Analysis of Nitrogen Uptake in Winter Wheat Using Sensor and Satellite Data for Site-Specific Fertilization
Abstract
:1. Introduction
2. Materials and Methods
2.1. Site and Weather Conditions
2.2. Crop Management
2.3. Experimental Design
2.4. Methods of Determining Nitrogen Uptake
2.5. Data Processing
2.6. Descriptive Statistics
2.7. Correlation Analysis
3. Results
3.1. Spatial Variation in Nitrogen Uptake in 2020 (Field A)
3.2. Spatial Variation in Nitrogen Uptake in 2021 (Field B)
3.3. Correlation between Variables
3.3.1. Field A (2020)
3.3.2. Field B (2021)
4. Discussion
4.1. Discussion of the Methods
4.1.1. Site Selection
4.1.2. Ground Truth Data
4.2. Discussion of the Results
4.2.1. Sensor Data
4.2.2. Satellite Data
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Property | Unit | Field A | Field B |
---|---|---|---|
Soil classification | Cambisol | Cambisol | |
Soil type | Silty loam | Silty loam | |
Soil fertility index * | 75–85 | 70–80 | |
Sand (0–30 cm) | % | 6.0 | 6.9 |
Silt (0–30 cm) | % | 70.1 | 69.4 |
Clay (0–30 cm) | % | 23.9 | 23.7 |
Available water capacity (in 10 cm) | Vol.% | 24.0 | 23.2 |
Soil organic carbon content (0–30 cm) | % DM | 1.2 | 1.4 |
Soil total nitrogen content (0–30 cm) | % DM | 0.14 | 0.12 |
Plant available phosphorus content (0–30 cm) | mg (100 g)−1 | 14.8 | 17.9 |
Plant available potassium content (0–30 cm) | mg (100 g)−1 | 17.7 | 18.4 |
pH (0–30 cm) | 6.5 | 6.9 |
Unit | January to March | April to June | July to September | October to December | Year | |
---|---|---|---|---|---|---|
2000–2020 Makofen | ||||||
°C | 1.4 | 14.4 | 17.3 | 4.7 | 9.5 | |
Precipitation ∑ | mm | 170 | 209 | 230 | 172 | 781 |
2020 Makofen | ||||||
°C | 3.7 | 13.9 | 18.3 | 5.1 | 10.3 | |
Precipitation ∑ | mm | 149 | 189 | 176 | 141 | 655 |
2021 Makofen | ||||||
°C | 1.8 | 13.1 | 17.3 | 4.4 | 9.2 | |
Precipitation ∑ | mm | 129 | 268 | 250 | 165 | 812 |
Field | Treatment | Unit | Amount | Product | Date |
---|---|---|---|---|---|
A | Sowing | kg/ha−1 | 156 | Meister | 27 October 2019 |
A | First N fertilization | kg/ha−1 | 60 | ASN | 28 March 2020 |
A | Second N fertilization | kg/ha−1 | 80 | CAN | 30 April 2020 |
A | Third N fertilization | kg/ha−1 | 40 | CAN | 20 May 2020 |
A | N fertilization, total | kg/ha−1 | 180 | ||
A | Plant protection | kg/ha−1 | 0.05/0.07 | Biathlon, Concert | 7 April 2020 |
A | Plant protection | L/ha−1 | 0.5 | CCC 720 | 7 April 2020 |
A | Plant protection | L/ha−1 | 1.25/0.075 | Capalo/Karate | 16 May 2020 |
A | Plant protection | L/ha−1 | 2.0 | Osiris | 13 June 2020 |
B | Sowing | kg/ha−1 | 205 | Meister | 10 November 2020 |
B | First N fertilization | kg/ha−1 | 78 | ASN | 4 March 2021 |
B | Second N fertilization | kg/ha−1 | 54 | CAN | 8 May 2021 |
B | Third N fertilization | kg/ha−1 | 40 | CAN | 4 June 2021 |
B | N fertilization, total | kg/ha−1 | 172 | ||
B | Plant protection | kg/ha−1 | 0.13 | Broadway | 22 April 2021 |
B | Plant protection | L/ha−1 | 0.25/0.5 | Pixxaro/CCC 720 | 22 April 2021 |
B | Plant protection | L/ha−1 | 1.0/0.3 | Revystar/Flexity | 20 May 2021 |
B | Plant protection | L/ha−1 | 1.0/0.075 | Ascra Xpro/Karate | 11 June 2021 |
Variable | n | Year | BBCH | Unit | Mean | Median | Minimum | Maximum | Standard Deviation | Skewness |
---|---|---|---|---|---|---|---|---|---|---|
Biomass samples | 30 | 2020 | 31 | kg N ha−1 | 50.2 | 50.9 | 33.2 | 64.1 | 7.9 | −0.41 |
Satellite data | 30 | 2020 | 31 | kg N ha−1 | 30.4 | 30.7 | 23.3 | 35.8 | 3.4 | −0.36 |
Sensor data | 30 | 2020 | 31 | kg N ha−1 | 42.7 | 43.7 | 24.6 | 66.2 | 9.8 | 0.28 |
