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Final Report: Phytoplankton Community Structure as an Indicator of Coastal Ecosystem Health

EPA Grant Number: R828677C001
Subproject: this is subproject number 001 , established and managed by the Center Director under grant R828677
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: EAGLES - Atlantic Coast Environmental Indicators Consortium
Center Director: Paerl, Hans
Title: Phytoplankton Community Structure as an Indicator of Coastal Ecosystem Health
Investigators: Paerl, Hans , Fries, Steven , Luettich Jr., Richard A. , Noble, Rachel T. , Pinckney, James L. , Valdes, Lexia M. , Wyrick, Pamela
Institution: University of North Carolina at Chapel Hill
EPA Project Officer: Levinson, Barbara
Project Period: March 1, 2001 through February 28, 2003
RFA: Environmental Indicators in the Estuarine Environment Research Program (2000)
Research Category: Ecological Indicators/Assessment/Restoration

Description:

Objective:

The objectives of this research project were to:  (1) develop broadly applicable, phytoplankton-based indicators of estuarine and coastal ecological condition; and (2) link these indicators to nutrient and physical-chemical forcing features and remote sensing analyses of water column optical properties.

Summary/Accomplishments (Outputs/Outcomes):

Since April 2001, this project has been operational.  Indicator development, testing, and application work plans have been coordinated with ongoing water quality and habitat monitoring programs on the Neuse River Estuary (NRE):  Coastal Intensive Sites Network (CISNet), Modeling and Monitoring (ModMon) (http://www.marine.unc.edu/Neuse/ModMonexit EPA), and a ferry-based water quality monitoring program for the NRE and Pamlico Sound (PS) (http://www.ferrymon.orgexit EPA).  These programs have served as the backbone for the collection of nutrient, photopigment (chlorophylls and carotenoids), productivity, water optical property turbidity, and physical data needed to characterize the structure, function, and environmental controls of indicator phytoplankton communities comprising the base of the estuarine food web (e.g., ModMon, FerryMon, and autonomous vertical profiler).  We have analyzed and evaluated comprehensive diagnostic(of phytoplankton community composition) photopigment samples that are serving to establish a baseline of phytoplankton community composition against which we will be able to gauge trophic state and ecological change in response to a wide variety of environmental forcing features including nutrient inputs, salinity (reflecting freshwater inputs and residence-time), water clarity and other optical properties, zooplankton grazing, and toxic substances.  We also have been collecting in situ hydrographic, dissolved oxygen (DO), and water velocity data to allow calculation of the residence-time in the system.

Although this project is based principally on the use of biological responses as indicators of ecosystem health, these responses are mediated by the physical characteristics of the systems and directly linked with chemical responses within the systems.  Thus, it is important to account for these physical and chemical processes when assessing biological responses, especially when comparing systems regionally.  In this regard, we have assessed and quantified how physical circulation and mixing control stratification, impact vertical migrations and turbidity and determine residence times as well as DO levels, which control nutrient chemistry and the viability of multiple fisheries within the systems.

Background

Ecosystem diversity is an important property for assessing the environmental condition of estuaries.  Phytoplankton are major primary producers in these systems; hence, the diversity of this component affects ecosystem structure and function.  Diversity indices can be calculated easily and compared within and among different ecosystems to provide a relative bioindicator of ecosystem health.  The absolute value of the index is less important than how the index changes over time.  For example, an increasing diversity index value over time indicates an increase in phytoplankton diversity, a characteristic of stable, undisturbed ecosystems.  Alternatively, a decrease in the diversity index signals an increasing frequency and magnitude of phytoplankton blooms, a consequence of eutrophication and declining ecosystem health.

Ecological Indicator

Diagnostic photopigments (chlorophylls and carotenoids) are being developed and deployed as indicators of the phytoplankton taxonomic groups mediating estuarine primary production, harmful blooms, water quality food web dynamics, and overall ecological condition.  These indicators are in use in water quality and habitat monitoring programs on the NRE (ModMon), a ferry-based water quality monitoring program for the NRE and PS, the Chesapeake Bay (CB) Program (http://www.chesapeakebay.netexit EPA), and ongoing water quality assessments in Florida Bay, the Gulf of Mexico, and other estuarine and coastal systems.  These indicators serve as verification and calibration data sources for remote sensing of estuarine phytoplankton biomass and composition, enabling researchers and managers to scale up to whole ecosystem assessments of productivity and ecological condition.  Lastly, these indicators are being used to identify and distinguish human (e.g., nutrient enrichment) from climatic stressors affecting water quality and habitat condition.

