A5070047274- Marine and coastal ecosystems
- Microbial Community Ecology and Physiology
- Protist diversity and phylogeny
- Aquatic Ecosystems and Phytoplankton Dynamics
- Marine Biology and Ecology Research
- Space Exploration and Technology
- Isotope Analysis in Ecology
- Spaceflight effects on biology
- Cardiovascular and Diving-Related Complications
- Polar Research and Ecology
- Algal biology and biofuel production
- Syphilis Diagnosis and Treatment
- High Altitude and Hypoxia
- Environmental DNA in Biodiversity Studies
- Wastewater Treatment and Nitrogen Removal
- Ocean Acidification Effects and Responses
- Human-Automation Interaction and Safety
- Selenium in Biological Systems
- Child Abuse and Trauma
- Mercury impact and mitigation studies
- Aquatic Ecosystems and Biodiversity
- Child Welfare and Adoption
- Amphibian and Reptile Biology
- Soil and Water Nutrient Dynamics
- Marine and environmental studies
Temple University
2015-2024
Johnson Space Center
2021
Wyle (United States)
2016-2019
The University of Texas Medical Branch at Galveston
2017-2018
National Aeronautics and Space Administration
2018
Psychiatric Medicine Associates
2018
The University of Texas MD Anderson Cancer Center
2009
Rutgers, The State University of New Jersey
1997
Franklin Institute
1994
Woods Hole Oceanographic Institution
1992
Bacterivory in eutrophic Lake Oglethorpe, Georgia, was determined by direct observation of tracer particle uptake all members the planktonic community. Heterotrophic flagellates dominated grazing at times, accounting for 49–81% on an areal basis and up to 98% some depths. Pigmented (mixotrophic) were major grazers during winter spring blooms, when they contributed 45% community 79% depths maximum abundance. In late early summer, rotifers ciliates responsible as much 25 30% bacterivory...
Despite differences in the species compositions and absolute abundances of planktonic microorganisms fresh-and saltwater, there are broad similarities microbial food webs across systems.Relative bacteria nanoplanktonic protozoa (HNAN, primarily heterotrophic flagellates) similar marine freshwater environments, which suggests analogous trophic relationships.Ranges microbe fresh waters overlap, seasonal changes within an ecosystem often as great between systems productivities.Densities...
Arranging organisms into functional groups aids ecological research by grouping (irrespective of phylogenetic origin) that interact with environmental factors in similar ways. Planktonic protists traditionally have been split between photoautotrophic “phytoplankton” and phagotrophic “microzooplankton”. However, there is a growing recognition the importance mixotrophy euphotic aquatic systems, where many often combine modes nutrition. Such do not align traditional dichotomy phytoplankton...
Protozoa are now being recognized as important members of planktonic food webs. This is due to the inclusion microbial links in our paradigm trophic relationships. Heterotrophic microflagellates and ciliates major grazers bacteria. They can stimulate production through nutrient recycling transform into larger particles, which then available for macroconsumers. In this paper we add new groups, small (< 20 μm) myxotrophic flagellates, web.
Utilization of dissolved organic nitrogen (DON) from natural (forests) and anthropogenic (animal pastures, urban/suburban storm water runoff) sources (three sites per source) by estuarine plankton communities was examined in spring, summer, fall. The proportion DON utilized ranged 0 to 73%. Overall, runoff had a higher bioavailable (59% ± 11) compared agricultural pastures (30% 14) forests (23% 19). bioavailability varied seasonally; however, the seasonal pattern differed for three sources....
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 159:1-12 (1997) - doi:10.3354/meps159001 Contribution of dissolved organic nitrogen from rivers estuarine eutrophication S. P. Seitzinger*, R. W. Sanders** Academy Natural Sciences, Division Environmental Research, 1900 Benjamin Franklin Parkway, Philadelphia, Pennsylvania 19103, USA Present addresses:...
Atmospheric deposition is recognized as a potentially large source of inorganic nutrients to many ecosystems. In marine systems, where nitrogen (N) the nutrient typically limiting phytoplankton growth, rainwater often significant N. Although considerable portion atmospheric N in form organic N, only has been considered by most previous studies. Laboratory experiments presented here indicate that dissolved (DON) from can stimulate productivity coastal bacteria and phytoplankton. A percent DON...
