Christopher D'Elia

Louisiana State University | LSU · College of the Coast and Environment

Low elevation coastal zones (LECZ) are extensive throughout the southeastern United States. LECZ communities are threatened by inundation from sea level rise, storm surge, wetland degradation, land subsidence, and hydrological flooding. Communication among scientists, stakeholders, policy makers and minority and poor residents must improve. We must...

Floods are among the most common natural hazards with complex and far-reaching impacts. Coastal floods are most often caused by storm surge (coastal), rivers that exceed their flood stage capacity (fluvial), and torrential rainfall (pluvial). Increasingly, compound flooding by all three causes is the most severe. The adverse consequences of flood e...

Coastal Louisiana owes its existence entirely to sediments supplied to the Gulf of Mexico coast by the Mississippi River. Today, land loss greatly exceeds land creation. The extensive engineering works that were intended to protect people and assets from floods and support navigability of the lower Mississippi River are now profoundly implicated in...

The Mid-Atlantic Bight (MAB) extends alongshore, from Cape Cod, MA to Cape Hatteras, NC and includes major estuarine systems such as Narragansett Bay, Long Island Sound, Chesapeake Bay and Pamlico Sound. Sea level rise continues to have a dramatic effect on developed watersheds and urban estuaries, which are common to this highly populated region....

Flood control levees cut off the supply of sediment to Mississippi delta coastal wetlands, and contribute to putting much of the delta on a trajectory for continued submergence in the 21st century. River sediment diversions have been proposed as a method to provide a sustainable supply of sediment to the delta, but the frequency and magnitude of th...

To meet the COP21 2 °C climate target, humanity would need to complete a transition to renewable energy within the next several decades. But for decades, fossil fuels will continue to underpin many fundamental activities that allow modern society to function. Unfortunately, net energy yield from fossil fuels is now falling, and despite substantial...

Currently the Mississippi delta stands as a highly degraded and threatened coastal ecosystem having lost about 25% of coastal wetlands during the twentieth century. To address this problem, a $50 billion, 50 year restoration program is underway. A central component of this program is reintroduction of river water back into the deltaic plain to mimi...

Over 25% of Mississippi River delta plain (MRDP) wetlands were lost over the past century. There is currently a major effort to restore the MRDP focused on a 50-year time horizon, a period during which the energy system and climate will change dramatically. We used a calibrated MRDP marsh elevation model to assess the costs of hydraulic dredging to...

Integrating models from the social and natural sciences could generate a more holistic approach to climate change response planning in coastal communities.

The Land-Ocean Interactions in the Coastal Zone (LOICZ) project was established in 1993 as a core project of the International Geosphere-Biosphere Programme (IGBP) to provide the science knowledge to answer “How will changes in land use, sea level and climate alter coastal systems, and what are the wider consequences?” In its first phase of operati...

An interdisciplinary, collaborative program is needed to facilitate predictions of the inter-connected factors that will impact coastal systems and the resilience of coastal communities over the next few decades. Two interdisciplinary workshops were held, in 2014 and 2015, to develop consensus as to the needs and scope that might be included in suc...

This book takes you on a unique journey through American history, taking time to consider the forces that shaped the development of various cities and regions, and arrives at an unexpected conclusion regarding sustainability. From the American Dream to globalization to the digital and information revolutions, we assume that humans have taken contro...

The mutualistic relationship between corals and their dinoflagellate endosymbionts is a key factor in the evolutionary success of hermatypic (reef building) corals. The endosymbiotic algae benefit corals in numerous ways that have contributed to the long term persistence of coral reefs over geologic time. In this chapter we review ecological and ph...

The response to the Deepwater Horizon Disaster, the worst oil spill in maritime history, focused on determining the fate and the marine biological effects of the oil spill with little effort on assessing the emotional well-being of people directly harmed by the spill. The mental anguish experienced by the people, many who were still recovering from...

Informal place-based environmental education is a proven approach for increasing environmental awareness for students in urban cities. This article describes and qualitatively evaluates the first two academic years of the EnvironMentors program at Louisiana State University (LSU-EM), which is part of a national network of EnvironMentors programs. D...

