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2004
Research Program Water Quality and Nutrient Cycling in Indianapolis' Drinking Water Reservoirs and Their Watersheds The 2004 Water Quality and Nutrient Cycling research follows the 2003 comprehensive monitoring study, Water Quality and Nutrient Cycling in Three Central Indiana Watersheds and Their Reservoirs: Eagle Creek/Eagle Creek Reservoir, Fall Creek/Geist Reservoir, and Cicero Creek/Morse Reservoir. The project will be implemented in March of 2004 and consists of five components: (1) Hypolimnetic Anoxia Study; (2) Phytoplankton Community Structure Study; (3) Nutrient Mass Balance Study; (4) Effects of Watershed Residential Development on Stream Loading and Water Quality Study; and (5) Watershed Input Tracking of Organic Matter and Nutrients Study. In addition to these five studies, the program will continue to monitor copper loading to reservoir sediments. One long-range goal of the research objectives of CIWRP is to characterize, model, and predict the major impacts on water resource quality in central Indiana. The first phase of our efforts have focused on bulk characterization of the geochemistry, microbiology, and sedimentology of the three principle reservoirs (with emphasis on Eagle Creek Reservoir), on the characterization of watershed loading and the hydrologic and sediment dynamics of watershed inputs to those reservoirs, and on the modeling of land-use and land-use change to develop a framework for targeted watershed-scale analysis of important factors (e.g., nutrients, carbon, sediment) that may have future impacts on water quality in central Indiana. This first phase has allowed us to develop a research infrastructure that will propel us toward significantly more advanced and quantified studies of water quality factors in this region. It has also produced several key findings:
(1)
The sediments in the reservoir bottoms
are highly enriched in phosphorus and organic carbon, a
condition that might contribute to eutrophication and
water quality degradation These findings lead us to a refined set of questions that we will begin addressing with this year’s research efforts:
(1)
What role does the benthic reflux of
phosphorus from reservoir bottoms play on
ecosystem dynamics and water quality? Does carbon and
nitrogen cycling within the reservoir also contribute?
Is this flux a trigger for algal blooms? We have designed this year’s research projects to address these questions, and to continue with efforts to monitor the watersheds as defined under the general research plan of CIWRP. Following are the work plans split into five components studies. These studies are not independent of each other, however, and will depend on complementary sampling and analytical protocols to enhance their net impact. These studies will involve researchers in CEES and Earth Sciences at IUPUI, the research staff at Veolia Water Indianapolis laboratories, and a Tim Filley, a biogeochemist at Purdue University (noted in the last section as a sub-contract).The work plan for the subcontracted work is presented in more detail as the techniques are new to the research program. The work plans provide a framework for project approval with some of the sampling schedules and methods still being finalized with input from Veolia Water Indianapolis labs and additional coordination between Filley and CEES/IUPUI sampling programs. PROJECT COMPONENTS (1) Spatial and Temporal Hypolimnetic Anoxia in Eagle Creek Reservoir Objectives:
Profile data and discrete at-depth water samples will be taken at 14 stations in Eagle Creek Reservoir. Discrete water samples will be analyzed for Alkalinity, Hardness, Carbon (TOC, DOC, and DIC), Nitrogen (TKN, Total Nitrogen, nitrate, and ammonia), Phosphorus (Total P and Ortho-P), Silica (Total Si), Anions (Chloride and Sulfate) and Cations (Calcium, Potassium, Magnesium, Sodium, Manganese and Iron). Water column profiles at each station will include at-depth measurement of DO, pH, Temperature, Specific Conductance, Salinity, and TDS. Samples will be taken three times: once before the reservoir becomes thermally stratified, once during stratification, and once after the reservoir becomes re-mixed after stratification. Two, three, or four depths will be sampled at each station depending on water column stratification and station depth. The study will generate approximately 148 water samples. Samples will be analyzed by both CEES researchers and Veolia Water Indianapolis Labs as follows:
Veolia
Water Indianapolis Labs:
IUPUI
Labs: (2) Phytoplankton Community Structure and Distribution in Eagle Creek Reservoir Objective:
Pooled water samples will be taken over twice the Secchi Disk depth at 14 stations in Eagle Creek Reservoir during three seasonally significant times of the year: spring-early summer, late summer, and fall. Pooled samples will be analyzed for phytoplankton identification and enumeration, chlorophyll a, and MIB and Geosmin concentrations. Sample collection will result in the generation of ~48 samples including replicates. The study will be done in tandem with the Hypolimnetic Anoxia study. Samples will be analyzed by both CEES researchers and Veolia Water Indianapolis Labs as follows:
Veolia
Water Indianapolis Labs:
IUPUI
Labs: (3) Eagle Creek Reservoir: Mass Balance a. Watershed Nutrient Loading Objectives:
Discrete water samples, suspended sediment samples, in-situ physical and chemical measurements, and discharge data will be taken at four watershed sites in Eagle Creek Watershed. These include one station at each of the major tributaries into Eagle Creek Reservoir: Fishback Creek, School Branch Creek, and Eagle Creek, one station at the T.W. Moses Raw Water Intake Structure, and one station downstream of the Eagle Creek Dam. Sampling will occur on a bi-weekly basis from March 2004 – October 2004. Discrete water samples will be analyzed for Alkalinity, Hardness, Carbon (TOC, DOC, and DIC), Nitrogen (TKN, Total Nitrogen, nitrate, and ammonia), Phosphorus (Total P and Ortho-P), Silica (Total Si), Anions (Chloride and Sulfate) and Cations (Calcium, Potassium, Magnesium, Sodium, Manganese and Iron). In-situ profiles at each station will include at-depth measurement of DO, pH, Temperature, Specific Conductance, Salinity, and TDS. Suspended sediment samples will be analyzed for exchangeable phosphorus. This study will result in the generation of 85 discrete water samples and 85 suspended sediment samples. Samples will be analyzed by both CEES researchers and Veolia Water Indianapolis Labs as follows:
Veolia
Water Indianapolis Labs:
IUPUI
Labs: b. Reservoir Nutrient Dynamics Objectives:
Discrete water samples, in-situ physical and chemical measurements, and pooled water samples over twice the Secchi Disk depth will be taken at four reservoir stations in Eagle Creek Reservoir. Two stations will be located in the northern basin and two in the southern basin. Sampling will occur on the same schedule and on the same days as the Watershed Nutrient Loading study, that is, on a bi-weekly basis from March 2004 – October 2004. Discrete water samples will be analyzed for Alkalinity, Hardness, Carbon (TOC, DOC, and DIC), Nitrogen (TKN, Total Nitrogen, nitrate, and ammonia), Phosphorus (Total P and Ortho-P), Silica (Total Si), Anions (Chloride and Sulfate) and Cations (Calcium, Potassium, Magnesium, and Sodium). In-situ profiles at each station will include at-depth measurement of DO, pH, Temperature, Specific Conductance, Salinity, and TDS. Pooled samples will be analyzed for phytoplankton identification and enumeration, chlorophyll a, and MIB and Geosmin concentrations. This study will result in the generation of ~192 discrete water samples and ~80 pooled samples. In an effort to provide supporting data to the evaluation of algaecide treatment strategies, we have been considering how this study might be modified to provide relevant data. One approach could be to utilize discrete depth, rather than, pooled samples for phytoplankton identification and enumeration. This would significantly increase the number of samples generated by this study and would likely not be helpful. Since the location of algae is depended upon so many variables (light intensity, turbulence, temperature, predation, etc) detailed work determining the depth distribution of the algae is only relevant for the time and place the sample was taken. At this time, we are not sure how we could construct an experiment or monitoring system to track cutrine effectiveness other than using chlorophyll probes and measuring where the chlorophyll peak is just before cutrine application. This is somewhat impractical because of the time this would take relative to application preparation and application. Samples will be analyzed by both CEES researchers and Veolia Water Indianapolis Labs as follows:
Veolia
Water Indianapolis Labs:
IUPUI
Labs: (4) Effects of Watershed Residential Development on Stream Loading and Water Quality Objectives:
Stream water samples will be collected in spring, summer, and fall/winter, during base flow and event flow conditions in two subwatersheds with no more than eight stations per watershed. Discharge will be gaged at important watershed points to allow for sample calibration relative to flow. Events will be sampled at up to three different times during the evolution of the event flow. Event flow samples will be analyzed for dissolved components including alkalinity, hardness, turbidity, DOC, TOC, DIC, nitrite, nitrate, TKN, ammonia, total nitrogen, total soluble phosphorus, soluble reactive phosphorus, soluble silica and total silica, Anions (chloride, sulfate), Cations (calcium, magnesium, potassium, and sodium). Suspended sediments will also be sampled and analyzed for total phosphorus, exchangeable phosphorus, total carbon, total hydrogen, and total nitrogen, and carbon as loss on ignition. Base flows will be sampled twice over the base flow period and will only be analyzed for dissolved components. In-situ water parameters (salinity, pH, temperature, DO, specific conductance, and TDS) will be measured at each sampling location. Sample counts are complex but can be estimated as follows: total for event samples is approximately 144 samples (3 seasons, 2 watersheds, 3 times during event, 8 stations); total for base flow samples is approximately 96 samples (3 seasons, 2 watersheds, 2 sampling event per base flow period, 8 stations). Samples will be analyzed by both CEES researchers and Veolia Water Indianapolis Labs as follows:
