Dissolved Phosphate Concentration in Surface and Groundwater of EKU Meadowbrook Farm

arms are non-point sources for nutrient contaminants that drain into waterways and contribute to eutrophication and other environmental problems. EKU’s Meadowbrook Farm raises both crops and livestock, contributing dissolved phosphorus in the form of orthophosphate (PO43-) to surface and subsurface waters, eventually flowing into Muddy Creek, a tributary of the Kentucky River. We sampled springs, surface water from the farm, tile drains, and Muddy Creek waters from May through August 2016. One to two days after sampling, we measured orthophosphate concentration using the established colorimetric, ascorbic acid method and a UV-VIS spectrophotometer with general accuracy and precision of ~0.1 mg/L (ppm). Phosphate concentrations are generally low when compared to nitrate ranging from 0 to 0.1 mg/L P-PO4 with higher concentrations of 0.5 to 2.7 mg/L P-PO4 occurring sporadically. With some exceptions, we saw little difference in phosphate concentration between different sample sources whether spring water, water from subsurface drains, surface waters flowing over the Farm, or Muddy Creek waters. Overall patterns of phosphate concentration were similar whether sampling during periods with little or no rainfall, or periods following rain events. However, one sub-watershed draining the Farm had increased levels of phosphate on 24 May (up to 2.7 mg/L P-PO4), and on 24 June (0.5 mg/L P-PO4), immediately following a significant rain event. Overall, Farm and Muddy Creek waters had lower median dissolved orthophosphate (0.02 mg/L P-PO4) than runoff from agricultural areas nationally (0.15 mg/L P-PO4). Subsurface water from springs had a median level of phosphate (0.04 mg/L P-PO4) higher as compared to springs nationally

Nutrient contamination from non-point sources: Dissolved phosphate in surface and subsurface waters at EKU Meadowbrook Farm, Madison County, Kentucky

Farms are non-point sources for nutrient contaminants that drain into waterways and contribute to eutrophication and other environmental problems. EKU’s Meadowbrook Farm raises both crops and livestock, contributing dissolved phosphorus in the form of orthophosphate (PO43-) to surface and subsurface waters, eventually flowing into Muddy Creek, a tributary of the Kentucky River. We sampled springs, surface water from the farm, tile drains, and Muddy Creek waters from May through August 2016. One to two days after sampling, we measured orthophosphate concentration using the established colorimetric, ascorbic acid method and a UV-VIS spectrophotometer with general accuracy and precision of ~0.1 mg/L (ppm). Phosphate concentrations are generally low when compared to nitrate ranging from 0 to 0.1 mg/L P-PO4 with higher concentrations of 0.5 to 2.7 mg/L P-PO4 occurring sporadically. With some exceptions, we saw little difference in phosphate concentration between different sample sources whether spring water, water from subsurface drains, surface waters flowing over the Farm, or Muddy Creek waters. Overall patterns of phosphate concentration were similar whether sampling during periods with little or no rainfall, or periods following rain events. However, one sub-watershed draining the Farm had increased levels of phosphate on 24 May (up to 2.7 mg/L P-PO4), and on 24 June (0.5 mg/L P-PO4), immediately following a significant rain event. Overall, Farm and Muddy Creek waters had lower median dissolved orthophosphate (0.02 mg/L P-PO4) than runoff from agricultural areas nationally (0.15 mg/L P-PO4). Subsurface water from springs had a median level of phosphate (0.04 mg/L P-PO4) higher as compared to springs nationally (\u3c0.01 mg/L P-PO4)

Iron Transport by Subglacial Meltwater Indicated by δ56Fe in Coastal Sediments of King George Island, Antarctica

