Mass–height profile and total mass transport of wind eroded aeolian sediments from rangelands of the Indian Thar Desert

Abstract

Abstract Wind erosion is an active land degradation process in the Indian Thar Desert and severe dust storm events during hot summer months in the region are very common. Assessment of soil loss due to dust storm events from major land use systems of the Indian Thar Desert is highly essential for proper environmental planning. Characterization of the mass–height profile of wind eroded aeolian sediment is an important step to compute soil loss/mass transport but was not previously studied in the region. In the present study, aeolian mass fluxes (kg m −2 ) at different heights from soil surface were measured at two major rangelands in the Indian Thar Desert: Overgrazing rangeland at Jaisalmer (26°55′N and 70°57′E), and controlled grazing rangeland at Chandan (27°01′N and 71°01′E). Evaluation of several mass–height profile models revealed that a power decay function [ q ( z ) = a z − b , where q ( z ) is the measured mass flux at an height of z (m) from soil surface; a and b are parameters of the equation] was best to characterize the mass–height relationship of aeolian sediments from the Indian Thar Desert. The average mass transport rate (kg m −1 day −1 ) or the total soil loss during hot summer months was significantly higher at the overgrazed rangeland site than at the controlled grazing rangeland site. Therefore, protection of existing rangelands, which comprise about 80% geographical area of the Indian Thar Desert may check the land degradation process due to wind erosion.