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44-562: Toolibin Lake is a seasonal fresh to brackish water perched lake or wooded swamp , in south-western Australia . The lake is contained with a 493-hectare (1,218-acre) nature reserve and it is located about 200 kilometres (124 mi) south-east of Perth , in the Shire of Narrogin , and 40 kilometres (25 mi) east of the town of Narrogin , in the Wheatbelt region of Western Australia . The lake

88-539: A desert climate often face physical water scarcity. Central Asia , West Asia , and North Africa are examples of arid areas. Economic water scarcity results from a lack of investment in infrastructure or technology to draw water from rivers, aquifers , or other water sources. It also results from weak human capacity to meet water demand. Many people in Sub-Saharan Africa are living with economic water scarcity. An important concern for hydrological ecosystems

132-526: A collection of 17 interlinked global goals designed to be a "blueprint to achieve a better and more sustainable future for all". Targets on fresh water conservation are included in SDG 6 (Clean water and sanitation) and SDG 15 (Life on land). For example, Target 6.4 is formulated as "By 2030, substantially increase water-use efficiency across all sectors and ensure sustainable withdrawals and supply of freshwater to address water scarcity and substantially reduce

176-582: A concomitant loss of emergent vegetation. Toolibin is the only major lake in the catchment that has not become completely saline. Toolibin Lake lies in a low rainfall area of the Wheatbelt with an average annual rainfall of 400 mm, mainly falling in May–August, with annual evaporation of 1800 mm. It usually only holds water at certain times of year; sometimes drying out completely for several years; sometimes holding water for extended periods. Toolibin Lake

220-402: A drinking water supply it remains vital to protect due to its ability to carry contaminants and pollutants from the land into lakes and rivers, which constitute a significant percentage of other people's freshwater supply. It is almost ubiquitous underground, residing in the spaces between particles of rock and soil or within crevices and cracks in rock, typically within 100 m (330 ft) of

264-428: A larger salt content. Freshwater habitats can be classified by different factors, including temperature, light penetration, nutrients, and vegetation. There are three basic types of freshwater ecosystems: Lentic (slow moving water, including pools , ponds , and lakes ), lotic (faster moving water, for example streams and rivers ) and wetlands (areas where the soil is saturated or inundated for at least part of

308-558: A population of the threatened red-tailed phascogale . The main threats to Toolibin’s ecological community are salinisation and waterlogging due to clearing of the catchment for dry-land agriculture, particularly wool and cereal grain production; eutrophication caused by run-off containing agricultural fertilizers; invasive weeds changing the structure of the ecosystem and reducing natural vegetation available for food and shelter for animals; and grazing of regenerating seedlings by kangaroos , livestock and rabbits . Actions to recover

352-519: A single factor. Groundwater showed greater resilience to climate change than expected, and areas with an increasing threshold between 0.34 and 0.39 aridity index exhibited significant sensitivity to climate change. Land-use could affect infiltration and runoff processes. The years of most recharge coincided with the most precipitation anomalies, such as during El Niño and La Niña events. Three precipitation-recharge sensitivities were distinguished: in super arid areas with more than 0.67 aridity index, there

396-591: Is considered an active form of sustainable agriculture . The Phoenicians first developed the practice of contour farming and spread it throughout the Mediterranean . However, the Romans preferred cultivation in straight furrows and this practice became standard. This was one of the main procedures promoted by the US Soil Conservation Service (the current Natural Resources Conservation Service ) during

440-449: Is consumed through human activities than is naturally restored, this may result in reduced fresh water availability (or water scarcity ) from surface and underground sources and can cause serious damage to surrounding and associated environments. Water pollution also reduces the availability of fresh water. Where available water resources are scarce, humans have developed technologies like desalination and wastewater recycling to stretch

484-495: Is critical of traditional contour plowing techniques and improves the system through observing normal landforms and topography . At one end of a contour, the slope of the land will always be steeper than at the other. Thus, when plowing parallel runs paralleling any contour, the plow furrows soon deviate from a true contour. Rainwater in these furrows will flow sideways along the falling "contour" line. This can often concentrate water to exacerbate erosion instead of reducing it. Yeomans

