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Investigation:

CD-02 (Ehleringer / Martinelli)

LBA Dataset ID:

CD02_C_N_O

Originator(s):

1. EHLERINGER, J.R.
2. MARTINELLI, L.A.
3. OMETTO, J.P.H.B.
4. DOMINGUES, T.F.
      5. FLANAGAN, L.
6. BERRY, J.A.
7. COOK, C.
8. NARDOTO, G.B.

Point(s) of Contact:

ORNL DAAC User Services Office Oak Ridge National Laboratory Oak Ridge, Tennessee 37 (ornldaac@ornl.gov)

Dataset Abstract:

This data set reports the measurement of stable carbon, nitrogen, and oxygen isotope ratios in organic material (plant, litter and soil samples) in forest canopy profiles and pasture (grasses and shrubs) as well as corresponding carbon and nitrogen tissue concentrations in a number of different sites across Brazil. The sampling design captured the temporal variation in rainfall from 1999-2004. Carbon and nitrogen isotope ratios can act as a proxy for interpreting aspects of the carbon and nitrogen cycles in Amazonian rainforests. Data are in three comma-delimited ASCII files.

Beginning Date:

1999-03-01

Ending Date:

2004-08-31

Metadata Last Updated on:

2010-07-22

Data Status:

Archived

Access Constraints:

PUBLIC

Data Center URL:

http://daac.ornl.gov/

Distribution Contact(s):

ORNL DAAC User Services Office Oak Ridge National Laboratory Oak Ridge, Tennessee 37 (ornldaac@ornl.gov)

Access Instructions:

PUBLIC

Data Access:

IMPORTANT: The LBA-ECO Project website is no longer being supported. Links to external websites may be inactive. Final data products from the LBA project can be found at the ORNL DAAC. Please follow the fair use guidelines found in the dataset documentation when using or citing LBA data.
Datafile(s):

LBA-ECO CD-02 Carbon, Nitrogen, Oxygen Stable Isotopes in Organic Material, Brazil :  http://daac.ornl.gov/cgi-bin/dsviewer.pl?ds_id=983

Documentation/Other Supporting Documents:

LBA-ECO CD-02 Carbon, Nitrogen, Oxygen Stable Isotopes in Organic Material, Brazil :  http://daac.ornl.gov/LBA/guides/CD02_C_N_O_Organic.html

Citation Information - Other Details:

Ehleringer, J., L.A. Martinelli, J.P. Ometto, T.F. Domingues, L. Flanagan, J. Berry, C. Cook, and G.B. Nardoto. 2010. LBA-ECO CD-02 Carbon, Nitrogen, Oxygen Stable Isotopes in Organic Material, Brazil. Data set. Available on-line [http://daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. doi:10.3334/ORNLDAAC/983

Keywords - Theme:

Parameter Topic Term Source Sensor
LEAF CHARACTERISTICS BIOSPHERE VEGETATION LABORATORY AA (ATOMIC ABSORPTION SPECTROMETER)
STABLE ISOTOPES BIOSPHERE ECOLOGICAL DYNAMICS LABORATORY MASS SPECTROMETER

Uncontrolled Theme Keyword(s):  CARBON CONTENT, CARBON ISOTOPE, FOLIAR CA CONCENTRATION, FOLIAR P CONCENTRATION, NITROGEN CONTENT, NITROGEN ISOTOPE, STABLE ISOTOPE

Keywords - Place (with associated coordinates):

Region
(click to view profile)
Site
(click to view profile)
North South East West
  AMAZONAS (MANAUS) PARA WESTERN (SANTAREM) RONDONIA BRASILIA -10.42490 -10.42490 -58.75970 -58.75970

Related Publication(s):

Ehleringer, J.R., D.R. Bowling, L.B. Flanagan, J. Fessenden, B. Helliker, L.A. Martinelli, and J.P. Ometto. 2002. Stable isotopes and carbon cycle processes in forests and grasslands. Plant Biology 4(2):181-189.

