scholarly journals The Role of a Permeable Sand Column in Modifying Tidal Creek Nutrient Inputs into the Coastal Ocean

Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3079
Author(s):  
Nicholas A. Legut ◽  
Brandon T. Hawkins ◽  
Angelos K. Hannides
Keyword(s):  
South Carolina ◽  
Nutrient Loading ◽  
Salinity Gradient ◽  
Coastal Ocean ◽  
Coastal Sediments ◽  
Nutrient Inputs ◽  
Tidal Creeks ◽  
Overlying Water ◽  
Sand Column

Estuarine tidal creeks are an important conduit for freshwater run-off into the coastal ocean. In Long Bay, South Carolina, tidal creeks terminate in swashes—broad sandy fields constantly reworked by discharged creek water. We examined the role of a highly permeable sandy column in altering the nutrient loading of the passing water at Singleton Swash, Myrtle Beach, South Carolina. Seasonal transects along the swash’s primary channel documented gradients in physical and biogeochemical parameters. The nutrient and chlorophyll a concentrations were higher in the sediment than in the overlying water, consistent with coastal sediments as a major site of organic matter degradation, nutrient regeneration, and benthic primary productivity. Oxygen, nutrient, and chlorophyll concentrations exhibited a strong seasonal component, explained by a photosynthesis–respiration balance shift between summer and winter. The conservative mixing model approach to elucidate the sink–source patterns was moderately informative due to the lack of a gradual salinity gradient from land to ocean, due to substantial tidal flushing and observable nutrient-rich surface freshwater discharges along the channel that fueled substantial submerged aquatic macroalgal growth. Future studies should focus on the role of benthic photosynthesizers, both microbial and macroalgal, in retaining land-derived nutrients in irrigation freshwater inputs prior to them reaching the coastal ocean.

scholarly journals DOM degradation by light and microbes along the Yukon River-coastal ocean continuum

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Brice K. Grunert ◽  
Maria Tzortziou ◽  
Patrick Neale ◽  
Alana Menendez ◽  
Peter Hernes
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Salinity Gradient ◽  
Coastal Ocean ◽  
Interactive Effects ◽  
The Arctic ◽  
Yukon River ◽  
Spring Freshet ◽  
Dom Composition

AbstractThe Arctic is experiencing rapid warming, resulting in fundamental shifts in hydrologic connectivity and carbon cycling. Dissolved organic matter (DOM) is a significant component of the Arctic and global carbon cycle, and significant perturbations to DOM cycling are expected with Arctic warming. The impact of photochemical and microbial degradation, and their interactive effects, on DOM composition and remineralization have been documented in Arctic soils and rivers. However, the role of microbes, sunlight and their interactions on Arctic DOM alteration and remineralization in the coastal ocean has not been considered, particularly during the spring freshet when DOM loads are high, photoexposure can be quite limited and residence time within river networks is low. Here, we collected DOM samples along a salinity gradient in the Yukon River delta, plume and coastal ocean during peak river discharge immediately after spring freshet and explored the role of UV exposure, microbial transformations and interactive effects on DOM quantity and composition. Our results show: (1) photochemical alteration of DOM significantly shifts processing pathways of terrestrial DOM, including increasing relative humification of DOM by microbes by > 10%; (2) microbes produce humic-like material that is not optically distinguishable from terrestrial humics; and (3) size-fractionation of the microbial community indicates a size-dependent role for DOM remineralization and humification of DOM observed through modeled PARAFAC components of fluorescent DOM, either through direct or community effects. Field observations indicate apparent conservative mixing along the salinity gradient; however, changing photochemical and microbial alteration of DOM with increasing salinity indicate changing DOM composition likely due to microbial activity. Finally, our findings show potential for rapid transformation of DOM in the coastal ocean from photochemical and microbial alteration, with microbes responsible for the majority of dissolved organic matter remineralization.

Emerging Role of Atmospheric Nitrogen Deposition in Coastal Eutrophication: Biogeochemical and Trophic Perspectives

1993 ◽  
Vol 50 (10) ◽  
pp. 2254-2269 ◽  
Author(s):  
Hans W. Paerl
Keyword(s):  
Nutrient Loading ◽  
Western Mediterranean ◽  
Atmospheric Nitrogen ◽  
Nutrient Inputs ◽  
New Production ◽  
Atlantic Seaboard ◽  
Trophic Changes ◽  
The Baltic ◽  
Temporal Interactions

