Dataset title: Examination of protein-like fluorophores in chromophoric dissolved organic matter (CDOM) in a wetland and coastal environment for the wet and dry seasons of the years 2002 and 2003 (FCE) Dataset ID: ST_ND_Jaffe_006 Research type: Short-term Dataset Creator Name: Dr. Rudolf Jaffe Position: Lead Principal Investigator Organization: Florida Coastal Everglades LTER Program Address: Florida International University University Park OE 148 Miami, Florida 33199 USA Phone: 305-348-2456 Fax: 305-348-4096 Email: jaffer@fiu.edu URL: http://serc.fiu.edu/sercindex/index.htm Metadata Provider Organization: Florida Coastal Everglades LTER Program Address: Florida International University University Park OE 148 Miami, FL 33199 USA Phone: 305-348-6054 Email: fcelter@fiu.edu URL: http://fcelter.fiu.edu Dataset Abstract Water samples are collected at the end of the dry and the wet season from all LTER sites and stored on ice until return to the lab. They are pre-filtered through pre-combusted GF/F filters and ultrafiltered and concentrated with a Pellicon 2 Mini tangential flow ultrafiltration system.Concentrated samples were then analyzed using fluorescence and SEC-HPLC. This CDOM optical study revealed the presence of two classes of compounds associated with the protein-like peak (peak T; excitation/emission (Ex/Em) maxima at around 280 nm/325 nm), which have very different chemical structures and ecological roles. In addition to proteins, we propose phenolic compounds as possible origins of peak T in coastal and wetland environments. In this study, natural water samples were obtained from subtropical rivers and estuarine environments within the Florida Coastal Everglades (FCE) ecosystem. The samples were ultra-filtered and excitation-emission fluorescence matrices (EEMs) were obtained. The EEMs showed the presence of four peaks with Ex/Em maxima at around 280 nm/325 nm (T), less than 260 nm/460 nm (A), 300 nm/412nm (M), and 350 nm/470 nm (C). To better understand the nature of peak T, the components originating this peak were separated using size exclusion chromatography (SEC) and detected by fluorescence emission at Ex/Em = 280 nm/325 nm. The elution curves revealed the presence of two elution peaks at a molecular weight of greater than 50K (void volume; T1) and around 7.6K (T2). This result suggested the need of cautious interpretation in the use of peak T as a proxy for the detection of proteinaceous materials in wetland and estuarine environments, since significant amounts of potentially interfering phenolic compounds are leached from senescent biomass in wetland and coastal ecosystems. As such EEM spectra of gallic acid an important component of hydrolysable tannins, and condensed tannins extracted from red mangroves (Rhizophora mangle) showed the presence of a peak maxima at a similar position to peak T (260/346 and 275/313 nm, respectively), suggesting these phenolic compounds can be possible sources of peak T. Geographic Coverage Study Extent Description The Study Extent of this dataset includes the FCE Shark River Slough, Taylor Slough, and Florida Bay research sites within Everglades National Park, South Florida Bounding Coordinates Geographic description: Samples were collected in the Taylor Slough and Shark River Slough, within Everglades National Park, South Florida. West bounding coordinate: -81.078 East bounding coordinate: -80.490 North bounding coordinate: 25.761 South bounding coordinate: 24.913 Geographic description: Florida Coastal Everglades LTER Study Area: South Florida, Everglades National Park, and Florida Bay West bounding coordinate: -81.078 East bounding coordinate: -80.490 North bounding coordinate: 25.761 South bounding coordinate: 24.913 FCE LTER Sites: SRS1a, SRS2, SRS3, SRS4, SRS5, SRS6, TS/Ph1a, TS/Ph2, TS/Ph3, TS/Ph4, TS/Ph5, TS/Ph6a, TS/Ph7a, TS/Ph8, TS/Ph9, TS/Ph10, TS/Ph11, and C-111. All Sites Geographic Description:FCE LTER Site SRS1a Longitude:-80.727 Latitude:25.761 Geographic Description:FCE LTER Site SRS2 Longitude:-80.785 Latitude:25.550 Geographic Description:FCE LTER Site SRS3 Longitude:-80.853 Latitude:25.468 Geographic Description:FCE LTER Site SRS4 Longitude:-80.964 Latitude:25.410 Geographic Description:FCE LTER Site SRS5 Longitude:-81.032 Latitude:25.377 Geographic Description:FCE LTER Site SRS6 Longitude:-81.078 Latitude:25.365 Geographic Description:FCE LTER Site TS/Ph1a Longitude:-80.59 Latitude:25.42 Geographic Description:FCE LTER Site TS/Ph2 Longitude:-80.61 Latitude:25.40 Geographic Description:FCE LTER Site TS/Ph3 Longitude:-80.66 Latitude:25.25 Geographic Description:FCE LTER Site TS/Ph4 Longitude:-80.52 Latitude:25.32 Geographic Description:FCE LTER Site TS/Ph5 Longitude:-80.52 Latitude:25.30 Geographic Description:FCE LTER Site TS/Ph6 Longitude:-80.65 Latitude:25.21 Geographic Description:FCE LTER Site TS/Ph7 Longitude:-80.64 Latitude:25.19 Geographic Description:FCE