Martinelli, L.A., J.P.H.B. Ometto, F.Y. Ishida, T.F. Domingues, G.B. Nardoto, R.S. Oliveira, and J.R. Ehleringer. 2007. The use of carbon and nitrogen stable isotopes to track effects of land-use changes in the Brazilian Amazon region. In: TE Dawson & RTW Siegwolf (Eds), Stable isotopes as indicators of ecological changes. Elsevier, San Francisco, EUA, p. 301-318.

Ometto, J.P.H., L.B. Flanagan, L.A. Martinelli, and J.R. Ehleringer. 2005. Oxygen isotope ratios of waters and respired CO2 in Amazonian forest and pasture ecosystems. Ecological Applications 15(1):58-70.

Ometto, J.P.H.B., J.R. Ehleringer, T.F. Domingues, J.A. Berry, F.Y. Ishida, E. Mazzi, N. Higuchi, L.B. Flanagan, G.B. Nardoto, and L.A. Martinelli. 2006. The stable carbon and nitrogen isotopic composition of vegetation in tropical forests of the Amazon Basin, Brazil. Biogeochemistry 79(1-2):251-274.

Ometto, J.P.H.B., L.B. Flanagan, L.A. Martinelli, M.Z. Moreira, N. Higuchi, and J.R. Ehleringer. 2002. Carbon isotope discrimination in forest and pasture ecosystems of the Amazon Basin, Brazil. Global Biogeochemical Cycles 16(4):1109, doi:10.1029/2001GB001462.

Data Characteristics (Entity and Attribute Overview):

Data Characteristics:

Data are in three comma-delimited ASCII files. In all files 9999 is used to signify missing data points.



File 1: LBA-ECO_CD02_Stable_Isotope_CNO_Organic_Matter.csv Contains stable isotope data on C, N and O from organic matter collected at LBA ECO focus regions in Amazonia, Para, and Rondonia between March 1999 and August 2004:

�Amazonas (Manaus), Sites: ZF2 - Transect E-W, ZF2 km 14, ZF3

�Para Western (Santarem), Sites: SECA Control, km 77, km 67, km 83, km 117, SECA Dry, Mojui

�Rondonia, Sites: Jaru Biological Reserve Tower A ( Rebio), Fazenda Nossa Senhora (Fz N Senhora)





Column Column Heading Units/format Description

Number

1 Region Sampling region

2 Site Sampling site

3 Latitude degrees Location in decimal degrees ( += N and - = S)

4 Longitude degrees Location in decimal degrees ( += E and - = W)

5 Ecosystem Vegetation forest or pasture

6 Description Information about the sample recorded in the field, may include; canopy position, life form, common name, scientific name, plot

7 Sample_type Values are leaves, litter, or soil8 Year YYYY Year of sample collection

9 Month MM Month of sample collection

10 Height meters Sampling height

11 Time HH:MM Sampling time 24 hour clock in local time which is UTC -4 for all sites and sampling dates

12 delta_15N parts per mil Isotopic ratio of 15N/14N in organic material referenced to N2, measured with continuous flow on Finigan Delta Plus at CENA measured with continuous flow on Finigan Delta Plus at CENA

13 delta_13C parts per mil Isotopic ratio of 13C/12C in organic material referenced to PDB, measured with continuous flow on Finigan Delta Plus at CENA

14 C % Carbon content referenced to working standard at CENA (Centro de Energia Nuclear na Agricultura at the University of Sao Paulo)

15 N % Nitrogen content referenced to working standard at CENA(Centro de Energia Nuclear na Agricultura at the University of Sao Paulo)

16 C_to_N Mass based ratio of carbon to nitrogen

17 delta_18O parts per mil Isotopic ratio of 18O/16O in cellulose referenced to SMOW,measured with continuous flow on Finigan Delta Plus at CENA

Example data records:



Region,Site,Latitude,Longitude,Ecosystem,Description,Sample_type,Year,Month,Height,Time,delta_15N,delta_13C,C,N,C_to_N,delta_18C

Manaus,ZF2 - Transect E-W,-2,-61,2500 m,Litter,1999,3,0,-999,4.3,-31.1,45.33,1.82,25.01,9999

Manaus,ZF2 - Transect E-W,-2,-61,2500 m,Litter,1999,3,0,-999,4.8,-32.6,43.54,1.21,36.21,9999

Manaus,ZF2 - Transect E-W,-2,-61,2500 m,Litter,1999,3,0,-999,4.3,-30.9,43.92,1.66,26.54,9999

...

