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Ii. Curriculum Models That Include Undergraduate Research

Innovations in Undergraduate Research and Honors Education: Proceedings of the Second Schreyer National Conference 2001

This chapter features different perspectives on integrating research into the curriculum. The series of papers describes programs, credit bearing as well as non-credit bearing, that include a significant research component.

The first four papers provide an excellent contrast of approaches to bringing research into the undergraduate curriculum. The Gemstone Program at the University of Maryland is a fouryear honors program that includes research methods courses and a four-year-long, team-based research project. The students identify the topic, propose the research question and are mentored by a faculty member. The next model describes the efforts in Muhlenberg College's Biology Department to include …

Limited Attention: The Constraint Underlying Search Image, Reuven Dukas, Alan Kamil

Papers in Behavior in Biological Sciences

Recent models of predator search behavior integrate proximate neurobiological constraints with ultimate economic considerations. These models are based on two assumptions, which we have critically examined in experiments with blue jays searching for artificial prey images presented on a computer monitor. We found, first, that when jays had to switch between searching for two distinct prey types, they showed no reduction in detection rates compared to no-switching to no-switching conditions, and second, that when jays divided attention between searching for two prey types at the same time, they had lower detection rates than when they focused attention on one prey …

Manure Matters, Volume 7, Number 1, J. P. Harner, T. D. Strahm, D. Key, T. L. Strahm, J.P. Murphy

Manure Matters (newsletter)

Time and motion (TM) studies are useful in determining labor requirement to perform a specific task in manufacturing processes. These studies have been used in the dairy industry to evaluate the labor requirements for various tasks associated with milking routine and milk parlor. Data may be used to evaluate the impact of changes or help in understanding labor requirements. The objective of this project was to determine the labor requirements for removing manure from concrete basins prior to land applications.

A Revision Of Parhyalella Kunkel (Crustacea: Amphipoda: Gammaridea), Eric A. Lazo-Wasem, Michael F. Gable

Bulletin of the Peabody Museum of Natural History

The genus Parhyalella Kunkel, sensu lato, is revised, based on a review of type material for all previously described species, and on new material….

On The Insensitivity Of The Wind-Driven Circulation To Bottom Topography, David P. Marshall, James C. Stephens

Journal of Marine Research

An analytical model is developed for the wind-driven circulation in a continuously stratified ocean overlying variable bottom topography. In the ocean interior we adopt a linear relation between potential vorticity, density and Montgomery potential, resulting in Welander's solution for an adiabatic internal thermocline. The horizontal structure of the circulation is described by a characteristic equation, obtained by imposing a boundary condition of no-normal flow at the sea floor and a prescribed vertical velocity through the base of the surface Ekman layer. The characteristics, which determine the extent to which bottom topography "steers" the circulation within the upper ocean, are dominated …

Absorbed Mn2+ And Mn Redox Cycling In Iberian Continental Margin Sediments (Northeast Atlantic Ocean), Claar Van Der Zee, Wim Van Raaphorst, Eric Epping

Journal of Marine Research

Although Mn²⁺ sorption has been investigated extensively in the laboratory, the role of Mn²⁺ sorption in natural marine sediments remains speculative. Our objectives were to study (1) the role of Mn²⁺ sorption in the redox cycling of Mn, (2) to quantify Mn cycling and (3) to identify its rate-determining factors at the Iberian margin. Profiles of pore water Mn²⁺, adsorbed Mn²⁺ and solid phase Mn were measured together with benthic oxygen fluxes along three transects across the margin from the shelf to the deep sea as well as in the Nazeré Canyon. In the …

Annual To Interannual Variations Of Ƒco2 In The Northwestern Mediterranean Sea: Results From Hourly Measurements Made By Carioca Buoys, 1995–1997, E. M. Hood, L. Merlivat

Journal of Marine Research

A time series of fCO₂, SST, and fluorescence data was collected between 1995 and 1997 by a CARIOCA buoy moored at the DyFAMed station (Dynamique des Flux Atmospheriques en Mediterranée) located in the northwestern Mediterranean Sea. On seasonal timescales, the spring phytoplankton bloom decreases the surface water fCO₂ to approximately 290 µatm, followed by summer heating and a strong increase in fCO₂ to a maximum of approximately 510 µatm. While the ΔfCO₂ shows strong variations on seasonal timescales, the annual average air-sea disequilibrium is only 2 µatm. Temperature-normalized fCO …

