Table
|
Column
|
Fieldname
|
Description
|
Soil
Lab Data |
1
|
Batch
|
Batch
number that a soil or plant sample is allocated to by the ICRAF Soil
Laboratory. |
Soil
Lab Data |
2
|
Labid
|
Laboratory
ID code allocated to a soil or plant sample by the ICRAF Soil Laboratory. Both
the Batch and Labid are required to uniquely identify a sample. This combination
of codes is used to match soil and plant analytical data produced by the
laboratory with the reflectance spectra. |
Soil
Lab Data |
3
|
ph
|
Soil
pH. 1:2.5 soil:solution ratio. |
Soil
Lab Data |
4
|
exa
|
Exchangeable
acidity (cmolc kg-1). Extraction with 1M KCl using a 1:10
soil:solution ratio, analyzed by NaOH titration. Samples with pH>=5.5 were
assumed to have zero exchangeable acidity. |
Soil
Lab Data |
5
|
exca
|
Exchangeable
Ca (cmolc kg-1). Extraction with 1M KCl using a 1:10
soil:solution ratio, analyzed by atomic absorption spectrometry.
|
Soil
Lab Data |
6
|
exmg
|
Exchangeable
Mg (cmolc kg-1). Extraction with 1M KCl using a 1:10
soil:solution ratio, analyzed by atomic absorption spectrometry.
|
Soil
Lab Data |
7
|
exna
|
Exchangeable
Na (cmolc kg-1). Extraction with 1M KCl using a 1:10
soil:solution ratio, analyzed by flame photometry. Samples with pH <7.5 were
assumed to have zero exchangeable Na. |
Soil
Lab Data |
8
|
exk
|
Exchangeable
K (cmolc kg-1). Extraction with 0.5M NaHCO3 +
0.01M EDTA (pH 8.5, modified Olsen) using a 1:10 soil:solution ratio and
analyzed by flame photometer. |
Soil
Lab Data |
9
|
exp
|
Exchangeable
P (mg kg-1). Extraction with 0.5M NaHCO3 + 0.01M EDTA (pH 8.5,
modified Olsen) using a 1:10 soil:solution ratio and analyzed colorimetrically
(molybdenum blue). |
Soil
Lab Data |
10
|
soc
|
Organic
C (g kg-1). Determined colorimetrically after H2SO4–dichromate
oxidation at 150°C. |
Soil
Lab Data |
11
|
clay
|
Clay
content (g kg-1). Particle size distribution was determined using the
hydrometer method after pre-treatment with H2O2 to remove organic matter
|
Soil
Lab Data |
12
|
sand
|
Sand
content (g kg-1). Particle size distribution was determined using the
hydrometer method after pre-treatment with H2O2 to remove organic matter
|
Soil
Lab Data |
13
|
silt
|
Silt
content (g kg-1). Particle size distribution was determined using the
hydrometer method after pre-treatment with H2O2 to remove organic matter
|
Soil
Lab Data |
14
|
amn
|
N
mineralization potential (mg kg-1 d-1) was determined by
determination of ammonium production with 7-d anaerobic incubations at 40°C
|
Soil
Lab Data |
15
|
exbas
|
Exchangeable
bases (cmolc kg-1.) Calculated as the sum of exchangeable Ca, Mg, Na,
and K, |
Soil
Lab Data |
16
|
ecec
|
Effective
cation exchange capacity (cmolc kg-1.) Calculated as the sum of
exchangeable acidity and exchangeable bases. |
Soil
Lab Data |
17
|
ececlay
|
Effective
cation exchange capacity per unit clay (cmolc kg-1 clay) calculated
as effective cation exchange capacity divided by the clay fraction.