Santarem,Mojui,-2.76667,-54.5792,Pasture,Shrub,Leaves,2002,10,0.5,14:30,6.9,-29.6,47.5,1.9,24.62,9999

Santarem,Mojui,-2.76667,-54.5792,Pasture,Shrub,Leaves,2002,10,0.5,14:33,8.1,-31.5,45.68,1.3,36.35,9999

...

Santarem,SECA Dry,-2.857,-54.959,Forest,Ucuubarana,2004,8,16,-999,6.2,-32.5,50.93,1.72,29.62,9999

Santarem,SECA Dry,-2.857,-54.959,Forest,Muirapiranga branca,Leaves,2004,8,20,-999,9.8,-31.5,41.008,1.97,20.9,9999

Santarem,SECA Dry,-2.857,-54.959,Forest,Quaruba branca,Leaves,2004,8,24,-999,5.4,-30.2,42.76,1.27,33.69,9999



File 2: LBA-ECO-CD02_Stable_Isotopes_CN_Leaf_tissue.csv Contains data on leaf tissue C and N concentrations as well as stable isotope values for both elements for foliage collected in and around the three eddy flux tower sites near Santarem Para between November 1999 and December 2003:



�Para Western (Santarem): km 67 Seca-Floresta (SECA Control) Site

�Para Western (Santarem): km 77 Pasture Tower Site

�Para Western (Santarem): km 67 Primary Forest Tower Site

�Para Western (Santarem): km 83 Logged Forest Tower Site

�Para Western (Santarem): Mojui



Column Column heading Units/format Description

number

1 Year YYYY Year of sample collection

2 Month MM Month of sample collection

3 Season Season (Dry or Wet)

4 Species Where identified: vegetation genus and species

5 Site Sampling site

6 Longitude Location in decimal degrees ( += E and - = W)

7 Latitude Location in decimal degrees ( += N and - = S)

8 Treatment Logged forest, primary forest or pasture

9 Height m Sampling height

10 Funct_group Functional group broadly defined as canopy position (Grass, Liana, Mid Canopy, Sapling, Top Canopy, Understory)

11 Obs Field observations

12 Leaf_area m^2 Leaf area in square meters

13 Leaf_dry g Weight after drying at 65 degrees C

14 SLA m^2 g^-1 Specific leaf area calculated as area/ mass

15 SLW g m^-2 Specific leaf weight calculated as mass/area

16 delta_15N per mil Isotopic ratio of 15N/14N, measured with continuous flow on Finigan Delta Plus at CENA

17 delta_13C per mil Isotopic ratio of 13C/12C referenced to PDB, measured with continuous flow on Finigan Delta Plus at CENA

18 C % Concentration of C in organic matter measured by combustion on an elemental analyzer at CENA

19 N % Concentration of N in organic matter measured by combustion on an elemental analyzer at CENA

20 C_to_N Mass based ratio of C to nitrogen

21 N_pool_mass g g^-1 Nitrogen pool per g leaf tissue

22 N_pool_area g m^-2 Nitrogen pool per m squared leaf area



Missing values are represented as 9999 (note this value is used rather than the more common -9999 due to the large number of negative values for delta variables)



Example data records:

Year,Month,Season,Species,Site,Longitude,Latitude,Treatment,Height,Funct-group,obs,Leaf_area,Leaf_dry,SLA,SLW,delta-15N,delta_13C,C,N,C_to_N,N_pool_mass,N_pool_area

1999,11,Dry,Brachiaria brizantha,km 77,-3.0202,-54.959,Pasture,9999,Grass,Light 1,9999,9999,9999,9999,3.3,-13.3,40.5,0.7,60.49,0.0007,9999

1999,11,Dry,Brachiaria brizantha,km 77,-3.0202,-54.959,Pasture,9999,Grass,Light 2,9999,9999,9999,9999,2.1,-12.9,37.4,1,39.34,0.01,9999

1999,11,Dry,Tachigalia myrmecophila,SECA Control,-2.857,-54.959,Primary Forest,27,Top Canopy,Light 1,0.007,9999,9999,9999,7,-29.5,49.3,3.4,14.34,0.034,9999

...

