GLORIA — GEOMAR Library Ocean Research Information Access

Hits per page

hits 1 - 2 | 2 hits

Sorting

Unknown

Temporal and spatial variability of phytoplankton and mixotrophs in a temperate estuary (2022)

Millette, Nicole ; da Costa, Marcella ; Mora, Jordan ; [et al.]

Inter Research

add to mindlist on the mindlist

Details

Publication Date: 2022-05-27

Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Millette, N. C., da Costa, M., Mora, J. W., & Gast, R. J. Temporal and spatial variability of phytoplankton and mixotrophs in a temperate estuary. Marine Ecology Progress Series, 677, (2021): 17–3,. https://doi.org/10.3354/meps13850.

Description: A significant proportion of phototrophic species are known to be mixotrophs: cells that obtain nutrients through a combination of photosynthesis and prey ingestion. Current methods to estimate mixotroph abundance in situ are known to be limited in their ability to help identify conditions that favor mixotrophs over strict autotrophs. For the first time, we combine microscopic analysis of phototrophic taxa with immunoprecipitated bromodeoxyuridine (BrdU)-labeled DNA amplicon sequencing to identify and quantify active and putative mixotrophs at 2 locations in a microtidal temperate estuary. We analyze these data to examine spatial and temporal variability of phytoplankton and mixotrophs. Microscopy-based phototrophic diversity and abundances reveal expected seasonal patterns for our 2 stations, with the start of growth in winter and highest abundances in summer. Diatoms tend to dominate at the site with less stratification, while dinoflagellates and euglenids are usually more prominent at the stratified station. The BrdU-based mixotroph identifications are translated to the microscopy identification and abundances to estimate the proportion of mixotrophs (cells 〉10 µm in size) at both sites. The average proportion of potential mixotrophs is higher at the station with higher stratification (51%) compared to the station with lower stratification (30%), and potential mixotrophs tend to be higher in summer, although we did not conduct BrdU experiments in any of the other seasons. Combining the identification of active mixotrophs through the uptake of BrdU-labeled bacteria with robust abundance measurements can expand our understanding of mixotrophs across systems.

Description: N.C.M. was funded by a Woods Hole Sea Grant Postdoctoral Fellowship (award number NA14OAR4170074), and M.dC. was funded by a WHOI Summer Student Fellowship. This is VIMS contribution number 4057.

Keywords: Phytoplankton ; Mixotrophs ; Estuaries ; Chl a

Repository Name: Woods Hole Open Access Server

Type: Article

Permalink

	Location	Call Number	Limitation	Availability

Others were also interested in ...

PAPER (OA)

Fulltext

Unknown

Carbon dioxide fluxes reflect plant zonation and belowground biomass in a coastal marsh (2017)

Moseman-Valtierra, Serena M. ; Abdul-Aziz, Omar I. ; Tang, Jianwu ; [et al.]

John Wiley & Sons

add to mindlist on the mindlist

Details

Publication Date: 2022-05-26

Description: © The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ecosphere 7 (2016): e01560, doi:10.1002/ecs2.1560.

Description: Coastal wetlands are major global carbon sinks; however, they are heterogeneous and dynamic ecosystems. To characterize spatial and temporal variability in a New England salt marsh, greenhouse gas (GHG) fluxes were compared among major plant-defined zones during growing seasons. Carbon dioxide (CO2) and methane (CH4) fluxes were compared in two mensurative experiments during summer months (2012–2014) that included low marsh (Spartina alterniflora), high marsh (Distichlis spicata and Juncus gerardii-dominated), invasive Phragmites australis zones, and unvegetated ponds. Day- and nighttime fluxes were also contrasted in the native marsh zones. N2O fluxes were measured in parallel with CO2 and CH4 fluxes, but were not found to be significant. To test the relationships of CO2 and CH4 fluxes with several native plant metrics, a multivariate nonlinear model was used. Invasive P. australis zones (−7 to −15 μmol CO2·m−2·s−1) and S. alterniflora low marsh zones (up to −14 μmol CO2·m−2·s−1) displayed highest average CO2 uptake rates, while those in the native high marsh zone (less than −2 μmol CO2·m−2·s−1) were much lower. Unvegetated ponds were typically small sources of CO2 to the atmosphere (〈0.5 μmol CO2·m−2·s−1). Nighttime emissions of CO2 averaged only 35% of daytime uptake in the low marsh zone, but they exceeded daytime CO2 uptake by up to threefold in the native high marsh zone. Based on modeling, belowground biomass was the plant metric most strongly correlated with CO2 fluxes in native marsh zones, while none of the plant variables correlated significantly with CH4 fluxes. Methane fluxes did not vary between day and night and did not significantly offset CO2 uptake in any vegetated marsh zones based on sustained global warming potential calculations. These findings suggest that attention to spatial zonation as well as expanded measurements and modeling of GHG emissions across greater temporal scales will help to improve accuracy of carbon accounting in coastal marshes.

Description: NOAA National Estuarine Research Reserve Science Collaborative Grant Number: 03354; USDA National Institute of Food and Agriculture, Hatch Project Grant Number: 229286; National Science Foundation Grant Number: 1561941/1336911; NOAA NERRA Grant Number: NA09NOS4190153; National Science Foundation Experimental Program to Stimulate Collaborative Research Cooperative Agreement Grant Number: EPS-1004057

Keywords: Biological invasion ; Blue carbon ; Emissions ; Global climate changes ; Juncus gerardii ; Methane ; Nitrous oxide ; Sea-level rise ; Spartina alterniflora