Level soil bunds (LSB) and stone bunds (SB) have been widely implemented in the Bokole watershed since 2000 through support of the World Food Program (WFP). However, the performance of them against the target of the s...Level soil bunds (LSB) and stone bunds (SB) have been widely implemented in the Bokole watershed since 2000 through support of the World Food Program (WFP). However, the performance of them against the target of the structure has not been studied. This study analyzed the effect of LSB and SB on selected soil properties, when compared with nonterraced cropland. The Bokole watershed was divided into two units. From upper watershed, three croplands with LSB (aged 4, 6, and 9 years) and three nonterraced croplands each adjacent to one of the LSB were selected. Similarly, in lower watershed, SB aged 4, 6, and 8 years and three nonterraced croplands each adjacent to one of the SB were selected. From each cropland with LSB and SB, three composite soil samples (rep licates) were collected systematically in X designed rectangular plot. From each nonterraced cropland, three composite soil samples (replicates) were collected in X designed square plot. A total of 36 soil samples were analyzed for Soil Organic Carbon (SOC), Total Nitrogen (TN), Available Phosphorus (AP), Available Potassium (AK), pH, and Cation Exchange Capacity (CEC) following standard laboratory procedures. Most soil parameters were not significantly different in cropland with LSB and SB compared to nonterraced. However, in LSB aged 4 years and SB aged 6 years AP and pH were significantly less than their adjacent-nonterraced cropland. In SB aged 8 years, SOC, AP, AK, and pH were also significantly less than adjacent-nonterraced cropland. Past erosion, and past land uses are likely factors contributed to the observed result. It was inferred that the mean con tribution of LSB and SB alone for crop production with regard to analyzed soil parameters was not significant in the considered sites. Additional soil fertility management practices should be incorporated for better effect.展开更多
Soil erosion is a major environmental problem affecting development endeavor.Physical soil and water conservation(SWC)measures such as soil bunds are implemented to mitigate soil erosion.However,information on the eff...Soil erosion is a major environmental problem affecting development endeavor.Physical soil and water conservation(SWC)measures such as soil bunds are implemented to mitigate soil erosion.However,information on the effects of soil bunds on soil fertility is limited.This study was aimed to evaluate soil quality in fields with soil bunds and with no soil bunds in steep,middle and lower sloping cultivated lands as well as spatial variation of soil properties in between bunds in southwest Ethiopia.About 7-15 years old bunds and nearby cultivated fields lacking bunds were assessed.From 0 cm-20 cm soil depth,a 36 soil samples were collected.Soil texture,soil organic carbon(SOC),total nitrogen(N_(tot))and exchangeable potassium(K_(exch))were analyzed.Soil bunds showed significantly(p<0.0.5)greater clay but less sand than adjacent no-bund fields.In steep,middle,and lower slopes,concentrations of SOC and Kexch were greater in fields with soil bunds than without.Lower slope fields showed greater clay,SOC and nutrients than steep slopes.In between soil bunds,soil was more fertile at above bunds than below the bunds.In Fanta watershed,soil bunds are vital conservation measure to retain soil fertility on cultivated mountainous area.展开更多
文摘Level soil bunds (LSB) and stone bunds (SB) have been widely implemented in the Bokole watershed since 2000 through support of the World Food Program (WFP). However, the performance of them against the target of the structure has not been studied. This study analyzed the effect of LSB and SB on selected soil properties, when compared with nonterraced cropland. The Bokole watershed was divided into two units. From upper watershed, three croplands with LSB (aged 4, 6, and 9 years) and three nonterraced croplands each adjacent to one of the LSB were selected. Similarly, in lower watershed, SB aged 4, 6, and 8 years and three nonterraced croplands each adjacent to one of the SB were selected. From each cropland with LSB and SB, three composite soil samples (rep licates) were collected systematically in X designed rectangular plot. From each nonterraced cropland, three composite soil samples (replicates) were collected in X designed square plot. A total of 36 soil samples were analyzed for Soil Organic Carbon (SOC), Total Nitrogen (TN), Available Phosphorus (AP), Available Potassium (AK), pH, and Cation Exchange Capacity (CEC) following standard laboratory procedures. Most soil parameters were not significantly different in cropland with LSB and SB compared to nonterraced. However, in LSB aged 4 years and SB aged 6 years AP and pH were significantly less than their adjacent-nonterraced cropland. In SB aged 8 years, SOC, AP, AK, and pH were also significantly less than adjacent-nonterraced cropland. Past erosion, and past land uses are likely factors contributed to the observed result. It was inferred that the mean con tribution of LSB and SB alone for crop production with regard to analyzed soil parameters was not significant in the considered sites. Additional soil fertility management practices should be incorporated for better effect.
文摘Soil erosion is a major environmental problem affecting development endeavor.Physical soil and water conservation(SWC)measures such as soil bunds are implemented to mitigate soil erosion.However,information on the effects of soil bunds on soil fertility is limited.This study was aimed to evaluate soil quality in fields with soil bunds and with no soil bunds in steep,middle and lower sloping cultivated lands as well as spatial variation of soil properties in between bunds in southwest Ethiopia.About 7-15 years old bunds and nearby cultivated fields lacking bunds were assessed.From 0 cm-20 cm soil depth,a 36 soil samples were collected.Soil texture,soil organic carbon(SOC),total nitrogen(N_(tot))and exchangeable potassium(K_(exch))were analyzed.Soil bunds showed significantly(p<0.0.5)greater clay but less sand than adjacent no-bund fields.In steep,middle,and lower slopes,concentrations of SOC and Kexch were greater in fields with soil bunds than without.Lower slope fields showed greater clay,SOC and nutrients than steep slopes.In between soil bunds,soil was more fertile at above bunds than below the bunds.In Fanta watershed,soil bunds are vital conservation measure to retain soil fertility on cultivated mountainous area.