Approximately half of the world's oceanic primary production originates in coastal waters which are often nitrogen (N) limited and sensitive to externally supplied N. Among anthropogenically generated N sources, atmospheric deposition of N (ADN) (as wet- and dryfall) contributes 10–50% of the total external N load at present (20–100 mmol N∙m−2∙yr−1), and this will increase. At current levels, atmospheric N inputs lead to a significant enhancement of CO2 fixation and chlorophyll a production. ADN may play a central role in mediating "new" production in coastal oceans downwind of emissions. Alterations in productivity, nutrient flux, and trophic changes have recently been documented from the Baltic and North seas, the Northwest Atlantic seaboard, and the Western Mediterranean. The recently noted "epidemic" of toxic and nuisance phytoplankton blooms is possibly due to accelerating nutrient loading inshore, especially from atmospheric sources. A need exists to spatially and temporally evaluate, quantify, and potentially manage this nutrient-production interaction on regional and larger synoptic scales. Aircraft- and satellite-based multiband ocean color remote sensing (SeaWiFS) will help characterize and link the spatial-temporal interactions of this (and other) "new" nutrient inputs with biogeochemical and trophic changes in coastal and offshore waters.

scholarly journals Riverine influence on the tropical Atlantic Ocean biogeochemistry

2012 ◽  
Vol 9 (2) ◽  
pp. 1945-1969 ◽  
Author(s):  
L. Cotrim da Cunha ◽  
E. T. Buitenhuis
Keyword(s):  
Atlantic Ocean ◽  
Primary Production ◽  
Coastal Ocean ◽  
South American ◽  
Tropical Atlantic ◽  
Nutrient Inputs ◽  
Export Production ◽  
Tropical Atlantic Ocean ◽  
Ocean Biogeochemistry

Abstract. We assess the role of riverine inputs of N, Si, Fe, organic and inorganic C in the tropical Atlantic Ocean using a global ocean biogeochemistry model. We use two sensitivity tests to investigate the role of the western (South American Rivers) and eastern (African Rivers) riverine nutrient inputs on the tropical Atlantic Ocean biogeochemistry (between 20° S–20° N and 70° W–20°). Increased nutrient availability from river inputs in this area (compared to an extreme scenario with no river nutrients) leads to an increase in 14 % (0.7 Pg C a−1) in open ocean primary production (PP), and 21 % (0.2 Pg C a−1) in coastal ocean PP. We estimate very modest increases in open and coastal ocean export production and sea-air CO2 fluxes. Results suggest that in the tropical Atlantic Ocean, the large riverine nutrient inputs on the western side have a larger impact on primary production and sea-air CO2 exchanges. On the other hand, African river inputs, although smaller than South American inputs, have larger impact on the coastal and open tropical Atlantic Ocean export production. This is probably due to a combination of nutrient trapping in upwelling areas off the Congo River outflow, and differences in delivered nutrient ratios leading to alleviation in limitation conditions mainly for diatoms.

GROUNDWATER EXPORTS OF DOC FROM SALT MARSHES: A SURVEY OF SOUTH CAROLINA TIDAL CREEKS

2019 ◽  
Author(s):  
Alicia Wilson ◽  
◽  
Meghan Shanahan ◽  
Erik M. Smith
Keyword(s):  
South Carolina ◽  
Salt Marshes ◽  
Tidal Creeks

From Need to Policy: Community Supported Development and Implementation of the South Carolina Vulnerable Adult Guardian Ad Litem (SC VAGAL) Program

2020 ◽  
pp. 073346482097880
Author(s):  
M. Aaron Guest ◽  
Brenda Stalzer ◽  
Maria Patton
Keyword(s):  
South Carolina ◽  
Program Development ◽  
Public Service ◽  
Development Process ◽  
Vital Role ◽  
The South ◽  
Pilot Testing ◽  
Abuse And Neglect ◽  
Guardian Ad Litem

Adult guardian ad litem programs are a necessary public service to protect adults from abuse and neglect. This article describes the development and implementation of an adult guardian ad litem program. We discuss the program’s impetus, pilot testing, evaluation, and implementation of the program. Our experience highlights the vital role of diverse inter-sectoral stakeholders. Furthermore, the development process highlights the need for flexibility in program development, tension negotiation among stakeholders, and engagement of aging stakeholders in nontraditional arenas.

scholarly journals A Model Study on the Role of Wetland Zones in Lake Eutrophication and Restoration

