African Journal of Soil Science

African Journal of Soil Science ISSN 2375-088X Vol. 11 (2), pp. 001-014, February, 2023. © International Scholars Journals

Full Length Research Paper

Determination of climate parameters effect on soil carbon fluxes along the north-south moisture gradient in the kalahari ecosystem

M. Bitsang1, O. Dikinya1, B. G. Moganane1 and B. Mosetlhi1

1Department of Environmental Science, University of Botswana, Private bag 00704 Gaborone, Botswana.

Accepted 17 May, 2019


Temperature and rainfall patterns have globally, regionally and locally changed. At global and regional level, temperature and rainfall are dominant factors affecting soil organic storage and that carbondioxide emissions increases with increasing rainfall and decreasing temperature. The objective of this study was to determine “in situ” the effects of temperature and rainfall on soil carbon emissions in the Kalahari, south west of Botswana. Data on temperature and rainfall for a period of 35 years were collected for trend analysis. Six sites were selected across different land use zones in the area to measure soil CO2 emissions. Results indicated a trend towards an increase in mean annual temperatures and for rainfall, the extreme southern part of the study area is becoming wetter and in the north a moderate trend towards a decrease was observed. CO2 emissions were significantly (p<0.05) higher at watering sites and declining with distance in both the wet and dry seasons. Wet season emissions were significantly higher (64.50 µmol/m2/s) than during the dry season (4.72µmol/m2/s). Findings showed that the region is experiencing the impact of climate change and variability. Temperature and rainfall are the major factors affecting soil carbon emissions in the Kalahari ecosystem.

Keywords: CO2 emissions, land use, Kalahari, temperature and rainfall.