Iron (Fe) fluxes from reducing sediments and subglacial environments potentially contribute to bioavailable Fe in the Southern Ocean. Stable Fe isotopes (δ56Fe) may be used to trace Fe sources and reactions, but data are scarce and Fe cycling in natural environments is not understood sufficiently to constrain δ56Fe endmembers for different types of sediments, environments, and biogeochemical processes. δ56Fe data from pore waters and sequentially extracted solid Fe phases at two sites in Potter Cove (King George Island, Antarctica), a bay affected by fast glacier retreat, are presented. Close to the glacier front, sediments contain high amounts of easily reducible Fe oxides and show a dominance of ferruginous conditions compared to sediments close to the ice-free coast, where surficial oxic meltwater discharges and sulfate reduction dominates. We suggest that high amounts of reducible Fe oxides close to the glacier mainly derive from subglacial sources, where Fe liberation from comminuted material beneath the glacier is coupled to biogeochemical weathering. A strong argument for a subglacial source is the predominantly negative δ56Fe signature of reducible Fe oxides that remains constant throughout the ferruginous zone. In situ dissimilatory iron reduction (DIR) does not significantly alter the isotopic composition of the oxides. The composition of the easily reducible Fe fraction therefore suggests pre-depositional microbial cycling as it occurs in subglacial environments. Sediments influenced by oxic meltwater discharge show downcore trends towards positive δ56Fe signals in pore water and reactive Fe oxides, typical for in situ DIR as 54Fe becomes less available with increasing depth. Henkel et al. (2018) Diagenetic iron cycling and stable Fe isotope fractionation in Antarctic shelf sediments, King George Island. GCA 237, 320-338

Patterns and sources of anthropogenic contaminants in the Otter Creek Watershed, Madison County, Kentucky

Stream systems are often affected by anthropogenic activities that affect water quality and stream ecosystems. Land use typically determines the type and quantity of anthropogenic contaminants entering natural waters. The Otter Creek watershed (170 km2; Madison County, Kentucky) consists predominantly of pasture and rural housing, with some cropland. The basin also receives runoff from the town of Richmond and a sewage treatment plant operates within the watershed. We measured concentrations of nutrients (phosphate, ammonium, nitrate) and fecal microbes to discover levels of anthropogenic contaminants affecting water quality and to identify contaminant sources. We sampled 4 times in the summer field season of 2015 over a variety of conditions. Nutrients were measured colorimetrically using established colorimetric methods. The abundance of Escherichia coli was quantified using IDEXX rapid-assay techniques. Phosphate (0 – 0.5 mg/L) and ammonium (\u3c0.1 mg/L) concentrations were low for all sampling days, whereas nitrate was the dominant anthropogenic nutrient contaminant showing concentrations of 1 to 3 mg/L. Consistently higher levels of phosphate and nitrate were found in the waters of Dreaming Creek, which drains urban Richmond. High ammonium levels were sporadic and associated with pasture. High E. coli counts occurred in Dreaming Creek, the upper reaches of Otter Creek, and proximal to pastures. Both point- and non-point sources exist for contaminants. The sewage treatment plant is a definite point source for nitrate and less so for phosphate and ammonium. Non-point sources include high concentrations of nitrate, phosphate, and fecal microbes occur along Dreaming Creek, likely due to leaky sewage distribution pipes. Spikes in ammonium concentration are associated with cattle pasture, another non-point source. We also tested contaminant levels immediately before and after a rainfall event associated with tropical storm Bill (June 22). Phosphate and ammonium levels decreased, whereas nitrate increased significantly. E. coli counts also increased dramatically, after the rain event

Patterns and Sources of Anthropogenic Contaminants in the Otter Creek Watershed, Madison County, Kentucky By Elijah D. Wolfe Submitted to Walter S. Borowski Department of Geosciences Eastern Kentucky University Undergraduate Thesis May

Stream systems are often affected by anthropogenic activities that affect water quality and stream ecosystems. Land use typically determines the type and quantity of anthropogenic contaminants entering natural waters. The Otter Creek watershed (170 km2; Madison County, Kentucky) consists predominantly of pasture and rural housing, with some cropland. The basin also receives runoff from the town of Richmond and a sewage treatment plant operates within the watershed. We measured concentrations of nutrients (phosphate, ammonium, nitrate) and fecal microbes to discover levels of anthropogenic contaminants affecting water quality and to identify contaminant sources. We sampled 4 times in the summer field season of 2015 over a variety of conditions. Nutrients were measured colorimetrically using established colorimetric methods. The abundance of Escherichia coli was quantified using IDEXX rapid-assay techniques. Phosphate (0 – 0.5 mg/L) and ammonium ( Both point- and non-point sources exist for contaminants. The sewage treatment plant is a definite point source for nitrate and less so for phosphate and ammonium. Non-point sources include high concentrations of nitrate, phosphate, and fecal microbes occur along Dreaming Creek, likely due to leaky sewage distribution pipes. Spikes in ammonium concentration are associated with cattle pasture, another non-point source. We also tested contaminant levels immediately before and after a rainfall event associated with tropical storm Bill (June 22). Phosphate and ammonium levels decreased, whereas nitrate increased significantly. E. coli counts also increased dramatically, after the rain event

