A Rapid Intelligent Screening of a Three-Band Index for Estimating Soil Copper Content
Abstract
1. Introduction
2. Materials and Methods
2.1. Research Area and Sampling Design
2.2. Soil Spectral Measurement
2.3. Feature Band Screening Method
2.4. Development of a Three-Band Spectral Index
2.5. Estimation Model Construction and Evaluation
3. Results
3.1. Analysis of Copper Concentration in Soil Samples
3.2. Statistical Analysis of Selected Feature Bands
3.3. Optimal Three-Band Spectral Index
3.4. Comparative Analysis of Models for Estimating Soil Copper Content
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Name of Spectral Index | Calculation Formula |
---|---|
TVI-1 | (S1 − S2)/S3 |
TVI-2 | (S2 + S3)/S1 |
TVI-3 | (S1 − S2)/(S3 − S2) |
Spectral Type | Screening Method | Number of Bands | Position of Bands (nm) |
---|---|---|---|
Original spectrum | CARS | 26 | 404.5, 674.5, 734.5, 774.5, 784.5, 824.5, 1164.5, 1194.5, 1204.5, 1214.5, 1224.5, 1264.5, 1274.5, 1417.5, 2155.5, 2165.5, 2175.5, 2185.5, 2215.5, 2225.5, 2305.5, 2315.5, 2325.5, 2335.5, 2345.5, 2395.5 |
Original spectrum | STE | 13 | 434.5, 444.5, 454.5, 464.5, 564.5, 604.5, 1014.5, 1034.5, 1094.5, 1194.5, 1214.5, 1294.5, 1417.5 |
First-order derivative spectrum | CARS | 12 | 434.5, 604.5, 804.5, 884.5, 914.5, 1024.5, 1447.5, 1647.5, 2155.5, 2235.5, 2275.5, 2365.5 |
First-order derivative spectrum | STE | 5 | 634.5, 724.5, 1024.5, 2305.5, 2365.5 |
Spectral Type | Screening Method | Spectral Index Type | Determination Coefficient R2 |
---|---|---|---|
Original spectrum | CARS | TVI-1 | 0.6093 |
Original spectrum | CARS | TVI-2 | 0.6087 |
Original spectrum | CARS | TVI-3 | 0.6209 |
Original spectrum | STE | TVI-1 | 0.3752 |
Original spectrum | STE | TVI-2 | 0.3915 |
Original spectrum | STE | TVI-3 | 0.5717 |
First-order derivative spectrum | CARS | TVI-1 | 0.7514 |
First-order derivative spectrum | CARS | TVI-2 | 0.7651 |
First-order derivative spectrum | CARS | TVI-3 | 0.5910 |
First-order derivative spectrum | STE | TVI-1 | 0.7592 |
First-order derivative spectrum | STE | TVI-2 | 0.7654 |
First-order derivative spectrum | STE | TVI-3 | 0.5257 |
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Liu, S.; Cui, S.; Wang, R.; Han, M.; Kou, J. A Rapid Intelligent Screening of a Three-Band Index for Estimating Soil Copper Content. Molecules 2025, 30, 3215. https://doi.org/10.3390/molecules30153215
Liu S, Cui S, Wang R, Han M, Kou J. A Rapid Intelligent Screening of a Three-Band Index for Estimating Soil Copper Content. Molecules. 2025; 30(15):3215. https://doi.org/10.3390/molecules30153215
Chicago/Turabian StyleLiu, Shiyao, Shichao Cui, Rengui Wang, Minming Han, and Jingtao Kou. 2025. "A Rapid Intelligent Screening of a Three-Band Index for Estimating Soil Copper Content" Molecules 30, no. 15: 3215. https://doi.org/10.3390/molecules30153215
APA StyleLiu, S., Cui, S., Wang, R., Han, M., & Kou, J. (2025). A Rapid Intelligent Screening of a Three-Band Index for Estimating Soil Copper Content. Molecules, 30(15), 3215. https://doi.org/10.3390/molecules30153215