Ecological Effect/Impact

Phytoplankton and associated physical-chemical indicators that are being developed and applied in this component project already have proven useful and applicable for evaluating ecosystem and regional responses to a variety of environmental stressors, including nutrient loads, changes in hydrologic characteristics, large scale fronts, and major storms including hurricanes.  In addition, they offer great promise as a data source for verification and calibration of remote-sensing of plankton production and composition for a range of estuarine and coastal water bodies nationally.  These indicators now are part of unattended water quality monitoring of estuaries and coastal sounds (Buzzelli, et al., 2003; Paerl, et al., 2003; Niemi, et al., 2004).  For example, water samples, from which these indicators are measured, are being collected using ferries to characterize the large-scale impacts of Hurricane Isabel (September 2003) on the PS (Paerl, 2005).

Environmental Application

Current applications include the use of diagnostic pigment (e.g., chlorophyll a [chl a]) concentrations as criteria for meeting allowable total maximum daily (nutrient) loads (TMDLs) as early warning indicators of harmful (toxic, hypoxia-generating) algal blooms, turbidity, and designations of nutrient-sensitive waters.  Analyses and interpretation of photopigment data in ongoing long-term monitoring programs in major estuarine and coastal systems (CB, PS, Narragansett Bay, Long Island Sound, Galveston Bay, and Florida Bay) are clarifying relationships between the abundance of specific phytoplankton taxonomic groups and various estuarine chemical and physical stressors.  Because of the nonlinear and complex associations between biological, chemical, and physical variables, we are using more robust data analysis procedures, including neural network analysis, to establish quantitative associations between these variables in space and time, which will help complement the U.S. Environmental Protection Agency’s (EPA) regional assessments of estuarine and coastal water/habitat quality (e.g., Environmental Monitoring and Assessment Program).

The effect of one of these chemical-physical factors, river flow, on phytoplankton abundance and community structure has been studied extensively in the NRE-PS continuum in North Carolina and in the CB in Maryland/Virginia.  Both systems are influenced to a great extent by freshwater inflow from the Neuse and Susquehanna Rivers, respectively, and by the resulting changes in water residence-time and nutrient availability (Paerl, et al., 2005).

Phytoplankton biomass and community structure in the NRE-PS was affected profoundly by changes in hydrology that resulted from droughts and/or large pulses in river flow associated with seasonal increases in rainfall or with tropical storms and hurricanes.  This especially was evident at the two endpoints of the study area, in the Upper NRE, Southwest PS, and Southeast PS regions.  Overall, elevated river flow rates were associated with reduced phytoplankton biomass and group-specific algal biomass in the Upper NRE region.  Downstream of the Upper NRE, the reverse effect was observed as total phytoplankton biomass and the biomass of chlorophytes, cryptophytes, cyanobacteria, diatoms, and dinoflagellates were increased during conditions of elevated river flow rates.  Conversely, during reduced river flow conditions, phytoplankton biomass was increased at upstream locations, where nutrients are less limiting for phytoplankton.  Dinoflagellates especially were reduced in abundance during periods of elevated river flow and reduced water residence-time in the Upper NRE.  Dinoflagellates appear to be both sensitive and ecologically relevant indicators of changes in hydrology in the Upper NRE, as they consistently are more abundant during periods of long residence-time, when flushing rates are minimal (Paerl, et al., 2006; Valdes, et al., 2006).

These trends suggest that phytoplankton were physically transported downstream during conditions of elevated river flow, an observation similar to that observed in the CB.  With recent predictions of increased tropical storm and hurricane activity, the elevated rainfall and river flow rates associated with these disturbances may increase phytoplankton biomass in the currently oligotrophic to mesotrophic regions of the estuarine continuum especially in the PS.  Increases in river flow rates can be used as an indicator of reduced biomass of all taxonomic groups in the Upper NRE and increased biomass of all groups downstream of this region.  The reverse applies to reduced river flow rates.

Seasonal phytoplankton community responses to changes in river flow rates were examined and compared between the NRE and the CB.  In both systems, the resulting variability in water residence-time strongly influenced seasonal and longer-term patterns of phytoplankton biomass and community composition (Paerl, et al., 2005; Valdes, et al., 2006).  In the CB, diatom abundance was increased during high-flow years (short residence time conditions), regardless of season, when compared to low-flow years.  Contrary to the CB, diatoms in the NRE were reduced in abundance during high-flow years.  This discrepancy possibly could be caused by the substantially reduced water residence times in the CB (1 to 3 weeks) when compared to the NRE (2 weeks to 2 months).  In addition, the native phytoplankton composition that characterizes these two systems is very different.  Diatoms are generally predominant in the CB, although all five taxonomic groups typically are found in similar proportions in the NRE (approximately 20%).  With the exception of winter, dinoflagellates were more prevalent  during low-flow years in the NRE and in the CB (spring months).  This phytoplankton group seemed to have greater abundance during these increased residence time conditions.  Because river flow is minimal during the summer, river flow rates have less of an impact in promoting dominance by either diatoms or dinoflagellates in both systems.  In contrast, cyanobacteria tend to be abundant mostly during the summer in both systems, when the distinction between low- and high-flow is minimized.  In the NRE, all phytoplankton groups except summer cyanobacteria populations showed decreased abundance during elevated-flow years when compared to low-flow years.  On a seasonal basis, changes in flow regimes co-occurred with changing irradiance and temperature patterns.  In addition, zooplankton, benthic invertebrate (shellfish), and herbivorous fish (e.g., menhaden) grazing, influenced phytoplankton abundance and dominance, thus creating a complex set of interactions with residence-time that controlled phytoplankton community structure.  These results indicated that physical-chemical forcing features strongly influenced estuarine phytoplankton dynamics mediating eutrophication.

