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LBA-ECO CD-02 Leaf Water Potential, Forest and Pasture Sites, Para, Brazil: 2000-2001
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Revision date: June 28, 2012

Summary:

Data are reported for leaf water potential of leaves of seven species of trees and lianas from the primary forest at the km 67 Tower Site, Tapajos National Forest, and measurements of five sapling tree species and the grass Brachiaria brizantha from a pasture site located near the km 77 Pasture Tower Site, approximately 10 km from the primary forest site. The research area is situated within the Tapajos National Forest reserve, south of the city of Santarem, Para, Brazil. Measurements were made quarterly between March 2000 and March 2001. There is one comma-delimited data file with this data set.

Data Citation:

Cite this data set as follows:

Almeida, D.,T.F. Domingues, J. Ehleringer, L.A. Martinelli, C. Cook, L. Flanagan, J. Berry, and J.P. Ometto. 2012. LBA-ECO CD-02 Leaf Water Potential, Forest and Pasture Sites, Para, Brazil: 2000-2001. Data set. Available on-line [http://daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. http://dx.doi.org/10.3334/ORNLDAAC/1100

Implementation of the LBA Data and Publication Policy by Data Users:

The LBA Data and Publication Policy [http://daac.ornl.gov/LBA/lba_data_policy.html] is in effect for a period of five (5) years from the date of archiving and should be followed by data users who have obtained LBA data sets from the ORNL DAAC. Users who download LBA data in the five years after data have been archived must contact the investigators who collected the data, per provisions 6 and 7 in the Policy.

This data set was archived in July of 2012. Users who download the data between July 2012 and June 2017 must comply with the LBA Data and Publication Policy.

Data users should use the Investigator contact information in this document to communicate with the data provider. Alternatively, the LBA website [http://lba.inpa.gov.br/lba/] in Brazil will have current contact information.

Data users should use the Data Set Citation and other applicable references provided in this document to acknowledge use of the data.

Table of Contents:

1. Data Set Overview:

Project: LBA (Large-Scale Biosphere-Atmosphere Experiment in the Amazon)

Activity: LBA-ECO

LBA Science Component: Carbon Dynamics

Team ID: CD-02 (Ehleringer / Martinelli)

The investigators were Cook, Craig; Domingues, Tomas Ferreira; Ehleringer, James; Flanagan, Lawrence; Martinelli, Luiz Antonio; Ometto, Jean Pierre H.B.; Berry, Joseph and Almeida, Diane. You may contact Domingues, Tomas (tdomingu@staffmail.ed.ac.uk).

LBA Data Set Inventory ID: CD02_Leaf_Water_Potential

Data are reported for leaf water potential of leaves of seven species of trees and lianas from the primary forest at the km 67 Tower Site, Tapajos National Forest, and measurements of five sapling tree species and the grass Brachiaria brizantha from a pasture site located near the km 77 Pasture Tower Site, approximately 10 km from the primary forest site. The research area is situated within the Tapajos National Forest reserve, south of the city of Santarem, Para, Brazil. Measurements were made quarterly between March 2000 and March 2001.

2. Data Characteristics:

Data are presented in one comma-delimited ASCII file: CD02_Leaf_Water_Potential.csv.

Column Headingunits/formatDescription
1Site  Sampling location
2 DateyyyymmddSampling date (yyyymmdd)
3 Time  Sampling time: either predawn or midday
4 Vegetation Surrounding vegetation: either forest or pasture
5 Common_name Common name of the species sampled where known
6 Scientific_name Scientific name (genus species) of the species sampled where known
7 LWP_1MPa The 1st of 6 replicate measurements of leaf water potential made with a Scholender's pressure chamber, in mega Pascals (MPa)
8 LWP_2MPa The 2nd of 6 replicate measurements of leaf water potential made with a Scholender's pressure chamber, in mega Pascals (MPa)
9 LWP_3MPa The 3rd of 6 replicate measurements of leaf water potential made with a Scholender's pressure chamber, in mega Pascals (MPa)
10 LWP_4MPa The 4th of 6 replicate measurements of leaf water potential made with a Scholender's pressure chamber, in mega Pascals (MPa)
11 LWP_5MPa The 5th of 6 replicate measurements of leaf water potential made with a Scholender's pressure chamber, in mega Pascals (MPa)
12 LWP_6 MPa The 6th of 6 replicate measurements of leaf water potential made with a Scholender's pressure chamber, in mega Pascals (MPa)
13 Mean_LWP  Mean leaf water potential for the individual based on an average of the measurements made
14 St_dev_LWP  Standard deviation of the mean leaf water potential
Missing data are represented by -9999

Example data records:

Site,Date,Time,Vegetation,Common_name,Scientific_name,LWP_1,LWP_2,LWP_3,LWP_4,LWP_5,LWP_6,Mean_LWP,St_dev_LWP
STM km 67 tower,20000321,Predawn,forest,Breu,Protium sp.,-0.05,-0.05,-0.05,-9999,-9999,-9999,-0.05,0
STM km 67 tower,20000321,Predawn,forest,Caferana,Coussarea racemosa,-0.05,-0.05,-0.05,-9999,-9999,-9999,-0.05,0
...
STM km 67 tower,20001012,Predawn,forest,Breu,Protium sp.,-0.1,-0.2,-0.15,-9999,-9999,-9999,-0.15,0.05
STM km 67 tower,20001012,Predawn,forest,Caferana,Coussarea racemosa,-0.25,-0.2,-0.2,-9999,-9999,-9999,-0.22,0.03
...
STM km 77 tower,20010302,Midday,pasture,Shrub 7,Not identified,-0.2,-0.25,-0.25,-9999,-9999,-9999,-0.23,0.03
STM km 77 tower,20010302,Midday,pasture,Shrub 8,Not identified,-0.25,-0.25,-0.25,-9999,-9999,-9999,-0.25,0

