Analysis of Attert River Basin Surface and Sub-surface Soil Using a Fingerprinting Technique

1. Analysis of Attert River Basin Surface and Sub-surface Soil Using a Fingerprinting Technique Sebastian Ellra Andrews Centre de Recherche Public, Cellule de Recherche en Environnement et Biotechnologies (CREBS) facility in Luxembourg, LUX. Carlson School of Chemistry and Biochemistry Clark University, Worcester, MA 01610 2004

2. Overview

3. The Attert River Basin

4. The case for the Attert River basin • Most substances such as phosphorus throughout the basin are transported during storm events that generate overland flow. • Soil samples to be collected from representative locations throughout the basin; fluvial samples extracted from river water during storm events. • Goal of better understanding the export of substances into the Attert

5. Collection of Samples

6. Surface soil and soil profile sample locations

7. Land use of Surface Soil samples • 39 surface soil samples, 18: pasture land, 8: cultivated wheat fields, 5: cultivated corn fields, and 8: forestland. • Agricultural and farmland samples emphasized due to low elevation and abundance.

8. Bank sample locations

9. Methods of analysis Kjeldahl reagent: 135 g K2SO4, 200 mL H2SO4 (97%), and 800 mL of H20.

10. Method of analysis: aluminum and total phosphorus Reagent for phosphorus analysis Eriochrome cyanine R 300 mg of Eriochrome dye dissolved in 50 mL of H20 and pH adjusted to ~2.9 with 1:1 acetic acid, diluted to 100 mL with H20. • dilution of 63 mL concentrated H2SO4 with 500 mL water. • 0.2743 g K(SbO)C4H4O6-0.5H2O dissolved in 200 mL water and filled to 250 mL. • 10 g (NH4)6Mo7O24-4H2O dissolved in 250 mL water. • 1.76 g of ascorbic acid in 100 mL water.

11. Methods of analysis:iron and humic acids Analysis of sodium, magnesium, total nitrogen, potassium (K2O), and organic substrate were carried out by the ASTA Administration des services techniques de l’Agriculture in Ettelbruck, Luxembourg. Phenanthroline a time-dependant orange-red solution of a three aromatic ring system that chelates Fe2+.

12. Aluminum in bank and surface soil samples • Mean concentrations of aluminum for surface soil samples, Attert bank samples, and tributary bank samples were 29.9 mg/g, 30.3 mg/g, and 26.9 mg/g of soil respectively. • Samples BT(7-9) and BA4 are likely to be primary sources of aluminum for deposition into the Attert River. • Surface samples 25-27 and BT(7-9) are in close geographic proximity.

13. Aluminum in soil profiles • Aluminum concentrations in the forest soil profile were significantly lower than those extracted from pasture and cultivated lands. • Aluminum concentrations of bank and surface samples may originate from pasture and cultivated lands moreso than forest.

14. Total Phosphorus in bank and surface soil samples • Mean concentrations of total phosphorus for surface soil samples, Attert bank samples, and tributary bank samples were 0.70 mg/g, 0.40 mg/g, and 0.48 mg/g of soil respectively. • Tributary bank samples BT4 and BT8 may have larger influence on the amount of phosphorus present in the Attert River. • Some of the aluminum present in the BT8 tributary may be ionically bound to phosphorus in the form of phosphate ions.

15. Total Phosphorus in soil profiles • Phosphorus concentrations remain constant in cultivated and forest profiles, whereas pasture phosphorus level drop dramatically with increasing depth. • The decay of animal waste at soil surface and/or the presence of non-soil substances such as clay far below the surface.

16. Iron in bank and surface soil samples • Mean concentrations of iron for surface soil samples, Attert bank samples, and tributary bank samples were 22.2 mg/g, 21.6 mg/g, and 21.0 mg/g of soil respectively. • Similar to aluminum concentrations, surface soil samples 25-29 and BT(7-9) are in close geographic proximity, indicating an area of the basin containing higher level of iron than the rest. • Surface soil samples SS3, 9 have very low concentrations of not only iron, but aluminum and phosphorus.

17. Iron in soil profiles • Very similar pattern to aluminum levels in each profile, although at lower concentrations. • Cultivated and pasture lands appear to contribute more to levels of iron in the Attert River basin.

18. Magnesium, sodium, and potassium (K2O) in bank and surface soil samples • Concentrations of sodium and magnesium are consistent between all bank and surface soil samples. • Potassium concentrations of several surface samples are significantly greater than others.

19. Magnesium and potassium (K2O) in two soil profiles • Tilling of soil may explain consistency of potassium concentrations in cultivated profile; may be added in the form of a fertilizer. • Magnesium and potassium used in many biological aspects of plants such as photosynthesis, pigments, and disease resistance. • Potassium concentrations in pasture profile are very similar to that of total phosphorus.

20. Nitrogen and organic substrate for bank and surface soil samples (% by mass) • Very similar trend between nitrogen and organic substrate percentages in both sample types. • BT8 has much larger concentrations than other bank samples; BT8 also had highest aluminum and total phosphorus concentrations.

21. Nitrogen and organic substrate for soil profiles (% by mass) • Highest concentrations of nitrogen and organic substrate found at 10-15 cm fractions. • Presence of root systems and decaying foliage may explain higher organic substrate concentrations at shallower fractions. • Crop tilling may also be a factor in cultivated profile

22. Humic acid analysis for bank and surface soil samples (relative QSUs) • Surface soil samples with highest humic acid content were extracted from primarily forest land. • Most samples that have high humic acid content are also rich in organic substrate. • Due to high concentrations of humic acids and aluminum, the possibility of a ternary complex involving ion ‘bridging’ behavior with pesticide/herbicide agent is significant. • Sample BT3 appears to have very high humic acid concentrations but low overall organic substrate content.

23. Humic acid analysis for soil profiles (relative QSUs) • Pasture and forest profiles show negative trend in relative humic acid concentrations with increasing fraction depth. • Tilling may be responsible for consistent humic acid levels in the cultivated profile.

24. Conclusions • Bank sample BT8 seems to be a key depositor of several substances such as aluminum, phosphorus, and nitrogen into the Attert River. • In general, forested surface soil samples of the Attert River basin appear to be minor contributors to deposition of metals such as aluminum, iron, magnesium, and potassium. • Farmland soil tilling clearly has an affect of the presence of many substances at the soil surface. • Root systems and decaying organic matter such as leaves influence levels of humic acids, and organic substrate. • More solid conclusions as to the effect of substance concentrations in soil on deposition into the Attert during flooding events can be made with comparisons to fluvial analyses of the river water itself (ongoing).

25. Acknowledgements • Dr. Donald J. Nelson; professor, advisor, and sponsor. • Uwe Gertz; Director of Study Abroad Office. • Centre de Recherche Public, Cellule de Recherche en Environnement et Biotechnologies (CREBS) facility in Luxembourg, LUX. • ASTA Administration des services techniques de l’Agriculture in Ettelbrück, LUX.