Insights into the Spatial and Temporal Variability of Soil Attributes in Irrigated Farm Fields and Correlations with Management Practices: A Multivariate Statistical Approach
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Area
2.2. Sampling and Data Collection
2.3. Statistical Analysis
3. Results and Discussion
3.1. Soil Physical–Chemical Properties
3.2. Correlation and Data Structure
3.2.1. Layer 0–20 cm
3.2.2. Layer 20–40 cm
3.3. Discriminant Factors and Variables
3.3.1. Layer 0–20 cm
3.3.2. Layer 20–40 cm
4. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Year | Field | Crop | Sowing (dd/mm) | Seasonal Irrigation Water (m3 ha−1) | First Irrigation (dd/mm) | Last Irrigation (dd/mm) | Fertilizer N (kg N ha−1) | Fertilizer P (kg P2O5 ha−1) | Fertilizer K (kg K2O ha−1) | Other Fertilizers (kg ha−1) | Pesticides (Active Substance) | Harvest (dd/mm) | Yield (kg ha−1) |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2018 | P3 | Sunflower | 18/04 | 2517 | 19/04 | 01/08 | 127 | 34 | - | 16 SO3; 0.2 B | pre-emergence herbicide (pendimethalin); insecticide (deltamethrin) | 27/08 | 3470 |
P4 | Sunflower | 27/04 | 4606 | 28/04 | 26/08 | 109 | 40 | 12 | 16 SO3 | pre-emergence herbicide (pendimethalin) | 18/09 | 4156 | |
P5 | Maize | 18/07 | 4800 | 18/07 | 04/10 | 202 | 144 | 216 | 27 SO3 | post-emergence herbicide (foramsulfuron + isoxadifen-ethyl) | 17/01 1 | 5500 | |
2019 | P3 | Maize | 13/06 | 7500 | 2 | 2 | 253 | - | - | - | post-emergence herbicide (mesotrione + S-metolachlor + terbuthylazine); insecticide (lambda-cyhalothrin) | 17/11 | 11000 |
P4 | Clover | 03/01 | 1510 | 18/04 | 24/06 | - | 88 | - | 0.2 SO3; 0.2 B; 0.1 MgO | - | 18/09 | 1703 | |
P5 | Sunflower | 16/05 | 3570 | 20/05 | 30/08 | 81 | 19 | 20 | 7 SO3 | pre-emergence herbicides (pendimethalin, glyphosate) | 15/09 | 3257 | |
2020 | P3 | Sunflower | 09/03 | 5420 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 13/08 | 8660 |
P4 | Onion | 11/01 | 3210 | 11/01 | 24/08 | 113 | 1 | 0.1 | 210 SO3; 65 CaO; 2 Zn; 1 Mn; 0.1 MgO | pre- and post-emergence herbicides (aclonifen, clethodime) | 21/08 | 26,848 | |
P5 | Maize | 15/06 | 5160 | 15/06 | 15/09 | 82 | 59 | 121 | 5 SO3; 3 Zn | pre- and post-emergence herbicides (glyphosate, MCPA, 2,4-D + florasulam, mesotrione + S-metolachlor + terbuthylazine); insecticides (lambda-cyhalothrin, chlorantraniliprole) | 15/10 | 9182 |
Site | C. Sand (g kg−1) | F. Sand (g kg−1) | Silt (g kg−1) | Clay (g kg−1) | CEC (cmol (+) kg−1) |
---|---|---|---|---|---|
P3 | 197.6 (±10.0) | 230.7 (±6.0) | 192.1 (±15.5) | 379.6 (±1.8) | 56.5 (±0.3) |
P4 | 160.5 (±11.1) | 159.2 (±6.5) | 248.3 (±1.4) | 432.0 (±16.1) | 57.0 (±0.8) |
P5 | 163.7 (±9.8) | 177.5 (±14.2) | 287.6 (±19.1) | 371.2 (±25.9) | 53.6 (±2.1) |
Site | C. Sand (g kg−1) | F. Sand (g kg−1) | Silt (g kg−1) | Clay (g kg−1) | CEC (cmol (+) kg−1) |