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528-416: Is critical to the survival of all living organisms . Many organisms can thrive on salt water, but the great majority of vascular plants and most insects , amphibians , reptiles , mammals and birds need fresh water to survive. Fresh water is the water resource that is of the most and immediate use to humans. Fresh water is not always potable water , that is, water safe to drink by humans . Much of

572-401: Is effective only on slopes with between 2% and 10% gradient and when rainfall does not exceed a certain amount within a certain period. On steeper slopes and areas with greater rainfall, a procedure known as strip cropping is used with contour farming to provide additional protection. Contour farming is most effective when used with other soil conservation methods such as terrace farming , and

616-452: Is extracted for human consumption. Agriculture uses roughly two thirds of all fresh water extracted from the environment. Fresh water is a renewable and variable, but finite natural resource . Fresh water is replenished through the process of the natural water cycle , in which water from seas, lakes, forests, land, rivers and reservoirs evaporates, forms clouds , and returns inland as precipitation. Locally, however, if more fresh water

660-553: Is listed by the Australian Government as a threatened ecological community under the Environment Protection and Biodiversity Conservation Act 1999 . The lake lies in the catchment of the upper Blackwood River at an altitude of 300 metres (984 ft) above mean sea level . It is about 300 hectares (740 acres) in area and 2 kilometres (1.2 mi) in diameter, has a maximum depth of 2 metres (6.6 ft), and

704-520: Is one of the last remaining inland freshwater lakes found in south-western Australia. It is one of a chain of wetlands occupying a palaeodrainage valley forming part of the northern Arthur River system. Most of it is covered with a woodland of water tolerant tree species, with a large open area on the eastern side. Many other Wheatbelt wetlands formerly supported a vegetation community and ecosystem similar to that of Toolibin, but clearing for agriculture has resulted in most such sites becoming saline with

748-479: Is particularly crucial in Africa, where water resources are often scarce and climate change poses significant challenges. Saline water in oceans , seas and saline groundwater make up about 97% of all the water on Earth . Only 2.5–2.75% is fresh water, including 1.75–2% frozen in glaciers , ice and snow, 0.5–0.75% as fresh groundwater. The water table is the level below which all spaces are filled with water, while

792-469: Is recognised as a wetland of international importance under the Ramsar Convention on Wetlands , under which it was designated Ramsar Site 483 on 7 June 1990. The Ramsar site includes the entire area of the lake with some adjacent land on the northern, western and southern sides of the lake added in 2001 since the original site nomination, ensuring a buffer zone of at least 100 m width around most of

836-826: Is securing minimum streamflow , especially preserving and restoring instream water allocations . Fresh water is an important natural resource necessary for the survival of all ecosystems . Water pollution (or aquatic pollution) is the contamination of water bodies , with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes , rivers , oceans , aquifers , reservoirs and groundwater . Water pollution results when contaminants mix with these water bodies. Contaminants can come from one of four main sources. These are sewage discharges, industrial activities, agricultural activities, and urban runoff including stormwater . Water pollution may affect either surface water or groundwater . This form of pollution can lead to many problems. One

880-420: Is the degradation of aquatic ecosystems . Another is spreading water-borne diseases when people use polluted water for drinking or irrigation . Water pollution also reduces the ecosystem services such as drinking water provided by the water resource . Uses of water include agricultural , industrial , household , recreational and environmental activities. The Sustainable Development Goals are

924-531: The Amazon River . The atmosphere contains 0.04% water. In areas with no fresh water on the ground surface, fresh water derived from precipitation may, because of its lower density, overlie saline ground water in lenses or layers. Most of the world's fresh water is frozen in ice sheets . Many areas have very little fresh water, such as deserts . Water is a critical issue for the survival of all living organisms. Some can use salt water but many organisms including

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968-657: The Green Sahara periods) and are not appreciably replenished under current climatic conditions - at least compared to drawdown, these aquifers form essentially non-renewable resources comparable to peat or lignite, which are also continuously formed in the current era but orders of magnitude slower than they are mined. Fresh water can be defined as water with less than 500 parts per million (ppm) of dissolved salts . Other sources give higher upper salinity limits for fresh water, e.g. 1,000 ppm or 3,000 ppm. Fresh water habitats are classified as either lentic systems , which are

