Very well said Anicet. No change in soil EC across depth means , displaying utmost stability in soil physical , chemical and biological properties of the soil profile , considering the control section of the profile , you are considering...
The absence of EC variability over 2 m section of your soil suggests that the physical, chemical and even biological properties like water content, porosity, dry density, clay fraction, temperature, etc, within that soil zone are almost uniform. It may not exclusively imply that these properties are homogeneous but within the sensivity limit of the instrument used in the measurement, you can conclude that the soil zone is homogeneous. Actually this type of situation uncommon because differences in activities in the upper 40 cm soil layer and deeper layers could have causes some changes in EC observations. It is strongly advised that you repeat the measurements with another instrument if possible.
Anthony is correct and the value you report is also very low, so unless the soil is very highly leached, this may indicate an instrumentation problem. Check the calibration or do a measurement on a soil that you know has a higher EC.
Yes the value 1µS/cm constant across 2 m soil section is too low. Imran, Please tell us how you measured EC and what are the main properties of your soil. See the attached paper for an example of EC variations in different soils from USA. Best wishes
Yes , the EC value is really too low. And soils around Kanpur are mostly salt affected where salinity coupled with sodicity is the major issue, infact the epicentre of salinity/sodicity in india. I wonder at the exceptionally low value of EC.
Anicet , i am placing some clues of the soil from Kumaon himalayas. Soils of summits/ridge tops and side/reposed slopes are mainly shallow to medium deep, coarse textured, underdeveloped/partially developed having A-C horizons (Entisols) followed by deep, fine textured and comparatively developed soils (Inceptisols). Soils of river valleys and piedmont plains are mainly medium deep to deep, loam to clay loam with structural B horizon and belong to Inceptisols followed by Entisols. Soils of summits/ridge tops contain more SOC stock in comparison to other physiographies. Soils must nearly neutral with much higher level of DTPA-Fe and Mn ( PDF enclosed for further reference ) with most of the horizons having EC between 0.10 and .0.18 dS/m.
Soil EC can also be an effective way to determine the texture of the surface layer because smaller clay particles conduct more electrical current than larger silt and sand particles. Probabaly , your quarry has more relevance with this sentence , of i am not wrong ..Likewise ,soils that consist dominantly of clay minerals that have a high cation-exchange capacity (CEC), such as smectite, can have higher EC than soils that consist dominantly of clay minerals that have a low CEC, such as kaolinite. So , depending upon origin of loess soils , soil EC will preferably be 01.10-0.15 dS/m from non-saline soil sites . Two very good PDFs are enclosed better understanding on the on-going issue..