North Pacific Internal Tides From The Aleutian Ridge: Altimeter Observations And Modeling, Patrick F. Cummins, Josef Y. Cherniawsky, Michael G. G. Foreman

Journal of Marine Research

Internal tides radiating into the North Pacific from the Aleutian Ridge near Amukta Pass are examined using 7 years of Topex/Poseidon altimeter data. The observations show coherent southward phase propagation at the M₂ frequency over a distance of at least 1100 km into the central Pacific. Barotropic and baroclinic models are applied to study this internal tidal signal. Results from the barotropic model show that the strongest cross-slope volume and energy fluxes occur in the vicinity of Amukta Pass, helping to establish this region as an important site for baroclinic energy conversion along the eastern half of the ridge. …

Internal And Interfacial Tides: Beam Scattering And Local Generation Of Solitary Waves, Theo Gerkema

Journal of Marine Research

Analytical solutions of a linear internal-tide generation problem are presented for a stratification that involves both an interface (thermocline) and a lower layer of constant stratification. It is shown that an internal tidal beam scatters strongly at a moderately developed thermocline but much less at a thermocline that is either very weak or very strong. This scattering goes along with a local wave activity at the thermocline as well as with a downward leaking from the thermocline. It is argued that these processes offer a clue to explaining observations in the Bay of Biscay of 'local generation' of internal soliton …

The Impact Of Model Configuration In Studies Of Buoyant Coastal Discharge, Richard W. Garvine

Journal of Marine Research

Observations and model studies of large-scale buoyant plumes show three major types for the horizontal distribution of density. Type 1 represents the typical coastal freshwater plume of observations. The buoyant discharge turns right in the northern hemisphere (toward downshelf) under earth rotation at its source. Type 2 is common in many numerical model studies. Most of the buoyant water at the inlet turns left (upshelf) along the coast to form a continuously growing intrusion. Type 3 turns right but exhibits a massive anticyclonic bulge which grows with time; its coastal current is weak and carries a small fraction of the …

The Evolution And Energetics Of Large Amplitude Nonlinear Internal Waves On The Portuguese Shelf, D. R. G. Jeans, T. J. Sherwin

Journal of Marine Research

Intensive in-situ observations of nonlinear internal waves on the Portuguese shelf were made in August 1994, including measurements of the same wavepacket at three locations as it propagated on-shelf. The waves were characterized by sudden isotherm depressions of up to 45 m lasting 10-35 minutes, accompanied by current surges of up to 0.45 m s^-1 and shears of up to 0.7 m s^-1 over 60 m. The waves propagated away from the shelf break with an estimated phase speed of 0.57 m s^-1. The amplitude of the waves was comparable to the theoretical maximum. The kinetic …

Barotropic Instabilities Of The Agulhas Current System And Their Relation To Ring Formation, Henk A. Dijkstra, Wilhelmus P. M. De Ruijter

Journal of Marine Research

Recent work has shown that different steady retroflection regimes, a viscous and an inertial regime, exist for the Agulhas Current system in an idealized geometry. In this paper, instabilities of the barotropic steady flows are considered by solving the linear stability problem numerically. Barotropic instabilities occur as so-called Hopf bifurcations in the viscous regime, with corresponding patterns related to Rossby basin modes. Depending on the value of the reduced gravity parameter, these instabilities may introduce intermonthly to interannual variability into the retroflection region. Finite amplitude development of these instabilities display 'ring-like' localized anomaly patterns which travel around the tip of …

On The Summer Mesoscale Variability Of The Black Sea, Şükrü T. Beşiktepe, Carlos J. Lozano, Allan R. Robinson

Journal of Marine Research

The evolution of the Black Sea temperature, salinity and circulation, from large scale to mesoscale, is studied using a data-driven primitive equation simulation. The data are drawn from (i) a basin-wide hydrographic survey, CoMSBlack'92, obtained in the Summer of 1992; (ii) wind stress derived from wind analyses of the Sevastopol MSIA/URHI Office; (iii) climatological heat fluxes; and (iv) climatological river outflows. The primitive equation model is from the Harvard Ocean Prediction System. The simulation is used to examine the evolution of the circulation at mesoscale resolution, its dominant variabilities and dependencies in the summer period. The large-scale upper layer circulation …