Grain-size properties of grab-sampled sediments from the German Bight during R/V Heincke cruise HE436

At 43 stations Van-Veen-Type grap samples (HELCOM standard) were collected to ground truth sidescan sonar backscatter data. Each sample was photographed and macroscopically described on board. Grain-size analyses for samples with fractions smaller than 2 mm were carried out with a CILAS 1180 L laser particle sizer (0.04-2500 µm) after chemical treatment according to standard procedures (Hass, H.C.; Kuhn, G.; Monien, P.; Brumsack, H.J.; Forwick, M. Climate fluctuations during the past two millennia as recorded in sediments from Maxwell Bay, South Shetland Islands,West Antarctica. Geol. Soc. Lond. Spec. Publ. 2010, 344, 243-260)

Grain-size properties of grab-sampled sediments from the German Bight during R/V Heincke cruise HE415 and HE416

At 78 stations Van-Veen-Type grap samples (HELCOM standard) were collected to ground truth sidescan sonar backscatter data. Each sample was photographed and macroscopically described on board. Grain-size analyses for samples with fractions smaller than 2 mm were carried out with a CILAS 1180 L laser particle sizer (0.04-2500 µm) after chemical treatment according to standard procedures (Hass, H.C.; Kuhn, G.; Monien, P.; Brumsack, H.J.; Forwick, M. Climate fluctuations during the past two millennia as recorded in sediments from Maxwell Bay, South Shetland Islands,West Antarctica. Geol. Soc. Lond. Spec. Publ. 2010, 344, 243-260)

Grain-size properties of grab-sampled sediments from the German Bight during R/V Heincke cruise HE505

At 26 stations Van-Veen-Type grap samples (HELCOM standard) were collected to ground truth sidescan sonar backscatter data. Each sample was photographed and macroscopically described on board. Grain-size analyses for samples with fractions smaller than 2 mm were carried out with a CILAS 1180 L laser particle sizer (0.04-2500 µm) after chemical treatment according to standard procedures (Hass, H.C.; Kuhn, G.; Monien, P.; Brumsack, H.J.; Forwick, M. Climate fluctuations during the past two millennia as recorded in sediments from Maxwell Bay, South Shetland Islands,West Antarctica. Geol. Soc. Lond. Spec. Publ. 2010, 344, 243-260). Samples with fractions larger than 2 mm were additionaly wet sieved

Grain-size properties of grab-sampled sediments from the German Bight during R/V Heincke cruise HE474

At 25 stations Van-Veen-Type grap samples (HELCOM standard) were collected to ground truth sidescan sonar backscatter data. Each sample was photographed and macroscopically described on board. Grain-size analyses for samples with fractions smaller than 2 mm were carried out with a CILAS 1180 L laser particle sizer (0.04–2500 µm) after chemical treatment according to standard procedures (Hass, H.C.; Kuhn, G.; Monien, P.; Brumsack, H.J.; Forwick, M. Climate fluctuations during the past two millennia as recorded in sediments from Maxwell Bay, South Shetland Islands,West Antarctica. Geol. Soc. Lond. Spec. Publ. 2010, 344, 243–260)

Grain-size properties of grab sampled sediments from the German Bight during R/V Heincke cruise HE400.

At 118 stations Van-Veen-Type grap samples (HELCOM standard) were collected to ground truth sidescan sonar backscatter data. Each sample was photographed and macroscopically described on board. Grain-size analyses for samples with fractions smaller than 2 mm were carried out with a CILAS 1180 L laser particle sizer (0.04-2500 µm) after chemical treatment according to standard procedures (Hass, H.C.; Kuhn, G.; Monien, P.; Brumsack, H.J.; Forwick, M. Climate fluctuations during the past two millennia as recorded in sediments from Maxwell Bay, South Shetland Islands,West Antarctica. Geol. Soc. Lond. Spec. Publ. 2010, 344, 243-260). Samples with fractions larger than 2 mm were additionaly wet sieved