Functional group diversity was an integrative measure of both the abundances of individuals within a group as well as the number of groups in the sample.  Biweekly phytoplankton group diversity values were calculated for the Neuse River over 10-years using CHEMTAX derived group abundances and expressed in units of chl a.  Linear regression analysis showed a significant (p = 0.011) increase in group diversity over this period and suggests that water quality conditions in this estuary may be improving slowly.  This is one example of how functional group diversity indices may provide a useful metric for quantifying ecosystem-scale community dynamics.  In addition, this approach allows for a nonparametric cross-system comparison of important ecosystem properties.

Physical and Chemical Assessments Coupled With Biological Indicators

Background.  Although our project is based principally on the use of biological responses as indicators of ecosystem health, these responses are mediated by the physical characteristics of the systems and linked directly with chemical responses within the systems.  Thus, it is important to account for these physical and chemical processes when assessing biological responses, especially when comparing systems regionally.  In particular, physical circulation and mixing control stratification, impact vertical migrations and turbidity, and determine residence times, whereas DO levels control nutrient chemistry and the viability of multiple fisheries within the systems.

Ecological Indicator.  We are collecting in situ DO, stratification, turbidity, and chl a data and mixing vertical profiles in the NRE and CB to help determine these critical parameters.  These measurements complement long-term (>10 years) databases on DO values along the axes of these estuaries.

Ecological Effect/Impact.  These data allow an assessment of the vertical distribution of algal biomass in the water column.  During low wind conditions, (e.g., less than 10 m/s) NRE data showed a persistent daily vertical migration of the chl a maximum, presumably in response to ambient light conditions.  At higher wind speeds, the water column became well mixed and turbid, caused by resuspended bottom material.  This information was critical for interpreting data from discrete water column samples and from near-surface sampling using remote sensing platforms.  The 10-plus-years of DO data, along the lengths of both estuaries, are being processed to determine relatively long-term trends in DO levels and oxygen consumption that can be compared to individual years in these and other systems.

Environmental Application.  State and federal watershed managers in North Carolina and elsewhere use DO and chl a values as criteria for TMDLs into coastal systems.  The above data will help provide a context for interpreting these data and for comparisons with other systems.

Bacterial and Viral Indicators of Ecosystem Condition

Background.  We conducted a two-pronged research approach, focusing on the autochthonous and allochthonous microorganisms of the NRE, to identify potential indicators of ecosystem condition at the microbial loop or microbial contaminant level, respectively.  Many of the allochthonous microorganisms are either bacterial and viral pathogens or indicators (such as Enterococcus spp. and Escherichia coli) that are introduced to the system via stormwater runoff, wastewater, sewage effluents, confined animal feeding operations, and agriculture operations.  These microorganisms were studied to develop an understanding of their dynamics, fate, and transport through the system.  The primary autochthonous microorganisms of interest for this project were Vibrio spp., a group of bacteria that are native to estuarine environments but also can include highly pathogenic species (e.g., Vibrio vulnificus, wound infections, septicemia).  In addition, we conducted research to develop virus probes of both heterotrophic bacterioplankton species and phytoplankton species in the NRE.  The approaches for developing indicators of ecosystem condition in the NRE at the prokaryotic and viral level are being applied in concert with the Paerl laboratory for development of phytoplankton-based indicators of ecosystem condition and as tools to determine levels of other potentially ecosystem disrupting species or processes (e.g., viral probes of harmful algal blooms [HAB] or growth of important native bacterial pathogens such as V. vulnificus).

Ecological Indicator.  Atlantic Coast Environmental Indicators Consortium (ACE INC) is developing broad level viral and bacterial indicators of ecosystem condition.  Our effort has been a multitiered effort that includes development of a variety of microbial level indicators of ecosystem condition.

