The impacts of pan quarrying on livestock watering in a semi arid region: case study of Kang pan in the Kalahari, Botswana

Abstract

Scenes of mass death of livestock inside a quarry and on the surrounding pan floor prompted this investigation on the impact of quarrying on livestock watering in the semi arid Kalahari region in southwest Botswana. This investigation was carried out at the Kang Pan at the end of the dry season when the water supply situation was at its worst. Samples of stagnant water from the quarry pit that form the major imprint of pan quarrying were collected for analysis of As, Ca, Cu, EC, Fc, Hg, K, Mg, Na, Pb, pH, TDS, and Zn in order to determine the pit water quality. The results show that the quarry pit water at the end of the dry season is highly concentrated not only with salts but also with solids and heavy metals including arsenic, lead and mercury. The water quality parameters are far below the internationally recommended standards for livestock watering. The extremely poor quality of the water collected in the pit is detrimental to livestock health and the pit itself is an environmental hazard to the animals. Pan quarrying without considering the possible environmental impacts has exacerbated loss of livestock in the area arising from severe drought. This, in turn, has affected the livelihoods of the communal farmers.