1012-632: The University of Nebraska , to promote the method to farmers. By 1938, the introduction of new agricultural techniques, such as contour plowing, had reduced soil loss by 65% despite the continuation of the drought. Demonstrations showed that contour farming, under ideal conditions, will increase yields of row crops by up to 50%, with increases of between 5 and 10% being common. Importantly, the technique also significantly reduces soil erosion and fertilizer loss, making farming less energy and resource-intensive under most circumstances. Reducing fertilizer loss saves

1056-508: The earth 's fresh water (on the surface and groundwater) is to a substantial degree unsuitable for human consumption without treatment . Fresh water can easily become polluted by human activities or due to naturally occurring processes, such as erosion. Fresh water makes up less than 3% of the world's water resources, and just 1% of that is readily available. About 70% of the world's freshwater reserves are frozen in Antarctica . Just 3% of it

1100-629: The 1930s. The US Department of Agriculture established the Soil Conservation Service in 1935 during the Dust Bowl when it became apparent that soil erosion was a huge problem along with desertification . The extent of the problem was such that the 1934 "Yearbook of Agriculture" noted that Approximately 35 million acres [142,000 km ] of formerly cultivated land have essentially been destroyed for crop production. . . . 100 million acres [405,000 km ] now in crops have lost all or most of

1144-494: The area above this level, where spaces in the rock and soil contain both air and water, is known as the unsaturated zone. The water in this unsaturated zone is referred to as soil moisture. Below the water table, the entire region is known as the saturated zone, and the water in this zone is called groundwater. Groundwater plays a crucial role as the primary source of water for various purposes including drinking, washing, farming, and manufacturing, and even when not directly used as

1188-421: The available supply further. However, given the high cost (both capital and running costs) and - especially for desalination - energy requirements, those remain mostly niche applications. A non-sustainable alternative is using so-called " fossil water " from underground aquifers . As some of those aquifers formed hundreds of thousands or even millions of years ago when local climates were wetter (e.g. from one of

1232-425: The environmental values of the lake and its catchment include the reduction of recharge – including revegetation and the protection of remnant vegetation; changes in farming methods, such as contour farming and the use of perennial grasses for grazing; the management of surface water in the catchment to reduce waterlogging of farmland, to decrease the salinity of water entering the lake, and to decrease salt loading of

1276-490: The farmer time and money and decreases the risk of harming regional freshwater systems. Soil erosion caused by heavy rain can encourage the development of rills and gullies which carry excess nutrients into freshwater systems through the process of eutrophication Contour plowing is also promoted in countries with rainfall patterns similar to those in the United States, such as western Canada and Australia . The practice

1320-527: The freshwater flow to be measurably contaminated both by insoluble solids but also by the soluble components of those soils. Significant quantities of iron may be transported in this way including the well-documented transfer of iron-rich rainfall falling in Brazil derived from sand-storms in the Sahara in north Africa . In Africa, it was revealed that groundwater controls are complex and do not correspond directly to

1364-547: The great majority of higher plants and most mammals must have access to fresh water to live. Some terrestrial mammals, especially desert rodents , appear to survive without drinking, but they do generate water through the metabolism of cereal seeds, and they also have mechanisms to conserve water to the maximum degree. Freshwater ecosystems are a subset of Earth's aquatic ecosystems . They include lakes , ponds , rivers , streams , springs , bogs , and wetlands . They can be contrasted with marine ecosystems , which have

Toolibin Lake - Misplaced Pages Continue

1408-469: The lake. Toolibin is the only remaining example in Southwest Australia of a wetland with extensive living thickets of swamp sheoak and the paperbark Melaleuca strobophylla on the lake fringes and bed - one of the main wetland types in the region prior to agricultural development there. Flooded gum , acorn banksia and rock sheoak woodland occur on the higher ground and deep sands surrounding

1452-446: The lake. The vegetation includes submerged aquatic plants and sedges around the lake. The vegetation community provides habitat, now rare in the central wheatbelt, for woodland birds and other animals. Toolibin and its environs support more breeding waterbird species — up to 25, including the rare freckled duck , cormorants, egrets, night herons and spoonbills — than any other inland wetland in south-western Australia. It also supports

