1. Enzyme Activity in the Hyporheic Region of Piedmont Streams
EC Fellow: Danielle Whitman
Mentor: Dr. Janet MacFall
Environmental Studies
Elon University
Methods
Five major enzymes involved in soil biogeochemical cycling will be examined to see if there is any significant difference between activity in eroded and non-eroded soils. This will be measured using colorimetric assays assessed by spectrophotometry.
Biogeochemical Cycling
Biogeochemical cycles are the pathways by which a chemical element or molecule required by life moves between the living and nonliving parts of the environment. Some examples of these include the carbon, phosphorus, and nitrogen cycles.
Figure 2. Diagram of Hyporheic Zone (Alley et al., 2002).
What is the hyporheic zone?
The hyporheic zone is the site of dynamic exchanges of water and materials between the ground water and surface water (Figure 2), where the soil remains saturated (Boulton, 2000). Due to the interactions that occur within the hyporheic region, this area has great biological and chemical activity.
Figure 1. The Phosphorus Cycle (Raven & Berg, 2001)
Figure 4. Preparing samples to test.
Primary Question
Does enzyme activity of piedmont hyporheic soils differ between eroded and non-eroded sites?
Enzymes as Indicators of Health
Extracellular enzymes secreted from bacteria can be found free in soil solution and are the primary enzymes that facilitate biogeochemical cycling (Burns & Dick, 2002). Enzymes have great potential to determine microbial functioning and processes in soil systems. Several enzymes can be used as indicators for assessing nutrient cycling because of their important role in breaking down organic material (Wright & Reddy, 2001).
References
Alley, W. M., Healy, R. W., LaBaugh, J. W., & Reilly, T. E. (2002). Flow and Storage in Groundwater Systems. Science, 296(5575),
Boulton, A. J. (2000). River Ecosystem Health Down Under: Assessing Ecological Condition in Riverine Groundwater Zones in Australia. Ecosystem Health, 6(2),
Burns, R. G., & Dick, R. P. (2002). Enzymes in the Environment: Activity, Ecology and Applications. New York, N.Y.: Marcel Dekker, Inc.
Wright, A. L., & Reddy, K. R. (2001). Phosphorus Loading Effects on Extracellular Enzyme Activity in Everglades Wetland Soils. Soil Science Society of America, 65,
Figure 3. Collecting a soil sample.