THE EFFECT OF THE SEDIMENTS OF THE HILLA RIVER ON THE CHARACTERISTICS OF THE ADJACENT SOILS (BABYLON GOVERNORATE)

Abstract

This study was conducted to investigate the effect of the sediments of the Hilla River on the characteristics of some the sedimentary soils adjacent to the Hilla River, the sampling sites were chosen in the study area along the eastern side of the Hilla River, which extends from the beginning of its branching from the Euphrates River at the front of the Hilla dam in the province of Babil and along the river in the south, all the way to the back of the Sadr alDaghara regulator, which is located between the provinces of Babel and Al-Diwaniyah. Fifteen pedons were excavated, distributed in five transects perpendicular to the Hilla River. Each transect contains three pedons and represents a unit of shoulder, basin and depression. The results of soil investigations showed that there is a difference in some soil morphological properties among the studied sites according to the shape of the land, it was noted that there was no difference in the Hue through the wavelength of the studied sites and it was 10YR, with a difference in the Value and Chroma among all the pedons of the study area with depth, and indicates that the same sedimentation source (River Hilla). The predominance of the two types of blocky structures (angular blocky and sub angular blocky) and this shows the effect of the type of sediment. The results of the physical analysis showed a variation in the soil texture for both vertical and horizontal directions with the predominance of silt and sand particles and a decrease in the percentage of clay particles and this depended on the sedimentation speed associated with the proximity or distance of the river. As for the bulk density, its values also have changed as a result of a variation in the volume distribution ratio of soil particles of sand, silt and clay. While the results of the chemical analysis indicated that there is a difference in the chemical properties of soils in all study transects with depth, pH values lie between neutral to moderately basic (6.85-8.19) within the normal range of Iraqi soils, the electrical conductivity ranged between (0.68-36.2 ds m-1) from low salinity soils to very high salinity soils. As for SAR, it was low in sodium in most of the study pedons with depth, reaching 2.35, (medium to very high in some sites), and the values of the CEC ranged between (7.49- 21.45) Cmol Kg-1, As for the soil content of total calcium carbonate (CaCO3), whose values ranged between (6.52-22.17)%, the highest value of the soil content of organic matter reached in most of the surface horizons compared with the subsurface horizons