Dissertations / Theses: 'Mississippi (rivier)'

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O'Donnell, Thomas Kevin. "River restoration in the upper Mississippi River Basin." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4532.

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Thesis (M.S.) University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 27, 2007) Includes bibliographical references.

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2

Lipo, Carl P. "Science, style and the study of community structure : an example from the Central Mississippi River Valley /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/6558.

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3

Gooch, Catherine. "“I’VE KNOWN RIVERS:” REPRESENTATIONS OF THE MISSISSIPPI RIVER IN AFRICAN AMERICAN LITERATURE AND CULTURE." UKnowledge, 2019. https://uknowledge.uky.edu/english_etds/97.

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My dissertation, titled “I’ve Known Rivers”: Representations of the Mississippi River in African American Literature and Culture, uncovers the impact of the Mississippi River as a powerful, recurring geographical feature in twentieth-century African American literature that conveys the consequences of capitalist expansion on the individual and communal lives of Black Americans. Recent scholarship on the Mississippi River theorizes the relationship between capitalism, geography, and slavery. Walter Johnson’s River of Dark Dreams: Slavery and Empire in the Cotton Kingdom, Sven Beckert’s Empire of Cotton: A Global History, and Edward Baptist’s The Half Has Never Been Told: Slavery and the Making of American Capitalism examine how enslaved black labor contributed to the expansion of capitalism in the nineteenth century, but little is known about artistic representations of the Mississippi in the twentieth century. While scholars point primarily to the Mississippi River’s impact on slavery in the nineteenth century, I’ve Known Rivers reveals how black writers and artists capture the relationship between slavery, capitalism, and the Mississippi River. I consider a wide variety of texts in this study, from Richard Wright’s Uncle Tom’s Children and early 20th century Blues music, to late 20th century novels such as Toni Morrison’s Sula. This broad array of interdisciplinary texts illustrates a literary tradition in which the Mississippi’s representation in twentieth-century African American literature serves as both a reflection of the continuously changing economic landscape and a haunting reminder of slavery’s aftermath through the cotton empire. Furthermore, I’ve Known Rivers demonstrates how traumatic sites of slavery along the river are often reclaimed by black artists as source of empowerment, thereby contributing a long overdue analysis of the Mississippi River in African American literature as a potent symbol of racial progress.

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4

Pereira, Joao Miguel Faisca Rodrigues. "Numerical Modeling of River Diversions in the Lower Mississippi River." ScholarWorks@UNO, 2011. http://scholarworks.uno.edu/td/1309.

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The presence of man-made levees along the Lower Mississippi River (MR) has significantly reduced the River sediment input to the wetlands and much of the River's sediment is now lost to the Gulf of Mexico. The sediment load in the River has also been decreased by dams and river revetments along the Upper MR. Freshwater and sediment diversions are possible options to help combat land loss. Numerical modeling of hydrodynamics and sediment transport of the MR is a useful tool to evaluate restoration projects and to improve our understanding of the resulting River response. The emphasis of this study is on the fate of sand in the river and the distributaries. A 3-D unsteady flow mobile-bed model (ECOMSED; HydroQual 2002) of the Lower MR reach between Belle Chasse (RM 76) and downstream of Main Pass (RM 3) was calibrated using field sediment data from 2008 – 2010 (Nittrouer et al. 2008; Allison, 2010). The model was used to simulate River currents, diversion sand capture efficiency, erosional and depositional patterns with and without diversions over a short period of time (weeks). The introduction of new diversions at different locations, e.g., Myrtle Grove (RM 59) and Belair (RM 65), with different geometries and with different outflows was studied. A 1-D unsteady flow mobile-bed model (CHARIMA; Holly et al. 1990) was used to model the same Lower MR reach. This model was used for longer term simulations (months). The simulated diversions varied from 28 m3/s (1, 000 cfs) to 5, 700 m3/s (200, 000 cfs) for river flows up to 35, 000 m3/s (1.2x106 cfs). The model showed that the smaller diversions had little impact on the downstream sand transport. However, the larger diversions had the following effects: 1) reduction in the slope of the hydraulic grade line downstream of the diversion; 2) reduction in the available energy for transport of sand along distributary channels; 3) reduced sand transport capacity in the main channel downstream of the diversion; 4) increased shoaling downstream of the diversion; and 5) a tendency for erosion and possible head-cutting upstream of the diversion.

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Pearcy, Matthew Todd 1967. "A History of the Mississippi River Commission, 1879-1928: from Levees-Only to a Comprehensive Program of Flood Control for the Lower Mississippi Valley." Thesis, University of North Texas, 1996. https://digital.library.unt.edu/ark:/67531/metadc277642/.

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In 1879 Congress created the Mississippi River Commission (MRC) to develop and coordinate federal flood control policy for the Lower Mississippi River. Through 1927, that Commission clung stubbornly to a "levees-only" policy that was based on the mistaken belief that levees alone could be effective in controlling the flood waters of the Mississippi River. When the levees failed--and they occasionally did--the MRC responded by raising and strengthening the system but refused to adopt a more comprehensive program, one which would include outlets and reservoirs. Finally, a disastrous flood in 1927 forced the abandonment of levees-only and the adoption of a comprehensive plan for the Lower Mississippi River. Predictably, the MRC faced heavy criticism following the failure of its highly-touted levee system in 1927. While certainly the Commission was culpable, there was plenty of fault to go around and a plethora of mitigating circumstances. Developing a plan for achieving adequate flood control along the lower Mississippi River constituted what was probably the most difficult and complex engineering problem ever undertaken by the U. S. Government. Additionally, there were innumerable political and financial constraints that worked to shape MRC policy. This study will endeavor to tell the story of the MRC from its earliest origins through the landmark 1928 Flood Control Act, and, in the process, give evidence to the reality that the Commission did not function independently. As an organization, it relied upon outside forces for its membership, for its jurisdiction, and for the appropriations necessary to carry out its policies. Significantly, these forces were politically driven and did not always, or even often, share the MRC's priorities for the Lower Mississippi River. Even so, the MRC accomplished a great deal in its efforts to protect the Valley from moderate floods, to improve the navigability of the Mississippi River, and to expand significantly the body of knowledge available on the "Father of Waters."

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Smith, Thomas Ruys. "Ultima Thule : antebellum representations of the Mississippi River." Thesis, University of East Anglia, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423576.

