Assessment of residual tied ridges and farm yard manure application on sorghum yield in semi-arid areas of Hombolo Dodoma, Tanzania
| dc.contributor.author | Kabanza, Andrew Kaggwa | |
| dc.date.accessioned | 2026-04-28T07:53:29Z | |
| dc.date.available | 2026-04-28T07:53:29Z | |
| dc.date.issued | 2003 | |
| dc.description | Dissertation | |
| dc.description.abstract | Soil physical management involves better understanding of the dynamics of soil physical properties. The reported field study was conducted in semi-arid central Tanzania on a continuing five years old tillage trial comprising No-till (NT), shallow tied ridges (STR), deep tied ridges (DTR) and annually made tied ridges (ADTR) to study the effect of residual unmanured and manured tied ridges on soil physical and hydrological properties as well as sorghum grain yield. Land preparation involved the removal of crop residues from the previous season and a minimum maintenance of the residual tied ridges. The test crop was sorghum variety Tegemeo. Investigated parameters included average residual organic matter (OM) content of the experimental site at different depths. Soil surface roughness before and after field operations and after every heavy rainstorm. Dry bulk density was determined before planting, at mid season and at harvest. Cumulative infiltration was determined before planting and at harvest. Gravimetric moisture content determinations at different depths were made on weekly basis. There was no significant (P<0.05) difference in residual OM content among tillage treatments. The results were that tillage significantly (P<0.05) affected soil surface roughness indices (SSRI) among tillage treatments (NT, STR and DTR). It was 185% high in the residual tied ridges compared to the control. Cumulative infiltration was significantly (P<0.05) higher in NT treatments than in all other six treatments. It was 285.66 mm/hr before planting and 412.83 mm/hr at harvest. STR, DTR and ADTR had intermediate values. Weekly gravimetric soil profile moisture content (mm) in 0-50 cm soil layer were significantly (P<0.05) influenced by treatments throughout the season. It was high in the residual tied ridges compared to the control. Dry bulk density in the surface layer was not significantly (P<0.05) different among treatments. A significant difference in bulk density was observed between treatments only at harvest and within 30-50 cm-soil layer. Farmyard manure had no effect on bulk density. Total porosity values were not significantly different among tillage treatments during the study period. Percentage seedlings emergence and the number of plants at harvest were significantly (P<0.05) higher in DTR. than the other treatments. Sorghum grain yield was significantly (P<0.05) affected by tillage methods. The annually made tied ridges had higher grain yield of 2.17 tons/ha than only 0.42 tons/ha in the control. Grain yield of 1.92 tons/ha under residual tied ridges after five seasons was statistically comparable to the yield from annually made tied ridges. Residual tied ridges can thus be utilized for up to five seasons. The reduced tillage and ridging cost as well as the increased sorghum grain yield under the residual tied ridges is likely to now make the system attractive to farmers in semi-arid areas. | |
| dc.description.sponsorship | Norwegian Agency for Development Co-operation (NORAD) through the Department of Soil Science, Sokoine University of Agriculture, | |
| dc.identifier.uri | https://www.suaire.sua.ac.tz/handle/20.500.14820/7492 | |
| dc.language.iso | en | |
| dc.publisher | Sokoine University of Agriculture | |
| dc.subject | Sorghum yield | |
| dc.subject | Manure application | |
| dc.subject | Residual tied | |
| dc.subject | Semi arid | |
| dc.title | Assessment of residual tied ridges and farm yard manure application on sorghum yield in semi-arid areas of Hombolo Dodoma, Tanzania | |
| dc.type | Thesis |