---|---|---|---|---|---|
P3 | 192.2 (±11.00) | 232.4 (±5.6) | 192.7 (±15.7) | 375.7 (±2.3) | 58.1 (±0.6) |
P4 | 164.1 (±19.08) | 167.2 (±6.4) | 246.7 (±9.5) | 422.0 (±17.0) | 57.9 (±1.2) |
P5 | 176.0 (±9.82) | 173.3 (±12.6) | 243.8 (±5.8) | 406.9 (±17.4) | 53.9 (±1.4) |
Date | Site | pH | EC (dS m−1) | SOM (g kg−1) | N (%) | P (mg P2O5 kg−1) | K (mg K2O kg−1) |
---|---|---|---|---|---|---|---|
T1 | P3 | 8.39 (±0.03) | 0.16 (±0.00) | 15.8 (±0.5) | 0.08 (±0.00) | 248.61 (±31.32) | 115.07 (±9.21) |
P4 | 8.28 (±0.06) | 0.13 (±0.00) | 12.8 (±0.4) | 0.06 (±0.00) | 221.34 (±19.07) | 206.59 (±14.06) | |
P5 | 8.02 (±0.03) | 0.18 (±0.01) | 11.4 (±0.6) | 0.08 (±0.00) | 418.63 (±88.63) | 236.78 (±14.02) | |
T2 | P3 | 8.34 (±0.03) | 0.35 (±0.01) | 12.2 (±0.6) | 0.09 (±0.00) | 124.46 (±17.60) | 106.57 (±7.30) |
P4 | 7.89 (±0.03) | 0.35 (±0.02) | 19.6 (±2.4) | 0.07 (±0.00) | 143.64 (±10.22) | 149.26 (±4.68) | |
P5 | 8.45 (±0.02) | 0.24 (±0.01) | 19.1 (±1.8) | 0.08 (±0.01) | 326.53 (±32.45) | 367.04 (±16.31) | |
T3 | P3 | 8.40 (±0.01) | 0.28 (±0.02) | 10.6 (±0.8) | 0.09 (±0.00) | 145.24 (±12.73) | 102.62 (±13.52) |
P4 | 1 | ||||||
P5 | 1 | ||||||
T4 | P3 | 8.08 (±0.02) | 0.29 (±0.01) | 10.0 (±0.4) | 0.10 (±0.00) | 148.57 (±14.68) | 94.98 (±6.93) |
P4 | 8.25 (±0.02) | 0.26 (±0.01) | 6.9 (±0.4) | 0.08 (±0.00) | 115.81 (±6.99) | 145.16 (±5.96) | |
P5 | 8.06 (±0.04) | 0.30 (±0.01) | 16.0 (±0.6) | 0.10 (±0.00) | 239.86 (±21.76) | 226.06 (±14.34) | |
T5 | P3 | 7.92 (±0.01) | 0.58 (±0.01) | 15.0 (±0.2) | 0.10 (±0.00) | 180.82 (±18.98) | 147.75 (±18.55) |
P4 | 7.80 (±0.01) | 0.46 (±0.02) | 10.4 (±0.2) | 0.09 (±0.01) | 106.32 (±6.64) | 261.43 (±48.24) | |
P5 | 1 |
Date | Site | pH | EC (dS m−1) | SOM (g kg−1) | N (%) | P (mg P2O5 kg−1) | K (mg K2O kg−1) |
---|---|---|---|---|---|---|---|
T1 | P3 | 8.49 (±0.02) | 0.15 (±0.00) | 16.9 (±1.4) | 0.07 (±0.00) | 144.85 (±7.02) | 94.82 (±7.05) |
P4 | 8.19 (±0.05) | 0.16 (±0.00) | 8.2 (±0.2) | 0.05 (±0.00) | 131.13 (±4.44) | 139.03 (±3.62) | |
P5 | 8.09 (±0.07) | 0.14 (±0.01) | 7.9 (±0.6) | 0.06 (±0.00) | 258.99 (±67.76) | 150.23 (±11.43) | |
T2 | P3 | 8.40 (±0.03) | 0.30 (±0.02) | 11.2 (±0.4) | 0.08 (±0.00) | 106.20 (±15.77) | 96.99 (±6.14) |
P4 | 7.97 (±0.02) | 0.29 (±0.02) | 18.5 (±3.1) | 0.07 (±0.00) | 83.74 (±1.71) | 139.38 (±3.09) | |
P5 | 8.49 (±0.02) | 0.30 (±0.02) | 16.8 (±1.5) | 0.07 (±0.00) | 197.73 (±18.97) | 183.27 (±9.77) | |
T3 | P3 | 8.35 (±0.02) | 0.29 (±0.01) | 10.2 (±0.9) | 0.08 (±0.01) | 148.44 (±12.28) | 121.46 (±19.84) |
P4 | 1 | ||||||
P5 | 1 | ||||||
T4 | P3 | 8.10 (±0.01) | 0.32 (±0.01) | 9.8 (±0.8) | 0.10 (±0.00) | 118.42 (±11.96) | 86.27 (±7.98) |
P4 | 1 | ||||||
P5 | 7.98 (±0.01) | 0.37 (±0.01) | 15.1 (±0.8) | 0.09 (±0.00) | 192.95 (±16.97) | 195.35 (±16.83) | |