LTER Site TS/Ph8 Longitude:-80.53 Latitude:25.23 Geographic Description:FCE LTER Site TS/Ph9 Longitude:-80.49 Latitude:25.18 Geographic Description:FCE LTER Site TS/Ph10 Longitude:-80.68 Latitude:25.02 Geographic Description:FCE LTER Site TS/Ph11 Longitude:-80.94 Latitude:24.91 Geographic Description:C-111 Longitude:-80.52 Latitude:25.32 Temporal Coverage Start Date: 2002-03-01 End Date: 2003-10-01 Data Table Entity Name: ST_ND_Jaffe_006 Entity Description: Examination of protein-like fluorophores in chromophoric dissolved organic matter (CDOM) in a wetland and coastal environment Object Name: ST_ND_Jaffe_006 Data Format Number of Header Lines: 1 Attribute Orientation: column Field Delimiter: , Number of Records: Attributes Attribute Name: SITENAME Attribute Label: sitename Attribute Definition: Name of LTER site Storage Type: text Measurement Scale: Name of LTER site Missing Value Code: Attribute Name: Sampling Season Attribute Label: sampling season Attribute Definition: Collection season Storage Type: text Measurement Scale: Collection season Missing Value Code: Attribute Name: N/C Attribute Label: Nitrogen to carbon ratio Attribute Definition: Nitrogen to carbon ratio Storage Type: data Measurement Scale: Units: percent Precision: 0.001 Number Type: real Missing Value Code: -9999.000 (Value will never be recorded ) Attribute Name: T Attribute Label: Tryptophan Attribute Definition: Emission intensity of tryptophan peak Storage Type: data Measurement Scale: Units: QSUPerMilligramPerLiter Precision: 0.01 Number Type: real Missing Value Code: -9999.00 (Value will never be recorded ) Attribute Name: A1 Attribute Label: Fixed humic substance peak Attribute Definition: Excitation wavelength = 260nm and emission wavelength = 460 nm Storage Type: data Measurement Scale: Units: QSUPerMilligramPerLiter Precision: 0.01 Number Type: real Missing Value Code: -9999.00 (Value will never be recorded ) Attribute Name: A2 Attribute Label: UV humic peak Attribute Definition: Excitation wavelength = 260 nm, emission maximum Storage Type: data Measurement Scale: Units: QSUPerMilligramPerLiter Precision: 0.01 Number Type: real Missing Value Code: -9999.00 (Value will never be recorded ) Attribute Name: C Attribute Label: Visible humic peak Attribute Definition: Excitation wavelength = 350 nm, emission wavelength = 470 nm. Storage Type: data Measurement Scale: Units: QSUPerMilligramPerLiter Precision: 0.01 Number Type: real Missing Value Code: -9999.00 (Value will never be recorded ) Attribute Name: %T1 Attribute Label: Protein derived T1 Attribute Definition: Protein derived T1 Storage Type: data Measurement Scale: Units: QSUPerMilligramPerLiter Precision: 0.01 Number Type: real Missing Value Code: -9999.00 (Value will never be recorded ) Attribute Name: SEC_%T1 Attribute Label: SEC_%T1 Attribute Definition: Percentage of protein-like material (high molecular weight fraction) determined by size exclusion chromatography. Detector excitation wavelength = 280 nm, emission wavelength = 325 nm. Storage Type: data Measurement Scale: Units: percent Precision: 1 Number Type: real Missing Value Code: -9999 (Value will never be recorded ) Attribute Name: Max_WL Attribute Label: Maximum Wavelength Attribute Definition: Emission wavelength that gives maximum emission intensity at a fixed excitation of 313 nm Storage Type: data Measurement Scale: Units: nanometer Precision: 1 Number Type: real Missing Value Code: -9999 (Value will never be recorded ) Attribute Name: Max_I Attribute Label: Maximum Intensity Attribute Definition: Emission intensity of maximum emission wavelength at a fixed excitation of 313 nm. Storage Type: data Measurement Scale: Units: QSUPerMilligramPerLiter Precision: 0.1 Number Type: real Missing Value Code: -9999.0 (Value will never be recorded ) Attribute Name: FI Attribute Label: Fluorescence Index Attribute Definition: Ratio of emission intensities at 450 and 500 nm at a fixed excitation wavelength of 370 nm. Storage Type: data Measurement Scale: Units: dimensionless Precision: 0.01 Number Type: real Missing Value Code: -9999.00 (Value will never be recorded ) Attribute Name: %285 Attribute Label: %285 Attribute Definition: Obtained from synchronous fluorescence spectrum at a constant offset of 30 nm (excitation wavelengths = 285, 350, 385, 460 nm). Percentage of the first peak intensity (285 nm). Storage Type: data Measurement Scale: Units: percent Precision: 1 Number Type: real Missing Value Code: -9999 (Value will never be recorded ) Attribute Name: Peak_1 Attribute Label: Peak_1 Attribute Definition: Fluorescence intensity at an excitation of 285 nm in synchronous scan. Storage Type: data Measurement Scale: Units: QSUPerMilligramPerLiter Precision: 0.1 Number Type: real Missing Value Code: -9999.0 (Value will never be recorded ) Attribute Name: A_254 Attribute Label: Absorbance at 254 nm Attribute Definition: UV absorbance