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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.
1

Total suspended solids, discharge, conductivity, and nutrients in three watersheds of the Upper White River, IN

Xu, Kejun January 2004 (has links)
Three watersheds of Upper White River were chosen for this study. Stream samples were tested for total suspended solids and conductivity. Fourteen percent of the total suspended solids samples were above 80 mg L-1 which can cause negative effects to aquatic life. Total suspended solids results were tested with a general linear model and in linear regressions with discharge and nutrients. Conductivity results were tested with a general linear model. Concentrations of the total suspended solids were significantly related to watershed, Julian date, the interaction of watershed and Julian date, and discharge. Increasing total suspended solids concentrations were significantly related to increasing concentrations of orthophosphate, nitrate, and ammonia. Conductivity levels were significantly related to watershed, location within watershed, and Julian date. Total suspended solids, discharge, and nutrient concentrations were high in the spring, but decreased in the following seasons. / Department of Natural Resources and Environmental Management
2

Assessing the impact of urbanization on White River water and sediment geochemistry in an agricultural watershed

Snidow, Dean C. January 2009 (has links)
Increased urbanization in the United States and the rest of the world, has led to more research on the effects it has on the local ecology. Urbanization can be defined as the creation of impervious cover in areas previously covered by natural vegetation (forest, grassland or farmland) as well as the potential influence of sewage treatment plants. Small increases in impervious cover can cause noticeable changes in stream chemistry. The goal of this study is to quantify the impact of smaller industrial cities on water and sediment geochemistry in a largely agricultural watershed. The study area is in east-central Indiana along the west fork of the White River and includes the cities of Winchester, Muncie and Anderson. This area is dominated by agriculture and the impact of cities in the region on water chemistry has not been studied. To evaluate this impact, sampling sites were selected up- and downstream of the three cities to characterize White River water chemistry before and after it flows through the cities as well as sewage treatment plants. Sampling was done over the course of one year to obtain samples characteristic of high and low flow river conditions. Samples were analyzed for major cation and anion concentrations as well as total suspended solids. Metals data was also obtained in sediments, although sampled only twice throughout the study. Results show that sediment load, on average, increases on the downstream side as the river flows through urbanized areas. Chemical analyses show that major cations and anions, Na, K, SO4 and Cl, have distinct spikes in concentration on the downstream side of the cities, as well. Na and Cl are specifically linked to human and urbanized activity, and were up to four times higher downstream of urbanized cities. The concentration of other major ions, including Ca, Mg and NO3, was mostly due to agricultural land use and local bedrock geology. Trace metals characteristic of pollution from automobiles, including Cd, Cr and Zn, showed large increases downstream of urban areas as well. This indicates that even in an area that is largely dominated by agriculture, smaller cities have a quantifiable impact to White River water quality. / Department of Geology
3

Impact of land cover and antecedent moisture content on runoff discharge in the West Fork of the upper White River, Indiana

Al-Mefleh, Naji K. January 2003 (has links)
There is no abstract available for this dissertation. / Department of Natural Resources and Environmental Management
4

Effect of certain physical and chemical parameters on analytical data for the White River

Sailor, Michael A. January 1975 (has links)
Currently it is common practice to conduct the environmental analysis of river water on randomly collected samples. Since rivers are considered to be continuously mixing, these waters are assumed to be homogeneous and therefore, the samples representative. This sampling parameter study was established to test that assumption.Three proximal points were established on the White River at Muncie, Indiana and sampled daily for twenty-five days. The samples were monitored for twenty-one different constituents: Alkalinity, chloride, color, calcium hardness, magnesium hardness, total hardness, total iron, ammonia nitrogen, nitrate nitrogen, nitrite nitrogen, dissolved oxygen, pH, orthophosphate, total phosphate, specific conductance, sulfate, turbidity, and temperature, using the Hach DR/EL-2 water analysis kit.The results indicated that thorough mixing is present and that homogeneity does exist for some constituents. However, the data also indicate that for some constituents homogeneity within the river does not exist. The significance of sampling frequency and the correlation of some of the interrelated chemical changes which occurred during the study are also discussed.
5

Abundance of nonprescription pharmaceuticals in central Indiana streams and effects on sediment microbial activity

Bunch, Aubrey R. January 2009 (has links)
Access to abstract permanently restricted to Ball State community only / Indirect effects of human population growth on stream ecosystem function : sediment respiration and nutrient uptake response to nonprescription pharmaceuticals -- Frequency and distribution of nonprescription pharmaceuticals in central Indiana streams. / Access to thesis permanently restricted to Ball State community only / Department of Biology
6

Examining ecosystem structure and disparity through time using geometric morphometrics

Grass, Andy Darrell 01 December 2009 (has links)
Functional morphology and morphometric studies on various mammalian groups have shown marked differences in crania and mandible shape based on dietary preferences and feeding habits. In this study I used three-dimensional geometric morphometric methods to measure the shape of crania and mandibles of herbivorous and omnivorous mammals from three formations in northwestern Nebraska to explore the structure and disparity of ecosystems through time: The White River Group (Chadronian/Orellan/Whitneyan), the Arikaree Group (Arikareean), and the Ogallala Group (Hemingfordian/Barstovian/Clarendonian). Throughout the time period compromising these formations the climatic conditions were becoming more arid, grasslands were expanding and the large mammalian faunal compositions were shifting from browser dominated to grazer dominated. Relative warps analysis show a visible separation of faunas between the three formations that cannot be attributed to phylogeny in plots based on either the crania or the mandibles. Phylogenetic effects were taken into account using generalized least squares. These results indicate that it may be possible to differentiate fossil taxa from different formations and environments based on the shape of cranial and mandibular elements as well as to infer the environment or diet of a fossil if other unequivocal data are not available.
7

