MISSISSIPPI RIVER AND GULF COAST TERRACES AND SEDIMENTS AS RELATED TO PLEISTOCENE HISTORY—A PROBLEM

Author(s):  
A. C. TROWBRIDGE
Keyword(s):  
Toxics ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 35 ◽  
Author(s):  
Austin Scircle ◽  
James V. Cizdziel ◽  
Louis Tisinger ◽  
Tarun Anumol ◽  
Darren Robey

Much of the seafood that humans consume comes from estuaries and coastal areas where microplastics (MPs) accumulate, due in part to continual input and degradation of plastic litter from rivers and runoff. As filter feeders, oysters (Crassostrea virginica) are especially vulnerable to MP pollution. In this study, we assessed MP pollution in water at oyster reefs along the Mississippi Gulf Coast when: (1) historic flooding of the Mississippi River caused the Bonnet Carré Spillway to remain open for a record period of time causing major freshwater intrusion to the area and deleterious impacts on the species and (2) the spillway was closed, and normal salinity conditions resumed. Microplastics (~25 µm–5 mm) were isolated using a single-pot method, preparing samples in the same vessel (Mason jars) used for their collection right up until the MPs were transferred onto filters for analyses. The MPs were quantified using Nile Red fluorescence detection and identified using laser direct infrared (LDIR) analysis. Concentrations ranged from ~12 to 381 particles/L and tended to decrease at sites impacted by major freshwater intrusion. With the spillway open, average MP concentrations were positively correlated with salinity (r = 0.87, p = 0.05) for sites with three or more samples examined. However, the dilution effect on MP abundances was temporary, and oyster yields suffered from the extended periods of lower salinity. There were no significant changes in the relative distribution of MPs during freshwater intrusions; most of the MPs (>50%) were in the lower size fraction (~25–90 µm) and consisted mostly of fragments (~84%), followed by fibers (~11%) and beads (~5%). The most prevalent plastic was polyester, followed by acrylates/polyurethanes, polyamide, polypropylene, polyethylene, and polyacetal. Overall, this work provides much-needed empirical data on the abundances, morphologies, and types of MPs that oysters are exposed to in the Mississippi Sound, although how much of these MPs are ingested and their impacts on the organisms deserves further scrutiny. This paper is believed to be the first major application of LDIR to the analysis of MPs in natural waters.


1961 ◽  
Vol 26 (3Part1) ◽  
pp. 317-323 ◽  
Author(s):  
William G. Haag

AbstractNo archaeological remains which the majority of specialists will accept as Archaic have been found in the Mississippi Valley from the mouth of Ohio River to the Gulf of Mexico. Despite this, the literature reflects a general acceptance of the belief that the Archaic stage is well represented in the Lower Valley. The presence of concentrated Archaic populations in northern Alabama and western Tennessee and Kentucky has given comparative support to these expectations and has provided part of the source for some of the hypothetical statements in the literature of what the Lower Valley Archaic ought to be like. Although the failure of writers to agree on a definition of Archaic which will satisfy the evidence in all of the areas of Eastern United States has contributed to the problem of identifying Archaic materials in the Lower Valley, the lack of these remains can best be explained by the geology of the region. The cutting and filling of the Alluvial Valley during the Pleistocene changes in sea level have removed or buried all of the surfaces that might have been occupied by Archaic peoples. The surface of the Alluvial Valley is everywhere less than 5000 years old. Possible Late Archaic sites are located on old stable beach ridges or near enough to the Pleistocene terraces not to have been included in the general pattern of Recent coastal subsidence. It is concluded that Archaic or earlier materials are absent in the Lower Alluvial Valley of the Mississippi River. Neither Tchefuncte nor Copell are accepted as Archaic; Poverty Point is viewed as transitional from an Upper Archaic tradition to some phase of the Formative stage. Poverty Point materials may not be expected to be found in quantity along the Gulf Coast of the Mississippi Delta region.