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7

Esposito, Christopher. "Differential Sedimentation In A Mississippi River Crevasse Splay." ScholarWorks@UNO, 2011. http://scholarworks.uno.edu/td/1308.

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In this study the patterns of sediment transport and deposition in the channels and receiving basin of a crevasse splay in the modern Mississippi River delta are examined, with emphasis on the development of a distributary mouth bar. Simultaneous hydroacoustic and optical measurements on the mouth bar show that the bar conforms to the progradational stage of an existing conceptual model of mouth bar development. This is confirmed by cores dated using Beryllium-7, which provides a record of the deposition on the bar over a 90-day period. Stratigraphic data from cores obtained on the bar are used to extend the conceptual model to account for variable riverine inputs. A numerical model, developed and validated using field data is capable of representing the fundamental sedimentary processes responsible for mouth bar progradation. These results will be of interest to coastal geologists, engineers and coastal managers alike.

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Maurer, Edwin P. "Predictability of runoff in the Mississippi River Basin /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/10120.

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9

Slay, David Henson. "New masters on the Mississippi the United States colored troops of the middle Mississippi Valley /." [Fort Worth, Tex.] : Texas Christian University, 2009. http://etd.tcu.edu/etdfiles/available/etd-05012009-121518/unrestricted/Slay.pdf.

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10

Zhu, Yan Carleton University Dissertation Geography. "Water quality of the South Nation River, Rideau River and Mississippi River; a statistical survey." Ottawa, 1993.

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11

Clauson, Karen D. "Measuring Trends In Riverbed Gradation: A Lower Mississippi River Case Study." OpenSIUC, 2009. https://opensiuc.lib.siu.edu/theses/75.

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The trends of degradation and aggradation are measured in this study for the Lower Mississippi River. Historical riverbed elevation and stage data from the past hundred years were used from six gages in order to measure changes in riverbed gradation. It was found that using stage data to measure gradation changes is a superior method to using riverbed elevations, due to stage data’s reliability, length of record and daily measurements. Degradation in the Lower Mississippi River was seen during the

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12

Gurung, Tshering T. "One-Dimensional Dynamic Modeling of the Lower Mississippi River." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1804.

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The Mississippi River (MR) has been engineered with the development of the levee system, dams for flood control measures, jetties, revetments and dredging of the navigation channel. These alterations have reduced the replenishment of the sediment to the Louisiana Coastal area. To aid in the restoration planning, 1-D numerical models have been calibrated and validated to predict the river response to various changes such as channel modifications, varied flow conditions and hurricane situations. This study utilized the HEC-RAS 4.1 and the CHARIMA (Dr. Forrest Holly, University of Iowa). The models were calibrated for hydrodynamics and sediment using Tarbert Landing discharges (HEC-RAS), Belle Chasse sand concentrations (CHARIMA), and Gulf of Mexico (GOM) stages. The models showed that a large percentage of the river flow is lost over the East Bank downstream of Bohemia which reduces the sand transport capacity of the river. This reach is subject to flow reversals during hurricanes.

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13

Harmar, Oliver Philip. "Morphological and process dynamics of the Lower Mississippi River." Thesis, University of Nottingham, 2004. http://eprints.nottingham.ac.uk/10056/.

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This thesis uses data sets at a range of spatial and temporal scales to examine the geomorphological response of the Lower Mississippi River to engineering and management. During the twentieth century the geomorphology of the Lower Mississippi River has been transformed by a series of engineering modifications to improve flood control and aid navigation. These have included steepening of the longitudinal profile by removal of the most sinuous bends, fixing the river to a constant planform through extensive bank stabilisation, and regulating sediment movement through the channel system by dike field construction. Prior to these modifications, the Lower Mississippi River adjusted its planform morphology to satisfy large-scale flow resistance requirements. However, this mode of adjustment has been effectively removed and adjustments are now restricted to the long profile and cross-sectional form. Morphological analysis reveals that the river has responded to engineering intervention at two principal scales: by vertical changes in the elevation of the channel bed at the reach-scale; and by increasing large-scale bedform resistance at the sub-reach scale through longitudinal and cross-sectional adjustments. These mutual changes are consistent with the changes in water surface elevation in the post-modification period noted by Biedenharn and Watson (1997). However, analysis of morphological and process dynamics at shorter timescales shows that geomorphological response remains difficult to explain. This is because geomorphological behaviour at any scale, and in any location within an alluvial channel, is a product of complex spatially-distributed feedbacks between operating processes and multiple scales of channel morphology. This has general significance in terms of research design because detecting the complexity at each scale of adjustment, and forming linkages between scales of adjustment, is dependent on taking into account all possible degrees of freedom, and applying a range of complementary analytical techniques.

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14

Banerjee, Malini De. "High-Frequency Nitrate Monitoring in Dynamic River Systems: the Case of Three Iowa Rivers in the Mississippi Basin." Diss., University of Iowa, 2013. https://ir.uiowa.edu/etd/4818.

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High frequency water quality monitoring presents unique and unlimited opportunities of exploring spatio-temporal variation in water quality. Knowledge gained from analyzing high frequency water quality data can provide more clarity regarding transportation and processing of water constituents over time and space and scale. This study analyzes high frequency discharge, nitrate load and concentration data for three watersheds of different sizes - Cedar River Watershed, North Raccoon and Middle Raccoon. Each of these sites were monitored for 2-3 calendar years. Sudden spikes in discharge, nitrate concentration and load data, also defined as "events" were analyzed in great detail to understand the patterns in event occurrence and event intensity. Smaller watersheds seemed to have sharper and "flashier" events compared to bigger watersheds. Nitrate concentration events were flatter in shape compared to discharge and nitrogen load events. The relationship between nitrogen concentration and discharge was found to be varying over time, unlike the relationship between nitrate load and discharge, which were almost perfectly correlated for most site-year combinations. Based on more than 40,000 simulations, it was determined that high frequency water quality sampling is not only efficient in capturing minute spatio-temporal variations but can also capture nitrate exceedances to a greater degree. High frequency sampling was also associated with higher yield ratio in nitrate load estimates, not only during high flow periods, but also during the non-high-flow period.