Sustainability of natural resources requires balancing exploitation and conservation, enabled by management based on the best available scientific and economic information. Valuation of ecosystemgoods and services is an important tool for prioritizing restoration efforts, recognizing the economic importance of conserving natural capital, and raisin...

Natural phytoplankton assemblages from the Patuxent River estuary were maintained in outdoor, large-volume, continuous cultures and subjected to nutrient enrichment in a series of experiments over an 18-mo period. Nitrogen (either ammonium or nitrate) enrichment during summer and fall produced large changes in dominant species and patterns of speci...

The response of phytoplanktonic growth to experimental nutrient addition in a tributary of the Chesapeake Bay estuary varied with season and nutrient availability. In bioassay experiments employing outdoor 0.5-m3 continuous cultures freshly inoculated with natural phytoplankton from the Patuxent River estuary, supplements of N, either as ammonium o...

The most comprehensive study of a coral reef undertaken until that time, the Symbios Expedition, was conducted in 1971 by an interdisciplinary team of ecologists and oceanographers. The study site was at Enewetak Atoll, Marshall Islands, and the R/V Alpha Helix along with shore-based facilities provided laboratory and logistical support. Many coral...

Recently published models, which allow for spatial and temporal matching of oyster and phytoplankton populations in mainstream Chesapeake Bay, support the conclusion of Pomeroy et al. (2006; Mar Ecol Prog Ser 325:301-309) that oysters cannot, and could not, control the spring blooms that are the ultimate cause of summer hypoxia. We enlarge upon our...

Restoration of the oyster Crassostrea virginica population in Chesapeake Bay is often advocated as an easy solution for controlling phytoplankton blooms. Even at their pre-colonial densities, oysters are unlikely to have controlled blooms, despite the fact that sediment cores suggest that pre-colonial spring blooms were smaller than at present. Lac...

The recent Editorial “The high cost of coming to America” by A. Teich and W. D. White (5 May, p. [657][1]) calls attention to the humiliating and unjustifiable treatment of distinguished scientists such as Goverdhan Mehta in the Visas Mantis program. The Visas Mantis program is just the tip of

Similar NH4+ and NO3−.uptake kinetic patterns were observed in Neoagardhiella baileyi (Harvey ex Kiitzing) Wyinne & Taylor and Gracilaria foliifera (Forssk?l) Borgesen. NO3− was taken up in a rate-sturating fashion described by the Michaelis-Menten equation. NH4+ uptake was multicomponent: a saturable component was accompanied by a diffusive or a h...

The Patuxent River, Maryland, is a nutrient-overenriched tributary of the Chesapeake Bay. Nutrient inputs from sewage outfalls and nonpoint sources (NPS) have grown substantially during the last four decades, and chlorophylla levels have increased markedly with concomitant reductions in water quality and dissolved oxygen concentrations. The Patuxen...

This report to the federal-state Interagency Working Group on Florida Bay was prepared by a panel of scientists invited by the Assistant Secretary of the Department of the Interior to provide an objective analysis of the deterioration in the Florida Bay ecosystem to help guide management and research priorities. Florida Bay has undergone changes du...

1999. The Academic Research Fleet: A Report to the Assistant Director for Geosciences by the Fleet Review Committee. National Science Foundation, Washington, DC.

Citation: C.F. D’Elia. 1995. Sustainable development and the Chesapeake Bay: A case study, pp. 161-176. In: Mohan Munasinghe and Walter Shearer [eds.], Defining and Measuring Sustainability: The Biophysical Foundations. The United Nations University and The World Bank, Washington, D.C.

The elemental composition (C, N, and P) of zooxanthellae and host tissue from the coral Pocillopora damicornis (Linnaeus) was determined after maintenance in flowing seawater with 20-uM and 50-M ammonium enrichments for periods of 2 to 8 weeks. Compared with ambient seawater controls, total zooxanthellar nitrogen (ug N cm-2 colony surface) increase...

The results of a workshop conducted by scientists who participated in a 6-year, multidisciplinary study of hypoxia on the Chesapeake Bay suggest that although an exact quantification of the management target for nutrient reduction is difficult to make, at least a 40% reduction in total inputs is needed to reduce hypoxia and restore a trophic struct...