at 254 nm. Storage Type: data Measurement Scale: Units: dimensionless Precision: 0.001 Number Type: real Missing Value Code: -9999.000 (Value will never be recorded ) Methods Sampling Description Water samples were collected at the end of the dry and the wet season from all LTER sites, stored on ice and filtered through combusted GF/F glass fiber filters upon arrival to the lab. Method Step Description Natural water samples (16 to 50 L) were collected in Nalgene low density polyethylene carboys at the end of the dry (Mar-Apr) and the wet (Sep-Oct) season of 2002 and 2003 from all LTER sites. They were stored on ice and filtered through pre-combusted GF/F glass fiber filters upon arrival to the lab. The filtrate was processed through a tangential flow ultrafiltration system (TFF) equipped with 0.2um nominal molecular weight cutoff regenerated cellulose membranes, followed by a concentration with 1kDalton molecular weight cutoff membrane while samples were kept in iced water. Following the concentration procedure, the samples were diafiltered three times with 1-L of Milli-Q Water to eliminate salts. The concentrated UDOM samples were then freeze-dried and stored at room temperature in a dessicator. Before fluorescence or SEC-HPLC analysis, samples were re-hydrated with 0.05M Tris(hydroxymethl)aminomethane (THAM) (adjusted to pH at 7.0 with phosphoric acid) to a concentration of 20 mgCL-1 for Florida Bay samples (TS/Ph 9,10,and 11) and 5 mgCL-1 for all other samples.A series of emission fluorescence spectra of the samples were obtained at a ratio mode (emission signal-to-excitation lamp output) from lamda +10nm to lamda + 250nm at 1nm intervals, where lamda is the excitation wavelength. The excitation wavelength was scanned from 260 to 455 nm every 5 nm in a 1 cm quartz fluorescence cell at room temperature (20 degrees C). Fluorescence values were corrected for internal absorbance quenching following the procedures outlined in McKnight et al (2001). The Fluorescence spectra were also corrected for the internal instrument configuration using excitation and emission correction factors for the range of observations supplied by the manufacturer (e.g. Coble 1996; Kowalczuk et al. 2003). Fluorescence was reported as quinine sulfate units according to Maie et al. (2005). MilliQ-water was measured as the blank and subtracted from the sample spectra. UV-visible absorption spectra were measured with a UV-Vis scanning spectrophotometer using a 1 cm quartz cell. The molecular weight distribution of the UDOM was determined by size exclusion chromatography (SEC) (Maie et al. 2004; Scully et al. 2004). Analytical conditions were as follows: column, YMC-Pack Diol-120G (pore size 12 nm, I.D. 8.0mm x length 500mm), eluent, 0.05 M THAM (adjusted to pH at 7.0 with phosphoric acid); flow rate, 0.7 ml min-1; detection, fluorescence emission at 325 nm with an excitation at 280nm; injection volume, 200ul; temperature 22 degrees C. The void volume (VO; 13.8 min.) and void volume plus inner volume (VO+VI; 32.3 min.) were determined using Blue Dextran 2000 and tryptophan, respectively. The column was calibrated with several different dextran standards of know molecular weight. Total organic C and N content was measured on a Carlo Erba NA 1500 Nitrogen/Carbon Analyzer. Prior to analysis trace amounts of carbonate were removed by exposing the powered UDOM in a silver capsule to hydrochloric acid vapor for 4 hours (Hedges and Stern 1984). The samples were then dried under vacuum to eliminate any residual hydrochloric acid and sealed for later analysis. Citation Coble, Paula G 1996. Characterization of marine and terrestrial DOM in seawater using excitation-emission matrix spectroscopy. Marine Chemistry, 51: 325-346. Instrumentation Whatman GF/F glass fiber filters Nalgene polyethylene carboys Pellicon 2 Mini Flow Ultrafiltration System Jobin Yvon Horiba Fluoromax 3 Shimadzu 2101PC Spectrophotometer Carlo Erba NA 1500 Nitrogen/Carbon Analyzer (Carlo Erba Milan Italy). Method Step Description Natural water samples (16 to 50 L) were collected in Nalgene low density polyethylene carboys at the end of the dry (Mar-Apr) and the wet (Sep-Oct) season of 2002 and 2003 from all LTER sites. They were stored on ice and filtered through pre-combusted GF/F glass fiber filters upon arrival to the lab. The filtrate was processed through a tangential flow ultrafiltration system (TFF) equipped with 0.2um nominal molecular weight cutoff regenerated cellulose membranes, followed by a concentration with 1kDalton molecular weight cutoff membrane while samples were kept in iced water. Following the concentration procedure, the samples were diafiltered three times with 1-L of Milli-Q Water to eliminate salts. The concentrated UDOM samples were then freeze-dried and stored at room temperature in a dessicator. Before fluorescence or SEC-HPLC analysis, samples were re-hydrated