2001,3,Wet,Brachiaria brizantha,km 77,-3.0202,-54.959,Pasture,1,Grass,Light 1,0.0057,0.4166,0.014,72.51,3.44,-12.33,40.45,1.26,32.23,0.013,0.91

2001,3,Wet,Brachiaria brizantha,km 77,-3.0202,-54.959,Pasture,1,Grass,CO2 1,0.0067,0.4752,0.014,71.25,0.65,12.06,40.85,1.21,33.76,0.012,0.86

2001,3,Wet,Brachiaria brizantha,km 77,-3.0202,-54.959,Pasture,1,Grass,RH% 1,0.0044,0.2809,0.016,63.76,-0.15,-11.61,42.52,1.24,34.29,0.012,0.79

...

2003,12,Dry,Memora tanaeciicarpa,SECA Control,-2.857,-54.959,Primary Forest,27,Liana,light,0.0058,0.59,0.01,101.1,7.55,-29.64,43.44,2.46,17.66,0.025,2.49

2003,12,Dry,Memora tanaeciicarpa,SECA Control,-2.857,-54.959,Primary Forest,27,Liana,CO2,0.0056,0.519,0.011,93.07,7.26,-29.97,43.555,2.42,18.04,0.024,2.25

2003,12,Dry,Memora tanaeciicarpa,SECA Control,-2.857,-54.959,Primary Forest,27,Liana,RH,0.003,0.371,0.008,122.35,8.28,-29.19,43.69,2.23,19.59,0.022,2.73



File 3: LBA-ECO_CD02_Geographic_Variability_CN_Organic_Matter.csv

Contains C and N concentration and delta 13C and delta 15N as well as Ca and P concentrations for foliar tissue from five different study sites in the Amazon region:



�Santarem: Flona Site km 67

�Manaus: ZF2 Site km 34 - north-south transect (plateau and swale)

�Manaus: ZF2 Site km 25 - campinarana

�Sao Gabriel da Cachoeira: National Park of Pico da Neblina

�Brasilia: IBGE Reserve

In addition there are C and N concentrations and delta stable isotope values for wood and soil organic matter from the same 5 study sites. All data in this file was collected between January 2002 and October 2003.







Column Column heading Units/format Description

Number

1 Site Research site

2 Longitude degrees Location in decimal degrees ( += E and - = W)

3 Latitude degrees Location in decimal degrees ( += N and - = S)

4 Year YYYY Year of sample collection

5 Month MM Month of sample collection

6 Sample_type Sample type: Leaves, Litter or Soil

7 Family Vegetation family

8 Species Vegetation species from Manaus and Sao Gabriel identified by Carneiro and Pereira, INPA, Manaus, AM, Brazil

9 Legumes_non-legumes Species are classified as belonging to the Legume family or not

10 Soil_depth cm Soil depth in centimeters (cm)

11 Notes Field observations which may include a description of the vegetation type ( burned cerrado,unburned cerrado, or campiranha), topography (plateau or swale) or if the sample was collected from a liana or a location in the subcanopy

12 delta_13C per mil Isotopic ratio of 13C/12C in organic material referenced to PDB,measured with continuous flow on Finigan Delta Plus at CENA

13 C % Carbon content referenced to working standard at CENA

(Centro de Energia Nuclear na Agricultura at the University of Sao Paulo)

14 delta_15N per mil Isotopic ratio of 15N/14N in organic material referenced to N2,measured with continuous flow on Finigan Delta Plus at CENA

15 N % Nitrogen content referenced to working standard at CENA (Centro de Energia Nuclear na Agricultura at the University of Sao Paulo)

16 C_to_N Mass ratio of carbon to nitrogen

17 Ca g kg^-1 Calcium concentration determined by nitric acid digest and measured on an atomic absorption spectrophotometer at CENA

18 P g kg^-1 Phosphorus concentration determined by nitric acid digest method and measured on a spectrophotometer at CENA



Example data records:



