Effect of tillage systems and tillage direction on soil hydrological properties and soil suspended particle concentration in arable land in Uganda

Nakiguli Fatumah; Seifu A Tilahun; Ssemwanga Mohammed

doi:10.1016/j.heliyon.2020.e05616

Effect of tillage systems and tillage direction on soil hydrological properties and soil suspended particle concentration in arable land in Uganda

Heliyon. 2020 Dec 1;6(12):e05616. doi: 10.1016/j.heliyon.2020.e05616. eCollection 2020 Dec.

Authors

Nakiguli Fatumah^{1

2}, Seifu A Tilahun³, Ssemwanga Mohammed^{2

4}

Affiliations

¹ College of Natural and Computational Sciences, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia.
² College of Agriculture and Environmental Sciences, Makerere University, P.O. Box 7062, Kampala, Uganda.
³ Faculty of Civil and Water Resources Engineering, Bahir Dar Institute of Technology, Bahir Dar University, P.O. Box 26, Bahir Dar, Ethiopia.
⁴ Agriculture, Environment, and Livelihood, P.O. Box 71257, Kampala, Uganda.

Abstract

The 2030 Agenda for Sustainable Development addressing the issues of environmental degradation has been challenged by human developments and activities. Crop production systems and technologies (e.g. soil tillage) are among the leading factors causing environmental degradation. In this study, the effect of soil tillage systems (i.e. no-tillage (NT); stubble-mulching (SM); deep tillage (DT); and conventional tillage (CT)) on surface runoff volume (SRV), suspended sediment concentration (SSC), infiltration rate (IR), and soil moisture content (SMC) in the common bean (Phaseolus vulgaris L.) farms, Mukono District, Uganda was evaluated. The effect of soil tillage direction on SRV was also assessed. The SRV, SSC, IR, and SMC were monitored under Complete Randomized Block Design (CRBD) experiments with four soil tillage systems in Goma and Kimenyedde experimental sites during two wet seasons. The results showed that SRV, SSC, IR, and SMC were significantly (p < 0.05) influenced by the soil tillage system, season, and site. The highest total SRV was observed during the first season in Goma experimental site under CT with soil tillage along the slope (1071.3 mm). The lowest SRV was observed during the second season in Kimenyedde experimental site under NT (165.0 mm). The highest and lowest mean SSC was observed in the CT (2.41 ± 0.3 g L^-1) in Goma experimental site during the first season and NT (0.43 ± 0.1 g L^-1) in Kimenyedde experimental site during the second season, respectively. The SSL was highest under CT in both Goma (147.17 kg ha^-1season^-1) and Kimenyedde (114.93 kg ha^-1season^-1), and lowest under NT with the means of 11.25 and 9.19 kg ha^-1season^-1 in Goma and Kimenyedde experimental sites, respectively. Both SRV and SSC increased linearly with both rainfall amount (RF) and rainfall intensity at 10 min (RI₁₀). The highest and lowest IR and SMC were observed in the NT and CT treatments, respectively. No significant (p > 0.05) variations were observed in the SMC under the NT and SM treatments. Overall, soil tillage systems, soil type, and rainfall characteristics are among the key factors influencing the magnitudes of SRV and SSC in both time and space. This particular study suggests that NT and SM would help reduce the magnitudes of SRV and SSC, in agricultural fields.

Keywords: Agricultural science; Environmental science; Hydrology; Infiltration rate; Soil moisture content; Soil tillage systems; Surface runoff volume; Suspended sediment concentration; Tillage direction.