2018 ◽  
Vol 9 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Daniel Adrian Doss ◽  
David Mcelreath ◽  
Rebecca Goza ◽  
Raymond Tesiero ◽  
Balakrishna Gokaraju ◽  
...  

AbstractThis research examined quantitatively in-port grain loading levels during the periods preceding and succeeding selected human-made and natural disasters among U.S. Gulf Coast ports. The array of selected disasters consisted of the 2010 British Petroleum oil spill, the 2011 Mississippi River flood, Hurricane Katrina, Hurricane Gustav, and Hurricane Isaac. The outcomes of the analyses showed that the examined in-port Gulf Coast grain loading activities have not fully recovered and achieved the level of normalcy that existed before the examined cataclysms.


EDIS ◽  
2020 ◽  
Vol 2020 (6) ◽  
Author(s):  
Peter C. Andersen ◽  
Ali Sarkhosh ◽  
Dustin Huff ◽  
Jacque Breman

The muscadine grape is native to the southeastern United States and was the first native grape species to be cultivated in North America. The natural range of muscadine grapes extends from Delaware to central Florida and occurs in all states along the Gulf Coast to east Texas. It also extends northward along the Mississippi River to Missouri. Muscadine grapes will perform well throughout Florida, although performance is poor in calcareous soils or in soils with very poor drainage. Most scientists divide the Vitis genus into two subgenera: Euvitis (the European, Vitis vinifera L. grapes and the American bunch grapes, Vitis labrusca L.) and the Muscadania grapes (muscadine grapes). There are three species within the Muscadania subgenera (Vitis munsoniana, Vitis popenoei and Vitis rotundifolia). Euvitis and Muscadania have somatic chromosome numbers of 38 and 40, respectively. Vines do best in deep, fertile soils, and they can often be found in beside river beds.  Wild muscadine grapes are functionally dioecious due to incomplete stamen formation in female vines and incomplete pistil formation in male vines. Male vines account for the majority of the wild muscadine grape population. Muscadine grapes are late in breaking bud in the spring and require 100-120 days to mature fruit. Typically, muscadine grapes in the wild bear dark fruit with usually 4 to 10 fruit per cluster. Bronze-fruited muscadine grapes are also found in the wild, and they are often referred to as scuppernongs. There are hundreds of named muscadine grape cultivars from improved selections, and in fact, one that has been found in the Scuppernong river of North Carolina has been named Scuppernong. There are over 100 improved cultivars of muscadine grapes that vary in size from 1/4 to 1 ½ inches in diameter and 4 to 15 grams in weight. Skin color ranges from light bronze to pink to purple to black. Flesh is clear and translucent for all muscadine grape berries. Originally published 1994 by Peter C. Anderson and Timothy E. Crocker. Published on EDIS June 2003. Revised November 2010, October 2013, January 2017. This revision with Sarkhosh and Huff.


2010 ◽  
Vol 3 (4) ◽  
pp. 515-520 ◽  
Author(s):  
Laura A. Meyerson ◽  
Adam M. Lambert ◽  
Kristin Saltonstall

AbstractThe common reed invasion in North America has spanned two centuries and is still ongoing. This expansion comprises two main forms: an introduced Eurasian lineage (identified here as “Introduced Phragmites”) and a Gulf Coast lineage of unknown origin (identified here as “Gulf Coast Phragmites”). Both lineages are spreading beyond their current ranges and are colonizing Southwestern and Gulf Coast ecosystems where they have not previously existed. As a result, the native North American lineage of common reed (hereafter “native Phragmites”) has declined in many places. The recent invasion of the U.S. Southwest by Introduced and Gulf Coast Phragmites lineages has made this the only region in the world colonized by all three lineages. Along the central Gulf Coast where Gulf Coast Phragmites remains the dominant form, Introduced Phragmites has also recently invaded the Mississippi River delta. The consequences of these new invasions are uncertain, but a rapid response is needed to protect native species and ecosystems and reduce future control costs.