Veolia
Water Indianapolis Labs:
IUPUI
Labs: (5) Watershed Input Tracking of Allochthonous Organic Matter and Nutrients to Eagle Creek, Geist, and Morse Reservoirs Objectives:
This portion of the project will be performed through subcontract to Timothy Filley, Department of Earth and Atmospheric Sciences, Purdue University. This portion of the research program is presented in considerably more detail than the other research components as they represent new approaches, tools and facilities than have previously been presented. Purpose To effectively pursue the mass balance approach to predictive water quality modeling of Eagle Creek Reservoir (ER), Geist Reservoir (GR), and Morse Reservoir (MR) it is imperative that the spectrum of physical forms (dissolved, colloidal, particulate) that nutrients and associated organic matter fractions may take in streams be characterized, monitored, and assessed. Such a characterization is particularly important as preliminary studies have demonstrated that a significant proportion of nutrients to ER and GR are externally loaded. Although there is strong evidence that the high carbon contents of the reservoir sediments are due to algal productivity we believe that pulsed hydrologic events (storms and snow melt) may simultaneously transport, in a punctuated fashion, significant amounts of metabolizable organic matter and nutrients. Such inputs may be very important for driving heterotrophic activity and play an important control on internal biogeochemical cycling patterns as well as external triggering of algal blooms. For this reason a detailed, high resolution monitoring program of watershed input is proposed. Watershed Input Tracking An important factor that will determine the impact of allochthonous organic matter (AOM) and nutrients is its metabolizabilty. Organic matter metabolizability will be a function of chemical form, molecular weight range, structural form, and its association with clays and mineral phases (Ammon and Benner, 2000; Kalbitz et al., 2003). Therefore, to effectively manage the hydrologic resources of ECR, GR, MR and respond to nuisance algal blooms one must be able to predict both the quantity and reactivity (quality) of AOM and associated nutrients. To accomplish this task a high resolution temporal sampling of the chemical composition, size, molecular chemistry, and stable isotope composition of AOM entering the reservoirs from the watersheds is required. Additionally, these watershed parameters must be related to resultant responses of the reservoir algal community and reservoir water column chemistry. Specifically, we will use ultrafiltration technology (Guo et al., 2000) and molecular isolation techniques such as alkaline CuO oxidation (Hedges and Parker, 1976) to discern between different plant sources and the dynamic response of plant and soil organic matter during transport to the reservoir. The molecular techniques will focus upon the structure of the organic matter to discern among taxonomic groups such as C4 (e.g. corn) and C3 (e.g. soy) and plant tissue types (leaves, roots, woody tissue). Differences in photosynthetic mechanisms (O’leary, 1988) among the various crops and natural plant communities will make it possible to use stable carbon isotope analysis of colloidal and DOM fractions to help discriminate between sources of organic matter (e.g. Dienes, 1980; Onstad et al. 2000; Filley et al., 2001). Such an approach will be most useful when effluents in ditches and streams are receiving leachates and overland flow from both corn/grasses (δ13C ~ -12 to -14 ‰) and soy (δ13C ~ -23 to -27 ‰) crops. We will also couple molecular isolation techniques to stable carbon isotope analysis (Goni and Eglinton, 1996; Filley et al., 2001; Bianchi et al 2004) to discern between different sources of lignin and cuticle biopolymer sources allowing a detailed assessment of the changing pools of vascular plant input as a function of hydrology, season, and land use. Historical Trends in Watershed Input of AOM and Internal Algal Productivity The high carbon concentration and suboxic nature of some deeper areas in the reservoirs suggests that there may be slower organic decomposition and an enhanced preservation of