Junior Colloquium: Team SWAMP

Mentor: Dr. Dave TilleyLibrarian: Mr. Robert Kackley

Members: Arsh Agarwal, Allie Bradford, Kerry Cheng, Ramita Dewan, Enrique Disla, Addison Goodley, Nathan

Lim, Lisa Liu, Lucas Place, Raeva Ramadorai, Jaishri Shankar, Michael Wellen, Diane Ye, Edward Yu

Research Problem Agricultural runoff, especially in the spring,

leads to high nitrate levels in the Chesapeake Bay Watershed

Causes harmful algal blooms◦ Result: Dead zones characterized by depletion of

oxygen and nutrients vital to aquatic wildlife Dead zone: low oxygen area of water

Research Problem – Significance of Project Affects fishing industry, seafood consumers,

environmental groups, residents of the Chesapeake Bay Watershed

Health of the Chesapeake Bay is vital for maintaining biodiversity

Purpose & Thesis & Hypothesis Purpose: To design a wetland that

optimally removes nitrates from the Chesapeake Bay and its surrounding waters

Thesis: We want to investigate what combination of native plant species and organic amendments best remove nitrates from the Chesapeake Bay

Hypothesis: We expect significant differences between the varying microcosms and empty controls

One of the largest sources of pollution into the Chesapeake Bay (Glibert et al., 2001)

Eutrophication causes harmful algal blooms Constructed wetlands

◦ Can remove up to 80% of inflowing nitrates (Crumpton & Baker, 1993)

Big Picture: Chesapeake Bay◦ Choptank River-largest eastern tributary in the

bay (Staver, L., Staver, K., & Stevenson, J., 1996)◦ Tuckahoe Creek-34% of Choptank, accessibility

(USDA Agricultural Research Service [ARS], 2009)

Literature Review – Agricultural Runoff and River Selection

Collection of Samples

Criteria for plant selection◦ Non-invasive◦ Native to the Chesapeake Bay

Watershed◦ Biofuel-capable

Cattail (Typha latifolia) (Fraser, Carty, & Steer, 2004; Matheson, 2010)

Soft-stem Bulrush (Schoenoplectus validus) (Rogers, Breen, & Chick, 1991)

Switchgrass (Panicum virgatum) (Larson, n.d.)

Literature Review – Plant Selection

Why biofuels?◦ To accommodate changing energy and environmental needs◦ Secondary data analysis

Cross-referenced list of Chesapeake Bay native, non-invasive plants with list of biofuel-capable plants (Fedler, Hammond, Chennupati & Ranjan, 2007; Wright & Turhollow, 2010; Zhang, Shahbazi, Wang, Diallo, & Whitmore, 2010)

Why organic amendments?◦ Increase differences in nitrate removal

Three carbon-based amendments◦ Glucose (Weisner, Eriksson, Graneli, & Leonardson, 1994)◦ Sawdust (Hien, 2010)◦ Wheat straw (Ines, Soares, & Abeliovich, 1998)

Literature Review – Biofuels & Organic Amendments

Phase 1◦ Goal: Find the most effective organic amendment ◦ Use only cattail

Phase 2◦ Goal: Find the most effective combination of

plants with the amendment◦ Use cattail, soft-stem bulrush, and switchgrass

Phase 3◦ Goal: Implement a large-scale design of the most

effective plant combination◦ Time and money permitting

Project Outline

1:1 mixture of topsoil and sand

Plastic tubes inserted into ½ holes

Tubes pinched with clothespins

Cattails planted six inches apart from one another

Problems encountered

Pilot Microcosm Design

Spigot system installed as shown

Two inches of gravel, covered by polyethylene fabric.

5 inches 1:1 topsoil/sand mixture

Plants: clumps of four Water depth: 5 inches Weighed microcosms ½ Liter of topsoil from

Tuckahoe for inoculation

New Microcosm Design

New Microcosm Design

8 week adjustment period

After adjustment period, add nitrates and organic amendments via a concentrated solution

Water samples from individual tubs

An Improved Procedure

We are using 8 groups:1. No plants, no

amendments2. No plants with Glucose3. No plants with Sawdust4. No plants with Straw5. Plants, no

amendments6. Plants with Glucose7. Plants with Sawdust8. Plants with Straw

Plant Groups

Preliminary Results Average Nitrate (NO3

-) concentration of Tuckahoe River Samples:◦ Spring: 2.67 mg/L◦ Fall: 2.65 mg/L

No significant difference between the concentrations across seasons, p > .05

Pilot Data

0 1 2 30

1

2

3

4

5

6

Nitrate Concentration vs. Week

Week

Nitr

ate

conc

netr

atio

n (m

g/L)

SAS 9.2 Trial Run: One Factor Repeated Measure

ANOVA No significant difference across weeks Nitrate removal significantly different from 0

(no change in nitrate concentration) Phase 1: Two Factor ANOVA with One Repeat

Measure Compare different microcosm environments

and week of trial

Data Analysis

Fall 2011◦ Carry out Phase 1 testing

Four 1 week trials◦ Collect sample data and analyze◦ Use results of Phase 1 in Phase 2 next semester

Spring 2012◦ Plant fresh microcosms and allow them to acclimate to

greenhouse◦ Carry out Phase 2 testing

Six 1 week trials◦ Collect sample data and analyze◦ Tie up loose ends◦ Begin compiling thesis

Future Directions

Summer/Fall 2012◦ Finish data collection and analysis, if necessary◦ Begin to implement Phase 3 of project, if time and

funds allow for it◦ Finish first draft of thesis◦ Contact discussants for thesis conference

Spring 2013◦ Edit thesis◦ Thesis conference!◦ Make final changes to thesis after conference◦ Citation ceremony and commencement!