Site boundaries: (All latitude and longitude given in decimal degrees)

Site (Region) Westernmost Longitude Easternmost Longitude Northernmost Latitude Southernmost Latitude Geodetic Datum
Para Western (Santarem) - km 67 Primary Forest Tower Site (Para Western (Santarem)) -54.95900 -54.95900-2.85700-2.85700 World Geodetic System, 1984 (WGS-84)
Para Western (Santarem) - km 77 Pasture Tower Site (Para Western (Santarem)) -54.88850 -54.88850       -3.02020  -3.02020 World Geodetic System, 1984 (WGS-84)

Time period

Platform/Sensor/Parameters measured include:

3. Data Application and Derivation:

These data, in combination with leaf level gas flux measurements, can be used to better understand ecophysiological parameters related to leaf level water and carbon fluxes, and the influence of wet and dry season on gas exchange parameters.

4. Quality Assessment:

Data have been checked and no further changes are anticipated.

5. Data Acquisition Materials and Methods:

Site description:

Measurements and leaf collections occurred at both undisturbed eastern Amazonian lowland tropical rain forest and pasture ecosystems, between March 2000 and March 2001, covering both wet and dry seasons. Edaphic and biological information about these sites were presented elsewhere (Silver et al., 2000, Vieira et al., 2004). The forest site was situated within the Tapajos National Forest reserve of the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA) located 67 km south of the city of Santarem, in the state of Para.  Annual precipitation averaged 2,097 mm per year between 1999 and 2003. From July through November that region usually experiences a five month dry season when precipitation averages less than 100 mm per month. Daily evapotranspiration averages 3.6 mm per day during the wet season and 4 mm per day during the dry season, while soil water content at a depth of 10 cm typically remained above 0.3 cm3 cm-3 (da Rocha et al. 2004). Air temperature above the canopy varies little throughout the year with maximum daily temperatures ranging between 24 and 32 degrees C and minimum daily temperatures ranging between 20 and 25 degrees C (Goulden et al., 2004).

The km 77 Pasture Tower Site site used in this study was located approximately 10 km from the primary forest site and is subject to similar regional climatic patterns. The pasture was characteristic of an old (ca. 13 years) cattle ranch farm planted with the C4 grass Brachiaria brizantha Stapf. and moderately colonized by saplings of forest species (Sakai et al., 2004).

Sampling of foliage:

Leaves of seven tree and liana species were collected pre-dawn and mid-day from the two 25 m walk-up towers adjacent to the eddy covariance tower at the site during four field trips spanning from the wet season of 2000 to the wet season of 2001.

At the pasture site, samples were collected from five sapling species and the grass Brachiaria brizantha during the wet and dry seasons of 2001.

Four to five leaves were collected from each individual and stored inside plastic bags containing wet paper towels, and then placed inside a cooler containing ice.

Leaf water potential measurements:

Analyses of leaf water potential were made within two hours after cutting the plant material. Six replicate measurements were made on each sample. Pre-dawn and mid-day leaf water potentials were measured with a Scholander pressure chamber (Plant Water Status Console, Model 3005-1422, Soil Moisture Corp., Goleta, CA).

Data Access:

This data is available through the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

Data Archive Center:

Contact for Data Center Access Information:
E-mail: uso@daac.ornl.gov
Telephone: +1 (865) 241-3952

7. References:

da Rocha, H.R., M.L. Goulden, S.D. Miller, M.C. Menton, L.D.V.O. Pinto, H.C. de Freitas and A.M. e S. Figueira. 2004. Seasonality of water and heat fluxes over a tropical forest in eastern Amazonia. Ecol. Appl. 14:22-32.

Goulden, M.L., S.D. Miller, H.R. da Rocha, M.C. Menton, H.C. de Freitas, A.M.E.S. Figueira, and C.A.D. de Sousa. 2004. Diel and seasonal patterns of tropical forest CO2 exchange. Ecological Applications 14(4):S42-55.

Sakai, R.K., D.R. Fitzjarrald, O.L.L. Moraes, R.M. Staebler, O.C. Acevedo, M.J. Czikowsky, R. Da Silva, E. Brait, and V. Miranda. 2004. Land-use change effects on local energy, water, and carbon balances in an Amazonian agricultural field. Global Change Biology 10(5):895-907.

Silver, W.L., J. Neff, M. McGroddy, E. Veldkamp, M. Keller, and R. Cosme. 2000. Effects of soil texture on belowground carbon and nutrient storage in a lowland Amazonian forest ecosystem. Ecosystems 3(2):193-209.

Vieira, S., P.B. de Camargo, D. Selhorst, R. Da Silva, L. Hutyra, J.Q. Chambers, I.F. Brown, N. Higuchi, J. dos Santos, S.C. Wofsy, S.E. Trumbore, and L.A. Martinelli. 2004. Forest structure and carbon dynamics in Amazonian tropical rain forests. Oecologia 140(3):468-479.