Nutrients in wet soil vs. dry soils around seeps

Lori Fisher and Lotoya Austin


We wanted to find out if soil where water is seeping out of the ground had less nutrients because of the constant movement of water through the soil.

We collected samples along a trail on the east side of the valley where water seeps from a number of underground springs.  We identified three localities, each containing wet soil because of a seep partly surrounded by dry soil.  In each locality, we took three samples from the wet soil and three samples from surrounding dry soil, making a total of 9 wet and 9 dry samples.  We first removed all debris from each sample area then took samples from four inches below the surface of the soil.  All samples were collected in individual ziplock bags and labeled with their area and sample number.  The bags were then placed in a drying oven to remove all moisture then analyzed for phosphate, nitrate, and potassium using LaMOTTE Company soil NPK kits #5880.

                We found no detectable nitrate in any of the samples.  Means of phosphorus and potassium differed between wet and dray samples, but since margins of error overlapped, the differences were not statistically significant and we cannot conclude that wet and dry soils differ in phosphorus or potassium content.