The first approach was to conduct a preliminary assessment of bacterial diversity in the NRE and to isolate virus-host systems for use as potential probes of species composition on future studies in that estuarine environment.  The NRE is a system for which we have a vast amount of nutrient and phytoplankton data, but our investigation on the supporting roles of the microbial loop (i.e., bacterial productivity, bacterial diversity, viral and bacterial abundance) really has begun only in the last few years.  From Station 0 to Station 120, a total of 424 bacterial isolates were sequenced.  Station 120 showed the highest bacterial diversity, simply assessed by the number of different bacterial species identified.  Virus concentrates were created for each water sample and subjected to a variety of host bacterial species.  The viruses are being developed as probes of specific phytoplankton and bacteria species.  We successfully isolated 10 virus-host systems.  In future experiments, the laboratory propagated viruses can be tagged fluorescently and used in natural samples to probe for their host species in natural waters.  These virus-host systems are specific to heterotrophic bacteria.  In addition, two cyanophage host systems specific for the cyanobacterial bloom former Microcystis spp. have been isolated successfully and stored in the laboratory (data not shown).

We also documented dynamics of native and nonnative bacterial indicators and pathogens (such as enterococci [ENT] and V. vulnificus, respectively) in relation to hydrological variables, chl a, salinity, turbidity, total suspended solids (TSS), phytoplankton community composition, bacterial growth rates, inorganic and organic matter, particle load and distribution, stormwater loading, and viral and bacterial abundance, as evidence of ecosystem disruption.  Native bacterial species, such as V. vulnificus, are powerful indicators of public health risk for those using the waters for recreation and for food.

Vibrio bacteria are widely present throughout the NRE.  There is a strong seasonal variation in total culturable Vibrio spp. that is supported by findings of previous research (Brasher, et al., 1998; Motes, et al., 1998; Pfeffer, et al., 2003; Randa, et al., 2004).  Peak numbers of culturable Vibrio spp. were reached in the summer months and decreased precipitously in the winter, at some stations dropping below detectable levels.  In general, bottom waters tend to have higher total Vibrio counts than surface waters for any given station.  This is likely influenced by the increased salinity found in bottom waters, but we also are examining other parameters including nutrient status, particle loading, turbidity, and DO.

Key environmental variables correlated with Vibrio populations are salinity and temperature.  It is well known that Vibrio species have varying degrees of tolerance for changing salinities (Motes, et al., 1998; Randa, et al., 2004; Pfeffer, et al., 2003).  We have assessed the relationship between Vibrio spp. density and Chl a, and have found no statistically significant relationship.  During summer conditions in the NRE when cold temperatures are not a limiting factor, salinity becomes a key variable and total Vibrio counts increase with increasing salinity.  Our data show that salinity and temperature are important predictive factors for Vibrio spp. growth.  We also have observed a relationship of Vibrio spp. densities with total dissolved nitrogen, although the relationship is weak.  Multiple regression analysis has yielded the following predictive relationship for Vibrio spp. with environmental parameters: 

Log Vibrio = 0.641 + (0.0747 * Temp C) + (0.0794 * Salinity) - (0.0413 * DO) - (0.000176 * irradiance) + (0.00389 * TSS (mg/l)) - (0.00102 * TDN) + (0.00307 * Chl a) R2 = 0.71, p < 0.001.

Only those variables in bold showed significant relationships for predicting Vibrio spp. concentrations.  The regression analysis indicates a 71 percent ability to predict Vibrio spp. concentrations.

The Noble laboratory also has been working to develop a quantitative polymerase chain reaction (QPCR) assay for the rapid detection of Vibrio bacteria.  Currently, Taqman assays for V. vulnificus and V. parahaemolyticus based on published primer-probe sets (Panicker, et al., 2004; Iijima, et al., 2004) have been optimized and used to identify cultured Vibrio isolates from the NRE.  These assays also are being used to identify V. vulnificus and V. parahaemolyticus from archived bacterial filters from previous sampling in 2004.  V. vulnificus has been identified at surface and bottom samples at several sites in the NRE.  Further work is being done to develop these methods into quantitative assays including work on internal controls.

Ecological Impact/Effect.  Several of the above mentioned tools are being used as direct indicators of ecosystem disruption.  Current research in the Noble laboratory is being conducted to develop virus-host systems in the laboratory.  We have isolated successfully 10 bacteriophage-bacteria systems that can be used in the future to probe natural samples for the presence of specific bacterial species.  Isolation research for further systems is being conducted on bacteriophage, cyanophage, and algal viruses.

