Soil spatial variability in some soil physical properties for some soil series in East Gharaf lands/Iraq Nadhum Shamkhi Rahal Kut technical institute

Abstract

The study was carried out in East Gharaf land ,Which is situated south east of Kut city ( N 32̊ 18ˉ 00˭ to 32̊ 18ˉ 20̊ ;N32̊ 18ˉ 23˭ to 32̊ 18ˉ 44˭ and E45̊ 15ˉ 18˭ to 45̊ 15ˉ 43˭ ;E 45̊ 14ˉ 57˭to 45̊ 15ˉ22˭ ) of 96.06 hectares area ,the parent material of the soils is an alluvium of Tigris and Euphrates rivers and irrigation deposits of the ancient and recent irrigation practices. The study aimed to analyze and characterize the spatial variability of some physical soil properties of some soil series in Gharaf land .Seven soil series were recognized and classified according to USDA soil Taxonomy and Al-agidi proposed soil classification of Iraqi alluvial soils systems (MM11,MM5,MF11,Mp11,Dp127,Mp12,MM3). Results were statistically analyzed using analysis of variance and least significance deference at a significant level (ρ=0.05) ,and descriptive statistics (minimum ,maximum,mean standard deviation ,coefficient of variation, skewness and kurtosis to measure and characterize horizontal and vertical soil spatial variability. Results showed that ,soils of Gharaf lands reveal spatial variability in their physical properties in both directions (horizontal and vertical).The most variable property was sand (c.v.=134.0%) and the least was Bulk density (c.v.=3.6% and 1.5%-3.5% ) in both directions. And, C2 horizon was the most variable in sand particles and A horizon was the least variable horizon then C1 was in between, accordingly, we strongly recommend a detailed studies have to be done to analyze and characterize soil spatial variability of these soils in order to delineate site- specific soil management units for precise and sustainable agriculture to gain high crop yield.