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15

Davis, Mallory. "Numerical Simulation of Unsteady Hydrodynamics in the Lower Mississippi River." ScholarWorks@UNO, 2010. http://scholarworks.uno.edu/td/1126.

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Alterations along the Mississippi River, such as dams and levees, have greatly reduced the amount of freshwater and sediment that reaches the Louisiana coastal area. Several freshwater and sediment diversions have been proposed to combat the associated land loss problem. To aid in this restoration effort a 1-D numerical model was calibrated, validated, and used to predict the response of the river to certain stimuli, such as proposed diversions, channel closures, channel modifications, and relative sea level rise. This study utilized HEC-RAS 4.0, a 1-D mobile-bed numerical model, which was calibrated using a discharge hydrograph at Tarbert Landing and a stage hydrograph at the Gulf of Mexico, to calculate the hydrodynamics of the river. The model showed that RSLR will decrease the capacity of the Lower Mississippi River to carry bed material. The stage at Carrollton Gage is not significantly impacted by large scale diversions

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16

Wessels, Scott. "Late Quaternary Mississippi River Incised Valley Fill: Transgressive Depositional Packages." ScholarWorks@UNO, 2010. http://scholarworks.uno.edu/td/1236.

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A series of USACE atlas quadrangles and dee pborings from the USGS and LGS with radiocarbon dated peats were used to construct several regional crosssections and paleogeographic reconstructions. Late Pleistocene glaciation and consequent lowered sea leve lresulted in reentrenchment of the Mississippi River incised valley. Meltwater floods from proglacial lakes incised into older deposits followed by braided fluvial (substratum) aggradation due to reduced carrying capacity after floods followed by meandering fluvial(topstratum aggradation as fluvial gradients and discharge decreased. Rapidly rising sea level prevented development of shelf phase deltas prior to~10ka. Attenuated rates of sea level rise and periodic avulsions led to development and subsequent abandonment of several shelf phase deltas and barrier island arcs as well as gradual encroachment of the top stratum up the alluvial valley as aggradational depositon filled available accommodation space.

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17

Ogbugwo, Marilyn C. "Channel migration and geology on the Chickasawhay River, southeast Mississippi." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0009467.

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18

Corcoran, Maureen Kathleen. "Geomorphic identification and verification of recent sedimentation patterns in the Woonasquatucket River North Providence, Rhode Island /." Full text available from ProQuest UM Digital Dissertations, 2006. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1260796661&SrchMode=1&sid=1&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1193255862&clientId=22256.

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19

Laaker, Dillan J. "Avian Use of Floodplain Forest Communities along the Upper Mississippi River." Thesis, Southern Illinois University at Edwardsville, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10808741.

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Floodplain forests along the Upper Mississippi River are known to provide valuable habitat for many species of migrating songbirds, including the Cerulean Warbler (Setophaga cerulea) and other species of concern. The forested islands of the confluence region where the Illinois and Missouri Rivers join the Mississippi vary greatly in their structure and composition, providing a variety of habitats for migrating bird species. While past studies have looked at the richness and diversity of bird species across gradients of forest structure, very few have determined which species are characteristic of certain forest types. Effective management and conservation of these lands by state and federal agencies requires that managers understand patterns of species use in these different forest communities. The objectives of this study were (1) to discover how bird community composition varies throughout the floodplain, (2) to determine which vegetation factors, structural or floristic, influence the composition of bird communities, and (3) to identify any species indicative of certain habitat types. Using a protocol developed through a partnership with the U.S. Army Corps of Engineers—St. Louis District, the Audubon Center at Riverlands, and the Cornell Lab of Ornithology, 10 minute avian point count surveys were conducted from May 15 – June 30 at 95 survey points located throughout the forested areas of the Upper Mississippi River floodplain. Data collected during the 2017 surveys were added to point count data from the 2015 and 2016 survey seasons. An invaluable tool developed by the U.S. Army Corps of Engineers’ forestry division, the Forest Management Geodatabase (FMG) was used to analyze structural complexity and vegetation characteristics at each avian point count site, including canopy height, basal area, tree species richness, and understory height. Differences in bird species richness across values of canopy height, basal area, understory height, and tree species richness were explored and tested using single-factor ANOVA. Non-metric multidimensional scaling (NMDS) was used to summarize the pattern of avian community composition among sites and analysis of similarities (ANOSIM) tested for differences in avian communities among forest types. Bird species richness did not differ significantly across values of any of the four forest variables tested. NMDS and ANOSIM found that both canopy height and basal area significantly affected bird community composition while tree species richness and understory height had no effect. Indicator species analysis was then used to identify those species that characterized certain categories of canopy height and basal area. Indicator species analysis found 21 species to be indicators across four discreet categories of canopy height and 23 species to be indicators across 4 categories of basal area. Indicator species of note included five focal species: Indigo Bunting, Prothonotary Warbler, American Redstart, Warbling Vireo, and Red-shouldered Hawk. Warbling Vireos were indicators for sites with canopy heights less than 9 meters, while Prothonotary Warblers were characteristic of sites with the largest values of basal area (> 75 m²/ha). These focal species are chosen by the Audubon Center at Riverlands and are deemed important to the region or species of concern, making them targets of conservation. The knowledge of bird species-habitat relationships gained from this study is critical for the successful management of floodplain forest in order to benefit Neotropical migratory bird species on the Upper Mississippi River System.

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Clauson, Karen. "Measuring trends in riverbed gradation : a Lower Mississippi River case study /." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1797219591&sid=4&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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21

Jarvis, Stephanie. "Thecamoebians as an environmental proxy for the Middle Mississippi River floodplain." OpenSIUC, 2014. https://opensiuc.lib.siu.edu/theses/1566.

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Thecamoebian tests from recent lacustrine sediments have been shown to be a useful proxy to study environmental changes such as land-use changes, pollution, and climate shifts. In this study, the usefulness of thecamoebians as an environmental proxy for the Middle Mississippi River (MMR) floodplain is explored. Sediment cores and surface samples were collected from two sites in Alexander County, IL: Southern Illinois University's (SIU) MMR Wetland Field Station near East Cape Girardeau, IL and Horseshoe Lake, a dammed oxbow managed by the IL Department of Natural Resources (DNR), near Olive Branch, IL. These sites represent different floodplain environments, management histories, and flooding patterns. The thecamoebian populations were expected to reflect these differences while also responding to regional signals associated with development, agriculture, and climate. Cores were subsampled at a 5cm interval and all samples were sieved with 150μm and 45μm screens to retain thecamoebian tests. Sieved sediment was examined under a microscope and at least 100 tests were identified in each sample. Pre- and post-land clearing assemblages are recognized at each site, primarily by the increased abundance of the eutrophic-indicating species Cucurbitella tricuspis. Additionally, grab samples collected from the wetlands site during the spring indicate that the site may be influenced by road salt runoff in addition to agricultural activity. These results suggest that thecamoebians are a useful land-use change proxy and more research is needed to better understand the environmental conditions influencing assemblages.

