Determination of the water holding characteristics of agricultural soils that are irrigated from the Bakirçay where the coal washing water is discharged

This study was carried out in order to determine the water holding characteristics of agricultural soils that are irrigated from the Bakırçay where the coal washing waters are discharged and that found in Soma district in Manisa province. In this study, organic carbon analysis and grain size distribution (texture) analysis done and by applying different tensions (pF0, pF1.0, pF1.5, pF1.8, pF2.0, pF2.54 and pF4.2) to the soils, the water holding characteristics (pF curves) of the soil is resulted and the relationships between the organic carbon and texturing are revealed, with the moisture contents of these soils were determined. According to the values obtained from the analyses made at the end of the study, clay, silt and sand contents of the soil were found between 20-60 %, 14-44 % and 24-52 % respectively. However, organic carbon (OC) values ranged between 1.10-19.90 %, while the moisture % ranges under the tensions of pF0, pF1.0, pF1.5, pF1.8, pF2.0 were changed between 18.14-37.54 %, 17.58-34.10 %, 16.99-32.54 % , 16.56-28.04 % and 15.66-25.47 % respectively. Moisture content in field capacity (pF2.54) and wilting point (pF4.2) were changed between 14.01-24.25 % and 12.13-22.11 % respectively. According to the results obtained from the regression analysis, it has been determined that, 29 soils samples irrigated with coal washing waters that put under different tensions (pF0, pF1.0, pF1.5, pF1.8, pF2.0, pF2.54 ve pF4.2) it was found that there is a positive correlation between % moisture values and % organic carbon contents, and that this relationship is significant at P<0.01 level.