The nutrient status of algae symbiotic with marine invertebrates is controversial. We assessed the nitrogen status of zooxanthellae symbiotic with the sea anemone Aiptasia pallida using NH,+ enhancement of dark C fixation; enhancement increases with N limitation in other microalgae. Freshly isolated symbionts obtained from laboratory populations of...

This paper draws heavily from experiences with an extensive monitoring program for the Chesapeake Bay that provides a wide range of examples to illustrate problems inevitably encountered in other monitoring programs. It draws attention to deficiencies in the conceptual basis of monitoring nationally and scrutinizes methods to improve standard metho...

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The response of natural estuarine phytoplankton communities to nutrient enrichment was investigated using large-volume outdoor continuous cultures. The five-year study in the Patuxent River, MD, revealed a strong enrichment potential for nitrogen (N) during summer/fall, often resulting in tenfold increases in biomass within 48 hr. Largely due to in...

Cnidarians with endosymbiotic algae (=zooxanthellae) take up dissolved inorganic nutrients from seawater, but neither the physiological mechanisms nor the effect of host nutrition on transport kinetics is known. We used the NH 4 ⁺ analogue [ ¹⁴ C]methylamine ([ ¹⁴ C]MA) to examine these aspects of NH 4 ⁺ uptake by a sea anemone ( Aiptasia pallida )...

Nutrient sufficiency of zooxanthellae in the sea anemone Aiptasia pallida cultured in low nutrient seawater depends on the availability of particulate food to the host. Zooxanthellae in anemones unfed for 20 to 30 d exhibited the following characteristics of nutrient deficiency: cell division rates decreased; chlorophyll a content gradually decreas...

Indicates general features of coral reef productivity, drawing comparison with other shallow water marine systems, and reviews the major sources and sinks of nutrients. Reef structure and water residence time affect nutrient availability, as do net evaporation and precipitation. A critique is provided of different approaches to understanding nutrie...

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Natural phytoplankton assemblages from the Patuxent River estuary were maintained in outdoor, large-volume, continuous cultures and subjected to nutrient enrichment. Nitrogen enrichment during summer and fall produced large changes in dominant species and patterns of species successions, yielding an assemblage much different from unenriched control...

Water quality monitoring studies typically include chemical parameters such as nutrients. Detection limits, precision and accuracy in the chemical analysis of these parameters can have a major impact upon data analysis and tests of hypotheses posed by monitoring studies. The analytical techniques used to measure these chemical parameters, however o...

Growth characteristics and nutrient uptake kinetics were determined for zooxanthellae (Gymnodinium microadriaticum) in laboratory culture. The maximum specific growth rate (max) was 0.35 d-1 at 27 C, 12 hL:12 hD cycle, 45 E m-2 s-1. Anmmonium and nitrate uptake by G. microadriaticum in distinct growth phases exhibited Michaelis-Menten kinetics. Amm...

Silicic acid (H4SiO4) flux from the sediment, H4SiO4 concentration and river flow were used to obtain an annual dissolved silicon budget for Chesapeake Bay. H4SiO4 concentrations vary seasonally in the estuary: for a 12-year period, mean H4SiO4 concentrations in the mesohaline region were high both in spring and in late summer to early fall, and we...

Zooxanthellae of the species Gymnodinium (=Symbiodinium) microadriaticum freshly isolated from a variety of hosts (Zoanthus spp., Tridacna crocea, Seriatopora hystrix, Montastrea annularis, Porites furcata, and Stylophora pistillata) in the tropical Pacific Ocean and the Caribbean Sea exhibited saturation uptake kinetics when incubated in seawater...

In a study of reef zonation and diversity of Cayos Arcas, the most southerly reef, the coral reefs surrounding three sand cays were found to exhibit a greater diversity of scleractinian coral species than has been reported previously for the Campeche Bank region. Hermatypic coral coverage was high and coral growth appeared vigorous. Zonation and th...

The role of physical interfaces in estuarine nitrogen (N) dynamics is discussed. We consider here: four N-transformation processes (uptake, regeneration, de nitrification, nitrification) and five interfaces (water mass fronts and transitions, watershed-estuarine boundaries, the pycnocline of stratified estuaries, the sediment-water boundary, the re...