|
Spectral
Codes |
1
|
Study
|
Code
denoting the research study with which the spectra are associated. See "Studies"
table for description of study codes. |
Spectral
Codes |
2
|
Batch
|
Batch
number that a soil or plant sample is allocated to by the ICRAF Soil
Laboratory. |
Spectral
Codes |
3
|
Labid
|
Laboratory
ID code allocated to a soil or plant sample by the ICRAF Soil Laboratory. Both
the Batch and Labid are required to uniquely identify a sample. This combination
of codes is used to match soil and plant analytical data produced by the
laboratory with the reflectance spectra. |
Spectral
Codes |
4
|
Material
|
Material
type scanned. Soil = soil samples; Sediment = sediment samples; Plant = plant
samples; Rock = rock or mineral samples; Manmade = manmade samples; S_Card =
internal standard (brown coloured card); S_Mylar = internal standard (Mylar
two-way reflectance); S_Soil = internal soil standard 1; S_Soil2 = internal soil
standard 2. [Further details of materials are described in the Treatment
field] |
Spectral
Codes |
5
|
Spectrum#
|
Spectrum
code given when saving the original spectra on the spectrometer. It is used for
matching the Spectral Data to the Spectral Codes tables.
|
Spectral
Codes |
6
|
Spectralon
|
White
reference code issued by Labsphere for calibrated Spectralon. This code can be
used to match spectra with the white reference calibration spectrum to correct
relative reflectance to US National Laboratory Traceable Standard SRS-99-020-M99
(MIST). |
Spectral
Codes |
7
|
Site
|
Name
of geographic location of sample. |
Spectral
Codes |
8
|
Plot_Code
|
Plot
code used for matching samples to georeferencing and other field data in
landscape level studies. |
Spectral
Codes |
9
|
Gradsect
|
Gradient-directed
transect number (generally directed down steepest slope) used in landscape level
studies. |
Spectral
Codes |
10
|
Position
|
Position
(in metres) of exact sample location within a plot or gradsect (generally
directed down steepest slope from plot edge or start of transect).
|
Spectral
Codes |
11
|
Plot
|
Plot
code used in field experiments (study specific).
|
Spectral
Codes |
12
|
Block
|
Block
code used in field experiments (study specific).
|
Spectral
Codes |
13
|
Treatment
|
Treatment
code used in field experiments (study specific) or sample description.
|
Spectral
Codes |
14
|
Depth
Code |
Sequential
numbering of soil depth layers sampled from surface layer downwards (study
specific). |
Spectral
Codes |
15
|
Depth
|
Soil
depth range sampled (metres). |
Spectral
Codes |
16
|
Replicate
|
Replicate
number for dishes of the same material sample scanned by the spectrometer.
|
Spectral
Codes |
17
|
Rotation
|
Rotation
number where the same dish of the same sample is scanned by the spectrometer,
rotated through 90 degrees on each successive rotation.
|
Spectral
Codes |
18
|
Region
|
ICRAF
region from which sample was collected (Eastern Africa, Southern Africa, Western
Africa, SE Asia, Latin America). |
Spectral
Codes |
19
|
Country
|
Country
from which sample was collected. |
Spectral
Codes |
20
|
Optics
|
Optical
set up used for reflectance readings. Lamp = raw fibreoptic from above
illuminated with Lowell lamps (Shepherd & Walsh, 2000); torch =
viewed from below using a high intensity reflectance probe, through Duran
glass petri dishes; torch_B = torch plus black background plate; mug = viewed
from below using a high intensity source probe, through Duran glass petri
dishes; mug_B = mug probe plus black background plate; outdoors = solar
illumination |
Spectral
Codes |
21
|
Calibration
|
Instrument
calibration number issued by Analytical Spectral Devices after each
recalibration/service. |
Spectral
Data |
1
|
Spectrum#
|
Spectrum
code given when saving the original spectra on the spectrometer. It is used for
matching the Spectral Data to the Spectral Codes tables.
|
Spectral
Data |
2
|
W350_W2500
|
Relative
reflectance in each waveband from 350 nm to 2500 nm at 10 nm intervals (216
wavebands). |