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22

Knapp, Jennifer M. "Geology-based site coefficients for the Upper Mississippi Embayment." Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/21000.

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23

Gouw, Marc Jean Pierre. "Alluvial architecture of the Holocene Rhine-Meuse delta (The Netherlands) and the Lower Mississippi Valley (U.S.A.) /." Utrecht : Koninklijk Nederlands Aardrijkskundig Genootschap [u.a.], 2007. http://www.loc.gov/catdir/toc/fy0803/2008400359.html.

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24

Stephenson, Keith. "MISSISSIPPI PERIOD OCCUPATIONAL AND POLITICAL HISTORY OF THE MIDDLE SAVANNAH RIVER VALLEY." UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_diss/194.

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Research focusing on the political economy of Mississippian mound centers in the middle Savannah River valley has prompted a reevaluation of current interpretations regarding societal complexity. I conclude the clearest expression of classic Mississippian riverine-adaptation is evident at centers immediately below the Fall Line with their political ties to chiefdom centers in the Piedmont, and especially Etowah. By contrast, those centers on the interior Coastal Plain were politically autonomous with minimal signatures in social ranking. The scale of appropriated labor and resulting level of surplus production, necessitated by upland settlement on the Aiken Plateau, fostered social contradictions making communally-oriented and decentralized societies more sustainable than hierarchical forms.

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Calkins, Heather Ann. "Linking Silver Carp Habitat Selection to Phytoplankton Consumption in the Mississippi River." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/345.

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Since their introduction to the United States in the 1970s, the invasive silver carp (Hypothalmichthys molitrix) has migrated into the native waters of 16 states with populations in the Mississippi, Missouri, Ohio and Illinois River systems expanding at exponential rates in the past decade. As this species advances towards Lake Michigan, the threat of their invasion into the Laurentian Great Lakes is becoming very real. Silver carp are opportunistic, capable of rapid and extensive dispersal. They have the potential to compete with native species for critical habitat and food, which are very important limiting resources in all freshwater systems. Understanding their diet and habitat selection could be helpful for predicting their expansion and impacts in systems they invade. In order to fully understand habitat selection, 77 silver carp were implanted with ultrasonic transmitters during Spring 2008 and Spring 2009 in Pools 26 (N=24) and 27 (N=53) of the Mississippi River. Fish were located monthly to assess macrohabitat use. To determine if phytoplankton availability was influencing habitat selection, environmental chlorophyll a (used as a surrogate for phytoplankton abundance) was quantified monthly at silver carp detection sites and at randomly generated points from all macrohabitats. 240 silver carp were sacrificed to analyze foregut chlorophyll a concentrations (Pool 26 N=141; Pool 27 N=99); chlorophyll a concentrations in the river at fish locations were measured. This allows us to determine utilization of available phytoplankton resources. Silver carp were detected mostly in channel border wing dike areas with island side channel also being a popular macrohabitat. Chlorophyll a concentrations in the river were higher in areas where carp were detected compared to random sites across all macrohabitat types (Ksa=1.28 p=0.080). There was no significant relationship between foregut chlorophyll a concentrations and what was available in the environment, suggesting silver carp are using resources similarly across all habitats. Given that this species accumulated high concentrations of phytoplankton in their guts even in areas of low phytoplankton concentrations, they may be able to successfully invade areas with scarce phytoplankton resources.

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Flinn, Michael Brainerd. "Biological responses in off-channel habitat to hydrologic gradients and river management practices in Mississippi River Pool 25 /." Available to subscribers only, 2006. http://proquest.umi.com/pqdweb?did=1140187751&sid=18&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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DePoy, Richard Mark. "Physical, chemical and biological factors affecting the survival of fingernail clams in pool 8, upper Mississippi River." Virtual Press, 1996. http://liblink.bsu.edu/uhtbin/catkey/1014860.

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1 examined the temporal and spatial distribution of total ammonia nitrogen (TAN) and un-ionized ammonia (NH,) in sediment pore water and compared the temporal and spatial patterns of TAN and NH, in overlying surface water with those in pore water, to determine if they were reaching concentrations known to be deleterious to fingernail clams. Pore water was obtained by core extraction and subsequent centrifugation. TAN and NI-I3 in pore water were measured from May through December 1994, at ninety two sites in pool 8, upper Mississippi River, to a depth of five centimeters below the sediment-water interface. TAN and NH3 in pore water were significantly different among sampling dates; with the greatest concentrations occurring in the summer months. Tan and N1-I3 in pore water was significantly greater in impounded open water and backwater side channel habitats and least in main channel border habitat. Tan and NH3 in surface water were significantly less than those in pore water from all of the habitats studied. Analysis of sediment substrate physical features, found that fingernail clam density and occupance were correlated to texture, with fingernail clams preferring silt loam and loam textures. Analysis of the data determined fingernail clams have a preference for particular water depths. It was found that a positive correlation exists between the occurrence and abundance of may flies and fingernail clams. Additionally, this study found a positive correlation between the density of dead fingernail clams (as per empty shells) and the abundance of live fingernail clams. Sites that contained a mean NI-I, concentration below 36 ug/L possessed the largest numbers of fingernail clams. When the mean un-ionized ammonia was above 36 ug/l, fingernail clam density declined precipitously-- 36 ug/L NH3 is the concentration demonstrated to inhibit growth of fingernail clams in laboratory studies. Mean concentrations of NH, in pore water at sites containing fingernail clams was 40 ug/L and ranged from 3 to 100 ug/L. At sites where fingernail clams were nonexistent, NH3 ranged from 3 to 375 ug/L with a mean of 57 ugfL. Mean un-ionized ammonia concentrations at sites containing fingernail clams were significantly different from and consistently lower than sites without fingernail clams.
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28

Schubert, Michael Andrew Weber Larry Joseph Young Nathan C. "Computational fluid dynamics applications for nitrate removal in an upper Mississippi River backwater." [Iowa City, Iowa] : University of Iowa, 2009. http://ir.uiowa.edu/etd/431.

