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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Stormwater runoff effects on nutrient loads in the upper White River of Muncie, IN

Todd, Kristi M. 20 July 2013 (has links)
This study investigated temporal changes in nutrient concentrations and other water quality parameters at one sampling location at Muncie, Indiana in the Upper White River Watershed. Baseline sampling was conducted weekly over a six-month period in 2012 and focused on the analysis of total suspended solids and different forms of nitrogen and phosphorus. Three storm events were also investigated to understand how storm water runoff affected nutrient concentrations and other water quality parameters. It was hypothesized that storm events would temporarily increase nutrient concentrations in the river. Overall, nutrient concentrations increased during the initial stages of storm events and subsequently decreased at a rate slower than discharge. Concentrations measured exceeded recommended limits suggesting that these contaminants could cause eutrophication at downstream locations. These data suggest that improved or increased best management practices should be implemented in the Upper White River Watershed to control the inputs of nutrients into the river. / Department of Natural Resources and Environmental Management
12

Assessment of Escherichia coli in three subwatersheds of the upper White River, IN

Barnard, Amity R. January 2004 (has links)
According to the U.S. Environmental Protection Agency, 174 of Indiana's 428 waterbodies were listed as impaired for Escherichia coli (E. coli) in 2002. This study determined the severity of E. coli contamination and assessed the impacts of landuse on E. coli concentrations in three subwatersheds. Samples were collected and E. coli analyzed using the Coliscan Easygel method. Geographic information system analyses were used to determine impacts of spatial parameters on E. coli concentrations. Sixty-seven percent of the 162 samples exceeded the USEPA recreational water quality standard. Escherichia coli concentrations were significantly related to the ratio of five-and thirty-meter impervious surface buffer, density of septic systems, and the presence of inadequately drained soils. Confined feeding operations and combined sewer overflows also resulted in elevated E. coli concentrations. Human activity in urban areas had substantial impacts on these concentrations, impacts that can be minimized through proper management. / Department of Natural Resources and Environmental Management
13

The effects of storm events on the behavior of hydropsychid net-spinning caddisflies

Sobat, Thomas A. January 2007 (has links)
Physical disturbance in the form of storm events has been implicated as a major determinant of community structure in streams. But there has been limited study of this effect on individual taxa within the communities. Such work is needed because of untested assumptions regarding the behavior of bioindicator species in these systems. Development of intricate indices of insect tolerances to organic pollution have become commonplace in environmental monitoring. However, research on the effects of natural disturbance on biological water quality assessment is lacking. Hydropsychid caddisflies are relatively intolerant to organic pollution and the United States Environmental Protection Agency has outlined the use of these organisms and others as an indication of clean water. If a species is recorded as absent from samples when it is present but hidden, this false negative would bias the water quality assessment. I tested hypotheses regarding the behavior of hydropsychid caddisflies facing increased discharge, and the effect of stream size on the magnitude of this phenomenon.Three sites along the West Fork of the White River, Indiana USA were studied during nine storms between 2001 and 2004. Stratified sampling from the upper 15 cm of substrate prior to and just after a storm, and again following reestablishment of normal flow, revealed alterations of hydropsychid distributions. During storms all but one species sought refuge in the hyporheic zone at depths dependent upon storm intensity. The possibility that poor water quality resulting from increased discharge caused the hydropsychid behavior was refuted by chemical analysis. Family level biotic index (FBI) data demonstrated that increased discharge results in a reduction of stream FBI values. These results indicate that high intensity storm events influence biological monitoring and should be factored into sampling protocol. / Department of Biology
14

The influence of copper, lead and iron on stream sediment nitrification

Reising, Nicholas C. 04 May 2013 (has links)
Metals are naturally found in ecosystems but can also enter via human activity such as fossil fuel combustion, and disposal of metal products. Copper, lead, and iron have frequently been detected throughout Indiana freshwaters based on historical samples. Since microbial activity is a holistic measure of ecosystem function, changes in microbial activity in response to metals may indicate potential areas of concern. Metal concentrations in seven streams of the Upper White River watershed of central Indiana were measured during spring (May) and summer (August) in conjunction with measurement of sediment nitrification rates using the nitrapyrin-inhibition technique. Additionally, the influence of copper, lead, and iron on microbial nitrification was studied using in vitro mesocosms inoculated with stream sediment from selected sites. Copper, lead, and iron concentrations in stream sediment and water varied among sites with sediment concentrations ranging 654 – 1985 mg Fe/kg sediment and 1.00 - 2.91 mg Cu/kg sediment. Water concentrations ranged from below detection to 0.10 mg Fe /L, and 0.01 – 0.02 mg Cu/L. Lead concentrations were below detection at all sites except in May at one site (Pleasant Run Creek 0.47 mg Pb/kg sediment) and in August at one site (Mud Creek 0.38 mg Pb/ kg sediment). Stream sediment nitrification rates were positively correlated to stream sediment copper concentration (r = 0.78, p = 0.001). There was no significant correlation between sediment nitrification rates and stream sediment iron, pH, dissolved iron, or total dissolved solids (TDS; p > 0.05). Positive correlations were found between nitrification response rates and total Fe (r = 0.61, p = 0.02) and Cu (r = 0.74, p = 0.002) concentrations. Experimental mesocosms indicate metal addition of 127 mg/L may reduce stream sediment nitrification rates though stream physiochemical characteristics and history of metal exposure likely dictate microbial response. Further, metal concentrations in the stream sediment may have more of an influence on nitrifying microbes than dissolved metal in the water column. / Department of Biology
15

