Part 1 of Essay
Salinity in both the rivers and on the land is one of the main and most costly results of overclearing and irrigation. Salinity is caused by changes in the delicate balance between surface water and groundwater systems. A small increase in the infiltration of water from the topsoil to the groundwater, due to rainfall or ir ....

Part 2 of Essay
.... crust of salt crystals on the land. Most plants cannot tolerate the scalding chemical effect of the salt, and so they die. As they die off, the soil succumbs to erosion and a double dose of salt and sediment enters nearby rivers and wetlands. In cattle-grazing areas, the animals often gather at saline seeps to lick the salt, which leads to further erosion. Salinity affects around 560,000 hectares of the Murray-Darling basin's most productive irrigation lands, mostly in southern New South Wales, and northern Vict ....