Climate, soils and natural vegetation of Rajasthan MCQ - Practice Questions with Answers

Rajasthan's rainfall pattern is not explained by saying that the Aravalli simply blocks all clouds. The range runs roughly south-west to north-east and is broadly parallel to the Arabian Sea branch of the south-west monsoon. Because winds move along the range rather than being forced sharply upward across it, the western side receives weak orographic rain. Thus the assertion about weak orographic rainfall in western Rajasthan and the reason about Aravalli alignment are both true, and the alignment explains the rainfall pattern.

Keoladeo Ghana in Bharatpur is described as a wetland National Park, Ramsar site and UNESCO World Heritage Site, and as an important bird habitat. It should not be confused with desert habitat. The desert habitat example is Desert National Park in Jaisalmer and Barmer, especially linked with the Great Indian Bustard, also called Godawan. Sambhar Lake as a saline wetland and Khejarli as the 1730 Bishnoi conservation site are both supported facts.

Soil properties are linked with region and formation process. Desert soils dominate western districts such as Jaisalmer, Barmer, Bikaner and adjoining areas; they are sandy, light-coloured, low in humus and weak in water-holding capacity. Black soils belong mainly to the south-eastern Hadoti belt, especially Kota, Bundi, Baran and Jhalawar, and their clayey nature gives good moisture retention. Red soils are instead associated with Dungarpur, Banswara and parts of Udaipur, Chittorgarh and Rajsamand, where iron-rich weathering gives the colour. Therefore the desert-soil and black-soil statements stand, while the red-soil statement fails.

The vegetation pattern in Rajasthan follows the rainfall gradient. Tropical thorn vegetation dominates the arid and semi-arid west and centre, with hardy species such as khejri, rohida, kair, babul and ber. Dry deciduous vegetation becomes more common in the relatively wetter Aravalli, southern Rajasthan and Hadoti tracts, while Mount Abu is a wetter and more forested hilly pocket. The statement that dense humid forests dominate the western desert because rainfall is high there contradicts this pattern, so it is the incorrect statement.

There is a simple regional grid for Rajasthan's soils: the west is sandy, Hadoti is black soil, and the eastern plain is alluvial. Sandy desert soil is linked with dry western districts such as Jaisalmer, Barmer and Bikaner. Black cotton or regar soil belongs to the Hadoti plateau of Kota, Bundi, Baran and Jhalawar. Alluvial soil is associated with the eastern plain and river-fed belts connected with rivers such as Banas, Banganga and Chambal.