with 0.05M Tris(hydroxymethl)aminomethane (THAM) (adjusted to pH at 7.0 with phosphoric acid) to a concentration of 20 mgCL-1 for Florida Bay samples (TS/Ph 9,10,and 11) and 5 mgCL-1 for all other samples.A series of emission fluorescence spectra of the samples were obtained at a ratio mode (emission signal-to-excitation lamp output) from lamda +10nm to lamda + 250nm at 1nm intervals, where lamda is the excitation wavelength. The excitation wavelength was scanned from 260 to 455 nm every 5 nm in a 1 cm quartz fluorescence cell at room temperature (20 degrees C). Fluorescence values were corrected for internal absorbance quenching following the procedures outlined in McKnight et al (2001). The Fluorescence spectra were also corrected for the internal instrument configuration using excitation and emission correction factors for the range of observations supplied by the manufacturer (e.g. Coble 1996; Kowalczuk et al. 2003). Fluorescence was reported as quinine sulfate units according to Maie et al. (2005). MilliQ-water was measured as the blank and subtracted from the sample spectra. UV-visible absorption spectra were measured with a UV-Vis scanning spectrophotometer using a 1 cm quartz cell. The molecular weight distribution of the UDOM was determined by size exclusion chromatography (SEC) (Maie et al. 2004; Scully et al. 2004). Analytical conditions were as follows: column, YMC-Pack Diol-120G (pore size 12 nm, I.D. 8.0mm x length 500mm), eluent, 0.05 M THAM (adjusted to pH at 7.0 with phosphoric acid); flow rate, 0.7 ml min-1; detection, fluorescence emission at 325 nm with an excitation at 280nm; injection volume, 200ul; temperature 22 degrees C. The void volume (VO; 13.8 min.) and void volume plus inner volume (VO+VI; 32.3 min.) were determined using Blue Dextran 2000 and tryptophan, respectively. The column was calibrated with several different dextran standards of know molecular weight. Total organic C and N content was measured on a Carlo Erba NA 1500 Nitrogen/Carbon Analyzer. Prior to analysis trace amounts of carbonate were removed by exposing the powered UDOM in a silver capsule to hydrochloric acid vapor for 4 hours (Hedges and Stern 1984). The samples were then dried under vacuum to eliminate any residual hydrochloric acid and sealed for later analysis. Citation Hedges, J I 1984. Carbon and nitrogen determinations of carbonate-containing solids. Limnology and Oceanography, 29: 657-663. Instrumentation Whatman GF/F glass fiber filters Nalgene polyethylene carboys Pellicon 2 Mini Flow Ultrafiltration System Jobin Yvon Horiba Fluoromax 3 Shimadzu 2101PC Spectrophotometer Carlo Erba NA 1500 Nitrogen/Carbon Analyzer (Carlo Erba Milan Italy). Method Step Description Natural water samples (16 to 50 L) were collected in Nalgene low density polyethylene carboys at the end of the dry (Mar-Apr) and the wet (Sep-Oct) season of 2002 and 2003 from all LTER sites. They were stored on ice and filtered through pre-combusted GF/F glass fiber filters upon arrival to the lab. The filtrate was processed through a tangential flow ultrafiltration system (TFF) equipped with 0.2um nominal molecular weight cutoff regenerated cellulose membranes, followed by a concentration with 1kDalton molecular weight cutoff membrane while samples were kept in iced water. Following the concentration procedure, the samples were diafiltered three times with 1-L of Milli-Q Water to eliminate salts. The concentrated UDOM samples were then freeze-dried and stored at room temperature in a dessicator. Before fluorescence or SEC-HPLC analysis, samples were re-hydrated with 0.05M Tris(hydroxymethl)aminomethane (THAM) (adjusted to pH at 7.0 with phosphoric acid) to a concentration of 20 mgCL-1 for Florida Bay samples (TS/Ph 9,10,and 11) and 5 mgCL-1 for all other samples.A series of emission fluorescence spectra of the samples were obtained at a ratio mode (emission signal-to-excitation lamp output) from lamda +10nm to lamda + 250nm at 1nm intervals, where lamda is the excitation wavelength. The excitation wavelength was scanned from 260 to 455 nm every 5 nm in a 1 cm quartz fluorescence cell at room temperature (20 degrees C). Fluorescence values were corrected for internal absorbance quenching following the procedures outlined in McKnight et al (2001). The Fluorescence spectra were also corrected for the internal instrument configuration using excitation and emission correction factors for the range of observations supplied by the manufacturer (e.g. Coble 1996; Kowalczuk et al. 2003). Fluorescence was reported as quinine sulfate units according to Maie et al. (2005). MilliQ-water was measured as the blank and subtracted from the sample spectra. UV-visible absorption spectra were measured with a UV-Vis scanning spectrophotometer using a 1 cm quartz cell. The molecular weight distribution of the UDOM was determined by size exclusion chromatography (SEC) (Maie et al. 