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Yu, Tun-Hsiang. "Essays on the Upper Mississippi River and Illinois Waterway and U.S. grain market." Texas A&M University, 2003. http://hdl.handle.net/1969.1/2278.

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This dissertation examines several issues regarding the congestion on the Upper Mississippi River and Illinois Waterway. Chapter II identifies and measures the impact of lock congestion on grain barge rates on these waterways. Results indicate grain barge rates on both rivers are not affected by lagged lock congestion. In present time, however, lock congestion in the lower reaches of the upper Mississippi and Illinois Rivers are found to increase barge rates that link the north central United States to the lower Mississippi Gulf port area. The findings suggest the impact of lock congestion on grain barge rates is moderate. Chapter III explores the interaction between grain prices in export and domestic markets and transportation rates linking these markets over time. Three model frameworks were evaluated and some consistent results are observed. In general, shocks in transportation rates (barge, rail, and ocean) explain a great proportion of the variation in corn and soybean market prices in the long run, suggesting the importance of transportation in grain price determination. The volatile ocean freight rates are the mostimportant transportation rates contributing to the variation in grain prices, while shocks in barge rates on the Upper Mississippi River and Illinois Waterway generally explain less than 15 percent of the variation in grain prices. The dynamic interrelationships among the six evaluated transportation rates are also found. In addition, the north central corn markets likely have the most influence over other markets while soybean export price dominates the soybean market in the long run. Chapter IV estimates the structural demand for grain barge transportation on both the upper Mississippi and Illinois Rivers. Results suggest foreign grain demand is the most influential force affecting grain barge demand on both rivers. Also, results indicate an inelastic demand for grain barge transportation on the Upper Mississippi in the short run; demand is price elastic in the long run. The price elasticity for grain barge demand on the Illinois River is consistently inelastic. Additionally, the winter season and floods affect demand on the Upper Mississippi negatively, while barge demand increases on the Illinois River in winter.

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Koch, Jeff. "Effects of commercial harvest on shovelnose sturgeon populations in the upper Mississippi River." [Ames, Iowa : Iowa State University], 2008.

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Pavlyukova, Tatiana. "A 3-D Hydrodynamic Modeling at Head of Passes of the Mississippi River." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1827.

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A 3-D numerical model of the Head of Passes and Bird’s Foot Delta of the Mississippi River- was developed. The model was based on Delft3D and simulates the hydrodynamics and salinity transport for Head of Passes area from RM 6.5 to Gulf of Mexico. The model was calibrated, validated, and used to predict the response of the river to certain stimuli, such as - channel closures, channel modifications and diversions. The model includes West Bay, Southwest Pass, South Pass, Pass-A-Loutre and Main Pass. Three basic cases were developed: existing conditions, closure of Southwest Pass with a levee of 1.5m with dredging of Pass-A-Loutre to 13.7 meter depth, and closure of Southwest Pass and South Pass with dredging of Pass-A-Loutre to 13.7 meter (45 ft) depth. Salinity has been added to the model. It has been proved that salinity intrusion has a significant impact on the model instantaneous discharge. For all passes except Southwest Pass instantaneous discharge decreases almost in half. Closure of Southwest Pass and dredging of Pass-A-Loutre leads to changes in flow speed and distribution. As a result Pass-A-Loutre becomes a main River channel.

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Maulhardt, Alison. "Restoring the Mississippi River Delta in Louisiana Ecological Tradeoffs and Barriers to Action." ScholarWorks@UNO, 2015. http://scholarworks.uno.edu/td/2098.

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This study investigates the Louisiana 2012 Coastal Master Plan’s ability to reconcile conflicting economic and ecological demands on coastal resources. The Louisiana Coastal Master Plan was unique in combining flood control and coastal restoration under one authority. However, the objectives of flood control and coastal restoration can be in conflict. The plan was also unique in its approach of restoration from a working coast perspective. However, the objectives of ecological restoration and economic productivity do not always agree. By conducting semi-structured interviews with major coastal stakeholders, this research will explore how the planning process has accommodated the views and values of key stakeholder parties. This research aims to make more transparent the inherent environmental tradeoffs of restoration from a working coast perspective. A working coast is a compromise between economic and environmental stakeholder needs. The approach requires a balance of power to ensure that the projects selected best serve the needs of all parties. The study found that while there is industry buy in, mechanisms for mitigating economic externalities is lacking in the plan, corporate infrastructure benefits while wildlife resources are in decline.

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Szynkowski, Brittany Christine. "An examination of Asian carp spawning in pool 26 of the Mississippi River." OpenSIUC, 2013. https://opensiuc.lib.siu.edu/theses/1344.

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More knowledge about the spawning habits of the invasive silver (Hypophthalmichthys molitrix) and bighead (H. nobilis) carps in the United States could lead to a better understanding of how and where these fish are able to successfully reproduce and continue to expand their range. This study explored the possibility of combining multiple strategies (mobile tracking, catch-per-unit-effort [CPUE] of females, reproductive staging of females, and CPUE of larvae) to determine whether Asian carp were more likely to spawn in specific habitats. Additionally, I explored whether the timing of spawning was size-dependent for female Asian carp, and whether Asian carp larvae overlapped with those of native species in space and time. Adult females and larvae were collected weekly and transmittered adults were tracked generally monthly in Pool 26 of the Mississippi River during optimal spawning temperatures in 2011. Mixed model repeated-measures analyses indicated no effect of habitat on adult female or larvae CPUE. There were significant increases in Asian carp larvae CPUE on June 6 (t77 = 5.65, P < 0.001) and June 20 (t77 = 7.33, P < 0.001), indicating recent spawning bouts. Regression tree analysis found that the highest Asian carp larvae CPUE occurred at temperatures ¡Ý 22.5¡ãC and turbidities ¡Ý 163.5 NTU (0.50 larvae m-3). A multinomial baseline-category logit model suggested that there was a 0.83 probability of relocating a tagged fish in a backwater. Logistic regressions determined that 50% of silver carp females were mature at 688 mm total length and larger silver carp females had a higher probability of being spent earlier in the spawning season than smaller females. Asian carp represented 10% of all collected larvae and made up over half of the total larval catch on June 6, 2011. This study found little evidence suggesting that Asian carp are spawning in specific habitats. However, it is possible that the temporal collection pattern was too coarse to catch their potentially rapid response to spawning cues. Larger females may be contributing disproportionately to the population through early spawning, suggesting that population reduction could be increased by targeting these females.