Site,Longitude,Latitude,year,Month,Sample_type,Family,Species,Legumes_non-legumes,Soil_depth,Notes,delta_13C,C,delta_15N,N,C_to_N,Ca,P

km 67,-54.95,-2.85,2003,6,Leaves,Caesalpiniaceae,Chamaecrista xinguensis,Legumes,9999,None,-33.23,53.74,7.48,3.63,14.79,9999,9999

km 67,-54.95,-2.85,2003,6,Leaves,Caesalpiniaceae,Chamaecrista xinguensis,Legumes,9999,None,-33.79,47.21,7.74,3.21,14.71,9999,9999

km 67,-54.95,-2.85,2003,6,Leaves,Caesalpiniaceae,Chamaecrista xinguensis,Legumes,9999,None,-32.69,49.4,6.91,4.06,12.18,9999,9999

...

ZF2 km 34,-60,-2.5,2003,5,Leaves,Caesalpiniaceae,Batesia floribunda Spruce ex Benth.,Legumes,9999,plateau,-30.42,52.51,2.53,1.55,33.81,9999,9999

ZF2 km 34,-60,-2.5,2003,5,Leaves,Caesalpiniaceae,Batesia floribunda Spruce ex Benth.,Legumes,9999,plateau,-30.46,50.42,3.91,2.61,19.3,4.81,0.6

ZF2 km 34,-60,-2.5,2003,5,Leaves,Caesalpiniaceae,Batesia floribunda Spruce ex Benth.,Legumes,9999,plateau,-31.96,49.92,1.33,1.63,30.6,5.8,0.46

...

IBGE Reserve,-47.51,-15.15,2002,7,Soil,Not provided,Not provided,Not provided,20 to 30,unburned,-23.88,3.15,6.47,0.15,21.18,9999,9999

IBGE Reserve,-47.51,-15.15,2002,7,Soil,Not provided,Not provided,Not provided,30 to 40,unburned,-23.19,3.02,7.87,0.16,19.07,9999,9999

IBGE Reserve,-47.51,-15.15,2002,7,Soil,Not provided,Not provided,Not provided,40 to 50,unburned,-23.03,1.98,8.6,0.1,19.33,9999,9999

Data Application and Derivation:

Tropical forests play a central role in the global carbon cycle and improving our understanding of the factors that influence net carbon gain or loss in these ecosystems will improve our understanding of the global carbon cycle. Carbon isotope ratio analyses of plant materials can provide insight into carbon cycle dynamics by providing a quantitative assessment of stomatal limitations to photosynthesis (Farquhar et al. 1989, Ehleringer and Monson 1993) . Variations in the delta 13C of leaves in tropical forests are strongly correlated with position in the canopy profile with lighter foliar delta 13C (more negative) values found in the understory as compared to the canopy (Medina and Minchin 1980, Ehleringer et al. 1986). Variations in delta 13C values between sites may be driven by differences in forest stand structure and resulting effects on light availability and vapor pressure deficit.



Nitrogen isotope ratios provide information about N cycling within ecosystems (Hogberg 1990, Evans and Ehleringer 1993, Martinelli et al. 1999 and many more). Foliar and soil delta 15N patterns in tropical forests have been shown to be elevated relative to values in temperate forests (Martinelli et al. 1999). This pattern may be a result of gaseous N losses associated with microbial metabolism (Austin and Vitousek 1998) or the abundance of leguminous trees and their associated N fixing abilities in tropical forests.



Both N and C isotopes and the variability in delta values within and across sites may be used as a proxy for interpreting aspects of the C and N cycles in Amazonian rainforests.

Quality Assessment (Data Quality Attribute Accuracy Report):

Quality Assessment:

Stable isotope ratios of carbon and nitrogen were measured relative to international recognized standards. Internal working standards (Atropine and soil standard no. 502-308 from LECO Corporation) were included in every run, as regular laboratory procedure. The precision of measurements was plus or minus 0.3 %, 0.1 %, 0.25 per mil and 0.35 per mil for C, N, delta 13C and delta 15N, respectively. Precision for P and Ca analyzes were Ca (3%) and P (<1%).

