Table 2 Results of PLS1 calibration and prediction models for the quantitative compositional analysis of bamboo using pretreated visible–near infrared spectra
Pretreatment | Chemical composition | Factors | R2 c | RMSEC | R2 p | RMSEP | SD | RPD | RER |
|---|---|---|---|---|---|---|---|---|---|
MSC | Cellulose | 10 | 0.958 | 2.1 | 0.925 | 2.8 | 10.0 | 3.6 | 11.8 |
Xylan | 3 | 0.947 | 1.9 | 0.931 | 2.2 | 8.1 | 3.7 | 12.2 | |
Lignin | 8 | 0.972 | 1.5 | 0.939 | 2.2 | 8.8 | 4.1 | 13.3 | |
Glucose | 16 | 0.998 | 0.7 | 0.986 | 2.2 | 18.2 | 8.4 | 26.4 | |
Xylose | 14 | 0.998 | 1.3 | 0.974 | 3.8 | 23.7 | 6.3 | 17.5 | |
EMSC | Cellulose | 10 | 0.964 | 1.9 | 0.935 | 2.6 | 10.1 | 3.9 | 12.5 |
Xylan | 3 | 0.953 | 1.8 | 0.937 | 2.1 | 8.2 | 3.9 | 13.0 | |
Lignin | 7 | 0.964 | 1.7 | 0.943 | 2.1 | 8.7 | 4.2 | 13.3 | |
Glucose | 16 | 0.998 | 0.4 | 0.992 | 1.6 | 18.2 | 11.2 | 37.7 | |
Xylose | 14 | 0.998 | 1.1 | 0.980 | 3.3 | 23.7 | 7.3 | 20.5 | |
SNV | Cellulose | 5 | 0.910 | 3.0 | 0.874 | 3.6 | 9.8 | 2.7 | 7.9 |
Xylan | 4 | 0.955 | 1.8 | 0.935 | 2.1 | 8.2 | 3.9 | 13.3 | |
Lignin | 8 | 0.974 | 1.4 | 0.949 | 2.0 | 8.8 | 4.3 | 13.8 | |
Glucose | 15 | 0.996 | 1.1 | 0.974 | 2.9 | 18.2 | 6.3 | 21.0 | |
Xylose | 15 | 0.998 | 1.0 | 0.980 | 3.3 | 23.7 | 7.2 | 20.0 | |
First derivative | Cellulose | 8 | 0.994 | 0.8 | 0.990 | 1.0 | 10.2 | 10.1 | 35.2 |
Xylan | 7 | 0.990 | 0.8 | 0.982 | 1.1 | 8.3 | 7.7 | 25.2 | |
Lignin | 7 | 0.988 | 1.0 | 0.980 | 1.2 | 8.8 | 7.2 | 22.7 | |
Glucose | 9 | 0.998 | 0.6 | 0.996 | 1.1 | 18.2 | 16.1 | 52.6 | |
Xylose | 7 | 0.998 | 1.1 | 0.994 | 1.8 | 23.7 | 13.0 | 34.3 | |
Second derivative | Cellulose | 7 | 0.988 | 1.1 | 0.976 | 1.5 | 10.2 | 6.6 | 20.3 |
Xylan | 7 | 0.990 | 0.8 | 0.984 | 1.0 | 8.3 | 8.1 | 29.0 | |
Lignin | 10 | 0.996 | 0.5 | 0.994 | 0.7 | 8.9 | 13.7 | 36.6 | |
Glucose | 8 | 0.998 | 0.7 | 0.996 | 1.1 | 18.2 | 16.8 | 51.8 | |
Xylose | 7 | 0.996 | 1.4 | 0.992 | 2.0 | 23.7 | 11.7 | 32.5 |