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Schubert, Michael Andrew. "Computational fluid dynamics applications for nitrate removal in an upper Mississippi River backwater." Thesis, University of Iowa, 2009. https://ir.uiowa.edu/etd/431.

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This thesis details the work completed in order to develop a hydrodynamic and nitrate transport and reaction model for Round Lake, a backwater on UMR Pool 8. This work begins with investigating the fundamentals of nitrogen removal in aquatic ecosystems and reviewing other combined hydrodynamic and nutrient modeling efforts. Field data were gathered to determine model boundary conditions and provide a basis for calibration and validation. Using this data, the flow regime in Round Lake was simulated. CFD applications to model particle residence times and species transport and reaction were used to analyze the effects local hydraulics have on nitrogen removal in the lake. Results demonstrated an ability for CFD to predict spatial variation of nitrate with this ecosystem.

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Yocum, Tara A. "Growth laws for sub-delta crevasses in the Mississippi River Delta: observations and modeling." ScholarWorks@UNO, 2017. http://scholarworks.uno.edu/td/2339.

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In this study we assessed growth laws of sub-delta crevasses in the Mississippi River delta plain, experimental laboratory deltas, and compared them to previously studied river dominated large deltas worldwide. Metrics for channel and delta geometry for each system were obtained using a combination of geospatial tools, bathymetric datasets, sediment size, and hydrodynamic observations. Most crevasses and experimental deltas appear to obey delta growth laws suggesting that they exhibit planform metrics similar to larger deltas. However, some channels within each system, exhibit outlier behavior (e.g. asymmetric growth) where channel length is much larger than channel width. Hydrodynamic observations and morphodynamic modeling results, support the role of confinement in governing this response, through direct lateral confinement of the receiving basin width and depth thus guiding channels, and indirect confinement caused by sediment cohesion, whereby natural levees guide the systems asymmetric channel growth.

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36

Zeigler, John Matthew. "UTILITY OF OTOLITH MICROCHEMISTRY AND STABLE ISOTOPIC COMPOSITION FOR DETERMINING FISH ENVIRONMENTAL HISTORY IN THE MISSISSIPPI AND ILLINOIS RIVERS." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/230.

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Knowledge of habitats used by riverine fishes throughout their life history is important for management and conservation. Naturally occurring chemical markers in otoliths have recently been used to determine natal origins and environmental history of fishes in a variety of marine and freshwater environments. However, to our knowledge no studies have examined the applicability of this technique in large floodplain rivers in United States. We evaluated otolith microchemistry and stable isotopic composition as tools for determining origins of fishes in the upper and middle Mississippi and lower Illinois Rivers, their tributaries, and associated floodplain lakes. Fishes were collected from 21 sites during summer 2006 and 2 additional sites in spring 2007. Water samples were obtained from the same 23 sites plus three additional sites during summer and fall 2006 and spring 2007. Otoliths and water samples were analyzed for δ18O, and a suite of trace elements; otoliths were also analyzed for δ13C. Tributaries, floodplain lakes, and the Illinois and Mississippi Rivers had distinct isotopic and elemental signatures. Tributaries on the Missouri and Illinois sides of the middle Mississippi River could also be differentiated by their elemental and isotopic fingerprints. Otoliths reflected differences in water chemistry among habitats. Results indicate that otolith microchemistry and stable isotope analyses provide a potentially effective means of determining origins and environmental history of fishes in large river-floodplain systems.

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Gouw, Marc. "Alluvial architecture of the Holocene Rhine-Meuse delta (the Netherlands) and the Lower Mississippi Valley (U.S.A.) /." Utrecht : Koninklijk Nederlands Aardrijkskundig Genootschap, Faculteit Geowetenschappen Universiteit Utrecht, 2007. http://www.loc.gov/catdir/toc/fy0803/2008400359.html.

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Sinha, Sumit. "Parameter estimation and auto-calibration of the STREAM-C model." Master's thesis, Mississippi State : Mississippi State University, 2005. http://library.msstate.edu/content/templates/?a=72.

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39

Hitchcock, Arthur Neil. "Diets of spring-migrating waterfowl in the Upper Mississippi River and Great Lakes Region /." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1796330181&sid=6&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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40

Lenz, Rebecca Marie. "Iron, Arsenic, and Elevated Salinity in the Lower Mississippi River Alluvial Aquifer of Louisiana." Thesis, University of Louisiana at Lafayette, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10615017.

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The Lower Mississippi River Alluvial Aquifer (LMRAA) is a critical groundwater resource for Arkansas, Mississippi, and Louisiana. It is second only to the Ogallala aquifer in terms of the volume of groundwater pumped for irrigation. High concentrations of salinity, iron (Fe), and arsenic (As) affect several regions of the LMRAA. In this study, long-term geochemical changes in the LMRAA in Louisiana were evaluated to better understand the relationships among salts, Fe, and As. The geochemistry was investigated using historical data collected from the LDEQ and USGS. Data from the LDEQ were collected every three years from approximately 2001 to 2013. Major and some trace element data were available, including concentrations of sodium (Na), chlorine (Cl), magnesium (Mg), calcium (Ca), Fe, and As. These historical data were supplemented with recent (2016/2017) sampling and analysis of the isotopes of oxygen (δ¹⁸O) and hydrogen (δ²H). Geochemical results show that groundwater in the LMRAA in Louisiana can be characterized by two main groupings. The first group is generally characterized by a Na/Cl ratio close to one and/or higher salinity, while the second group is generally characterized by excess Na (relative to Cl) and tends to be more alkaline and rich in Fe. The highest salinity regions are spatially limited, and their extents appear to have remained stable over time. Areas of elevated salinity in the northeast part of the study area may be attributable to mixing of deeper salt-rich waters with the shallow groundwater system, while the salt-rich areas in the southern part of the study area are thought to be attributable to dissolution of salt domes. The waters potentially influenced by brines in the northeast are additionally characterized by higher Mg/Ca ratios. These waters are also enriched in δ¹⁸O relative to other areas of the LMRAA. There was no correlation between the areas of potential brine interaction and the concentrations of Fe or As. Instead, areas of high Fe concentration correlated spatially with areas of high alkalinity and the development of waters with excess Na (i.e., waters where Na is in substantial excess relative to the amount of chloride, and instead counterbalanced by HCO_3^-). Arsenic concentrations varied from below detection to 67.7µg/L at one location sampled by the LDEQ in 2010. Six of the approximately 25 wells historically sampled by the LDEQ as part of the ASSET program consistently had concentrations of As >10 µg/L. These locations generally correspond with the groundwater characterized by higher Fe, alkalinity, and Na-excess, but at the same time appear to be localized and often surrounded by wells with low concentrations of As. The concentrations of Fe and As were not correlated. This rather heterogeneous distribution of As contamination could point to anthropogenic influences or sources. The concentrations and spatial distributions of waters rich in salts, Fe, and As in the LMRAA appear to have remained relatively consistent for the last decade, even though demand for groundwater in the LMRAA of Louisiana has more than doubled over this time to 493 million gallons per day (in 2016).