2001 ◽  
Vol 1 ◽  
pp. 605-614 ◽  
Author(s):  
J.H. Janse ◽  
W. Ligtvoet ◽  
S. Van Tol ◽  
A.H.M. Bresser
Keyword(s):  
Nutrient Loading ◽  
Predatory Fish ◽  
Nutrient Concentrations ◽  
Fish Stock ◽  
Mixing Rate ◽  
Marsh Vegetation ◽  
Model Calculations ◽  
Critical Loading ◽  
Marsh Area

Shallow lakes respond in different ways to changes in nutrient loading (nitrogen, phosphorus). These lakes may be in two different states: turbid, dominated by phytoplankton, and clear, dominated by submerged macrophytes. Both states are self-stabilizing; a shift from turbid to clear occurs at much lower nutrient loading than a shift in the opposite direction. These critical loading levels vary among lakes and are dependent on morphological, biological, and lake management factors. This paper focuses on the role of wetland zones. Several processes are important: transport and settling of suspended solids, denitrification, nutrient uptake by marsh vegetation (increasing nutrient retention), and improvement of habitat conditions for predatory fish. A conceptual model of a lake with surrounding reed marsh was made, including these relations. The lake-part of this model consists of an existing lake model named PCLake[1]. The relative area of lake and marsh can be varied. Model calculations revealed that nutrient concentrations are lowered by the presence of a marsh area, and that the critical loading level for a shift to clear water is increased. This happens only if the mixing rate of the lake and marsh water is adequate. In general, the relative marsh area should be quite large in order to have a substantial effect. Export of nutrients can be enhanced by harvesting of reed vegetation. Optimal predatory fish stock contributes to water quality improvement, but only if combined with favourable loading and physical conditions. Within limits, the presence of a wetland zone around lakes may thus increase the ability of lakes to cope with nutrients and enhance restoration. Validation of the conclusions in real lakes is recommended, a task hampered by the fact that, in the Netherlands, many wetland zones have disappeared in the past.

scholarly journals Exploring Microbial Resource of Different Rhizocompartments of Dominant Plants Along the Salinity Gradient Around the Hypersaline Lake Ejinur

2021 ◽  
Vol 12 ◽  
Author(s):  
Junqing Luo ◽  
Zhechao Zhang ◽  
Yazhou Hou ◽  
Fengwei Diao ◽  
Baihui Hao ◽  
...  
Keyword(s):  
High Throughput Sequencing ◽  
Salt Lake ◽  
Salinity Gradient ◽  
Salt Lakes ◽  
Hypersaline Environment ◽  
Hypersaline Lake ◽  
Littoral Zones ◽  
Microbial Resources ◽  
Bacteria And Fungi

Lake littoral zones can also be regarded as another extremely hypersaline environment due to hypersaline properties of salt lakes. In this study, high-throughput sequencing technique was used to analyze bacteria and fungi from different rhizocompartments (rhizosphere and endosphere) of four dominant plants along the salinity gradient in the littoral zones of Ejinur Salt Lake. The study found that microbial α-diversity did not increase with the decrease of salinity, indicating that salinity was not the main factor on the effect of microbial diversity. Distance-based redundancy analysis and regression analysis were used to further reveal the relationship between microorganisms from different rhizocompartments and plant species and soil physicochemical properties. Bacteria and fungi in the rhizosphere and endosphere were the most significantly affected by SO42–, SOC, HCO3–, and SOC, respectively. Correlation network analysis revealed the potential role of microorganisms in different root compartments on the regulation of salt stress through synergistic and antagonistic interactions. LEfSe analysis further indicated that dominant microbial taxa in different rhizocompartments had a positive response to plants, such as Marinobacter, Palleronia, Arthrobacter, and Penicillium. This study was of great significance and practical value for understanding salt environments around salt lakes to excavate the potential microbial resources.

The Role of Pierce Butler in the Constitutional Convention

1960 ◽  
Vol 22 (3) ◽  
pp. 361-374 ◽  
Author(s):  
S. Sidney Ulmer
Keyword(s):  
South Carolina ◽  
Constitutional Convention ◽  
Realistic Assessment ◽  
Biographical Sketches ◽  
The Subject ◽  
Fourth Member

It is quite well known that South Carolina sent four aristocrats to represent her in the 1787 Constitutional Convention. It is less well known that one of the four merited a listing in Burke's Peerage. In fact, while much has been written about Charles Pinckney, C. C. Pinckney, and John Rutledge, the fourth member of the delegation has been the subject of a few biographical sketches and virtually nothing more. And yet Pierce Butler was not an insignificant member of the delegation or of the Convention. Indeed, several positive claims to fame that can be established in his behalf suggest the need for a more realistic assessment of his role in the 1787 Convention. This paper is designed as a first step in that direction.

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