chemical signatures that would allow for a detailed biogeochemical reconstruction of organic matter input. Because vascular plants and algae produce distinct types of biological compounds we will be able to use detailed biomarker and isotope approach to reconstruct the nature and relative timing of AOM input events and blooms. Algal biomarkers, unlike the macromolecular lignin and cuticle-derived fragments from vascular plants, are generally lipid molecules whose chemical structure can be very indicative of a class of algal organism. To track algal sources among, for example, diatoms and cyanobacteria, we might utilize lipid molecules such as brassicasterol or pentacosanoid highly branched isoprenoids as proxies for diatoms while mid chain methyl n-heptadecane could be used to track input of cyanobacteria (e.g. Ficken et al., 1998, 2000; Filley et al., 2001). The advantage of the biomarker approach is that lipids are relatively stable with respect to the proteins and carbohydrates which make up most of the cell so they are preserved in sediments. This algal biomarker analysis activity will be coordinated with other tasks investigating the detailed sedimentary mineralogy, bulk elemental composition and concentration, and phosphorus speciation that is proposed elsewhere in this research program. It will be important to coordinate these sedimentary lipid studies with water column sampling of algal species as we will need to determine the lipid structural distribution of the algae to develop effective proxies for the organisms in the sedimentary record. Methods Filtration/Ultrafiltration of the Stream and Reservoir Water: Detailed chemical characterization of the organic carbon in the water samples will be made using the following protocol outlined in Figure 1. Water will be collected in the field using peristaltic pumps in acid-washed silicon-based tubing into 20 liter acid-washed carboys or recovered from acid washed ISCO bottles. Samples will be filtered to 0.7 μm (or 0.45 μm ) in the field using glass fiber filters. Dissolved and colloidal organic matter (DOM) will be isolated from the GF/F filtrate and fractionated into molecular weight ranges using hollow fiber ultrafiltration (Guo et al. 2000). The filtrate will then be separated into a colloidal fraction at >0.2 μm. The dissolved organic matter fraction will be concentrated and defined as either a high molecular weight DOM fraction >1KDa (using an ultrafilter) and a low molecular weight DOM fraction at <1KDa. Characterization of Filtered Fractions: The amount of carbon in each filtered and ultrafiltered fraction will be defined by catalytic decomposition in a DOC analyzer (Shimadzu Model TOC-V). The level of particulate organic carbon (POC) will be defined as the organic carbon retained on a cleaned (by combustion at 475°C for 8 hours) glass filter. The fraction of organic carbon and its stable carbon isotope composition in the POC will be determined by
Figure 1. Isolation and analysis scheme used for dissolved and colloidal organic matter from stream, reservoir and tile water. inline combustion on a CHN elemental analyzer interfaced to a PDZ Europa stable isotope mass spectrometer. In this way elemental analysis and stable carbon and nitrogen isotope composition will be determined simultaneously. We will use molecular chemolytic techniques (Goni and Hedges, 1990; Filley et al. 2000; Filley et al. 2001) combined with gas chromatography/structural mass spectrometry to determine the abundance and structure of plant biopolymer (primary lignin, cutin, and suberin) components as well as extractable lipid components. Additionally, compound-specific stable-carbon isotope analysis (CSIA) will be used to discriminate between C3 (~-25‰) and C4 (~-13‰) lignin and wax components of the DOM (Goni and Eglinton, 1996, Filley et al. 2001). Biomarker Characterization of Sediments: Frozen sections of the core will be weighed and transferred into cellulose thimbles for Sohxlet extraction with a 2:1 v/v mixture of methylene chloride and methanol for 24 h to isolate the total lipid extract (TLE). A neutral lipid fraction will be obtained after base saponification of the TLE. The neutral lipids will be separated into compound classes (e.g. hydrocarbons, alcohols) by column chromatography using silica gel deactivated with 5% (by weight) water according to procedures modified from Wakeham and Volkman (1991). Quantification of lipid components will be performed by gas chromatography, using either a Shimadzu QP5050A quadrupole GC/MS or an HP 5890 gas chromatograph, containing a 5% phenyl polymethylsiloxane, capillary column (30 m, 0.25 mm i.d. HP-5) interfaced to an HP 5971 quadrupole mass spectrometer. Alcohols will be converted to trimethylsiloxyl derivatives with a 1:1 solution of bis (trimethylsilyl) trifluoroacetamide (BSTFA) and acetonitrile heated at 65 _C for 2 h prior to GC analysis. The carbon-isotope composition of individual lipids will be determined by isotope-ratio-monitoring gas chromatography–mass spectrometry (irmGC–MS) according to the procedures outlined in Merritt and Hayes (1994) and Merritt et al. (1995) using a Shimadzu GC17A gas chromatograph interfaced to a PDZ-Europa isotope-ratio-monitoring mass spectrometer via a micro-combustion furnace. Facilities and Equipment for Filley-Purdue Subcontract Two biogeochemistry laboratories are maintained by Dr. Filley, his students, and a part time wet chemistry technician. These laboratories contain three fume hoods and are well supplied with equipment for laboratory work analysis outlined herein. The following items are maintained by T. Filley and located within his laboratory. 