1496-823: The lake; and groundwater pumping to lower the water table beneath the lake. Freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids . The term excludes seawater and brackish water , but it does include non-salty mineral-rich waters , such as chalybeate springs. Fresh water may encompass frozen and meltwater in ice sheets , ice caps , glaciers , snowfields and icebergs , natural precipitations such as rainfall , snowfall , hail / sleet and graupel , and surface runoffs that form inland bodies of water such as wetlands , ponds , lakes , rivers , streams , as well as groundwater contained in aquifers , subterranean rivers and lakes . Water

1540-659: The number of people suffering from water scarcity ." Another target, Target 15.1, is: "By 2020, ensure the conservation, restoration and sustainable use of terrestrial and inland freshwater ecosystems and their services, in particular forests, wetlands , mountains and drylands , in line with obligations under international agreements." Subnotes Contour farming Soil erosion prevention practices such as this can drastically decrease negative effects associated with soil erosion, such as reduced crop productivity, worsened water quality, lower effective reservoir water levels, flooding, and habitat destruction . Contour farming

1584-413: The others as well. Water scarcity (closely related to water stress or water crisis) is the lack of fresh water resources to meet the standard water demand. There are two types of water scarcity. One is physical. The other is economic water scarcity . Physical water scarcity is where there is not enough water to meet all demands. This includes water needed for ecosystems to function. Regions with

1628-421: The sea if windy conditions have lifted drops of seawater into the rain-bearing clouds. This can give rise to elevated concentrations of sodium , chloride , magnesium and sulfate as well as many other compounds in smaller concentrations. In desert areas, or areas with impoverished or dusty soils, rain-bearing winds can pick up sand and dust and this can be deposited elsewhere in precipitation and causing

1672-420: The stillwaters including ponds , lakes, swamps and mires ; lotic which are running-water systems; or groundwaters which flow in rocks and aquifers . There is, in addition, a zone which bridges between groundwater and lotic systems, which is the hyporheic zone , which underlies many larger rivers and can contain substantially more water than is seen in the open channel. It may also be in direct contact with

1716-636: The surface, and soil moisture, and less than 0.01% of it as surface water in lakes , swamps and rivers . Freshwater lakes contain about 87% of this fresh surface water, including 29% in the African Great Lakes , 22% in Lake Baikal in Russia, 21% in the North American Great Lakes , and 14% in other lakes. Swamps have most of the balance with only a small amount in rivers, most notably

1760-469: The time). Freshwater ecosystems contain 41% of the world's known fish species. The increase in the world population and the increase in per capita water use puts increasing strains on the finite resources availability of clean fresh water. The response by freshwater ecosystems to a changing climate can be described in terms of three interrelated components: water quality, water quantity or volume, and water timing. A change in one often leads to shifts in

1804-407: The topsoil; 125 million acres [506,000 km ] of land now in crops are rapidly losing topsoil. This can lead to large-scale desertification , permanently transforming a formerly productive landscape into an arid one that becomes increasingly intensive and expensive to farm. The Soil Conservation Service worked with state governments and universities with established agriculture programs, such as

Toolibin Lake - Misplaced Pages Continue

1848-657: The underlying underground water. The original source of almost all fresh water is precipitation from the atmosphere , in the form of mist , rain and snow . Fresh water falling as mist, rain or snow contains materials dissolved from the atmosphere and material from the sea and land over which the rain bearing clouds have traveled. The precipitation leads eventually to the formation of water bodies that humans can use as sources of freshwater: ponds , lakes , rainfall , rivers , streams , and groundwater contained in underground aquifers . In coastal areas fresh water may contain significant concentrations of salts derived from

1892-547: The use of cover crops . The proper combination of such farming methods can be determined by various climatic and soil conditions of that given area. Farming sites are often classified into five levels: insensitive, mild, moderate, high, and extreme, depending on the region's soil sensitivity. Contour farming is applied in certain European countries such as Belgium, Italy, Greece, Romania, Slovenia, and Spain in areas with higher than 10% slope. P. A. Yeomans ' Keyline design system

1936-461: Was constant recharge with little variation with precipitation; in most sites (arid, semi-arid, humid), annual recharge increased as annual precipitation remained above a certain threshold; and in complex areas down to 0.1 aridity index (focused recharge), there was very inconsistent recharge (low precipitation but high recharge). Understanding these relationships can lead to the development of sustainable strategies for water collection. This understanding

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