named after its discoverer. The lake fills during the rainy season, and during this period it can reach a depth of 15 to 20 meters. The Eyre is the largest endorheic basin on the continent. The lake loses water only through evaporation, apart from rare cases when it can overflow its banks.

Torrance- This is the second largest reservoir in the country. It is interesting that over the past century and a half it has been filled only once. It is located in the south of the country in the protected area of ​​the national park. Like Eyre, Lake Torrens has no outflows.

Another southern reservoir - Frome. Unlike previous reservoirs, in addition to rain, it is additionally filled with screams.

freshwater lake Gregory(which is very rare for Australia) is located in the western part of the country. It is perhaps the most “inhabited” body of water on the mainland. It is thanks to the fresh water that there is such a wide variety of flora and fauna here. However, scientists do not give him any comforting predictions. It is believed that under the influence of a dry climate, it will also gradually become salty.

Another amazing lake Hiller. It is located on Middle Island in the western part of the country. The lake is famous for the fact that its water is bright pink. The reason for this is special bacteria that live in the salty water of the lake. The island is currently closed to visitors in order to preserve its ecosystem.

Man-made lakes of Australia

Compared to other parts of the world, the number of man-made lakes in Australia is not large. This is partly due to the topography of the mainland. It has a sort of concave shape in the center and elevations at the edges. In addition, sixty percent of Australia is practically waterless. Much more favorable conditions is located on the island of Tasmania. It has not only a flat mountainous topography, but also a greater amount of precipitation.

Argyll is a huge reservoir in Western Australia. The reservoir is home to more than twenty species of fish, including valuable species. The fish that is caught here is happily sold to restaurants and for sale. In addition, the reservoir supplies water to 150 kilometers of land for agricultural needs. Walking along the shores of this lake is not recommended as there is a high probability of encountering one of the 25,000 crocodiles that live there. Who also fell in love with local fishing.

Some might say that Australia's rivers and lakes are not majestic. And that there are more abundant rivers and deeper lakes in the world. But the Australian mainland itself is not very large. In addition, some natural phenomena are unique here.

Australian groundwater

Residents of Australia are very sensitive to the water reserves on their continent. For about 150 years, various hypotheses have been put forward and research has been carried out on the search and conservation of fresh water. Currently, eleven artesian pools are open. Underground they occupy a huge territory. Their total area makes up a third of the country. And one Great Artesian Basin of Queensland, in area, contains three Frances.

Underground reserves are replenished by rainwater. It seeps into the ground and spreads in different directions. The speed of movement of this water is only a few meters per year. Gradually it reaches underground reservoirs and fills them. Nature loves balance. Therefore, if one of the pools overflows, the water rushes out in a spring and forms temporary watercourses until all the excess water is forced out. These springs are mostly fresh, but sometimes there are also mineral springs.

A special committee has been created to preserve underground swimming pools in Australia. He carefully monitors existing and used wells. The government also willingly sponsors scientific developments in this area.

One of the recent achievements is a unique software, which made it possible to map how Australia's waters have been distributed since ancient times. Taking advantage of these developments, scientists may be able to trace ancient water reserves.

As always in the scientific world, there are scientific geologists who refute these data. Whether there are still water resources hiding under Australian lands remains a mystery. And who of the scientists is right and who is wrong is unknown. This will become clear only with the passage of time.

From all of the above, the conclusion suggests itself that Australia needs additional sources of drinking water. Large cities and agriculture use hundreds of thousands of cubic meters of water every year. Of course, seasonal rains on an arid continent cannot replenish these resources. Therefore, the mainland is slowly using up its underground reserves.

Moreover, these reserves are also by no means ideal. Since this water cannot be used immediately, due to the fact that it contains sulfur and its compounds in large quantities.

Water reserves in artesian springs are full. And they are not yet close to exhaustion. But Australian residents are already thinking about the comfortable existence of their future generations.

The Murray is considered a major river not only by the standards of its continent. The total length of the Murray is 2375 km, and together with the Darling it is almost two hundred kilometers longer than the Volga. But in terms of the abundance of water, the Murray is significantly inferior to most large European rivers.

Australia's longest river is quite easy to find in the eastern part of the continent. Her path passes through a variety of natural landscapes: mountains, forests, swamps. The river flows past cities and agricultural land. Murray and its people attract a variety of life forms that have successfully adapted to its characteristics.

The Murray originates in the highest mountains of the southern continent, the Australian Alps. The largest tributaries of the river begin much to the north. Flowing from east to west, the Murray receives less and less precipitation, but still remains a deep river. If you go downstream, you can get acquainted with all the diversity of the flora and fauna of Australia.

