Abstract:
This study was carried out in Kulkullessa Sub-Watershed of Goro Gutu District in Eastern
Ethiopia to assess the effects of climate smart SWC practices and slope gradient on selected
physicochemical properties of the soil and the soil's organic carbon stocks. The farmland
conserved by SB, BT and GS five years after construction with two slope gradients (15-20%)
and (21-30%) was selected. Twenty-four composite soil samples were collected from a depth of
20 cm and tested in the Haramaya University soil laboratory. The result was analyzed with the
statistical software SPSS Version 20. The study found that climate smart SWC practices were
very effective on soil physicochemical properties and SOCS of the study area. Similarly, the
slope gradient was brought considerable variation on soil physicochemical properties and soil
organic carbon stock. More amount of clay and lower sand were recorded on conserved
farmland and situated on lower slope gradient. The lower value of BD was recorded on
farmland conserved by bench terrace. The recorded value for total porosity on the farmland
conserved by BT was also positively higher and significant (p ≤ 0.05). The higher value for EC
and lower pH value were recorded on conserved farmlands, which were significant (p ≤ 0.05).
In addition, SOM content and TN were exhibited highest values on the farmland conserved by
stone bund. Further, climate smart SWC practices were found effective on increasing the value
of exchangeable bases on farmlands of the study area. In addition, CEC has been positively
influenced and significant (p ≤ 0.05) on farmland conserved by SB and bench terrace. Likewise,
the higher mean values for micronutrients and SOCS were recorded on farmlands conserved by
SB, BT and GS in contrast to the value recorded on NCF of the study area. In general, climate
smart SWC practices were resulted in outstanding potential for improving the agriculturally
and environmentally sound physicochemical properties of the soil and organic carbon stock