Nitrous oxide emission from riparian buffers in agricultural landscapes of Indiana

Fisher, Katelin Rose 25 February 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Riparian buffers have well documented capacity to remove nitrate (NO3-) from runoff and subsurface flow paths, but information on field-scale N2O emission from these buffers is lacking. This study monitored N2O fluxes at two agricultural riparian buffers in the White River watershed (Indiana) from December 2009 to May 2011 to assess the impact of landscape and hydrogeomorphologic factors on emission. Soil chemical and biochemical properties were measured and environmental variables (soil temperature and moisture) were monitored in an attempt to identify key drivers of N2O emission. The study sites included a mature riparian forest (WR) and a riparian grass buffer (LWD); adjacent corn fields were also monitored for land-use comparison. With the exception of net N mineralization, most soil properties (particle size, bulk density, pH, denitrification potential, organic carbon, C:N) showed little correlation with N2O emission. Analysis of variance (ANOVA) identified season, land-use (riparian buffer vs. crop field), and site geomorphology as major drivers of N2O emission. At both study sites, N2O emission showed strong seasonal variability; the largest emission peaks in the riparian buffers (up to 1,300 % increase) and crop fields (up to 3,500 % increase) occurred in late spring/early summer as a result of flooding, elevated soil moisture and N-fertilization. Nitrous oxide emission was found to be significantly higher in crop fields than in riparian buffers at both LWD (mean: 1.72 and 0.18 mg N2O-N m-2 d-1) and WR (mean: 0.72 and 1.26 mg N2O-N m-2 d-1, respectively). Significant difference (p=0.02) in N2O emission between the riparian buffers was detected, and this effect was attributed to site geomorphology and the greater potential for flooding at the WR site (no flooding occurred at LWD). More than previously expected, the study results demonstrate that N2O emission in riparian buffers is largely driven by landscape geomorphology and land-stream connection (flood potential).
16

Coupled biogeochemical cycles in riparian zones with contrasting hydrogeomorphic characteristics in the US Midwest

Liu, Xiaoqiang 11 December 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Numerous studies have investigated the fate of pollutants in riparian buffers, but few studies have focused on the control of multiple contaminants simultaneously in riparian zones. To better understand what drives the biogeochemical cycles of multiple contaminants in riparian zones, a 19-month study was conducted in riparian buffers across a range of hydrogeomorphic (HGM) settings in the White River watershed in Indiana. Three research sites [Leary Webber Ditch (LWD), Scott Starling (SS) and White River (WR)] with contrasting hydro-geomorphology were selected. We monitored groundwater table depth, oxidation reduction potential (ORP), dissolved oxygen (DO), dissolved organic carbon (DOC), NO3-, NH4+, soluble reactive phosphorus (SRP), SO42- , total Hg and methylmercury (MeHg). Our results revealed that differences in HGM conditions translated into distinctive site hydrology, but significant differences in site hydrology did not lead to different biogeochemical conditions. Nitrate reduction and sulfate re-oxidation were likely associated with major hydrological events, while sulfate reduction, ammonia and methylmercury production were likely associated with seasonal changes in biogeochemical conditions. Results also suggest that the LWD site was a small sink for nitrate but a source for sulfate and MeHg, the SS site was a small sink for MeHg but had little effect on NO3-, SO42- and SRP, and the WR was an intermediate to a large sink for nitrate, an intermediate sink for SRP, and a small source for MeHg. Land use and point source appears to have played an important role in regulating solute concentrations (NO3-, SRP and THg). Thermodynamic theories probably oversimplify the complex patterns of solute dynamics which, at the sites monitored in the present study, were more strongly impacted by HGM settings, land use, and proximity to a point source.
17