The Origin Of Low-Frequency Variability Of Double-Gyre Wind-Driven Flows, Janine J. Nauw, Henk A. Dijkstra

Journal of Marine Research

Bifurcation analysis on flows in a two-layer shallow-water model is used to clarify the dynamical origin of low-frequency variability of the double-gyre wind-driven ocean circulation. In many previous model studies, generic low-frequency variations appear to be associated with distinct regimes, characterized by the level of kinetic energy of the mean flow. From these transient flow computations, the current view is that these regimes, and transitions between them, arise through a complex nonlinear interaction between the mean flow and its high-frequency instabilities (the eddies). On the contrary, we demonstrate here, for a particular (but relevant) case, that the origin of these …

Impact Of Sub-Mesoscale Physics On Production And Subduction Of Phytoplankton In An Oligotrophic Regime, Marina Lévy, Patrice Klein, Anne-Marie Treguier

Journal of Marine Research

Using a protocol of numerical experiments where horizontal resolution is progressively increased, we show that small-scale (or sub-mesoscale) physics has a strong impact on both mesoscale physics and phytoplankton production/subduction. Mesoscale and sub-mesoscale physics result from the nonlinear equilibration of an unstable baroclinic jet. The biogeochemical context is oligotrophy. The explicitly resolved sub-mesoscales, at least smaller than one fifth of the internal Rossby radius of deformation, reinforce the mesoscale eddy field and contribute to double the primary production and phytoplankton subduction budgets. This enhancement is due to the reinforced mesoscale physics and is also achieved by the small-scale frontal dynamics. …

A Bifurcation Study Of The Three-Dimensional Thermohaline Ocean Circulation: The Double Hemispheric Case, Wilbert Weijer, Henk A. Dijkstra

Journal of Marine Research

Within a low-resolution primitive-equation model of the three-dimensional ocean circulation, a bifurcation analysis is performed of double-hemispheric basin flows. Main focus is on the connection between results for steady two-dimensional flows in a nonrotating basin and those for three-dimensional flows in a rotating basin. With the use of continuation methods, branches of steady states are followed in parameter space and their linear stability is monitored. There is a close qualitative similarity between the bifurcation structure of steady-state solutions of the two- and three dimensional flows. In both cases, symmetry-breaking pitchfork bifurcations are central in generating a multiple equilibria structure. The …

Particle Flux In The Rainbow Hydrothermal Vent Field (Mid-Atlantic Ridge): Dynamics, Mineral And Biological Composition, Alexis Khripounoff, Annick Vangriesheim, Philippe Crassous, Michel Segonzac, Ana Colaço, Daniel Desbruyères, Roxane Barthelemey

Journal of Marine Research

In order to provide information about the export and the distribution of hydrothermal particulate material to the surrounding deep ocean, four moorings were deployed in the vicinity of the hydrothermal Rainbow vent field (Mid-Atlantic Ridge, 36°14′N, 2250 m depth). The first mooring was a sediment trap with a current meter deployed at 2 m from a chimney of the Rainbow vent field and 1.5 m above the bottom (a.b.) for 16 days. It represented the reference for the initial composition of particles produced by the vent. The total mean mass particle flux (6.9 g m^-2 d^-1) was …

Mechanism Of Offshore Nutrient Supply In The Western Arabian Sea, Michio Kawamiya

Journal of Marine Research

The mechanism to maintain the high surface chlorophyll in the western Arabian Sea during the southwest monsoon (SWM) season is studied with an eddy-permitting, biological-physical coupled model. Using a set of artificial tracers, it is revealed that horizontal transport of nutrient subsequent to the coastal upwelling is by far more important than the open ocean upwelling due to the Ekman pumping. The horizontal transport can be classified into three processes, the Ekman transport, transport by the large-scale circulation and that by the mesoscale currents. In the model, the first has only a minor effect within the area of high chlorophyll …

The Role Of Colonization In Establishing Patterns Of Community Composition And Diversity In Shallow-Water Sedimentary Communities, Paul V. R. Snelgrove, J. Frederick Grassle, Judith P. Grassle, Rosemarie F. Petrecca, Karen I. Stocks

