Evaluation of the Restorative Effect of Three Organic Manures in Rill and Gully Eroded Soil Using Amaranthus hybridus L. as Test Plant

Abstract

The effect of organic manure in restoration of rill and gully eroded soil using Amaranthus hybridus as a test plant was carried out. The aim of this research work was to compare the restorative potentials of cow-dung, goat-dung, and poultry-manure amendment on rill and gully eroded soil. The experiment was laid out in a randomized block design (RBD) with five treatment replicated thrice. Seeds of Amaranthus hybridus were sown directly into the bags and were thinned to two seedlings per bag a week after germination. Soil analysis of the treated samples and control was carried out after six weeks to determine the amount of organic carbon, soil pH, potassium, phosphorus and nitrogen. Also soil particles analysis was carried out to determine the amount of sand, silt, clay and bulk density. Stem height of A. hybridus, leaf area, number of leaves per plant and stem girth were the parameters monitored on a weekly basis. The data collected were subjected to analysis of variance (ANOVA) and least significant difference (LSD) was used to separate the differences among treatment means. The result showed that goat-dung recorded highest organic carbon content of (1.88 and 1.63) respectively in both rill and gully eroded soil samples. Poultry-manure recorded increase in nitrogen content of (0.92 and 0.84) respectively in both rill and gully eroded soil samples. The combination of goat-dung, poultry-manure and cow-dung recorded the highest pH value of (5.90) in rill eroded soil samples while goat-dung recorded the highest pH value of (6.40) in gully eroded soil samples. The least reduction in bulk density in rill soil sample was recorded in goat-dung with value of (1.41) while poultry-manure recorded the least reduction in bulk density of (1.48) in gully eroded soil sample. Percentage clay content recorded highest in control with value of (34.0 and 48.0) respectively in both rill and gully eroded soil samples. The combination of cow-dung, goat-dung and poultry-manure recorded the highest plant height of (21.02cm and 18.10cm) respectively, stem girth (1.36cm and 2.76cm) respectively, leaf area (10.81cm2 and 16.84cm2) respectively in both rill and gully eroded soil sample, in control plant height of (5.64cm and 3.63cm) respectively, in stem girth (0.42cm and 0.32cm) respectively, in number of leaves (7.33cm and 8.33cm) respectively, in leaf area (2.11cm2 and 1.55cm2) respectively recorded  the least value in both rill and gully eroded soil samples. Analysis of variance showed significant difference among the treatments and within the weeks.