2007 ncera-180 annual meeting
DESCRIPTION
2007 NCERA-180 Annual Meeting. Veris NIR Spectrophotometer. www.veristech.com. Acquisition/Sampling Procedure. Map field NIRS at 10 cm level with Veris NIRS shank unit (15 m transects typical). PC compression and remove outliers. Fuzzy clustering into 15 clusters (use 3 PC’s). - PowerPoint PPT PresentationTRANSCRIPT
2007 NCERA-180 Annual Meeting
Veris NIR Spectrophotometer
www.veristech.com
Acquisition/Sampling Procedure
1) Map field NIRS at 10 cm level with Veris NIRS shank unit (15 m transects typical).
2) PC compression and remove outliers.
3) Fuzzy clustering into 15 clusters (use 3 PC’s).
4) Select 1 sample location per cluster (software).
5) Software guidance to sample locations.
• Lab-analyze soil carbon and bulk density (and other properties of interest).
• Calibrate NIRS data with lab analyses and validate. (Client responsible)
Calibration Procedure
IOWASet of 9 Iowa Fields (R^2 for leave 1 out cross-
validation)
00.10.20.30.40.50.60.70.80.9
property
coef
f. o
f d
eter
min
atio
n
(R^
2)
GEORGIA
KANSAS4 Kansas Fields: Avg R^2 without and with EC
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
carbon pH BpH-pH lime P K N
avg
R^
2
w/o EC
with EC
MONTANA
Lab results-Amino N
ILLINOIS: NIRS—Amino N
Goal: carbon inventory to 60 cm depth1. Map NIRS at 10 cm level with Veris NIRS shank unit.2. Use shank NIR (PCA, fuzzy c-means clustering) to identify 15
sample points for NIRS probe and soil cores.3. Collect NIRS data to 60 cm and 3” diameter soil cores (large
diameter to minimize probe effect on bulk density).4. Segment cores into 10 cm segments.5. Use probe NIRS (PCA, fuzzy c-means clustering) to identify
15 10 cm segments for lab analysis (each 10 cm level represented with at least two lab analyses).
6. Analyze soil carbon and bulk density in lab7. Calibrate NIRS data with lab analyses and cross-validate.
Carbon Sequestration Validation Problem: Soil carbon levels and rates of carbon change vary in the X, Y and –Z directions. This variability occurs at close spatial ranges within a field, and often exceeds the amount of newly sequestered carbon.
Grand Ave carbon inventory project—materials and methods
Acknowledgement
Funding for NIRS research provided by the Small Business Innovation Research programs
of the U.S. Departments of Agriculture and Energy