scholarly journals Occurrence of Microplastic Pollution at Oyster Reefs and Other Coastal Sites in the Mississippi Sound, USA: Impacts of Freshwater Inflows from Flooding

Toxics ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 35 ◽  
Author(s):  
Austin Scircle ◽  
James V. Cizdziel ◽  
Louis Tisinger ◽  
Tarun Anumol ◽  
Darren Robey
Keyword(s):  
Mississippi River ◽  
Natural Waters ◽  
Gulf Coast ◽  
Size Fraction ◽  
Nile Red ◽  
Dilution Effect ◽  
Relative Distribution ◽  
Oyster Reefs ◽  
Mississippi Sound ◽  
Freshwater Inflows

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.

The Archaic of the Lower Mississippi Valley

1961 ◽  
Vol 26 (3Part1) ◽  
pp. 317-323 ◽  
Author(s):  
William G. Haag
Keyword(s):  
Mississippi River ◽  
Gulf Coast ◽  
General Pattern ◽  
Ohio River ◽  
Mississippi Valley ◽  
Eastern United States ◽  
Alluvial Valley ◽  
Lower Mississippi Valley ◽  
General Acceptance ◽  
Poverty Point

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.

scholarly journals DNA barcoding and metabarcoding of standardized samples reveal patterns of marine benthic diversity

2015 ◽  
Vol 112 (7) ◽  
pp. 2076-2081 ◽  
Author(s):  
Matthieu Leray ◽  
Nancy Knowlton
Keyword(s):  
Large Scale ◽  
Size Fraction ◽  
Taxonomic Composition ◽  
Oyster Reefs ◽  
Ecological Studies ◽  
Marine Life ◽  
Operational Taxonomic Units ◽  
Sequencing Technologies ◽  
Ground Truthing ◽  
Eukaryotic Organisms

Documenting the diversity of marine life is challenging because many species are cryptic, small, and rare, and belong to poorly known groups. New sequencing technologies, especially when combined with standardized sampling, promise to make comprehensive biodiversity assessments and monitoring feasible on a large scale. We used this approach to characterize patterns of diversity on oyster reefs across a range of geographic scales comprising a temperate location [Virginia (VA)] and a subtropical location [Florida (FL)]. Eukaryotic organisms that colonized multilayered settlement surfaces (autonomous reef monitoring structures) over a 6-mo period were identified by cytochrome c oxidase subunit I barcoding (>2-mm mobile organisms) and metabarcoding (sessile and smaller mobile organisms). In a total area of ∼15.64 m2 and volume of ∼0.09 m3, 2,179 operational taxonomic units (OTUs) were recorded from 983,056 sequences. However, only 10.9% could be matched to reference barcodes in public databases, with only 8.2% matching barcodes with both genus and species names. Taxonomic coverage was broad, particularly for animals (22 phyla recorded), but 35.6% of OTUs detected via metabarcoding could not be confidently assigned to a taxonomic group. The smallest size fraction (500 to 106 μm) was the most diverse (more than two-thirds of OTUs). There was little taxonomic overlap between VA and FL, and samples separated by ∼2 m were significantly more similar than samples separated by ∼100 m. Ground-truthing with independent assessments of taxonomic composition indicated that both presence–absence information and relative abundance information are captured by metabarcoding data, suggesting considerable potential for ecological studies and environmental monitoring.

scholarly journals Assessing the Recovery Aftermaths of Selected Disasters in the Gulf of Mexico

2018 ◽  
Vol 9 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Daniel Adrian Doss ◽  
David Mcelreath ◽  
Rebecca Goza ◽  
Raymond Tesiero ◽  
Balakrishna Gokaraju ◽  
...  
Keyword(s):  
Gulf Of Mexico ◽  
Natural Disasters ◽  
Hurricane Katrina ◽  
Oil Spill ◽  
Mississippi River ◽  
Gulf Coast ◽  
British Petroleum ◽  
River Flood ◽  
British Petroleum Oil Spill ◽  
Petroleum Oil

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.

scholarly journals The Muscadine Grape (Vitis rotundifolia Michx)

EDIS ◽  
2020 ◽  
Vol 2020 (6) ◽  
Author(s):  
Peter C. Andersen ◽  
Ali Sarkhosh ◽  
Dustin Huff ◽  
Jacque Breman
Keyword(s):  
Mississippi River ◽  
Skin Color ◽  
Gulf Coast ◽  
Calcareous Soils ◽  
Vitis Vinifera L ◽  
Vitis Rotundifolia ◽  
Grape Berries ◽  
In The Wild ◽  
Muscadine Grape ◽  
Muscadine Grapes

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.

A Tale of Three Lineages: Expansion of Common Reed (Phragmites australis) in the U.S. Southwest and Gulf Coast

2010 ◽  
Vol 3 (4) ◽  
pp. 515-520 ◽  
Author(s):  
Laura A. Meyerson ◽  
Adam M. Lambert ◽  
Kristin Saltonstall
Keyword(s):  
Mississippi River ◽  
Native Species ◽  
Gulf Coast ◽  
Unknown Origin ◽  
Common Reed ◽  
Dominant Form ◽  
Native North American ◽  
Eurasian Lineage ◽  
The Common ◽  
The U.S

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.

scholarly journals Oyster growth across a salinity gradient in a shallow, subtropical Gulf of Mexico estuary

2021 ◽  
Vol 2 ◽  
Author(s):  
Benoit Lebreton ◽  
Jennifer Beseres Pollack ◽  
Brittany Blomberg ◽  
Terence A. Palmer ◽  
Paul A. Montagna
Keyword(s):  
Soft Tissues ◽  
Salinity Gradient ◽  
Oyster Shell ◽  
Past Century ◽  
Oyster Reefs ◽  
Oyster Aquaculture ◽  
Subtropical Estuary ◽  
Oyster Farms ◽  
Freshwater Inflows ◽  
River Mouths

Abstract An increase in oyster aquaculture as a sustainable method of shellfish production is one response to overharvest and degradation of natural oyster reefs over the past century. Successful aquaculture production requires determining the environmental conditions optimal for oyster growth. In this study, the salinity, temperature, chlorophyll a concentration and the growth of Crassostrea virginica were monitored at four locations within the Mission-Aransas Estuary, Texas (USA), a shallow subtropical estuary influenced by relatively low freshwater inflow. Mean growth of the oyster shell (0.205 mm d–1 and 0.203 g d–1) and soft tissues (3.447 mg d–1) was highest when salinity was low (mean = 15.5) and chlorophyll a concentration was high (8.4 μg l–1). Oyster growth also varied temporally with periods of spawning. In low-inflow estuaries such as the Mission-Aransas Estuary, oyster farms should be sited close to river mouths so that oysters can benefit from freshwater inflows and lower salinities.

scholarly journals Long Distance Implantation of Vernacular Architecture Traditions: The Canadians in Early Louisiana

2020 ◽  
Vol 88-89 ◽  
pp. 45-78
Author(s):  
Jay D. Edwards
Keyword(s):  
Relative Abundance ◽  
Mississippi River ◽  
18Th Century ◽  
Gulf Coast ◽  
Architectural History ◽  
Vernacular Architecture ◽  
Long Distance ◽  
Lower Mississippi River ◽  
Mississippi Gulf Coast ◽  
First Time

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.

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