1. A PDZ Europa 20/20 stable isotope ratio mass spectrometer with continuous flow interface. GC (Shimadzu GC17A) and elemental analyzer inlets are interfaced to the CF interface to provide compound-specific (C,N) and elemental (C,N) isotope analysis. 2. A Shimadzu GC17A gas chromatograph with autosampler interfaced to a QP5050A quadrupole mass spectrometer. 3. An Hewlett Packard 5971 quadrupole MS interfaced to a 5890 series 2 GC with auto sampler. 4. Pyr4a Shimadzu pyrolyzer interfaced to item 2 above for pyrolysis or thermochemolysis mass spectrometry of macromolecules. 5. A Shimadzu GC17A gas chromatograph with autosampler equipped with a flame ionization detector and a sulfur selective flame photometric detector. 6. A capillary preparative fraction collector consisting of a Hewlett Packard 6890 gas chromatograph with large volume injection port and autosampler interfaced to a Gerstel Inc. 7-chamber fraction collector. The GC is also equipped with a computer-controlled cryofocus to permit two-dimensional chromatography. 7. Prime Focus alkaline copper oxide oxidation bombs for 12 simultaneous analyses of lignin in natural samples. The following items are maintained by T. Filley and located within his laboratory. Filley also has shared ownership within a common instrument facility of a Finnigan Polaris Q LC/MS and Polaris Q GC/MS as well as access to UV spectrometers in the same facility. References Wakeham, S.G., Volkman, J.K., 1991. Sampling and analysis of lipids in marine particulate matter. In: Marine Particles: Analysis and Characterization. American Geophysical Union, Geophysical Monograph 63, pp. 171–179. O’Leary, M.H., 1988. Carbon isotopes in photosynthesis. Bioscience 3, 328–336. Deines, P., 1980. The isotopic composition of reduced organic carbon. In: Fritz, P., Fontes, J.C. (Eds.), Handbook of Environmental Isotope Geochemistry: The Terrestrial Environment. Elsevier Scientific, Amsterdam, pp. 329–406. Amon, R.M.W., and Benner, R. 1996. Bacterial utilization of different size classes of dissolved organic matter. Limnology and Oceanography 41, 41-51. Bianchi T. S., Filley. T.R., Dria K. and Hatcher P.G. 2004-March. Temporal Variability in Sources of Dissolved Organic Carbon in the Lower Mississippi River Geochimica et Cosmochimica Acta. Ficken, K.J., Barber, K.E., Eglinton, G., 1998. Lipid biomarker, _13C and plant macrofossil stratigraphy of a Scottish montane peat bog over the last two millennia. Organic Geochemistry 28, 217–237. Ficken, K.J., Li, B., Swain, D.L., Eglinton, G., 2000. An n-alkane proxy for the sedimentary input of submerged/floating freshwater aquatic macrophytes. Organic Geochemistry 31, 745–749. Goñi, M.A., Eglinton, T.I., 1996. Stable carbon isotopic analyses of lignin-derived CuO oxidation products by isotope ratio monitoring-gas chromatography-mass spectrometry (irm-GC–MS). Organic Geochemistry 24, 601–615. Hedges, J.I., Parker, P.L., 1976. Land-derived organic matter in surface sediments from the Gulf of Mexico. Geochimica et Cosmochimica Acta 40, 1019–1029 Merrit, D.A., Hayes, J.M., 1994. Factors controlling precision and accuracy in isotope-ratio-monitoring mass spectrometry. Analytical Chemistry 66, 2336–2347. Merritt, D.A., Hayes, J., DesMarais, D.J., 1995. Carbon isotopic analysis of atmospheric methane by isotope-ratio-monitoring gas chromatography-mass spectrometry. Journal of Geophysical Research, Section D, Atmospheres 100, 1317–1326. (6) Reservoir Bottom Sediment: Metal Loading Monitoring In order to monitor the potential for continued metal loading in bottom sediments of reservoirs, surface sediment grab samples will be collected from Eagle Creek, Geist and Morse Reservoirs. Samples will be analyzed for grain size, organic matter content, and metal content. 15 samples will be collected from each reservoir with site location based on previous sediment concentration maps and cutrine application zones. Results will be compiled into distribution maps for the measured parameters.
Samples will be analyzed
entirely at IUPUI/CEES researchers. |
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Center for Earth and Environmental
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