JavaScript is disabled for your browser. Some features of this site may not work without it.
| dc.contributor.author | Birihan, Simir | |
| dc.date.accessioned | 2020-03-19T10:44:11Z | |
| dc.date.available | 2020-03-19T10:44:11Z | |
| dc.date.issued | 2020-03-19 | |
| dc.identifier.uri | http://hdl.handle.net/123456789/10741 | |
| dc.description.abstract | Land degradation by soil erosion and its induced threat is a serious problem in the world specifically in northwestern Ethiopian highland. To control this adverse impact different soil and water conservation (SWC) practices were implemented in the food for work program through government-led and with the help of NGOs. However, there is no substantial scientific research on the effects of SWC practices on hydrological responses. In this study, two watersheds that are situated in the northwestern Ethiopian highland were selected. One has sufficient SWC practices since 2012 with a total drainage area of 87.6ha and the second one has limited conservation practices with a total drainage area of 234.7ha. The adjacent watersheds are comparable in their overall characters of geology, soil type, climate, and relief. The treated and the untreated watersheds have an average slope of 8.90 and 9.40 respectively. The study was conducted by installing rectangular cross-sectional weir on the treated and staff gauge on the untreated watershed. Data of Rainfall, Streamflow, Sediment Concentration, and Sediment-associated and Dissolved nutrient of N and P for 2015 and 2016 rainy periods were collected. The watersheds received an annual rainfall of 665 mm in 2015 and 795 mm in 2016. The median infiltration rates for treated and untreated watershed were 22 mm hr-1, and 19 mm hr-1 respectively. The runoff responses from treated watershed were 8.5 mm yr-1 for 2015 and 9.6 mm yr-1 for 2016. This is lower than untreated watershed which responded17.3 mm yr-1 for 2015 and 15.3 mm yr-1 for 2016. The implemented conservation practices had a capacity of enhanced base flow in the treated watershed as compared to the untreated watershed. The runoff coefficients of the treated and untreated watersheds were nearly 0.04 and 0.1 in both periods of 2015 and 2016 respectively. The runoff and base flow were higher in 2016 than 2015. This is due to the higher rainfall were recorded in 2016. This figure shows that the implemented SWC practices reduced the runoff responses by two fold. Similarly, the practices reduced sediment yield from treated watershed, which delivered 2.4 ton ha-1yr-1 and 2.1 ton ha-1yr-1 for 2015 and 2016 of the rainy period respectively. This is lower than the untreated watershed that lost 6 ton ha-1yr-1 and 8.5 ton ha-1yr-1 in 2015 and 2016 respectively. The adopted SWC activities able to reduce the sediment yield by reducing the runoff volume and trapping the soil losses. The difference between runoff volume and sediment yield within the two watersheds were statistically significant at 5% significance level. This study examined that SWC practices can diminish soil and essential nutrient losses. However, it is important to investigate the long-term effects of SWC in the reduction of soil and nutrient losses. | en_US |
| dc.language.iso | en | en_US |
| dc.subject | Hydraulic and Water Resources Engineering | en_US |
| dc.title | EFFECTS OF SOIL AND WATER CONSERVATION PRACTICES ON HYDROLOGICAL RESPONSES IN ALEKT WENZ WATERSHED NORTHWESTERN ETHIOPIAN HIGHLAND. | en_US |
| dc.type | Thesis | en_US |