Journal of Marine Research

To determine whether pattern and diversity in benthic sedimentary communities are set primarily at colonization or by post-settlement biological interactions, we collected faunal cores and conducted reciprocal sediment transplant experiments at a sandy and a muddy site at 12 m depth, ~3 km apart off New Jersey. Multivariate analyses of cores collected at these sites in September 1994 indicated differences in the taxa determining local pattern, with the bivalve Spisula solidissima and the polychaete Polygordius sp. being dominant at the sandy site, and oligochaetes, several polychaete species and the bivalve Nucula annulata dominant at the muddy site. Individual cores from …

Phytoplankton Seasonal Distribution From Seawifs Data In The Agulhas Current System, E. Machu, V. Garçon

Journal of Marine Research

The interocean conduit for warm Indian Ocean water into the Atlantic Ocean is the Agulhas system which plays an important role in maintaining the global thermohaline circulation. The frontal system formed by the Agulhas Return Current (ARC) and the Subtropical Convergence (STC) is also a region of intense mesoscale activity presenting enhanced levels of biological production and chlorophyll a. We jointly analyzed three different satellite data sets to relate the remotely sensed distribution of phytoplankton (SeaWiFS ocean color data) to the dynamical environment (Topex/Poséidon-ERS sea level anomalies-SLA- and sea-surface temperature-SST-) to gain insight into the seasonal behavior of the …

A Data Assimilative Marine Ecosystem Model Of The Central Equatorial Pacific: Numerical Twin Experiments, Marjorie A. M. Friedrichs

Journal of Marine Research

A five-component, data assimilative marine ecosystem model is developed for the high-nutrient low-chlorophyll region of the central equatorial Pacific (0N, 140W). Identical twin experiments, in which model-generated synthetic 'data' are assimilated into the model, are employed to determine the feasibility of improving simulation skill by assimilating in situ cruise data (plankton, nutrients and primary production) and remotely-sensed ocean color data. Simple data assimilative schemes such as data insertion or nudging may be insufficient for lower trophic level marine ecosystem models, since they require long time-series of daily to weekly plankton and nutrient data as well as adequate knowledge of the …

Central Equatorial Pacific Zonal Currents. I: The Sverdrup Balance, Nonlinearity And Tropical Instability Waves. Annual Mean Dynamics, D. E. Harrison, R. D. Romea, S. H. Hankin

Journal of Marine Research

Several recent observational studies of central Pacific equatorial current dynamics have suggested that, in the vertical integral between the surface and the thermocline, the linear equatorial Sverdrup balance holds. However, in a high vertical resolution ocean general circulation model, we find that nonlinearity is an order (1) element of the local and the vertically integrated balances on and near the equator at 140W. Although this OGCM has been used in many studies of the tropical Pacific, its equatorial zonal momentum equation balances have never been described in detail and compared with observations. We describe the annual mean balances here, identify …

The Impact Of Model-Error Correlation On Regional Data Assimilative Models And Their Observational Arrays, Philip S. Bogden

Journal of Marine Research

Data assimilative models often minimize a penalty functional that measures model adjustment and model-data misfit. The penalty functional builds assumptions about model error into the analysis. Usually, errors from different parts of the model (e.g., dynamics and boundary conditions) are presumed to be uncorrelated. This is clearly not a valid assumption in regional models where uncertain large-scale forcing affects open-ocean boundary conditions. In this study, calculations with a regional wind-driven inverse model provide a specific example where model error from uncertain wind stress is correlated with model error from uncertain open boundary conditions. This physically realistic scenario motivates development of …

The Near-Surface Velocity And Potential Vorticity Structure Of The Gulf Stream, T. Rossby, H. M. Zhang

Journal of Marine Research

Using Acoustic Doppler Current Profiler and XBT data between 1992 and 1999 from a container vessel that crosses the Gulf Stream twice weekly near 70W, we examine the near-surface velocity, thermal and vorticity structure of the current. These data come from an ongoing sampling program that has as its overall objective to measure the currents between New York and Bermuda to provide a high-quality database for studies of variability and long-term trends in the region. These Gulf Stream sections, when averaged in natural or stream coordinates, exhibit a remarkable double-exponential structure. The scale-widths of the lateral shear north and south …