Land cover effects on water quality and biotic integrity in the upper White River Basin, Indiana

Wright, Andrew W. January 2005 (has links)
The aquatic ecology of the White River basin has been studied since 1875 with researchers having reported 158 fish species belonging to 25 families. Recently, an EPA 319 grant allowed for further research in the Upper White River basin. The two-year study (2002-2004) examined three watersheds in Delaware County for biotic integrity, habitat quality, and stream water quality parameters. Twenty-two sites were selected to gain a perspective on agricultural, urban, and wooded landscape influences in order to locate and implement Best Management Practices (BMPs). Samples exceeded established state regulations and guideline criteria as follows: E. col/ (80%), ammonia-N (71%), dissolved oxygen (55%), nitrate+nitrite-N (38%), orthophosphate (33%), and total suspended solids (18%). A general linear model indicated that the effects of watershed and location within each watershed were significant (p <0.001) for both the Qualitative Habitat Evaluation Index (QHEI) and Index of Biotic hntegrity (IBI) index scores. Digitized land cover developed using Geographic Information Systems (GIS) was created to determine the effects of agricultural and wooded land cover ratios on the IBI and QHEI indices. A significant positive linear relationship between the amount of woodland land cover in a 5-m streamside riparian buffer and QHEI (p<0.001, r2 = 0.55) and with IBI (p<0.001, r-2 = 0.49) was found. A significant negative linear relationship was found with the amount of agricultural land in the created 5-m riparian buffer and IBI (p<0.001, r' 0.41), QHEI (p<0.001, r2 _- 0.36). The 30-nm streamside riparian buffer and delineated subwatershed land cover ratios were significant for the biotic integrity and habitat quality parameters, but were less predictive than the 5-m buffers. In addition, the amount of high runoff soils in the subwatersheds had significant negative effects on the IBI (p < 0.001, r' = 0.47) and QHEI (p = <0.001,r' = 0.43). Wetness accumulation and soil erosion was modeled in each watershed with the use of GIS, soils, and terrain parameters. The maps produced detailed locations where BMPs (wetlands, grassed waterways, riparian buffer strips etc.) could be targeted to reduce non-point source pollutants. / Department of Natural Resources and Environmental Management
8

Temporal variation of pharmaceuticals in Indiana streams and degradation potential by sediment microbial communities

Veach, Allison M. 09 July 2011 (has links)
This study examined temporal variation of pharmaceutical concentrations in two streams with differing land uses: 1) a suburban stream with combined sewer overflow point sources; and, 2) a rural stream influenced by septic systems and agricultural runoff. Sites were sampled monthly for pharmaceutical concentrations and stream physiochemical parameters. Pharmaceuticals were frequently detected in both the urban and agricultural stream with the highest concentrations measured during winter. Across sites, water column dissolved oxygen concentrations positively correlated with several pharmaceuticals suggesting microbial activity is important in pharmaceutical persistence. Potential for degradation of pharmaceuticals as a carbon or nitrogen source by stream sediment microbial communities was also estimated using pharmaceutical-amended basal salt media incubated under different temperature and ultraviolet (UV) light treatments. Under 4°C incubation, caffeine and acetaminophen were the most recalcitrant compounds whereas cotinine was the most labile. Under UV-B exposure, cotinine and sulfamethoxazole were the most recalcitrant compounds whereas ibuprofen was the most labile. / Temporal variation of pharmaceuticals in an urban and agriculturally influenced stream -- Degradation potential of six pharmaceuticals by sediment microbial communities. / Department of Biology
9

SPECIFIC GAGE ANALYSIS ON THE LOWER WHITE RIVER, ARKANSAS

Shaffner, Adam Levis 01 December 2012 (has links)
This study documents the stage adjustments in the Lower White River between 1931 and 2012 at four rated gaging stations along the trunk stem of the river. The study reach extends from Calico Rock, Arkansas, to the confluence of the White River with the Mississippi River north of Arkansas City, a distance of about 509 km. The specific gage approach was used to track hydrological response in the study reach. In order to approach spatial homogeneity across the four gaging locations along the study reach, input discharges were normalized to multiples of mean daily flow (MDF). Specific gage analysis tracks water surface elevation changes for fixed discharge conditions over time. Three discharges were analyzed at each station: low flow, mean flow, and high flow. The low flow specific gage trends are emphasized to highlight degradation and aggradation due to the sensitivity of specific stages at low flows to channel bed elevation changes. An `enhanced interpolation' technique was used to fill gaps in the specific stage time series in order to avoid errors derived from extrapolation of annual rating curves. The analysis shows decreasing trends in specific stage at Clarendon and DeValls Bluff at low flows, indicating net degradation. The gages at Newport and Calico Rock show increasing trends in specific stage over time at low flows, indicating aggradation downstream of Norfork and Bull Shoals reservoirs.
10

The rehabilitation of a sand and gravel-excavated site for recreational use : (Marion-Hamilton Counties, Indiana)

Lappas, Robert M. January 1981 (has links)
This study was designed to address the issues germaine to the land planning and rehabilitation strategy of a surface-mined land area for reuse as a water-based recreational facility. This development, the White River Waterpark, is proposed as a regional level facility.The report is divided into three sections. The first introduces the notion of rehabilitation as a necessary consideration for efficient land use planning. The second section provides background material on the process and methods of sand and gravel excavation and the resultant features which affect rehabilitation and reuse. Section three presents the design process for the Waterpark beginning with the formulation of planning objectives for facilities and activities, an inventory of the existing land base and an analysis of site features. These stages allow the determination of development and land use recommendations and conceptual design plans. Each stage of the planning process is documented in written and graphic form explaining the basis for decisions and proposals articulated in the Land Use Master Plan and supportive documents. / Department of Landscape Architecture

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