MULCH APPLICATION ON BARLEY GRAIN YIELD AND PHYSICOCHEMICAL PROPERTIES OF SOIL IN NEGELE ARSI DISTRICT, CENTRAL, ETHIOPIA

There is uncertainty about the type of mulch to use to reduce soil nutrient depletion and water loss and at the same time enhance crop yield that will also be influenced by the materials available locally for use and their management. The objective of this study was to investigate the effect of mulch application on barley grain yield and physicochemical properties of soil in Negele Arsi district, Central, Ethiopia. Experimental plots were laid on farmers fields’ in randomized complete block design by taking farmers field as a replication. Five farms of each with a currently mulched plot, a year ago mulched plot with perennial mulch and conventional fields as control (15plots of 10m in width and 20m in length in general) were selected for the establishment of the experiment. Subplots of 1mx1m at each corner and a center of each main plot were used for taking barley grain yield and soil data. A total of 30 soil samples collected from two depth layers: 0–20 and 20–40cm were air-dried and passed through a 2 mm sieve to remove roots, and large organic residues. Soil organic carbon concentration in the soil samples was determined by Walkley and Black method. The soil data were subjected to a two-way ANOVA analysis using the general linear model Procedures of SAS. The pairwise comparison method was also used to assess the mean difference of the treatment types and depth levels depending on soil properties. The average barley grain yield obtained from plots mulched with perennial mulch in 2018 (1.52±0.209kg) was higher than plots mulched in 2017 (1.48±0.135kg) and conventional farmland plots (1.44±.0962kg). The overall mean SOC stock was found to be higher under plots mulched in 2018(49.8291±17.9301) and lower in soils under conventional farm plots (39.1182±13.5183) than another treatment type. The highest overall mean of soil carbon stock under plots mulched in 2018 indicates that perennial mulch might be the remedy for replenishing the declining soil fertility on conventional farmlands and to increase barley grain yield on a sustainable basis. KEYWORDS: conventional farm, grain yield, perennial mulch, soil fertility