Variation of Soil Properties with Water Saturation in a Swale

This research examines the effects of water saturation on soil properties in a swale located in an urban nature preserve.  Soil textural analysis, measurement of soil horizons, depth to parent material, and examination of soil color are compared within the swale and away from the swale.  Soil color and soil horizonation are the product of soil-forming factors: climate, topography, parent material, biological activity, and time.  The hypothesis is that soil that develops under intermittent saturated conditions within the swale will have different physical properties compared to soil located away from the swale.  Representative soil samples were taken using a soil probe, at intervals lengthwise along the swale and along several transects across the swale.  Soil samples were examined for hydric soil indicators, including soil color (described using Munsell colors) and variations in soil texture (evaluated using the field method of textural analysis).  Parent material was identified by acid reaction of calcium carbonate, found in the parent glacial till.  Standard surveying techniques were used to create a topographic map of the area, and soil characteristics were mapped to show relationships of soil properties to the location of the swale.  Gley, a dark blue soil color resulting from conditions of water saturation, was noted in soils within the swale, but not to the degree expected in soils that develop under conditions of constant saturation.  Farther away from the swale, no gley colors were present.  A map of results shows the extent of influence of water-saturated conditions on soil development near the swale.