Comparing Field-Scale Soil Moisture Dynamics of a Reclaimed Surface Mine to Undisturbed Soils.

When soils are reclaimed from surface coal mine activity, an attempt is made to restore soil productivity and original hydrology. Spatial variability of soil catenas provide natural variability in hydrology and hence variability in plant communities. Soils used in reclaimed surface mine sites have been mixed; and therefore, they have lost structural flow paths and other hydrologic characteristics created by soil formation. Differences in soil hydrology of reclaimed fields and undisturbed fields are unknown. This research will attempt to quantify field scale soil moisture differences between a field reclaimed for 12 years and an undisturbed field. Electromagnetic induction (EMI) is a means for mapping soil variability, specifically changes in soil texture and water holding capacity. EMI will be used to map changes in soil moisture through a summer (dry) season as the soil dries and assess the spatial variability in soil moisture regimes. Though it is expected that topography will still drive spatial variability in soil moisture, we hypothesize that soils in the reclaimed field will have more homogeneous distribution of soil moisture, especially during drying, compared to the soils in the undisturbed fields. To test this hypothesis, semivariograms of soil moisture and topography will be used to quantify the relation of soil moisture to topography and spatial structure of soil moisture in each field as soil drying occurs. The shape of variograms, nugget, range, and sill of the fields will be compared over time. This information will be used to better understand field-scale moisture of reclaimed soils and the drying characteristics in relation to an undisturbed field.