2004; Scully et al. 2004). Analytical conditions were as follows: column, YMC-Pack Diol-120G (pore size 12 nm, I.D. 8.0mm x length 500mm), eluent, 0.05 M THAM (adjusted to pH at 7.0 with phosphoric acid); flow rate, 0.7 ml min-1; detection, fluorescence emission at 325 nm with an excitation at 280nm; injection volume, 200ul; temperature 22 degrees C. The void volume (VO; 13.8 min.) and void volume plus inner volume (VO+VI; 32.3 min.) were determined using Blue Dextran 2000 and tryptophan, respectively. The column was calibrated with several different dextran standards of know molecular weight. Total organic C and N content was measured on a Carlo Erba NA 1500 Nitrogen/Carbon Analyzer. Prior to analysis trace amounts of carbonate were removed by exposing the powered UDOM in a silver capsule to hydrochloric acid vapor for 4 hours (Hedges and Stern 1984). The samples were then dried under vacuum to eliminate any residual hydrochloric acid and sealed for later analysis. Citation Kowalczuk, P 2003. Characterization of CDOM in an organic-rich river and surrounding coastal ocean in the South Atlantic Bight. Aquatic Science, 65: 384-401. Instrumentation Whatman GF/F glass fiber filters Nalgene polyethylene carboys Pellicon 2 Mini Flow Ultrafiltration System Jobin Yvon Horiba Fluoromax 3 Shimadzu 2101PC Spectrophotometer Carlo Erba NA 1500 Nitrogen/Carbon Analyzer (Carlo Erba Milan Italy). Method Step Description Natural water samples (16 to 50 L) were collected in Nalgene low density polyethylene carboys at the end of the dry (Mar-Apr) and the wet (Sep-Oct) season of 2002 and 2003 from all LTER sites. They were stored on ice and filtered through pre-combusted GF/F glass fiber filters upon arrival to the lab. The filtrate was processed through a tangential flow ultrafiltration system (TFF) equipped with 0.2um nominal molecular weight cutoff regenerated cellulose membranes, followed by a concentration with 1kDalton molecular weight cutoff membrane while samples were kept in iced water. Following the concentration procedure, the samples were diafiltered three times with 1-L of Milli-Q Water to eliminate salts. The concentrated UDOM samples were then freeze-dried and stored at room temperature in a dessicator. Before fluorescence or SEC-HPLC analysis, samples were re-hydrated with 0.05M Tris(hydroxymethl)aminomethane (THAM) (adjusted to pH at 7.0 with phosphoric acid) to a concentration of 20 mgCL-1 for Florida Bay samples (TS/Ph 9,10,and 11) and 5 mgCL-1 for all other samples.A series of emission fluorescence spectra of the samples were obtained at a ratio mode (emission signal-to-excitation lamp output) from lamda +10nm to lamda + 250nm at 1nm intervals, where lamda is the excitation wavelength. The excitation wavelength was scanned from 260 to 455 nm every 5 nm in a 1 cm quartz fluorescence cell at room temperature (20 degrees C). Fluorescence values were corrected for internal absorbance quenching following the procedures outlined in McKnight et al (2001). The Fluorescence spectra were also corrected for the internal instrument configuration using excitation and emission correction factors for the range of observations supplied by the manufacturer (e.g. Coble 1996; Kowalczuk et al. 2003). Fluorescence was reported as quinine sulfate units according to Maie et al. (2005). MilliQ-water was measured as the blank and subtracted from the sample spectra. UV-visible absorption spectra were measured with a UV-Vis scanning spectrophotometer using a 1 cm quartz cell. The molecular weight distribution of the UDOM was determined by size exclusion chromatography (SEC) (Maie et al. 2004; Scully et al. 2004). Analytical conditions were as follows: column, YMC-Pack Diol-120G (pore size 12 nm, I.D. 8.0mm x length 500mm), eluent, 0.05 M THAM (adjusted to pH at 7.0 with phosphoric acid); flow rate, 0.7 ml min-1; detection, fluorescence emission at 325 nm with an excitation at 280nm; injection volume, 200ul; temperature 22 degrees C. The void volume (VO; 13.8 min.) and void volume plus inner volume (VO+VI; 32.3 min.) were determined using Blue Dextran 2000 and tryptophan, respectively. The column was calibrated with several different dextran standards of know molecular weight. Total organic C and N content was measured on a Carlo Erba NA 1500 Nitrogen/Carbon Analyzer. Prior to analysis trace amounts of carbonate were removed by exposing the powered UDOM in a silver capsule to hydrochloric acid vapor for 4 hours (Hedges and Stern 1984). The samples were then dried under vacuum to eliminate any residual hydrochloric acid and sealed for later analysis. Citation Maie, Nagamitsu 2004. Chemical characteristics and potential source of fulvic acids leached from the plow layer of paddy soil.. Geoderma, 120: 309-323. Instrumentation Whatman GF/F glass fiber filters Nalgene polyethylene carboys Pellicon 2 Mini Flow Ultrafiltration System Jobin Yvon Horiba