Selected population characteristics of smallmouth bass and rock bass in a three county area of the West Fork of the White River, Indiana from 1991-1994

Foy, Joseph P. January 2000 (has links)
Several population characteristics were calculated for smallmouth bass Micropterus dolomieui and rock bass Ambloplites rupestris populations on the west fork of the White River in Randolph, Delaware, and Madison counties, Indiana and were compared to other populations. When compared to streams of similar size in Indiana that were sampled with the same methods, relative abundance (CPUE) of smallmouth bass was average (18.9-35.0 fish/hour) while rock bass were two to ten times more abundant (44.3-53.0 fish/hour). Age analysis and back calculation of length at age were only performed for smallmouth bass. These results indicated strong year classes were cyclical and smallmouth bass growth was above average for Indiana streams, but average for streams of the Midwest. Proportional stock density values were average for smallmouth bass (28-39%) and slightly below average for rock bass (17-33%). Strong weight-length models were also found for both species and relative weight values were optimal. / Department of Biology
18

A chemical and physical profile of White River-1975

Posavec, Steven J. January 1976 (has links)
When sampling natural waters for constituent analyses, it is essential that a representative sample be obtained. This sampling survey was undertaken to study the effect of sampling depth on analyses as well as obtain useful data from the White River.Samples at three depths were collected at one location on the White River during two five-week periods. These samples were analyzed for the following constituents: total alkalinity, chloride, apparent color, calcium hardness, magnesium hardness, total hardness, tonal iron, ammonia nitrogen, nitrate nitrogen, dissolved oxygen, orthophosphorus, total inorganic phosphorus, total phosphorus, specific conductance, sulfate, and turbidity.The results indicated that sample depth is not a factor in the majority of the analyses described. For certain constituents, such as chloride and ammonia, however, sample depth is a factor to be considered. This survey also provided additional data on White River water quality and indicated that precipitation affected constituent concentrations.
19

Assesment [sic] of water quality parameters in the West Fork of the White River in Muncie, Delaware County, Indiana / Assesment of water quality parameters in the West Fork of the White River in Muncie, Delaware County, Indiana / Assessment of water quality parameters in the West Fork of the White River in Muncie, Delaware County, Indiana

Asbaghi, Navid January 2007 (has links)
Water quality parameters including ammonia, nitrate+nitrite, phosphate, total suspended solids, Escherichia coli, and dissolved oxygen were statistically evaluated from sampling data collected by the Bureau of Water Quality (City of Muncie, Indiana) at five sampling locations in Delaware County over a five-year period (2002-2006). These data were also compared with water quality standards/guidelines to determine how sample values compared to acceptable levels of these parameters. Friedman's non-parametric test was used to study the differences between sites and seasons. Spearman's Rank Correlation was used to study the correlations between water quality parameters at each sampling site. Significant differences were observed for individual parameters when evaluated relative to sampling location based on pooled monthly collected data as well as data evaluated on a seasonal basis. These differences indicated the fact that different sources were responsible for observed concentrations at a particular location and that seasonal phenomenon such as precipitation, discharge and temperature also affected sample concentrations at individual sampling locations. Most notable were differences in geometric mean concentrations of ammonia, nitrate+nitrite, phosphate and E. coli upstream and downstream of the wastewater treatment plant (WWTP), with highest concentrations downstream, indicating the significant impact of the WWTP on water quality in the White River. Significant correlations observed among some study parameters suggested that sample concentrations may have been affected by similar sources. In comparison to water quality standards, concentrations of ammonia, nitrate+nitrite, phosphate, and E. coli were at unacceptable levels at most sampling locations. / Department of Natural Resources and Environmental Management
20

Relationship of nutrients and pesticides to landuse characteristics in three subwatersheds of the upper White River, IN

Goward, Kelly J. January 2004 (has links)
Stream samples were tested at 18 sites in three subwatersheds of the Upper White River for ammonia, nitrate, orthophosphate, atrazine, and diazinon. Nutrient results were tested with a general linear model and in linear regressions with selected landuse characteristics. A critical areas index for surface runoff of pollutants was created using a geographic information system. Comparisons were made between results obtained by Ball State University and by the Muncie Bureau of Water Quality and other outside laboratories. Most mean concentrations of nutrients were likely related to combinations of agricultural and residential landuse factors. Only concentrations of ammonia and orthophosphate were significantly related (a = 0.05) to any landuse characteristics. Atrazine levels were high in the spring, but decreased in the fall. Results suggest that improved or increased best management practices should be implemented in these subwatersheds to control non-point source pollution of the streams. / Department of Natural Resources and Environmental Management

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