Species-specific photosynthetic responses to stress were detected in mixed phytoplankton assemblages using autoradiography. In laboratory experiments subjecting a mixture of the diatom Phaeodactylum and the flagellate Pseudoisochrysis to control and transient thermal stress treatments of +5, +10, +15 and +20°C, both species responded negatively wit...

The freshwater aquifer at Discovery Bay, Jamaica, produces subterranean springs and seeps near the reef at the mouth and along the southern and western shorelines of the bay. A strong inverse correlation exists between salinity and N concentration. Undiluted spring-water typically contains 80 μg at N per liter or more, primarily as nitrate, but is...

In situ measurements of inorganic nitrogen fluxes and riverbed oxygen consumption were made on sediments in 3, 9, and 16 m of water at the mouth of the York River during stratified and destratified water conditions. Ammonia was regenerated, the rate of which increased with depth and oxygen concentration in the overlying water. Nitrate and nitrite f...

This paper is included in this symposium volume to illustrate the effect hydrographic factors such as the spring-neap tidal stratification-destratification cycle (4) can have on the distribution of oxygen and nutrients in the water column of an estuary. All too often scientists, modelers and managers, finding hydrographic processes in estuaries ext...

Spring tidal currents produce homogeneous water columns in a number of estuaries that are moderately stratified during neap tides. In the York River estuary, this destratification redistributes ammonium and phosphate regenerated by the benthos as well as oxygen from the surface. This redistribution has significant implications for nutrient cycles,...

The marine diatoms Phaeodactylum tricornutum (Bohlin) and Thalassiosira pseudonana (Hasle and Heimdal) were grown under both continous illumination and a 14 h light: 10 h dark cycle at light intensities ranging from 1.5310-4 to 2.9510-1 ly min-1. Under both photoperiods, T. pseudonana exhibited higher division rates than P. tricornutum at high ligh...

Two marine diatoms, Phaeodactylum tricornutum (Bohlin) and Thalassiosira pseudonana (Hasle and Heimdal), were grown both separately and together in batch cultures on a mixture of waste water and seawater enriched with different components of f medium. At 17C, the maximum division rates of the two species were statistically indistinguishable. The wa...

Gracilaria foliifera (Forsskal) Borgesen and Neoagardhiella bailiyi (Harvey ex Kiitzing) Wynne & Taylor were grown in continuous-flow culture under controlled environmental conditions in 15 liter experimental chambers. Growth rate was related to the source and concentration of nitrogen enrichment supplied to the plants, Growth rate appeared to foll...

Abstract Of several genera tested, only those Pacific reef corals symbiotic with zooxanthellae take up and retain ammonium. Uptake and retention are enhanced by light, and the normal day- light period,is sufficient,to sustain,ammonium,retention,during,the night. Ammonium,uptake kinetics,for several,species,indicate,that a two-process,mechanism,may,...

The endocytic mechanisms of the digestive cells of Hydra viridis were examined by transmission electron microscopy. Algae which form a stable intracellular symbiosis are phagocytosed by uncoated plasmalemma, as are large (greater than 0.5 micron) food particles. Discoidal coated vesicles apparently effect the endocytosis of smaller particles, inclu...

Biomass production and nitrogen balance was studied in 35,000 gal (133,000 1) phytoplankton cultures comprising the first stage in a tertiary sewage treatment-mariculture system. The diatom Phaeodactylum tricornutum persisted for most of the study. At secondary sewage effluent loadings sufficient to produce residual dissolved inorganic nitrogen con...

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The fluxes of dissolved reactive, organic, and total phosphorus into and out of non‐feeding corals were measured by chemical and radiochemical techniques. A net uptake of reactive phosphorus from seawater by corals containing zooxanthellae was not, at typical ambient phosphorus levels, sufficient to offset simultaneous losses of organic P. Conseque...

There were four primary goals of our project. The first was to compare two standard primary productivity measurement techniques (14C and 02) that have been used in the past at the Calvert Cliffs Nuclear Power Plant (CCNPP) to determine whether measurements made by one technique are directly comparable to those made by the other. Several light level...

Thesis--University of Georgia, 1974.