Fluoromax 3 Shimadzu 2101PC Spectrophotometer Carlo Erba NA 1500 Nitrogen/Carbon Analyzer (Carlo Erba Milan Italy). Method Step Description Natural water samples (16 to 50 L) were collected in Nalgene low density polyethylene carboys at the end of the dry (Mar-Apr) and the wet (Sep-Oct) season of 2002 and 2003 from all LTER sites. They were stored on ice and filtered through pre-combusted GF/F glass fiber filters upon arrival to the lab. The filtrate was processed through a tangential flow ultrafiltration system (TFF) equipped with 0.2um nominal molecular weight cutoff regenerated cellulose membranes, followed by a concentration with 1kDalton molecular weight cutoff membrane while samples were kept in iced water. Following the concentration procedure, the samples were diafiltered three times with 1-L of Milli-Q Water to eliminate salts. The concentrated UDOM samples were then freeze-dried and stored at room temperature in a dessicator. Before fluorescence or SEC-HPLC analysis, samples were re-hydrated with 0.05M Tris(hydroxymethl)aminomethane (THAM) (adjusted to pH at 7.0 with phosphoric acid) to a concentration of 20 mgCL-1 for Florida Bay samples (TS/Ph 9,10,and 11) and 5 mgCL-1 for all other samples.A series of emission fluorescence spectra of the samples were obtained at a ratio mode (emission signal-to-excitation lamp output) from lamda +10nm to lamda + 250nm at 1nm intervals, where lamda is the excitation wavelength. The excitation wavelength was scanned from 260 to 455 nm every 5 nm in a 1 cm quartz fluorescence cell at room temperature (20 degrees C). Fluorescence values were corrected for internal absorbance quenching following the procedures outlined in McKnight et al (2001). The Fluorescence spectra were also corrected for the internal instrument configuration using excitation and emission correction factors for the range of observations supplied by the manufacturer (e.g. Coble 1996; Kowalczuk et al. 2003). Fluorescence was reported as quinine sulfate units according to Maie et al. (2005). MilliQ-water was measured as the blank and subtracted from the sample spectra. UV-visible absorption spectra were measured with a UV-Vis scanning spectrophotometer using a 1 cm quartz cell. The molecular weight distribution of the UDOM was determined by size exclusion chromatography (SEC) (Maie et al. 2004; Scully et al. 2004). Analytical conditions were as follows: column, YMC-Pack Diol-120G (pore size 12 nm, I.D. 8.0mm x length 500mm), eluent, 0.05 M THAM (adjusted to pH at 7.0 with phosphoric acid); flow rate, 0.7 ml min-1; detection, fluorescence emission at 325 nm with an excitation at 280nm; injection volume, 200ul; temperature 22 degrees C. The void volume (VO; 13.8 min.) and void volume plus inner volume (VO+VI; 32.3 min.) were determined using Blue Dextran 2000 and tryptophan, respectively. The column was calibrated with several different dextran standards of know molecular weight. Total organic C and N content was measured on a Carlo Erba NA 1500 Nitrogen/Carbon Analyzer. Prior to analysis trace amounts of carbonate were removed by exposing the powered UDOM in a silver capsule to hydrochloric acid vapor for 4 hours (Hedges and Stern 1984). The samples were then dried under vacuum to eliminate any residual hydrochloric acid and sealed for later analysis. Citation Maie, Nagamitsu 2005. Chemical characteristics of dissolved organic matter (DOM) in an extremely oligotrophic subtropical wetland.. Limnology and Oceanography, 50: 23-25. Instrumentation Whatman GF/F glass fiber filters Nalgene polyethylene carboys Pellicon 2 Mini Flow Ultrafiltration System Jobin Yvon Horiba Fluoromax 3 Shimadzu 2101PC Spectrophotometer Carlo Erba NA 1500 Nitrogen/Carbon Analyzer (Carlo Erba Milan Italy). Method Step Description Natural water samples (16 to 50 L) were collected in Nalgene low density polyethylene carboys at the end of the dry (Mar-Apr) and the wet (Sep-Oct) season of 2002 and 2003 from all LTER sites. They were stored on ice and filtered through pre-combusted GF/F glass fiber filters upon arrival to the lab. The filtrate was processed through a tangential flow ultrafiltration system (TFF) equipped with 0.2um nominal molecular weight cutoff regenerated cellulose membranes, followed by a concentration with 1kDalton molecular weight cutoff membrane while samples were kept in iced water. Following the concentration procedure, the samples were diafiltered three times with 1-L of Milli-Q Water to eliminate salts. The concentrated UDOM samples were then freeze-dried and stored at room temperature in a dessicator. Before fluorescence or SEC-HPLC analysis, samples were re-hydrated with 0.05M Tris(hydroxymethl)aminomethane (THAM) (adjusted to pH at 7.0 with phosphoric acid) to a concentration of 20 mgCL-1 for Florida Bay samples (TS/Ph 9,10,and 11) and 5 mgCL-1 for all other samples.A series of emission fluorescence spectra of the samples