In the vast expanses of the lower Murray you can find Australia's largest birds, the emu and the kangaroo.

Features of the Murray River

The Murray River has the distinction of being free for navigation throughout the year. The width of the river in some places reaches a kilometer. Passenger ships rise almost two thousand kilometers along its current. But the navigation characteristics of its tributary, the Darling, depend almost entirely on the amount of precipitation.

A very large proportion of the Murray's waters are used to irrigate the land. A carefully designed irrigation system serves this purpose. To properly distribute the water resources of the Murray, dams have been built along the entire length of the river. The Murray Basin also has an artificial lake that collects rainwater.

It is the water resources of Australia’s longest and deepest river that make it possible to transform desert areas into lush plains.

There is a project that assumes that the waters of all the small rivers that flow down the eastern slopes of the mountain system will be released into the Murray. If the project can be implemented, the river beds could be turned in a westerly direction, after which they would bring their waters to Murray. Thanks to this, the capabilities of the irrigation system of the river complex will greatly increase.

Australia is a dry continent. A significant part of the precipitation that falls here evaporates. The rest is carried away by the rivers. Moreover, half of the total amount of sediment carried away by rivers falls on the largest river in Australia. For this reason, the importance of Murray in the life of the country can hardly be overestimated.

Many people who are far from geography believe that the driest and most waterless continent on Earth is Africa with its famous deserts. However, this is a deep misconception. Distant and mysterious Australia, of course, is much smaller than Africa and appears less often in international news, but in terms of aridity it ranks first. The volume of precipitation falling on its territory is 5 times less than that of Africa.

At the same time, rivers and lakes must be fed by something, from somewhere they must receive new water to replace that which has evaporated from their surface. The main source of replenishment for most rivers in the world is rain and melting snow, and it is the problem with precipitation in Australia. So this continent does not have truly large rivers, especially those that could be called high-water.

Location of Australian rivers

However, if this island-continent were completely waterless, it would hardly be able to boast of any living creatures and vegetation, and people would not have developed it. So there are bodies of water here.

Another thing is that Australia's rivers are mostly concentrated in the southeast of the country. Most of the rain that falls on the mainland falls here. That is why all the major rivers of Australia flow here, among which the main one is the Murray, and with the accompanying tributary, the Darling. This system begins with the peaks of the mountains, called the Great Dividing Range, and despite the arid climate, it never completely dries out. This is explained by the fact that Murray is fed not only by rainwater, but also by snow, which has chosen the tops of the specified ridge and regularly melts in due time. It is this watercourse that can be called full-flowing and navigable, because it (and this is unlike other rivers in Australia) is accessible even to fairly heavy vessels all year round. Let us remind you: this is by no means typical for the described part of the land.

It should be clarified that the navigability of the Murray, despite the fact that it belongs to the category of “large rivers of Australia,” concerns only the lower thousand kilometers (despite the total length of the river being more than two and a half thousand). And for deep-seated sea vessels, Murray is generally inaccessible: it is replete with sandy shoals, and they block the very mouth. So ships with low draft cannot enter it.

Features of Australian rivers

As anyone who remembers anything from geography lessons knows, all the rivers in the world must flow somewhere. Usually this is the sea or ocean. But the rivers of Australia have distinguished themselves here too. Most of the existing reservoirs do not drain into the ocean. Moreover, they can generally be called a non-constant quantity. The vast majority of waterways on this continent are dry rivers of Australia. That is, they fill with water during short but heavy rains, overflow, flooding the surrounding area, and again become dry riverbeds.

No less interesting is that some of Australia's large rivers and lakes (especially the latter) contain salt water. Actually, we can say that on this continent the problem is not with water, but with its fresh variety.

Darling River

This waterway is something between the Murray and other rivers. It does not have additional “food” in the form of melting snow caps - its source is located much to the north of its “big brother”. Like the rest of the rivers of Australia, the Darling is on a dry ration and mainly renews its waters from precipitation. However, this is a fairly large waterway, which also has underground power sources. So in the dry months this river becomes much shallower, but does not dry out completely.

Australian screams

This word does not mean loud sounds made by any living creature. This is the name for small and, one might say, temporary rivulets (watercourses) that exist during the rainy season and are completely dry during the hot months. They are characteristic of desert areas inland, the most famous of which is Cooper Creek. It is impossible to say that the Creeks are equal rivers of Australia, but they play their role in its existence.