Bacterial indicators, such as ENT, are being used as direct indicators of the impacts of stormwater runoff and other pollution contributions to the NRE-PS, as they generally are not native to the estuarine environment.  Monitoring of fecal indicators in the NRE has revealed dynamics in ENT in surface waters.  When high levels of these organisms were present, most often concentrations were highest at the freshwater end (Station 0) of the NRE and decreased downstream, demonstrating inputs of allochthonous bacteria from stormwater.  Furthermore, these bacteria are direct indicators of the presence of fecal contamination in the estuary.  Qualitatively, levels of ENT did appear to increase during wet periods, in particular during May and September of 2004.  Ongoing research is focusing on development of an understanding of the relationships among the presence of fecal indicator bacteria (such as ENT, E. coli), other bacterial pathogens of concern (Vibrio spp.), indicators of large-scale anthropogenic perturbation (Microcystis and other phytoplankton blooms), and environmental parameters (particle suspensions).

Viral and bacteria abundance generally can be used to assess the balance of the microbial loop.   In estuarine and coastal systems alike, it is common for there to be a consistent virus to bacterial ratio (VBR) that generally ranges from 5-20.  We demonstrated that this trend holds true for both the upstream Streets Ferry Bridge station (generally freshwater) and the NRE Station 180, with a grand average VBR of 10.0 (+ 3.2).  Deviation from this trend can be used to assess ecosystem disruption at the base of the food chain, but our results demonstrate consistency with many other coastal and estuarine systems.

Environmental Application.  Another approach to our work has been to identify the role of particle attachment to fate and transport of both allochthonous and autochthonous bacterial species.  In doing this work, which is in progress, we have found that measures of the characteristics and sources of particle suspensions can provide an indicator of estuarine water quality.  In the NRE, runoff and phytoplankton were found in specific hydrographic regions as the dominant suspensions.

In waters with salinity below 3 psu, suspensions exhibited nearly constant particle size distributions and density through time, leading to a significant correlation between TSS and turbidity.  Turbidity is a measure of light scattering that can be measured rapidly and in situ.  Using turbidity to estimate TSS provides a powerful tool for estimating terrigenous inputs, including microbial contamination associated with the particles entering the estuary.

Surface waters with salinity above 3 psu contained very different suspensions.  Runoff particles were absent and suspensions often had clear peaks at certain diameters.  Upon closer examination, these peaks were found to represent phytoplankton populations whose cells were the dominant particles in the sample.  Diameters provided a measure of cell size, whereas fecal pellet volume (FPV) provided information about the distribution of phytoplankton biomass over time and space that compares well with chlorophyll.  Preliminary comparisons of microscope cell counts with particle counts have produced strong agreement over several orders of magnitude (10–105 cells per ml, unpublished data).  FPV and cell size data are being tested as complements to diagnostic pigments for species identification from monitoring data (manuscript in preparation).

Useful applications of the developed technology included use of viral and bacteria indicator and pathogen concentrations as criteria for meeting allowable TMDLs in estuarine waters.  Novel molecular methods, such as QPCR, are being developed (in conjunction with Richard Haugland at EPA’s National Exposure Research Laboratory) as rapid warning systems for the presence of pathogenic bacteria and viruses that represent serious public health risk.  The molecular methods, in conjunction with a suite of traditional culture based methods and hydrology parameters, allowed us to assess the impact of large-scale storm events (including both wind, rain, and resuspension) on mid-Atlantic estuaries.  The molecular methods also offered a rapid means to assess the presence of potentially dangerous phytoplankton, bacterial, and viral species, offering a viable means for tracking sources of pollution into the estuary.  Research on the presence of V. vulnificus in the NRE is being conducted in collaboration with the North Carolina Department of Environment and Natural Resources (DENR) HAB Program (the program is focused on not only HABs but also other agents of disease in estuarine waters) as part of a growing concern regarding the incidence of wound infections caused by V. vulnificus along the coasts of the nation.

Training and Educational Development

This project has focused largely on Graduate and Undergraduate student training.  Recently (since fall 2003), the Carolina Environmental Program’s field semester at University of North Carolina at Chapel Hill’s Institute of Marine Sciences (http://www.cep.unc.edu/level_2/field_sites.htmlexit EPA), has been a prime user of ACE INC generated indicator data and applications.  In addition, project results have been used via Web sites (http://www.aceinc.orgexit EPA, http://www.marine.unc.edu/neuse/modmonexit EPA, and http://www.ferrymon.orgexit EPA) to train middle school and high school teachers and students.  We are developing FerryMon as a public outreach and educational component to demonstrate use and application of ACE INC indicators for the PS.  Water quality and habitat information will be provided via our interactive Web site in user-friendly formats (like the Weather Channel) for use in the classroom (grades K-2 through University), public information (ferry kiosks, informational centers, museums), recreational users, stakeholder groups, and interested citizens worldwide.  Web sites also have been used to instruct technicians and data managers.