ABSTRACT Some protists from both marine and freshwater environments function at more than one trophic level by combining photosynthesis panicle ingestion. Photosynthetic algae several taxa (most commonly chrysomonads dinoflagellates) have been reported to ingest living prey or nonliving particles, presumably obtaining part of their carbon and/or nutrients phagocytosis. Conversely, some ciliates sarcodines sequester chloroplasts after ingestion algal prey. Plastid retention “chloroplast...
The water columns of lakes and oceans provide a diverse habitat gradient in which light, temperature, food, predation risk all change with depth. Many planktonic organisms exhibit diel vertical migrations (DVM) response to daily oscillations many these variables. DVM theory often assumes that surface waters are more food‐rich than deeper, subsurface layers proceeds try explain why zooplankton migrate out beneficial during the day. Here, we test assumption food is best by feeding two common...
Growth, grazing, C and nutrient in corporation by the mixotrophic phytoflagellate Poterioochromonas malhamensis were examined under various light regimes presence of heat‐killed bacteria. readily ingested bacteria all culture treatments containing bacteria, growth rates protist much greater for heterotrophic (bacterivorous) than phototrophic growth. incorporation efficiencies virtually identical to P during growth, but N somewhat lower nearly treatments. Algal cultures with was similar...
Mixotrophy, the combination of phototrophy and heterotrophy within same individual, is widespread in oceanic systems. Yet, neither presence nor ecological impact mixotrophs has been identified an Arctic marine environment. We quantified nano- picoplankton during early autumn Beaufort Sea Canada Basin determined relative rates bacterivory by heterotrophs mixotrophs. Results confirmed previous reports low microbial biomass for communities autumn. The was relatively low, ranging from 0.6 ×...
This first comprehensive analysis of the global biogeography marine protistan plankton with acquired phototrophy shows these mixotrophic organisms to be ubiquitous and abundant; however, their differs markedly between different functional groups. These mixotrophs, lacking a constitutive capacity for photosynthesis (i.e. non-constitutive NCMs), acquire phototrophic potential through either integration prey-plastids or endosymbiotic associations photosynthetic microbes. Analysis field data...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 192:103-118 (2000) - doi:10.3354/meps192103 Heterotrophic and mixotrophic nanoplankton predation on picoplankton in Sargasso Sea Georges Bank Robert W. Sanders1,*, Ulrike-G. Berninger2, Ee Lin Lim3,**, Paul F. Kemp4, David A. Caron3,*** 1Department of Biology, Temple University, Philadelphia, Pennsylvania...
AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsSpecials 22:175-184 (2000) - doi:10.3354/ame022175 Responses of bacterioplankton and phytoplankton organic carbon inorganic nutrient additions in contrasting oceanic ecosystems David A. Caron1,*, Ee Lin Lim1,2, Robert W. Sanders2, Mark R. Dennett3, Ulrike-G. Berninger4 1Department Biological Sciences, University Southern...
Abundances of heterotrophic (HF), autotrophic (AF), and mixotrophic (MF) nanoflagellates in Lake Oglethorpe, Georgia, were the range 10 2 –10 4 cells ml −1 . Pigmented nonpigmented flagellate abundances positively correlated with each other samples spanning a year, but not significantly to same physical parameters (temperature, oxygen, light). The highest density flagellates (> 1 × ) was found spring 1986 at surface, although most abundance peaks ranged from 7 3 occurred metalimnion...
Species composition and abundance of tintinnids other microzooplankton were studied in the Damariscotta River estuary, Maine, USA during period March 1981 to May 1982. Peak tintinnid abundances occurred spring summer exceeded 7 × 10 3 I −1 . Spearman rank correlation coefficients indicated that temperature, nanoplankton chlorophyll phaeopigments passing a 20 μn filter important factors correlating with total density. changed seasonally was similar both years. Non-loricate ciliates also most...
AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsSpecials 54:269-277 (2009) - DOI: https://doi.org/10.3354/ame01276 Mixotrophy: a widespread and important ecological strategy for planktonic sea-ice nanoflagellates in Ross Sea, Antarctica Stefanie Moorthi1,4,*, David A. Caron1, Rebecca J. Gast2, Robert W. Sanders3 1Department of Biological Sciences, University Southern...
Inhibitors of eucaryotes (cycloheximide and amphotericin B) procaryotes (penicillin chloramphenicol) were used to estimate bacterivory bacterial production in a eutrophic lake. Bacterial appeared be slightly greater than protozoan grazing the aerobic waters Lake Oglethorpe. Use penicillin cycloheximide yielded inconsistent results anaerobic water when was low. Production measured by inhibiting with did not always agree [ 3 H]thymidine estimates or differential filtration methods. Laboratory...