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Heard, Haley R. (Haley Ruth). "Deconstructing the Mississippi River : restoring a continental system through the integration of flexible infrastructure." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59736.

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Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2010.
Vita. Cataloged from PDF version of thesis.
Includes bibliographical references (p. 100-102).
The most prevalent social and economic issues plaguing cities are symptomatic of much bigger underlying environmental problems. Cities are governed by legislation set within artificial political boundaries, however ecology systems surpass and are not restricted by these boundaries. The decisions urban designers and planners make on behalf of a city influences the natural environment, which in turn can affect other cities negatively. This thesis addresses the current disconnect between the way cities are planned, their artificial boundaries, and the larger, underlying ecological systems. The purpose of this research is to create new methods of design and planning from ecological scale thinking. This thesis uses the Mississippi River as a case to illustrate how ecological scale thinking can reframe present urban design and planning paradigm. The research aims to answer the following questions: What are the principal causes of the Mississippi River's ecological degradation, and what measures can be taken to restore the River's quality? By regionalizing the organization of political jurisdictions, this will allow urban designers and planners to account for externalities and rebuild damaged ecological systems at the geographical scale. Over the past century, man-made interventions have transformed the Mississippi River, altering it from its natural form and processes. These augmentations have been the result of planning decisions, which ignore the larger ecological system of the River. This thesis demonstrates that the existing political juggernaut consists of many actors only considering problems within their own jurisdiction, and therefore make decisions in a vacuum. Instead of making a complete overhaul of the man-made system, this thesis proposes solutions utilizing the existing infrastructure and the waste it produces. It concludes by proposing a new management model: a Sediment Network that redistributes the waste sediment throughout the Mississippi River Basin in the form of new commodities. The Sediment Network illustrates at both the local scale and continental scale, how cities can utilize the sediment as a medium for urban revitalization, restore the River's health, and finally become an instrument for redistributing political power in order to achieve a more holistic form of planning.
by Haley R. Heard.
M.C.P.

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42

Boudreaux, Lon Jr. "The Mississippi River Delta Basin and Why We are Failing to Save its Wetlands." ScholarWorks@UNO, 2007. http://scholarworks.uno.edu/td/564.

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Every thousand years or so, when the Mississippi River's sediment load lengthened and blocked the Riverâ€™s route to the Gulf of Mexico, the mother stream changed course completely, finding a shorter route to the sea. Then, it built a new delta, thus spreading the gift of land creation along a wide coastline and creating the bayou region of Louisiana. However, this ancient, natural process was gradually halted by the arrival of man who settled across the River's natural floodplain (delta) and constructed levees and other structures to control the great Mississippi River. Since the 1930s, the Mississippi River Delta Basin and the coast of Louisiana have been literally losing ground. The decline of this environment is now affecting, and will continue to affect, our nation's economy, infrastructure, culture, and safety. Moreover, efforts to fix this problem are not working. My research and this thesis will address the issue of how plans without action have appeased Louisianans while the nation looses vital wetlands daily.

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43

Teran, Gonzalez Grecia A. "3-D Hydrodynamic and Non-Cohesive Sediment Transport Modeling in the Lower Mississippi River." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1837.

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The purpose of this research is to develop a 3-D numerical model on the Lower Mississippi River to simulate hydrodynamics and non-cohesive sediment transport. The study reach extends from Bonnet Carré Spillway (RM 127) to Head of Passes (RM 0). Delft3D with sigma coordinates was selected as the river modeling tool. This model River domain is characterized by a complex distributary system that connects the Mississippi River to the Gulf of Mexico. The boundary conditions were: water levels in the Gulf and Head of Passes; and discharges upstream. For the calibration, there are observed data for both types of boundary conditions. Several periods of high discharge were simulated to compare water level, discharge, velocity profiles and sediment transport with measurements and accomplish calibration and validation of the model. A calibrated 3-D model has been developed with the following %RMSE: 5% for stage; 6% for discharge; and 5% for sand load.

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Dugger, Katie M. "Foraging ecology and reproductive success of Least terns nesting on the lower Mississippi River /." free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9841279.

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45

Wawrik, Boris. "Diversity and Production of Phytoplankton in the Offshore Mississippi River Plume and Coastal Environments." [Tampa, Fla.] : University of South Florida, 2003. http://purl.fcla.edu/fcla/etd/SFE0000133.

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46

Akalin, Suleyman. "Water temperature effect on sand transport by size fraction in the Lower Mississippi River." Access citation and abstract, 2002. http://wwwlib.umi.com/dissertations/fullcit/3075335.

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47

Hitchcock, Jr Arthur Neil. "Diets of Spring-Migrating Waterfowl in the Upper Mississippi River and Great Lakes Region." OpenSIUC, 2009. https://opensiuc.lib.siu.edu/theses/541.

