Optical and chemical characterization of base-extracted particulate organic matter in coastal marine environments

Brym, Adeline; Paerl, Hans W.; Montgomery, Michael T.; Handsel, Lauren T.; Ziervogel, Kai; Osburn, Christopher L.

doi:10.1016/j.marchem.2014.03.006

Cited by 66 publications

(51 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…having a slightly narrower range (4-36%) ( Table 3). These extraction efficiencies were consistent with those reported in Brym et al (2014). Greater extraction efficiencies occurred earlier in growth (e.g., exponential phase 21-78%) and decreased with the duration of the experiment with the lowest extraction efficiencies occurring after 6 weeks of degradation (4-24%, T 3 ).…”

Section: Carbon Concentrations and Poc/ponsupporting

confidence: 90%

“…After 24 h, extracts were neutralized with concentrated hydrochloric acid, then filtered using a 0.2 µm porosity Sterivex-GP polyethersulfone filter (EMD) (Brym et al, 2014). The filtrate was analyzed for absorbance and fluorescence in the same manner as CDOM.…”

Section: Optical Measurementsmentioning

confidence: 99%

“…Two types of fluorescence are typically described, amino acid-like compounds and humiclike compounds (Coble, 2007), and have been attributed to autochthonous (e.g., primary production) and allochthonous (e.g., terrestrial) production, respectively (Coble, 1996;Yamashita and Tanoue, 2003). Fluorescence of base-extracted particulate organic matter (BEPOM), has been established as a relatively new technique that allows for the optical properties and sources of intracellular fluorophores in POM to be determined (Brym et al, 2014). This work has suggested strong discrete fluorophores including amino acids in estuarine and coastal ocean POM, while studies investigating CDOM production from phytoplankton have confirmed strong amino acid-like fluorescence in axenic cultures with additional fluorescence in the region of humiclike fluorescence for some species (Romera-Castillo et al, 2010;Fukuzaki et al, 2014).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Formation of Chromophoric Dissolved Organic Matter by Bacterial Degradation of Phytoplankton-Derived Aggregates

et al. 2018

Self Cite

View full text Add to dashboard Cite

Organic matter produced and released by phytoplankton during growth is processed by heterotrophic bacterial communities that transform dissolved organic matter into biomass and recycle inorganic nutrients, fueling microbial food web interactions. Bacterial transformation of phytoplankton-derived organic matter also plays a poorly known role in the formation of chromophoric dissolved organic matter (CDOM) which is ubiquitous in the ocean. Despite the importance of organic matter cycling, growth of phytoplankton and activities of heterotrophic bacterial communities are rarely measured in concert. To investigate CDOM formation mediated by microbial processing of phytoplankton-derived aggregates, we conducted growth experiments with non-axenic monocultures of three diatoms (Skeletonema grethae, Leptocylindrus hargravesii, Coscinodiscus sp.) and one haptophyte (Phaeocystis globosa). Phytoplankton biomass, carbon concentrations, CDOM and base-extracted particulate organic matter (BEPOM) fluorescence, along with bacterial abundance and hydrolytic enzyme activities (α-glucosidase, β-glucosidase, leucine-aminopeptidase) were measured during exponential growth and stationary phase (∼3-6 weeks) and following 6 weeks of degradation. Incubations were performed in rotating glass bottles to keep cells suspended, promoting cell coagulation and, thus, formation of macroscopic aggregates (marine snow), more similar to surface ocean processes. Maximum carbon concentrations, enzyme activities, and BEPOM fluorescence occurred during stationary phase. Net DOC concentrations (0.19-0.46 mg C L −1 ) increased on the same order as open ocean concentrations. CDOM fluorescence was dominated by protein-like signals that increased throughout growth and degradation becoming increasingly humic-like, implying the production of more complex molecules from planktonic-precursors mediated by microbial processing. Our experimental results suggest that at least a portion of open-ocean CDOM is produced by autochthonous processes and aggregation likely facilitates microbial reprocessing of organic matter into refractory DOM.

show abstract

Section: Carbon Concentrations and Poc/ponsupporting

confidence: 90%

Section: Optical Measurementsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Formation of Chromophoric Dissolved Organic Matter by Bacterial Degradation of Phytoplankton-Derived Aggregates

