Classification of Arid & Semi-Arid Areas: A Case Study in Western Australia

AbstractGroundwater is one of the most important water sources in arid and semi-arid areas. With the increasing world population and the water demand for agriculture and urban use, the need for water resources has increased, especially in arid and semi-arid regions, where groundwater resources play a significant role. To prevent the pollution of groundwater resources, various studies for their preservation and maintenance should be carried out, including a detailed plan for proper management of water resources and establishing a balance between water quality and how to use them. It becomes important to understand the spatial change of the quality of groundwater resources. In this study, Sabzevar plain, a typical region of semi-arid climate in Iran, was selected as a case study to assess the groundwater quality of the region, using data from 24 observation wells between 2015 and 2019. Using Arc GIS software, a map of groundwater quality parameters in the study area was prepared for quality assessment and comparison with existing international standards. The results showed that (except pH and HCO3−) the concentration of Sodium, Magnesium, and other anions and cations is higher than the corresponding WHO standard limit, suggesting that the study area is unsuitable for drinking and agricultural use. According to the Wilcox chart, 87.5% of the samples are in the C4S4 class while 8.33% are in the C4S3 class, showing the groundwater unsuitable for agricultural use due to its high salinity and alkalinity. Piper diagrams show that more than 50% of the samples are non-carbonate alkalis, indicating a very high salinity in the area. According to the pie chart, chlorine ion and sodium ion are the dominant anions and cations in the Sabzevar plain, respectively. The Schuler diagram shows that none of the samples examined were in a good class for drinking. Therefore, considering the importance of water for agricultural activities in the study area, it is recommended to have agricultural management solutions to prevent groundwater mixing with freshwater resources.

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The Distribution of Red Kangaroos in Relation to Range Regeneration.

The Rangeland Journal ◽

10.1071/rj9930003 ◽

1993 ◽

Vol 15 (1) ◽

pp. 3 ◽

Cited By ~ 10

Author(s):

GL Norbury ◽

DC Norbury

Keyword(s):

Western Australia ◽

Local Area ◽

Arid Areas ◽

Radio Tracking ◽

Control Programs ◽

Local Populations ◽

Native Shrubs ◽

The Impact ◽

Widespread View ◽

Semi Arid

Pastoralists frequently claim that attempts at range regeneration in arid and semi-arid areas are thwarted by kangaroos. This paper examines the possibility that the impact of kangaroo grazing is exacerbated by an influx of kangaroos onto regeneration sites. The amount of kangaroo dung in a 7500 ha paddock in arid Western Australia increased six-fold over a 15-month period following the removal of sheep. A similar influx was apparent in another destocked paddock that provided unusually high offtake of kangaroos by a commercial shooter. The amount of kangaroo dung remained relatively stable in a control paddock that was stocked. Some areas subject to cultivation and reseeding with native shrubs also showed increased amounts of kangaroo dung, indicating relatively intense kangaroo grazing. Radio-tracking of 46 kangaroos showed them to be mostly sedentary, suggesting that 'invading' kangaroos emerge from the local area. This conclusion is contrary to the widespread view that kangaroos migrate from distant locations. Thus, kangaroo control programs on sensitive areas are likely to be long-lasting because incursions are predominantly from local populations.

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