Outreach Activities

Drs. Paerl, Luettich, and Noble are involved in a variety of statewide and national scientific advisory and educational activities.  These include serving on North Carolina DENR’s Technical Advisory Committee (Luettich), North Carolina Division of Water Quality’s TMDL modeling group (Luettich), the North Carolina Water Resources Research Institute’s Technical Committee (Paerl), the Albemarle-PS National Estuary Program (NEP) Technical Advisory Committee (Paerl), North Carolina DENR’s Stormwater Outfall Rules Steering Committee (Noble),  Advisor to the Shellfish Sanitation Section of North Carolina DENR (Noble), the North Carolina Environmental Management Commission (Paerl); and providing technical and evaluative advice for a variety of stakeholder groups (Luettich and Paerl), including the Neuse River Foundation, the Pamlico River Advisory Board, the Wilson Bay Advisory Committee, and the Neuse Basin Council of Municipalities.  Nationally, Paerl has been involved in an advisory role in the EPA-CB Program (Chlorophyll Water Quality Criteria Team), the Tampa Bay NEP, the University of Rhode Island’s Narragansett Bay Program, the Florida Bay Technical Advisory Committee, the Gulf of Mexico Hypoxia Peer Review Panel, and the American Society of Limnology and Oceanography Policy Committee.  Noble has been involved in the National Aeronautics and Space Administration Advanced Environmental and Microbial Control Panel and is an American Society for Limnology and Oceanography representative to the National Water Quality Monitoring Council.

The principal investigators are sharing technological developments and evaluative approaches/tools with scientific and agency (state-, federal-, and international-level) colleagues as well as public educational institutions, media, and resource (i.e., fisheries, tourism) managers.  Examples of the utility, informational value, and application (scientifically, management, and public education) of data thus far obtained can be found on the ModMon and FerryMon Web Sites.

Contributions to State of Knowledge

The pigment-based and associated physical-chemical indicators that are being developed and applied in this component project have already proven useful and applicable for evaluating ecosystem and regional responses to a variety of environmental stressors, including nutrient loads, changes in hydrologic characteristics (salinity, circulation), large-scale frontal passages (i.e., “Noreasters”), and major storms including hurricanes (Paerl, et al., 2001, 2003, 2004; Niemi, et al., 2004).  In addition, they offer great promise as a data source for development, verification, and modification of remote-sensing of plankton production and community structure of a range of estuarine and coastal water bodies regionally and nationally (Paerl, et al., 2006;).

The QPCR-based assays in development through the Noble laboratory have significance for both the recreational and shellfish harvesting waters management agencies, as they have the potential to be used to generate useful results for management of these waters within hours, rather than the day-long time frame needed for currently used membrane filtration and multiple tube fermentation analyses that are conducted routinely.  The assays are being developed in collaboration with EPA, the University of North Carolina at Chapel Hill Office of Technology and Development, and Cepheid, Inc.

References:

Brasher CW, DePaola A, Jones DD, Bej AK. Detection of microbial pathogens in shellfish with multiplex PCR. Current Microbiology 1998;37:101-107.

Iijima Y, Asako NT, Aihara M, Hayashi K. Improvement in the detection rate of diarrhoeagenic bacteria in human stool specimens by a rapid real-time PCR assay. Journal of Medical Microbiology 2004;53:617-622.

Lewitus AJ, White DL, Tymowski RG, Geesey ME, Hymel SN, Noble PA. Adapting the CHEMTAX method for assessing phytoplankton taxonomic composition in southeastern U.S. estuaries. Estuaries 2005;28(1):160-172.

Motes ML, DePaola A, Cook DW, Veazey JE, Hunsucker JC, Garthright WE, Blodgett RJ, Chirtel SJ. Influence of water temperature and salinity on Vibrio vulnificus in Northern Gulf and Atlantic Coast oysters (Crassostrea virginica). Applied and Environmental Microbiology 1998;64:1459-1465.

Panicker G, Call DR, Krug MJ, Bej AK. Detection of pathogenic Vibrio spp. in shellfish by using multiplex PCR and DNA microarrays. Applied and Environmental Microbiology 2004a;70:7436-7444.

Panicker G, Myers ML, Bej AK. Rapid detection of Vibrio vulnificus in shellfish and Gulf of Mexico water by real-time PCR. Applied and Environmental Microbiology 2004;70:498-507.

Pfeffer C, Oliver JD. A comparison of thiosulphate-citrate-bile salts-sucrose (TCBS) agar and thiosulphate-chloride-iodide (TCI) agar for the isolation of Vibrio species from estuarine environments. Letters in Applied Microbiology 2003;36:150-151.

Pfeffer CS, Hite MF, Oliver JD. Ecology of Vibrio vulnificus in estuarine waters of eastern North Carolina. Applied and Environmental Microbiology 2003;69:3526-3531.