were obtained at a ratio mode (emission signal-to-excitation lamp output) from lamda +10nm to lamda + 250nm at 1nm intervals, where lamda is the excitation wavelength. The excitation wavelength was scanned from 260 to 455 nm every 5 nm in a 1 cm quartz fluorescence cell at room temperature (20 degrees C). Fluorescence values were corrected for internal absorbance quenching following the procedures outlined in McKnight et al (2001). The Fluorescence spectra were also corrected for the internal instrument configuration using excitation and emission correction factors for the range of observations supplied by the manufacturer (e.g. Coble 1996; Kowalczuk et al. 2003). Fluorescence was reported as quinine sulfate units according to Maie et al. (2005). MilliQ-water was measured as the blank and subtracted from the sample spectra. UV-visible absorption spectra were measured with a UV-Vis scanning spectrophotometer using a 1 cm quartz cell. The molecular weight distribution of the UDOM was determined by size exclusion chromatography (SEC) (Maie et al. 2004; Scully et al. 2004). Analytical conditions were as follows: column, YMC-Pack Diol-120G (pore size 12 nm, I.D. 8.0mm x length 500mm), eluent, 0.05 M THAM (adjusted to pH at 7.0 with phosphoric acid); flow rate, 0.7 ml min-1; detection, fluorescence emission at 325 nm with an excitation at 280nm; injection volume, 200ul; temperature 22 degrees C. The void volume (VO; 13.8 min.) and void volume plus inner volume (VO+VI; 32.3 min.) were determined using Blue Dextran 2000 and tryptophan, respectively. The column was calibrated with several different dextran standards of know molecular weight. Total organic C and N content was measured on a Carlo Erba NA 1500 Nitrogen/Carbon Analyzer. Prior to analysis trace amounts of carbonate were removed by exposing the powered UDOM in a silver capsule to hydrochloric acid vapor for 4 hours (Hedges and Stern 1984). The samples were then dried under vacuum to eliminate any residual hydrochloric acid and sealed for later analysis. Citation McKnight, D M 2001. Spectrofluorometric characterization of dissolved organic matter for the identification of percursor organic material and aromaticity.. Limnology and Oceanography, 46: 38-48. Instrumentation Whatman GF/F glass fiber filters Nalgene polyethylene carboys Pellicon 2 Mini Flow Ultrafiltration System Jobin Yvon Horiba Fluoromax 3 Shimadzu 2101PC Spectrophotometer Carlo Erba NA 1500 Nitrogen/Carbon Analyzer (Carlo Erba Milan Italy). Method Step Description Natural water samples (16 to 50 L) were collected in Nalgene low density polyethylene carboys at the end of the dry (Mar-Apr) and the wet (Sep-Oct) season of 2002 and 2003 from all LTER sites. They were stored on ice and filtered through pre-combusted GF/F glass fiber filters upon arrival to the lab. The filtrate was processed through a tangential flow ultrafiltration system (TFF) equipped with 0.2um nominal molecular weight cutoff regenerated cellulose membranes, followed by a concentration with 1kDalton molecular weight cutoff membrane while samples were kept in iced water. Following the concentration procedure, the samples were diafiltered three times with 1-L of Milli-Q Water to eliminate salts. The concentrated UDOM samples were then freeze-dried and stored at room temperature in a dessicator. Before fluorescence or SEC-HPLC analysis, samples were re-hydrated with 0.05M Tris(hydroxymethl)aminomethane (THAM) (adjusted to pH at 7.0 with phosphoric acid) to a concentration of 20 mgCL-1 for Florida Bay samples (TS/Ph 9,10,and 11) and 5 mgCL-1 for all other samples.A series of emission fluorescence spectra of the samples were obtained at a ratio mode (emission signal-to-excitation lamp output) from lamda +10nm to lamda + 250nm at 1nm intervals, where lamda is the excitation wavelength. The excitation wavelength was scanned from 260 to 455 nm every 5 nm in a 1 cm quartz fluorescence cell at room temperature (20 degrees C). Fluorescence values were corrected for internal absorbance quenching following the procedures outlined in McKnight et al (2001). The Fluorescence spectra were also corrected for the internal instrument configuration using excitation and emission correction factors for the range of observations supplied by the manufacturer (e.g. Coble 1996; Kowalczuk et al. 2003). Fluorescence was reported as quinine sulfate units according to Maie et al. (2005). MilliQ-water was measured as the blank and subtracted from the sample spectra. UV-visible absorption spectra were measured with a UV-Vis scanning spectrophotometer using a 1 cm quartz cell. The molecular weight distribution of the UDOM was determined by size exclusion chromatography (SEC) (Maie et al. 2004; Scully et al. 2004). Analytical conditions were as follows: column, YMC-Pack Diol-120G (pore size 12 nm, I.D. 8.0mm x length 500mm), eluent, 0.05 M THAM (adjusted to pH at 7.0 with