Effects Of Topography On The Beta-Drift Of A Baroclinic Vortex, Georgi Sutyrin

Journal of Marine Research

The propagation of compact, surface-intensified vortices over a topographic slope on the beta-plane is studied in the framework of a two-layer model. A perturbation theory is derived for a circular vortex in the upper layer with the lower layer at rest as a basic state. An integral momentum balance for the upper layer is used to obtain expressions for the velocity of the vortex center assuming the flow is quasi-stationary to leading order. This approach allows the calculation of the lower-layer flow pattern as a function of the interface shape and the slope orientation. The essential part of the lower-layer …

Modeling Water Column Structure And Suspended Particulate Matter On The Middle Atlantic Continental Shelf During The Passages Of Hurricanes Edouard And Hortense, Alejandro J. Souza, Tommy D. Dickey, Grace C. Chang

Journal of Marine Research

The present contribution is motivated by the desire to elucidate the processes that contributed to the evolution of observed thermal structure and resuspension of particulate matter during and after the passages of two hurricanes, Edouard and Hortense, within a two-week period in late-summer 1996. A unique set of high temporal frequency measurements of the vertical structures of physical and optical properties was obtained at a mooring site near the Middle Atlantic Bight continental shelf-break (70 m water depth). These data provided insight and initial conditions for the physical model used for this study. The model accounted for wind and bottom …

Water Quality And Benthic Invertebrates Within A Prairie Pothole Lake Basin, Kelly Connelly, N. H. Troelstrup Jr.

Oak Lake Field Station Research Publications

Oak Lake (Brookings County, SD) is a small, semi-permanent prairie pothole lake basin on the eastern ridge of the Prairie Des Coteau. This lake is managed to support immersion contact recreation, marginal warmwater fish life propagation and livestock and wildlife watering. In addition, the western shoreline of this basin is bordered by the Oak Lake Field Station, a teaching and research facility managed by South Dakota State University. Water quality and biotic integrity of Oak Lake have been monitored biweekly during the ice-free season over the period 1994-2000. Samples were collected from three mid-basin points using standard methods of water …

Effects Of Un-Ionized Ammonia On Hydropsyche Morosa Hagen Larava Net And Retreat Construction, Althea Caraway, N. H. Troelstrup Jr.

Oak Lake Field Station Research Publications

The objectives of this study were to (1) describe natural variability in retreat and net mesh dimensions and retreat and net tending behavior for the hydropsychid caddisfly Hydropsyche morosa Hagen and (2) perform laboratory experiments to determine the influence of un-ionized ammonia on H. morosa retreat and net construction. H. morosa were collected from fifteen streams in eastern South Dakota and head capsules, nets, and retreats were photographed and measured. Caddis were exposed to 0.00, 0.025, 0.05 and 0.1 mg/L un-ionized ammonia for 48 and 96 hours within experimental stream chambers. Data indicate that exposing caddis to un-ionized ammonia caused …

Nutrient Loadings And Phytoplankton Dymanics Within A Power Plant Cooling Pond, Amy L. Gronke, N. H. Troelstrup Jr.

Oak Lake Field Station Research Publications

Cultural eutrophication within the Ottertail Power Plant cooling pond has led to frequent blooms of noxious algae, fish kills, and odor problems. The objectives of this project were to (1) estimate phosphorus and nitrogen loadings to the cooling pond and (2) evaluate seasonal phytoplankton dynamics and pond trophic state. Water chemistries and phytoplankton samples were collected monthly over the period January 1 to December 31, 1998 and 1999. Total nitrogen, total phosphorus, and phytoplankton counts were analyzed according to standard limnological methods. Sources of nutrient loading include Big Stone Lake water, fly ash pond return flows, domestic wastewater and overwintering …

Optimal Macroinvertebrate Metrics For The Assessment Of A Northern Prairie Stream, A. M. Larson, Nels H. Troelstrup Jr.

Oak Lake Field Station Research Publications

This research was conducted to (1) determine an optimal suite of macroinvertebrate metrics and (2) test the effectiveness of standard EPA biological assessment methods for identification of stream degradation. Invertebrate samples were taken from 18 sites on Bachelor and Brookfield Creeks in Moody County, South Dakota once per month from April through September 1998 and 1999. Data were applied to 51 invertebrate metrics which were (1) randomly selected in sets of 10, (2) grouped as per Plafkin et al. (1989) (3) optimized by minimizing reference site variability and maximizing site discriminatory power (Barbour et al., 1999), and (4) optimized using …