Process Description:

Data Acquisition Materials and Methods:

Leaf samples were collected from plants along a height profile through the canopy at all sites during each study period. Three samples of leaf litter were randomly collected from each study site during each sample trip. All samples were oven-dried at 65 degrees C until constant weight and then ground to a fine powder. Soil samples were air-dried, sieved using a 2-mm mesh and homogenized. A smaller sub-sample was taken, handpicked to remove fine roots and other debris and then pounded. A 1.5-2 mg sub-sample of ground material or 15-20 mg sub-sample of pounded soil were placed and sealed in a tin capsule and loaded into a ThermoQuest-Finnigan Delta Plus isotope ratio mass spectrometer (Finnigan-MAT; CA, USA) in line with an Elemental Analyzer (Carla Erba model 1110; Milan, Italy) at the Laboratory of Isotope Ecology (CENA-USP, Brazil). From these analyzes we obtained both isotope ratio (delta 13C and delta 15N and in a limited number of cases delta 18O from cellulose) as well as tissue elemental content (C and N). Foliar Ca and P concentrations were determined after a tissue digestion with nitric acid + perchloric acid (5:1). P concentrations were determined using color spectrophotometry, Ca concentrations were determined using Atomic Absorption spectrophotometry with the addition of 0.25% Lanthanum oxide solution (to avoid Al interference).

References:

Austin, A and PM Vitousek. 1998. Nutrient dynamics on a precipitation gradient. Oecologia 113:519-529.



Ehleringer, JR et al. 1986. Leaf carbon isotope and mineral composition in subtropical plants along an irradiance cline. Oecologia 70: 520-526



Ehleringer, JR and RK Monson. 1993. Evolutionary and ecological aspects of photosynthetic pathway variation. Ann Rev. Ecol. Systemat. 24: 411-439.



Evans, RD and JR Ehleringer. 1993. A break in the nitrogen cycle in aridlands? Evidence from delta 13N of soils. Oecologia 94: 314-317



Farquhar, GD et al. 1989. Carbon isotope discrimination and photosynthesis. Ann. Rev. Plant Physiol. Plant Mol. Biol. 40: 503-537.



Hogberg, P. 1990. 15N natural abundance as a possible marker of the ectomycorrhizal habit of trees in mixed African woodlands. New Phytol. 115: 483-486.



Martinelli, LA et al. 1999. Nitrogen stable isotopic composition of leaves and soil: tropical vs. temperate forests. Biogeochemistry 46:45-65.



Medina, E. and P. Minchin. 1980. Stratification of delta 13C values of leaves in Amazonian rainforests. Oecologia 45: 355-378.



Related Publications



�Ometto, J.P.H.B., L.B. Flanagan, L.A. Martinelli, M.Z. Moreira, N. Higuchi, and J.R. Ehleringer. (2002) Carbon isotope discrimination in forest and pasture ecosystems of the Amazon Basin, Brazil. Global Biogeochemical Cycles 16(4):1109, doi:10.1029/2001GB001462.

�Ometto, J.P.H., L.B. Flanagan, L.A. Martinelli, and J.R. Ehleringer. (2005) Oxygen isotope ratios of waters and respired CO2 in Amazonian forest and pasture ecosystems. Ecological Applications 15(1):58-70.

�Ehleringer JR, Bowling DR, Flanagan L, Fessender J, Helliker B, Martinelli LA; Ometto JPHB (2002) Stable isotopes and carbon cycle in forests and grasslands. Plant Biology, 4: 181-189

�Ometto, J.P.H.B., J.R. Ehleringer, T.F. Domingues, J.A. Berry, F.Y. Ishida, E. Mazzi, N. Higuchi, L.B. Flanagan, G.B. Nardoto, and L.A. Martinelli. 2006. The stable carbon and nitrogen isotopic composition of vegetation in tropical forests of the Amazon Basin, Brazil. Biogeochemistry 79(1-2):251-274.

�Martinelli LA, Ometto JPHB, Ishida FY, Domingues TF, Nardoto GB, Oliveira RS, Ehleringer JR. The use of carbon and nitrogen stable isotopes to track effects of land-use changes in the Brazilian Amazon region. In: TE Dawson & RTW Siegwolf (Eds), Stable isotopes as indicators of ecological changes. Elsevier, San Francisco, EUA, p. 301-318, 2007

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