phosphoric acid); flow rate, 0.7 ml min-1; detection, fluorescence emission at 325 nm with an excitation at 280nm; injection volume, 200ul; temperature 22 degrees C. The void volume (VO; 13.8 min.) and void volume plus inner volume (VO+VI; 32.3 min.) were determined using Blue Dextran 2000 and tryptophan, respectively. The column was calibrated with several different dextran standards of know molecular weight. Total organic C and N content was measured on a Carlo Erba NA 1500 Nitrogen/Carbon Analyzer. Prior to analysis trace amounts of carbonate were removed by exposing the powered UDOM in a silver capsule to hydrochloric acid vapor for 4 hours (Hedges and Stern 1984). The samples were then dried under vacuum to eliminate any residual hydrochloric acid and sealed for later analysis. Citation Scully, N M 2004. Early diagenesis of plant derived dissolved organic matter along a wetland, mangrove, estuary ecotone.. Limnology and Oceanography, 49: 1667-1678. Instrumentation Whatman GF/F glass fiber filters Nalgene polyethylene carboys Pellicon 2 Mini Flow Ultrafiltration System Jobin Yvon Horiba Fluoromax 3 Shimadzu 2101PC Spectrophotometer Carlo Erba NA 1500 Nitrogen/Carbon Analyzer (Carlo Erba Milan Italy). Quality Control Fluorescence measurements are corrected for internal absorbance quenching (McKnight et al., 2001). Fluorescence spectra are corrected for internal instrument configuration using excitation and emission correction factors (Coble, 1996 and Kowalczuk et al., 2003). SEC-HPLC results were corrected by calibrating the column with several different dextran standards of known molecular weight. Distribution Online distribution: http://fcelter.fiu.edu/perl/public_data_download.pl?datasetid=ST_ND_Jaffe_006.txt Intellectual Rights These data are classified as 'Type II' whereby original FCE LTER experimental data collected by individual FCE researchers to be released to restricted audiences according to terms specified by the owners of the data. Type II data are considered to be exceptional and should be rare in occurrence. The justification for exceptions must be well documented and approved by the lead PI and Site Data Manager. Some examples of Type II data restrictions may include: locations of rare or endangered species, data that are covered under prior licensing or copyright (e.g., SPOT satellite data), or covered by the Human Subjects Act, Student Dissertation data and those data related to the FCE LTER Program but not funded by the National Science Foundation (NSF) under LTER grants #DEB-9910514, and # DBI-0620409. Researchers that make use of Type II Data may be subject to additional restrictions to protect any applicable commercial or confidentiality interests. All publications based on this dataset must cite the data Contributor, the Florida Coastal Everglades Long-Term Ecological Research (LTER) Program and that this material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DEB-1237517, #DBI-0620409, and #DEB-9910514. Additionally, two copies of the manuscript must be submitted to the Florida Coastal Everglades LTER Program Office, LTER Program Manager, Florida International University, Southeast Environmental Research Center, OE 148, University Park, Miami, Florida 33199. For a complete description of the FCE LTER Data Access Policy and Data User Agreement, please go to FCE Data Management Policy at http://fcelter.fiu.edu/data/DataMgmt.pdf and LTER Network Data Access Policy at http://fcelter.fiu.edu/data/core/data_user_agreement/distribution_policy.html. Dataset Keywords FCE Florida Coastal Everglades LTER ecological research long-term monitoring Everglades National Park emissions Shark River Slough fluorescence water organisms seasonality organic matter wetlands nitrogen UDOM Fluorescence Optical measurements Fluorescence spectroscopy SEC-HPLC phenolic compounds Taylor Slough Data Submission Date: 2005-09-08 Maintenance This is now re-labelled as a short-term DOM dataset. This dataset replaces the original version named LT_ND_Jaffe_002. The FCE program is discontinuing its practice of versioning data as of March 2013. Dataset Contact Position: Information Manager Organization: LTER Network Office Address: UNM Biology Department, MSC03-2020 1 University of New Mexico Albuquerque, NM 87131-0001 USA Phone: 505 277-2535 Fax: 505 277-2541 Email: tech-support@lternet.edu URL: http://www.lternet.edu Position: Information Manager Organization: Florida Coastal Everglades LTER Program Address: Florida International University University Park OE 148 Miami, FL 33199 USA Phone: 305-348-6054 Fax: 305-348-4096 Email: fcelter@fiu.edu URL: http://fcelter.fiu.edu Dataset Submission Date 2005-09-08 Information Management Notes This is now re-labelled as a short-term DOM dataset. This dataset replaces the original version named LT_ND_Jaffe_001. The FCE program is discontinuing its practice of versioning data as of March 2013.