Randa MA, Polz MF, Lim E. Effects of Temperature and Salinity on Vibrio vulnificus Population Dynamics as Assessed by Quantitative PCR. Applied and Environmental Microbiology 2004;70:5469-5476.

Thompson JR, Randa MA, Marcelino LA, Tomita-Mitchell A, Lim E, Polz MF. Diversity and dynamics of a north atlantic coastal Vibrio community. Applied and Environmental Microbiology 2004;70:4103-4110.


Journal Articles on this Report: 21 Displayed | Download in RIS Format

Other subproject views: All 143 publications 32 publications in selected types All 29 journal articles
Other center views: All 441 publications 90 publications in selected types All 81 journal articles

Type Citation Sub Project Document Sources
Journal Article Buzzelli CP, Luettich RA, Powers SP, Peterson CH, McNinch JE, Pinckney JL, Paerl HW. Estimating the spatial extent of bottom-water hypoxia and habitat degradation in a shallow estuary. Marine Ecology-Progress Series 2002;230:103-112. R828677 (2001)
R828677C001 (Final)
R826938 (2000)
R826938 (Final)
R827957 (Final)
not available
Journal Article Buzzelli CP, Ramus JR, Paerl HW. Ferry-based monitoring of surface water quality in North Carolina estuaries. Estuaries 2003;26(4):975-984. R828677C001 (Final)
not available
Journal Article Groffman PM, Baron JS, Blett T, Gold AJ, Goodman I, Gunderson LH, Levinson BM, Palmer MA, Paerl HW, Peterson GD, Poff NL, Rejeski DW, Reynolds JF, Turner MG, Weathers KC, Wiens J. Ecological thresholds: the key to successful environmental management or an important concept with no practical application? Ecosystems 2006;9(1):1-13. R828677C001 (Final)
R828012 (Final)
R829012 (2004)
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  • Journal Article Millie DF, Weckman GR, Paerl HW, Pinckney JL, Bendis BJ, Pigg RJ, Fahnenstiel GL. Neural net modeling of estuarine indicators: hindcasting phytoplankton biomass and net ecosystem production in the Neuse (North Carolina) and Trout (Florida) Rivers, USA. Ecological Indicators 2006;6(3):589-608. R828677C001 (Final)
    not available
    Journal Article Niemi G, Wardrop D, Brooks R, Anderson S, Brady V, Paerl H , Rakocinski C, Brouwer M, Levinson B, McDonald M. Rationale for a new generation of ecological indicators for coastal waters. Environmental Health Perspectives 2004;112(9):979-986. R828677C001 (Final)
    R828675 (2004)
    R828675 (Final)
    R828684 (Final)
    R829458C003 (2003)
    R829458C008 (2003)
    R829458C008 (2004)
    not available
    Journal Article Paerl HW, Dennis RL, Whitall DR. Atmospheric deposition of nitrogen: Implications for nutrient over-enrichment of coastal waters. Estuaries 2002;25(4B):677-693. R828677C001 (Final)
    R826938 (2001)
    R826938 (Final)
    not available
    Journal Article Paerl HW, Steppe TF, Buchan KC, Potts M. Hypersaline cyanobacterial mats as indicators of elevated tropical hurricane activity and associated climate change. Ambio 2003;32(2):87-90. R828677C001 (Final)
    not available
    Journal Article Paerl HW, Dyble J, Moisander PH, Noble RT, Piehler MF, Pinckney JL, Steppe TF, Twomey LJ, Valdes LM. Microbial indicators of aquatic ecosystem change: current applications to eutrophication studies. FEMS Microbiology Ecology 2003;46(3):233-246. R828677C001 (Final)
    not available
    Journal Article Paerl HW, Valdes LM, Pinckney JL, Piehler MF, Dyble J, Moisander PH. Phytoplankton photopigments as indicators of estuarine and coastal eutrophication. BioScience 2003;53(10):953-964. R828677C001 (Final)
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    Journal Article Paerl HW, Steppe TF. Scaling up: the next challenge in environmental microbiology. Environmental Microbiology 2003;5(11):1025-1038. R828677C001 (Final)
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    Journal Article Paerl HW, Valdes LM, Peierls BL, Adolf JE, Harding Jr LW. Anthropogenic and climatic influences on the eutrophication of large estuarine ecosystems. Limnology and Oceanography 2006;51(1, Part 2):448-462. R828677C001 (Final)
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    Journal Article Paerl HW, Valdes LM, Piehler MF, Stow CA. Assessing the effects of nutrient management in an estuary experiencing climatic change: the Neuse River Estuary, North Carolina. Environmental Management 2006;37(3):422-436. R828677C001 (Final)
    R830652 (2004)
    R830652 (2005)
  • Abstract from PubMed
  • Full-text: SpringerLink Full Text
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  • Journal Article Paerl HW. Assessing and managing nutrient-enhanced eutrophication in estuarine and coastal waters: interactive effects of human and climatic perturbations. Ecological Engineering 2006;26(1):40-54. R828677C001 (Final)
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    Journal Article Paerl HW, Piehler MF, Valdes LM, Dyble J, Moisander PH, Pinckney JL, Steppe TF. Determining anthropogenic and climatically-induced change in aquatic ecosystems using microbial indicators: an integrative approach. Verhandlungen Internationale Vereinigung fur Theoretische und Angewandte Limnologie 2005;29(1):89-133. R828677C001 (Final)
    R830652 (2005)
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    Journal Article Peierls BL, Christian RR, Paerl HW. Water quality and phytoplankton as indicators of hurricane impacts on a large estuarine ecosystem. Estuaries 2003;26(5):1329-1343. R828677C001 (Final)
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    Journal Article Piehler MF, Dyble J, Moisander PH, Pinckney JL, Paerl HW. Effects of modified nutrient concentrations and ratios on the structure and function of the native phytoplankton community in the Neuse River Estuary, North Carolina, USA. Aquatic Ecology 2002;36(3):371-385. R828677C001 (Final)
    R826938 (Final)
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    Journal Article Swackhamer DL, Paerl HW, Eisenreich SJ, Hurley J, Hornbuckle KC, McLachlan M, Mount D, Muir D, Schindler D. Impacts of atmospheric pollutant on aquatic ecosystems. Issues in Ecology 2004;(12):2-23. R828677C001 (Final)
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    Journal Article Vahatalo AV, Wetzel RG, Paerl HW. Light absorption by phytoplankton and chromophoric dissolved organic matter in the drainage basin and estuary of the Neuse River, North Carolina (USA). Freshwater Biology 2005;50(3):477-493. R828677C001 (Final)
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    Journal Article Valdes-Weaver, Lexia M, Piehler MF, Pinckney JL, Howe KE, Rosignol K, Paerl HW. Long-term temporal and spatial trends in phytoplankton biomass and class-level taxonomic composition in the hydrologically variable Neuse-Pamlico estuarine continuum, North Carolina, USA. Limnology and Oceanography 2006;51(3):1410-1420. R828677C001 (Final)
    R830652 (2005)
  • Abstract: ASLO Abstract
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  • Journal Article Reynolds-Fleming JV, Fleming JG, Luettich Jr. RA. Portable autonomous vertical profiler for estuarine applications. Estuaries 2002;25(1):142-147. R828677C001 (Final)
    R826938 (Final)
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    Journal Article Whipple AC, Luettich Jr. RA, Seim HE. Measurements of reynolds stress in a wind driven Lagoonal Estuary. Ocean Dynamics (submitted, 2005). R828677C001 (Final)
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    Supplemental Keywords:

    phytoplankton, estuarine & coastal indicators, photopigments, nutrients, hydrology, water quality, habitat, ecosystem and regional scale, management, physical factors, climatology, hurricanes, nutrient management, TMDLs, modeling, remote sensing, ferry-based monitoring, , Ecosystem Protection/Environmental Exposure & Risk, Scientific Discipline, RFA, Ecosystem/Assessment/Indicators, Chemistry, Ecological Indicators, Environmental Engineering, Ecological Effects - Environmental Exposure & Risk, Ecosystem Protection, Monitoring/Modeling, water quality, aquatic ecosystem, climate model, remote sensing, atmospheric dispersion models, ecoindicator, fish habitats, Choptank River, photopigment indicator, estuarine ecoindicator, trophic effects, atmospheric chemistry, environmental measurement, environmental stress, coastal ecosystem, nutrient loading, estuarine ecosystems, zooplankton, ecological models, climate change effects, assessment models
    Relevant Websites:

    http://www.aceinc.orgexit EPA
    http://www.marine.unc.edu/Neuse/ModMonexit EPA
    http://www.ferrymon.orgexit EPA
    http://www.chesapeakebay.netexit EPA

    Progress and Final Reports:
    2002 Progress Report
    2003 Progress Report
    2004 Progress Report
    Original Abstract


    Main Center Abstract and Reports:
    R828677    EAGLES - Atlantic Coast Environmental Indicators Consortium

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R828677C001 Phytoplankton Community Structure as an Indicator of Coastal Ecosystem Health
    R828677C002 Trophic Indicators of Ecosystem Health in Chesapeake Bay
    R828677C003 Coastal Wetland Indicators
    R828677C004 Environmental Indicators in the Estuarine Environment: Seagrass Photosynthetic Efficiency as an Indicator of Coastal Ecosystem Health

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    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.


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