2020 ◽  
Vol 88-89 ◽  
pp. 45-78
Author(s):  
Jay D. Edwards

This study explores the architectural contributions of Canadians to Louisiana in the 18th century. One of the most revealing arenas in American architectural history concerns the origins of new vernacular traditions in locations being settled for the first time by Europeans. Between the late 15th and 18th centuries, many settlement experiments occurred along the coastlines of the Atlantic. Yet the dearth of reliable documentation from the earliest years of colonial establishment renders elusive a sound understanding of the factors which shaped these foundational architectural transformations. The result: a loss of understanding of the very essence of our American vernacular traditions. This study examines one such case for which a relative abundance of documentation survives—the Canadians in Louisiana. It traces the architectural transformations that materialized when Canadians attempted to found a new colony on the Mississippi Gulf Coast and the lower Mississippi River Valley, beginning in 1699.


2012 ◽  
Vol 46 (2) ◽  
pp. 461-480 ◽  
Author(s):  
DOLLY JØRGENSEN

On 26 June 2010, the brand new Gulf of Mexico exhibit at the National Mississippi River Museum & Aquarium in Dubuque, Iowa opened devoid of life. The tanks were purposefully left empty, rather than showing the vibrant aquatic life of the Gulf, to highlight the oil spill associated with BP's Deepwater Horizon offshore drilling incident earlier in 2010. According to the museum's press release, the museum wantedto open a Gulf exhibit recognizing the crisis that is happening on the Gulf Coast … The exhibit, without fish, now has the opportunity to make a bold statement related to the oil spill in the Gulf Coast by asking Museum & Aquarium visitors to imagine a lifeless Gulf.1


Zootaxa ◽  
2008 ◽  
Vol 1680 (1) ◽  
pp. 62 ◽  
Author(s):  
STUART A. WELSH ◽  
ROBERT M. WOOD

A new species of percid, Crystallaria cincotta, is described from the Cumberland, Elk, Green, and Muskingum river drainages of the Ohio River basin, USA. It differs from populations of Crystallaria asprella of the Gulf Coast, lower Mississippi River, middle Mississippi River, upper Mississippi River, and Wabash River drainages by having a reduced number of cheek scale rows restricted to the post-orbital region, a falcate margin on the pelvic fins, a preorbital blotch distinctly separate from the anterior orbital rim, and a wide mouth gape. The Elk River population is also divergent genetically from populations of the Gulf Coast, lower Mississippi River, and upper Mississippi River drainages. Crystallaria cincotta, discovered in the Elk River of the Ohio River drainage in 1980, is a rare species with the only extant population represented by 12 individuals collected from 1980–2005 from the lower 36 km section of the Elk River, West Virginia.


Author(s):  
M. Ghose-Hajra ◽  
A. McCorquodale ◽  
G. Mattson ◽  
D. Jerolleman ◽  
J. Filostrat

Abstract. Sea-level rise, the increasing number and intensity of storms, oil and groundwater extraction, and coastal land subsidence are putting people and property at risk along Louisiana’s coast, with major implications for human safety and economic health of coastal areas. A major goal towards re-establishing a healthy and sustainable coastal ecosystem has been to rebuild Louisiana’s disappearing wetlands with fine grained sediments that are dredged or diverted from nearby rivers, channels and lakes to build land in open water areas. A thorough geo-hydrodynamic characterization of the deposited sediments is important in the correct design and a more realistic outcome assessment of the long-term performance measures for ongoing coastal restoration projects. This paper evaluates the effects of salinity and solid particle concentration on the re-suspension characteristics of fine-grained dredged sediments obtained from multiple geographic locations along the Gulf coast. The critical bed-shear-stress for erosion has been evaluated as a function of sedimentation time. The sediment hydrodynamic properties obtained from the laboratory testing were used in a numerical coastal sediment distribution model to aid in evaluating sediment diversions from the Mississippi River into Breton Sound and Barataria Bay.


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