Future Directions (cont)

Research◦ Everyone does everything

Writing/Literature◦ Subgroups◦ Group deadline: at least 2 weeks before hard

deadline Example: Junior Colloquium presentation was due

internally 3 weeks before we had to present it!

Team Composition

LOTS of unforeseen complications!

How did we account for these issues?◦ Build our schedules to

work around the project◦ Talk about it!◦ Revisit the project timeline

and make changes CONSTANTLY

Foreseeing Problems

Completed tasks: Thesis Proposal Pilot microcosm testing New microcosm design Phase 1 acclimation

To be completed: Phase 1 testing Phase 2 acclimation and testing Thesis Conferences

Conclusions

Put the work in early Find a good mentor! Form subgroups as needed Don’t be afraid to talk to your team! Use your librarian! Focus on the big picture…

For the Freshmen!

Dr. Dave Tilley Dr. James Wallace and the Gemstone Staff Ms. Betty Morgavan and the Greenhouse

Staff Mr. Robert Kackley Dr. Bruce James Mr. Brandon Winfrey Home Depot in College Park, MD

Acknowledgements

Anderson, D., & Glibert, P., & Burkholder J. (2002). Harmful algal blooms and eutrophication: Nutrient sources, composition, and consequences. Coastal and Estuarine Research Federation, 24(4), 704-726. 

Crumpton, W., & Baker, J. (1993). Integrating wetlands into agricultural drainage systems: Predictions of nitrate loading and loss in wetlands receiving agricultural subsurface drainage. In: Mitchell J (Ed). Constructed wetlands for water quality improvement. St. Joseph, MI: American Society of Agricultural Engineers. 118-26.

Fedler, C., Hammond, R., Chennupati, P., & Ranjan, R. (2007). Biomass energy potential from recycled wastewater. Lubbock: Texas Tech University.

Fraser, L. H., Carty, S. M., & Steer, D. (2004). A test of four plant species to reduce total nitrogen and total phosphorus from soil leachate in subsurface wetland microcosms. Bioresource Technology, 94(2), 185-192. 

Glibert, P., Magnien, R., Lomas, M., Alexander, J., Tan, C., Haramoto, E., et al. (2001). Harmful algal blooms in the Chesapeake and Coastal Bays of Maryland, USA: Comparison of 1997, 1998, and 1999 events. Estuaries and Coasts, 24(6), 875-883. doi: 10.2307/1353178

Hien, T. (2010). Influence of different substrates in wetland soils on denitrification. Water, Air, and Soil Pollution, June 2010, 1-12. doi:10.1007/s11270-010-0498-6

Ines, M., Soares, M., & Abeliovich, A. (1998). Wheat straw as substrate for water denitrification. Water Research. 32(12), 3790-3794. Karrh, R., Romano, W., Raves-Golden, R., Tango, P., Garrison, S., Michael, B., Karrh, L. (2007). Maryland tributary strategy Choptank

River basin summary report for 1985-2005 Data. Annapolis, MD: Maryland Department of Natural Resources. Larson, R.A. (n.d.) Nitrate uptake by terrestrial and aquatic plants. Unpublished manuscript, Office of Research Development and

Administration, University of Illinois at Urbana-Champaign, Carbondale, Illinois. Matheson, F. E., & Sukias, J. P. (2010). Nitrate removal processes in a constructed wetland treating drainage from dairy pasture.

Ecological Engineering, 36, 1260-1265. Rogers, K., Breen, P., & Chick, A. (1991). Nitrogen removal in experimental wetland treatment systems: Evidence for the role of aquatic

plants. Research Journal of the Water Pollution Control Federation, 63(7), 9. Staver, L. W., Staver, K. W., & Stevenson, J. C. (1996). Nutrient inputs to the Choptank river estuary: Implications for watershed

management. Estuaries, 19(2), 342-358. United States Department of Agriculture Agricultural Research Service (2009, June 16). Choptank River, Maryland: An ARS Benchmark

Research Watershed. Retrieved from http://www.ars.usda.gov/Research/docs.htm?docid=18632. Weisner, S., Eriksson, P., Granéli, W., & Leonardson, L. (1994). Influence of macrophytes on nitrate removal in wetlands. Ambio, 23(6),

363-366. Wright, L., & Turhollow, A. (2010). Switchgrass selection as a “model” bioenergy crop: A history of the process. Biomass and Bioenergy,

34(6), 851-868. doi:10.1016/j.biombioe.2010.01.030 Zedler, J. B. (2003). Wetlands at your service: reducing impacts of agriculture at the watershed scale. Frontiers in Ecology and the

Environment, 1(2), 65-72. Zhang, B., Shahbazi, A., Wang, L., Diallo, O., & Whitmore, A. (2010). Hot-water pretreatment of cattails for extraction of cellulose.

Journal of Industrial Microbiology & Biotechnology, 1-6. doi: 10.1007/s10295-010-0847-x

References

Completed tasks: Thesis Proposal Pilot microcosm testing New microcosm design Phase 1 acclimation

To be completed: Phase 1 testing Phase 2 acclimation and testing Thesis Conferences

Will discover optimum combination of plants to reduce nitrate levels running off into Chesapeake

Questions?

Conclusions