Salinity is a major environmental issue in Australia. Salinity describes the salt content of water or soil. When the salt content rises to an extreme, it degrades the water quality and land efficiency. This is the problem that is being faced in Australia; salt levels are becoming so extreme that is affecting plant and animal survival, thus damaging infrastructure. Dryland salinity is caused when the rising water-table surfaces natural salts in the soil. The salt remains in the soil and becomes increasingly concentrated as the water evaporates or is used by plants (Australian Government, 2001). One of the main causes for rising water-tables is the removal of the native Australian vegetation. They have deeper roots and use more water than the crop plants that are replacing them. The crop plants have short roots and cannot absorb as much water as the native plants, therefore causing the water-table to rise and bring salt to the surface. Dryland salinity is having detrimental effects on Australia. There is a continuing loss of productive farmland; degradation of soil and water resources; extinction of native plant and animal species and social and economic decline of rural communities. There are many approaches to confronting Australia's salinity problem, but there is not a universal solution that would be practical everywhere.
Salt is a natural feature of the Australian landscape. Until European settlement, the salt remained deep in the soil below the root zone of the native vegetation. The clearing of the natural vegetation results in the slow release of these salts to the soil surface or to the river system, which causes a dramatic increase in the salt concentration of the river flow (Anonymous, 1979). Deep rooted native vegetation tended to use most of the rainfall that it received. However the shallower rooted crop plants that are replacing the native vegetation does not use all the rainfall that it receives, causing the excess rainfall to seep deep down...
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