Monitoring Soil Copper in Urban Land Using Visibale and Near-Infrared Spectroscopy with Spatially Nearby Samples
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Area and Sample Collection
2.2. Spectral Measurement and Chemical Analysis
2.3. Spatially Nearby Samples
2.4. Model Calibration
2.5. Model Performance
3. Results
3.1. Descriptive Statistics of Soil Samples
3.2. Estimation Performance of Cu Models without Considering Spatially Nearby Samples
3.3. Estimation Performance of Cu Models with Spatially Nearby Samples
4. Discussion
4.1. Estimation of Soil Cu Content in Urban Land by Vis-NIR Spectroscopy
4.2. The Influence of Spatially Nearby Samples on Soil Cu Estimation Model
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Sample | Number | Cu (mg·kg−1) | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Min | Max | Median | Mean | Std 1 | CV 2 | Skewness | Kurtosis | Background | Pollution Level | ||
Total | 250 | 20.45 | 103.24 | 59.44 | 58.29 | 15.57 | 0.27 | 0.13 | 0.12 | 17.00 | 36.00 |
Calibration | 200 | 20.45 | 103.24 | 59.44 | 58.29 | 15.60 | 0.27 | 0.13 | 0.15 | ||
Validation | 50 | 25.21 | 97.06 | 59.18 | 58.30 | 15.63 | 0.27 | 0.13 | 0.12 |
Number of Nearby Samples | Calibration | Validation | |||
---|---|---|---|---|---|
RMSEP | RPD | ||||
None | 0.64 | 9.72 | 0.75 | 8.56 | 1.83 |
20 | - | - | 0.75 | 7.75 | 2.01 |
50 | - | - | 0.90 | 4.90 | 3.14 |
100 | - | - | 0.92 | 4.56 | 3.43 |
150 | - | - | 0.93 | 4.00 | 3.90 |
200 | - | - | 0.92 | 4.34 | 3.60 |
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Liu, Y.; Shi, T.; Lan, Z.; Guo, K.; Yang, C.; Chen, Y. Monitoring Soil Copper in Urban Land Using Visibale and Near-Infrared Spectroscopy with Spatially Nearby Samples. Sensors 2024, 24, 5612. https://doi.org/10.3390/s24175612
Liu Y, Shi T, Lan Z, Guo K, Yang C, Chen Y. Monitoring Soil Copper in Urban Land Using Visibale and Near-Infrared Spectroscopy with Spatially Nearby Samples. Sensors. 2024; 24(17):5612. https://doi.org/10.3390/s24175612
Chicago/Turabian StyleLiu, Yi, Tiezhu Shi, Zeying Lan, Kai Guo, Chao Yang, and Yiyun Chen. 2024. "Monitoring Soil Copper in Urban Land Using Visibale and Near-Infrared Spectroscopy with Spatially Nearby Samples" Sensors 24, no. 17: 5612. https://doi.org/10.3390/s24175612