Biomass samples | 30 | 2020 | 39 | kg N ha−1 | 118.2 | 118.4 | 109.2 | 125.2 | 3.7 | −0.34 |
Satellite data | 30 | 2020 | 39 | kg N ha−1 | 116.9 | 122.7 | 84.9 | 141.6 | 17.2 | −0.51 |
Sensor data | 30 | 2020 | 39 | kg N ha−1 | 124.1 | 127.1 | 68.8 | 169.1 | 27.2 | −0.37 |
Biomass samples | 30 | 2020 | 55 | kg N ha−1 | 186.8 | 187.9 | 167.1 | 199.5 | 9.6 | −0.45 |
Satellite data | 30 | 2020 | 55 | kg N ha−1 | 144.9 | 145.4 | 121.6 | 163.0 | 11.9 | −0.34 |
Sensor data | 30 | 2020 | 55 | kg N ha−1 | 203.6 | 216.1 | 143.5 | 247.3 | 32.2 | −0.52 |
Biomass samples | 30 | 2020 | 65 | kg N ha−1 | 225.5 | 225.9 | 211.8 | 235.2 | 6.1 | −0.37 |
Satellite data | 30 | 2020 | 65 | kg N ha−1 | 178.1 | 181.2 | 164.1 | 188.3 | 7.9 | −0.57 |
Sensor data | 30 | 2020 | 65 | kg N ha−1 | 248.5 | 255.3 | 166.9 | 320.2 | 37.9 | −0.30 |
Biomass samples | 45 | 2021 | 31 | kg N ha−1 | 45.2 | 44.9 | 29.4 | 63.0 | 7.5 | 0.12 |
Satellite data | 45 | 2021 | 31 | kg N ha−1 | 40.8 | 40.5 | 33.8 | 47.6 | 1.9 | −0.11 |
Sensor data | 45 | 2021 | 31 | kg N ha−1 | 43.9 | 44.9 | 23.5 | 62.1 | 9.7 | −0.34 |
Biomass samples | 45 | 2021 | 39 | kg N ha−1 | 144.3 | 142.2 | 124.1 | 195.8 | 13.9 | 1.17 |
Satellite data | 45 | 2021 | 39 | kg N ha−1 | 123.4 | 120.4 | 100.8 | 161.0 | 16.0 | 0.9 |
Sensor data | 45 | 2021 | 39 | kg N ha−1 | 143.0 | 133.7 | 103.8 | 217.5 | 31.2 | 0.51 |
Biomass samples | 45 | 2021 | 55 | kg N ha−1 | 192.3 | 192.1 | 142.6 | 225.9 | 16.1 | −0.74 |
Satellite data | 45 | 2021 | 55 | kg N ha−1 | 170.0 | 169.2 | 146.4 | 202.8 | 12.5 | 0.47 |
Sensor data | 45 | 2021 | 55 | kg N ha−1 | 199.9 | 191.6 | 118.3 | 275.7 | 44.1 | 0.24 |
Biomass samples | 45 | 2021 | 65 | kg N ha−1 | 218.3 | 217.5 | 182.4 | 260.8 | 17.5 | 0.52 |
Satellite data | 45 | 2021 | 65 | kg N ha−1 | 183.4 | 182.6 | 140.8 | 225.5 | 21.4 | 0.19 |
Sensor data | 45 | 2021 | 65 | kg N ha−1 | 232.1 | 239.3 | 147.2 | 308.5 | 46.9 | 0.11 |
R2 | BBCH | Sensor 2020 | Satellite 2020 | Sensor 2021 | Satellite 2021 |
---|---|---|---|---|---|
Biomass samples 2020 | 31 | 0.74 | 0.60 | ||
Biomass samples 2020 | 39 | 0.83 | 0.80 | ||
Biomass samples 2020 | 55 | 0.77 | 0.74 | ||
Biomass samples 2020 | 65 | 0.67 | 0.67 | ||
Biomass samples 2021 | 31 | 0.66 | 0.48 | ||
Biomass samples 2021 | 39 | 0.76 | 0.57 | ||
Biomass samples 2021 | 55 | 0.72 | 0.63 | ||
Biomass samples 2021 | 65 | 0.65 | 0.59 |
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Stettmer, M.; Maidl, F.-X.; Schwarzensteiner, J.; Hülsbergen, K.-J.; Bernhardt, H. Analysis of Nitrogen Uptake in Winter Wheat Using Sensor and Satellite Data for Site-Specific Fertilization. Agronomy 2022, 12, 1455. https://doi.org/10.3390/agronomy12061455
Stettmer M, Maidl F-X, Schwarzensteiner J, Hülsbergen K-J, Bernhardt H. Analysis of Nitrogen Uptake in Winter Wheat Using Sensor and Satellite Data for Site-Specific Fertilization. Agronomy. 2022; 12(6):1455. https://doi.org/10.3390/agronomy12061455
Chicago/Turabian StyleStettmer, Matthias, Franz-Xaver Maidl, Jürgen Schwarzensteiner, Kurt-Jürgen Hülsbergen, and Heinz Bernhardt. 2022. "Analysis of Nitrogen Uptake in Winter Wheat Using Sensor and Satellite Data for Site-Specific Fertilization" Agronomy 12, no. 6: 1455. https://doi.org/10.3390/agronomy12061455
APA StyleStettmer, M., Maidl, F.-X., Schwarzensteiner, J., Hülsbergen, K.-J., & Bernhardt, H. (2022). Analysis of Nitrogen Uptake in Winter Wheat Using Sensor and Satellite Data for Site-Specific Fertilization. Agronomy, 12(6), 1455. https://doi.org/10.3390/agronomy12061455