Lake system

There are very few lakes in Australia. Moreover, as already mentioned, they are salty. The largest Australian lake, named Eyre, is also by no means fresh. All such bodies of water are former inland seas in Australia. All of them are located below ocean level, so it is not at all surprising that they do not offer fresh water. The rivers and lakes of Australia are closely connected. It is river flowing water that feeds the lakes, and since there is not enough of it, these reservoirs also dry up. That is why the lake shoreline does not have a clear outline. In the dry season, Australian lakes are more like our clay pits. And even the largest lake in Australia (Eyre) breaks up into a large number of small ponds in the hot months.

Australian lakes overview

Air, as was said, is the largest of them. During the rainy season it is filled with water; at its deepest point its bottom drops 15 meters. This lake is closed. Water is removed from it only by evaporation. This does not apply to rare but heavy rainfalls, during which the Eyre can even overflow its banks and flood the surrounding area. It should be noted that the large rivers and lakes of Australia are tightly interconnected, and without the former the latter long years(or even decades) stand empty.

The next largest lake by volume is Torrance. It also has no drainage and is located in the south of Australia. It is unique in that over the past century and a half it has only been filled with water once. It is a national park, so you can “visit” it only with a special permit.

Also to the south, Lake Frome is equally salty and also drainless. However, one of the creeks (with the unpronounceable name Strzelecki) is located nearby, so this body of water has water much more often than the previous one.

In the north-east of Western Australia there is almost the only Gregory. Scientists, however, suspect that drought will affect it over time, like other rivers and lakes in Australia, meaning it will become salty and rarely fill with water. So far, Gregory is the most populated lake in Australia, rich in flora and fauna (due to its freshwater).

man-made lake

Western Australia also boasts an artificial reservoir called Argyll. Thanks to it, 150 kilometers of agriculture live and feed Australians. Fishing is also good here: unlike other Australian lakes, there is a lot of fish, including valuable species, including sleepy cod (it is loved by fishermen and connoisseurs of fish dishes more than others), barramundi and bony bream. In general, there are as many as 26 species of fish here, which can be considered a unique achievement for this continent. True, fishing (and just walking) along the banks of Argyll should be done very carefully: 25 thousand crocodiles are a good reason for vigilance.

Of course, many fans of scale may not be impressed: the large rivers and lakes of Australia are probably not as majestic as they would like. But do not forget that Australia itself is small (when compared with the continents).

List of Australian rivers

To be honest, the list of everything that can be classified as “rivers of Australia” on the map has 70 items. However, it is hardly worth paying attention to Prospect Creek, which flows for only 17 kilometers, or Lane Cove, which does not reach this distance (its length in the rainy season is only 15 km). There are rivers of even shorter length - the same Queen, which does not stretch up to 13 km. It is clear that for a “drying up” continent, even if it belongs to the category of “drying up rivers of Australia,” it is valuable. But we will not consider it in detail. Let us dwell only on those that can be roughly classified as “large rivers of Australia”.

Which rivers in Australia can be classified as large? Adelaide is in the north of the mainland, stretches as much as 180 km, and is also navigable. The Gascoyne is the longest artery in the west, almost a thousand kilometers (978), and also has a drainage into the Flinders - the winner for the longest in the state of Queensland, flowing for 1004 km. The Lochlan, which covers 1,339 km of Australian territory and flows into the Murrumbidgee. And the Murrumbidgee itself, which reaches almost one and a half thousand kilometers (for the corrosive - 1485), and is also one of the few river sites where it was possible to build a dam.

Very ancient history

From all of the above, it is easy to conclude that Australians are very sensitive to water in general, and fresh water in particular. Research, searches and historical information are something that the inhabitants of the miniature continent take very seriously. And even if at the moment the results of the studies have no practical use, Australians are interested in them... and useful consequences can wait.

Such research includes recent research conducted by the Smithsonian Institution in collaboration with the Australian National University. Scientists created unique software, studied everything they learned from previous researchers, and conducted their own exploration “on the ground.”

The result of the study was a map of the ancient distribution of waters on Australian soil. And since tectonic stability on this continent was established earlier, there is an option to track the “hidden” waters using these studies.

Let's make a reservation: many geologists do not trust the results too much and refute them using other data. But it is not yet possible to completely refute them, so Australia can, using unverified information, try to enrich itself with additional water resources.

Alternative sources of drinking water

From all of the above, it is obvious that Australia is in dire need of fresh water. Neither the rivers (most of which dry up) nor the lakes (which are mostly almost marine) provide it with the required amount of unsalted water. Therefore, the state was forced to turn to alternative sources that could provide what was missing.

Of course, groundwater is not a panacea. Their sulfur content (both pure and in compounds) is too high, but there is often no other source of fresh water.

The good news is that there is a Great Artesian Basin beneath Australia. The bad news is that it will also end someday. And this continent already has to think about what its inhabitants will do next.