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…Catalá et al (2016) demonstrated that the global depth distribution tryptophan-like FDOM component has a local maximum associated with a chlorophyll a maximum. The linkage between protein-like components and chlorophyll a concentration shown qualitatively in the global ocean by Stedmon and Nelson (2015) and Catalá et al (2016) was previously confirmed quantitatively in mesocosm studies, for example, Romera-Castillo et al (2010), which indicated that phytoplankton excreted tryptophan-like fluorophores, and tryptophan-like component concentration has been related to primary production (Brym et al, 2014). In situ quantitative correlation between chlorophyll a concentrations and fluorescence intensity of the protein-like FDOM fraction has been observed and documented recently.…”

Section: Distribution Of Fdom Components In the Ocean And Their Depenmentioning

confidence: 54%

Characteristics of chromophoric and fluorescent dissolved organic matter in the Nordic Seas

et al. 2018

View full text Add to dashboard Cite

Abstract. Optical properties of chromophoric (CDOM) and fluorescent dissolved organic matter (FDOM) were characterized in the Nordic Seas including the West Spitsbergen Shelf during June-July 2013, 2014, and 2015. The CDOM absorption coefficient at 350 nm, a CDOM (350) showed significant interannual variation (T test, p < 0.00001). In 2013, the highest average a CDOM (350) values (a CDOM (350) = 0.30 ± 0.12 m −1 ) were observed due to the influence of cold and low-salinity water from the Sørkapp Current (SC) in the southern part of the West Spitsbergen Shelf. In 2014, a CDOM (350) values were significantly lower (T test, p < 0.00001) than in 2013 (average a CDOM (350) = 0.14 ± 0.06 m −1 ), which was associated with the dominance of warm and saline Atlantic Water (AW) in the region, while in 2015 intermediate CDOM absorption (average a CDOM (350) = 0.19 ± 0.05 m −1 ) was observed. In situ measurements of three FDOM components revealed that fluorescence intensity of protein-like FDOM dominated in the surface layer of the Nordic Seas. Concentrations of marine and terrestrial humic-like DOM were very low and distribution of those components was generally vertically homogenous in the upper ocean (0-100 m). Fluorescence of terrestrial and marine humic-like DOM decreased in surface waters (0-15 m) near the sea ice edge due to dilution of oceanic waters by sea ice meltwater. The vertical distribution of protein-like FDOM was characterized by a prominent subsurface maximum that matched the subsurface chlorophyll a maximum and was observed across the study area. The highest protein-like FDOM fluorescence was observed in the Norwegian Sea in the core of warm AW. There was a significant relationship between the proteinlike fluorescence and chlorophyll a fluorescence (R 2 = 0.65, p < 0.0001, n = 24 490), which suggests that phytoplankton was the primary source of protein-like DOM in the Nordic Seas and West Spitsbergen Shelf waters. Observed variability in selected spectral indices (spectral slope coefficient, S 300-600 , carbon-specific CDOM absorption coefficient at 254 and 350 nm, SUVA 254 , a * CDOM (350)) and the nonlinear relationship between CDOM absorption and the spectral slope coefficient also indicate a dominant marine (autochthonous) source of CDOM and FDOM in the study area. Further, our data suggest that a CDOM (350) cannot be used to predict dissolved organic carbon (DOC) concentrations in the study region; however the slope coefficient (S 300-600 ) shows some promise in being used.

show abstract

“…DOM's role in the microbial loop adds complexity to the linkages between optical and chemical properties of DOM in the surface ocean. Recent discoveries of base-extractable DOM from particulate organic matter (BEPOM) exhibits fluorescence patters consistent with biochemical sources from phytoplankton and bacterioplankton confirm autochthonous processes in shaping DOM's optical properties (Osburn et al, 2012;Nelson and Siegel, 2013;Brym et al, 2014). Aparicio et al investigated the importance of the microbial degradation in leading to potential "recalcitrance" of DOM by exposing bathypelagic Atlantic Ocean bacteria to simple substrates (sugars, amino acids) and to humic acid.…”

mentioning

confidence: 99%

Editorial: Linking Optical and Chemical Properties of Dissolved Organic Matter in Natural Waters

Osburn

Bianchi

2016

Front. Mar. Sci.

Self Cite

View full text Add to dashboard Cite

Optical and chemical characterization of base-extracted particulate organic matter in coastal marine environments

Cited by 66 publications

References 65 publications

Formation of Chromophoric Dissolved Organic Matter by Bacterial Degradation of Phytoplankton-Derived Aggregates

Formation of Chromophoric Dissolved Organic Matter by Bacterial Degradation of Phytoplankton-Derived Aggregates

Characteristics of chromophoric and fluorescent dissolved organic matter in the Nordic Seas

Editorial: Linking Optical and Chemical Properties of Dissolved Organic Matter in Natural Waters

Contact Info

Product

Resources

About