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I evaluated diet and food selection of 5 species of spring-migrating female waterfowl including 3 dabbling ducks (Blue-winged teal, Anas discors, Mallard, Anas platyrhynchos, Gadwall, Anas strepera) and 2 diving ducks (Lesser Scaup, Aythya affinis, and Ring-necked duck, Aythya collaris). Diet was evaluated with regards to the proportion of invertebrates and seeds consumed, and compared to forage availability data collected in habitats available to them at 6 study locations throughout the Upper Mississippi River and Great Lakes Region. I found latitude (i.e., stage of migration), longitude, food availability, and date all influenced the diet of spring migrating waterfowl, with some factors having a stronger influence than others. I observed differing diet trends with regard to foraging guild (e.g., dabbling and diving ducks), as each foraging guild was represented by 1 species that was heavily dependant on invertebrates (dabbling duck - Blue-winged teal; diving duck - Lesser scaup) and 1 species that was heavily dependant on seeds (dabbling duck - Mallard; diving duck - Ring-necked duck). The proportion of invertebrate foods in the diet increased throughout spring for all species of waterfowl, suggesting the importance of invertebrate food sources during spring staging. Data from this study provides valuable information to habitat managers and conservationists wishing to improve spring habitat conditions for migrating waterfowl, which likely influences waterfowl productivity.

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48

Waterson, Elizabeth J. "Sources of Sedimentary Organic Matter in the Mississippi River and Adjacent Gulf of Mexico." W&M ScholarWorks, 2005. https://scholarworks.wm.edu/etd/1539617828.

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The development of accurate carbon budgets, as well as global climate models with predictive capabilities, requires an understanding of the delivery and fate of terrigenous carbon in the environment. Understanding the extent to which estuarine and continental shelf processes alter carbon transfer between marine and terrestrial systems, including estimates of organic matter accumulation in coastal sediments, is poorly known. Organic carbon and nutrients exported to the adjacent Gulf of Mexico by the Mississippi River are influenced by biological and physical processes including remineralization, hydrodynamic sorting, seabed mixing and bioturbation, and burial. These complex processes make it difficult to know the fate of this organic matter (OM). The objective for this study was to examine the sources and fate of OM along its dispersal pathway from the Mississippi River mouth to the adjacent shelf and canyon. Changes in OM composition (C/N, δ13C, and lipid biomarker compounds) in surface sediment (0-1 cm) were examined along two transects. Using Factor Analysis, biomarkers representing allochthonous (plant) and autochthonous (algal) sources distinguished regional differences between the sites. The river, South West Pass (SW Pass), and marsh sites had greater contributions from higher plant sources. However, sources of OM delivered to these regions differed as evidenced by δ13C stable isotope signatures and C/N ratios. The river sites received inputs from soil organic matter and C3 terrestrial plants while the marsh region received inputs from marsh macrophytes. Despite offshore decreases in biomarkers representing terrigenous sources, signatures of terrigenous OM were present in surface sediments of the distal sites along each transect. The shelf sites had the greatest input of algal material, with biomarkers for diatoms dominating. Down-core analysis of sediment cores collected from three sites (SW Pass, 50 m Proximal, and canyon) further supported the surface sediment results. Plant / terrigenous materials were a major source of OM at the SW Pass site. The box cores from the 50 m Proximal and canyon sites received inputs from both autochthonous and allochthonous sources, with proportionately greater contributions from autochthonous OM. The downcore profiles were influenced by diagenesis as indicated by differences in the ratio of terrestrial to aquatic fatty acids resulting from preferential losses of short-chained fatty acids. This study provides information about sources of OM within the Mississippi River / Gulf of Mexico, and builds upon previous studies in this region. Results from this study illustrate that complex processes influence the fate of terrestrial OM. Hydrodynamic sorting which delivers fine-grained organic rich material further offshore and dilution of terrigenous material by productive shelf sites affect distribution and fate of terrigenous OM. This study also provides baseline information about carbon sources, important for understanding the influence of recent events such as Hurricanes Katrina and Rita, and further management / restoration efforts.

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Harris, Joseph B., T. Andrew Joyner, and Robert V. Rohli. "The Impact of Subsidence on Industrial Complexes in the Lower Mississippi River Industrial Corridor." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/asrf/2018/schedule/40.

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Spatial interpolation methods were analyzed to determine the best fit for subsidence rates and to create a predictive surface for the lower Mississippi River Industrial corridor (LMRIC). Empirical Bayesian kriging, ordinary kriging, universal kriging, and Inverse Distance Weighted interpolation methods were applied to the 2004 National Oceanic and Atmospheric Administration (NOAA) published Technical Report #50 dataset and cross validation methods were utilized to determine the accuracy of each method. The mean error and root mean square error were calculated for each interpolation method, then used to detect bias and compare the predicted value with the actual observation value. Cross-validation estimates are comparable for each method statistically and visually; however, the results indicate the empirical Bayesian kriging interpolation method is the most accurate of the methods using the lowest root mean square scores. Digital elevation models for the years 2025, 2050, and 2075 were developed based on the predictive surface of subsidence rates using the results from the empirical Bayesian kriging interpolation method. Results indicate that by 2025, 30.9% of landmass in the LMRIC will be below sea level, with 41.9% below sea level by 2050, and 53.5% by 2075. Subsidence rates in the LMRIC range from approximately 28 mm to 2 mm per year. Eighteen of the 153 industrial complexes located in the LMRIC are estimated to be below sea level by the year 2075.

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Woock, Celeste E. "Seamless Lidar Surveys Reveal Rates and Patterns of Subsidence in the Mississippi River Delta." ScholarWorks@UNO, 2019. https://scholarworks.uno.edu/td/2656.

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Light Detection and Ranging (Lidar) data are used to report the temporal and spatial patterns of subsidence as well as the potential contributors to subsidence within the Barataria and Terrebonne Bays. In recent decades, subsidence in southeast Louisiana has become a topic of substantial and growing concern to the scientific community, the local residents, and all those invested in the region. Lidar data were acquired from the United States Geological Survey (USGS) and the LSU Center for Geoinformatics. The data has been manipulated to map the differenced Lidar, complete an instantaneous slope analysis, and determine the thickness of the Holocene sediments. The goal was to gain a more comprehensive understanding of the subsidence patterns and the dynamic processes driving subsidence within the study area. These efforts provide a better ability to plan for the future of the Louisiana working coast and mitigate against relative sea level rise and coastal land loss.

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Dissertations / Theses on the topic 'Mississippi (rivier)'

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