An Ensemble Modeling Framework for Distinguishing Nitrogen, Phosphorous and Potassium Deficiencies in Winter Oilseed Rape (Brassica napus L.) Using Hyperspectral Data
Abstract
:1. Introduction
2. Materials and Methods
2.1. Experiment Design
2.2. Data
2.3. Methodology
2.3.1. Framework Overview
2.3.2. Selecting Effective Spectral Bands
2.3.3. Composing New Features and Identifying Nutrient Deficiency
2.3.4. Evaluating the Performance of the Framework
3. Results
3.1. Leaf Nutrient Concentration and Canopy Spectra at Different Nutrient Fertilizer Levels
3.2. Selection of Spectral Bands
3.3. New Probability Features
3.4. Diagnosis of Nutrient Deficiency Levels
4. Discussion
4.1. Agreement of Band Selection With Known Spectral Features
4.1.1. Nitrogen
4.1.2. Phosphorous
4.1.3. Potassium
4.2. Diagnosis of Nutrient Deficiency Using Ensemble Modeling
5. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
Appendix A
Appendix A.1. Yield Response Curve
Appendix A.2. Soil Test
References
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Exp. | Season | Site | Planting Patterns | Cultivar | N, P, or K Fertilizer Rates (kg ha−1) | No. of Samples | References |
---|---|---|---|---|---|---|---|
Experiments of N Fertilization | |||||||
1 | 2015–2016 | Shayang | Transplanting | Huayouza No. 9 | 0, 90, 180, 270 | 43 | [35,36] |
2 | 2017–2018 | Wuhan | Transplanting | Huayouza No. 9 | 0, 75, 180 | 120 | None |
3 a | 2017–2018 | Wuxue-Guotan | Transplanting | Huayouza No. 9 | 0, 90, 180, 270 | 44 | None |
4 | 2018–2019 | Wuhan | Transplanting | Huayouza No. 9 | 0, 75, 180 | 122 | None |
5 a | 2018–2019 | Wuxue- Guotan | Transplanting | Huayouza No. 9 | 0, 90, 180, 270 | 53 | None |
6 | 2019–2020 | Wuxue- Guotan | Transplanting | Huayouza No. 9 | 90, 180, 270 | 45 | None |
Experiments of P Fertilization | |||||||
7 a | 2013–2014 | Wuxue-Guotan | Transplanting | Huayouza No. 9 | 0, 45, 90 | 9 | [35,36] |
8 | 2014–2015 | Wuhan | Direct sowing | Huayouza No. 62 | 0, 30, 90 | 180 | None |
9 a | 2017–2018 | Wuxue-Guotan | Transplanting | Huayouza No. 9 | 0, 45, 90, 135, 180 | 62 | None |
10 a | 2018–2019 | Wuxue-Guotan | Transplanting | Huayouza No. 9 | 0, 45, 90, 135, 180 | 35 | None |
Experiments of K Fertilization | |||||||
11 a | 2017–2018 | Wuxue-Guotan | Transplanting | Huayouza No. 9 | 0, 60, 120, 180, 240 | 89 | [37] |
12 | 2017–2018 | Wuxue-Congzhen | Transplanting | Huayouza No. 9 | 0, 75 | 18 | None |
13 a | 2018–2019 | Wuxue-Guotan | Transplanting | Huayouza No. 9 | 0, 60, 120, 180, 240 | 77 | None |
14 | 2018–2019 | Wuxue-Congzhen | Transplanting | Huayouza No. 9 | 0, 75 | 18 | None |
Site | pH | Organic Matter (g kg−1) | Total-N (g kg−1) | Olsen-P (mg kg−1) | Available-K (mg kg−1) | Available-B (mg kg−1) | Soil Texture | Classification |
---|---|---|---|---|---|---|---|---|
Shayang | 5.88 | 18.02 | 0.96 a | 11.79 a | 85.97 b | 0.39 b | Silt loam | Ultisols |
Wuhan | 6.15–6.38 | 19.08–20.27 | 1.07–1.15 b | 5.09–5.12 a | 166.8–207.74 b,c | 0.51–0.68 b | Silt loam | Ultisols |
Wuxue-Guotan | 5.73–5.96 | 25.2–36.53 | 1.54–2.19 b | 4.6–11.8 a | 36.25–81.8 a,b | 0.34–0.46 b | Sandy loam | Ultisols |
Wuxue-Congzhen | 5.05–6.2 | 21.8–31.76 | 1.75–2.18 b | 3.78–8.4 a | 25.1–58.9 a | 0.19–0.36 b | Sandy loam | Ultisols |
Nutrient | Severe | Medium | Normal | Excessive |
---|---|---|---|---|
N | 0 | 75, 90 | 180 | 270 |
P | 0 | 30, 45 | 90 | 135, 180 |
K | 0 | 60, 75 | 120 | 180, 240 |
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Liu, S.; Yang, X.; Guan, Q.; Lu, Z.; Lu, J. An Ensemble Modeling Framework for Distinguishing Nitrogen, Phosphorous and Potassium Deficiencies in Winter Oilseed Rape (Brassica napus L.) Using Hyperspectral Data. Remote Sens. 2020, 12, 4060. https://doi.org/10.3390/rs12244060
Liu S, Yang X, Guan Q, Lu Z, Lu J. An Ensemble Modeling Framework for Distinguishing Nitrogen, Phosphorous and Potassium Deficiencies in Winter Oilseed Rape (Brassica napus L.) Using Hyperspectral Data. Remote Sensing. 2020; 12(24):4060. https://doi.org/10.3390/rs12244060
Chicago/Turabian StyleLiu, Shishi, Xin Yang, Qingfeng Guan, Zhifeng Lu, and Jianwei Lu. 2020. "An Ensemble Modeling Framework for Distinguishing Nitrogen, Phosphorous and Potassium Deficiencies in Winter Oilseed Rape (Brassica napus L.) Using Hyperspectral Data" Remote Sensing 12, no. 24: 4060. https://doi.org/10.3390/rs12244060
APA StyleLiu, S., Yang, X., Guan, Q., Lu, Z., & Lu, J. (2020). An Ensemble Modeling Framework for Distinguishing Nitrogen, Phosphorous and Potassium Deficiencies in Winter Oilseed Rape (Brassica napus L.) Using Hyperspectral Data. Remote Sensing, 12(24), 4060. https://doi.org/10.3390/rs12244060