T5 | P3 | 8.11 (±0.01) | 0.28 (±0.00) | 13.3 (±0.4) | 0.09 (±0.00) | 133.02 (±14.65) | 73.48 (±9.30) |
P4 | 7.83 (±0.05) | 0.41 (±0.04) | 9.0 (±0.4) | 0.09 (±0.01) | 74.64 (±4.27) | 164.78 (±11.08) | |
P5 | 1 |
pH | EC | SOM | N | P | K | C. Sand | F. Sand | Silt | Clay | CEC | |
---|---|---|---|---|---|---|---|---|---|---|---|
pH | 1.000 | ||||||||||
EC | −0.487 | 1.000 | |||||||||
SOM | 0.093 | 0.011 | 1.000 | ||||||||
N | −0.270 | 0.591 | 0.150 | 1.000 | |||||||
P | 0.273 | −0.461 | 0.426 | 0.021 | 1.000 | ||||||
K | −0.108 | −0.124 | 0.348 | 0.020 | 0.538 | 1.000 | |||||
C. Sand | 0.068 | 0.050 | −0.075 | 0.047 | −0.162 | −0.449 | 1.000 | ||||
F. Sand | 0.103 | 0.108 | −0.025 | 0.178 | −0.119 | −0.441 | 0.920 | 1.000 | |||
Silt | −0.078 | −0.117 | 0.198 | −0.030 | 0.119 | 0.447 | −0.556 | −0.396 | 1.000 | ||
Clay | −0.123 | 0.086 | −0.180 | −0.086 | 0.088 | 0.155 | −0.554 | −0.564 | −0.197 | 1.000 | |
CEC | −0.170 | 0.164 | −0.245 | 0.043 | −0.196 | −0.151 | −0.033 | −0.097 | −0.302 | 0.434 | 1.000 |
Factor 1 | Factor 2 | Factor 3 | Factor 4 | |
---|---|---|---|---|
pH | 0.215 | 0.043 | −0.719 | −0.186 |
EC | 0.093 | 0.111 | 0.893 | 0.070 |
SOM | −0.061 | −0.195 | 0.100 | −0.542 |
N | 0.198 | 0.035 | 0.753 | −0.251 |
P | 0.015 | 0.068 | −0.257 | −0.799 |
K | −0.323 | −0.092 | 0.073 | −0.741 |
C. Sand | 0.897 | −0.259 | 0.004 | 0.152 |
F. Sand | 0.943 | −0.256 | 0.053 | 0.100 |
Silt | −0.793 | −0.527 | −0.042 | −0.169 |
Clay | −0.413 | 0.861 | 0.001 | 0.008 |
CEC | 0.008 | 0.830 | 0.088 | 0.183 |
Eigenvalues | 2.988 | 2.224 | 1.837 | 1.206 |
% Total variance | 27.16 | 20.22 | 16.70 | 10.97 |
%. Accumulated variance | 27.16 | 47.38 | 64.08 | 75.04 |
pH | EC | SOM | N | P | K | C. Sand | F. Sand | Silt | Clay | CEC | |
---|---|---|---|---|---|---|---|---|---|---|---|
pH | 1.000 | ||||||||||
EC | −0.301 | 1.000 | |||||||||
SOM | 0.234 | 0.124 | 1.000 | ||||||||
N | −0.172 | 0.672 | 0.326 | 1.000 | |||||||
P | 0.397 | −0.111 | 0.224 | −0.042 | 1.000 | ||||||
K | −0.232 | 0.209 | 0.183 | −0.036 | 0.302 | 1.000 | |||||
C. Sand | 0.019 | 0.092 | 0.135 | 0.054 | 0.082 | −0.073 | 1.000 | ||||
F. Sand | 0.266 | 0.001 | 0.062 | 0.176 | −0.013 | −0.541 | 0.712 | 1.000 | |||
Silt | −0.181 | −0.064 | −0.065 | −0.118 | −0.105 | 0.405 | −0.868 | −0.820 | 1.000 | ||
Clay | −0.130 | −0.022 | −0.120 | −0.157 | 0.103 | 0.286 | −0.800 | −0.894 | 0.691 | 1.000 | |
CEC | −0.026 | −0.147 | −0.178 | −0.023 | −0.134 | −0.190 | −0.517 | −0.121 | 0.278 | 0.289 | 1.000 |
Factor 1 | Factor 2 | Factor 3 | Factor 4 | |
---|---|---|---|---|
pH | 0.195 | −0.288 | 0.241 | 0.752 |
EC | 0.038 | 0.863 | −0.148 | −0.200 |
SOM | 0.063 | 0.363 | −0.092 | 0.562 |
N | 0.032 | 0.894 | 0.124 | 0.066 |
P | −0.141 | −0.211 | −0.443 | 0.594 |
K | −0.464 | 0.233 | −0.695 | 0.228 |
C. Sand | 0.929 | 0.024 | −0.275 | 0.005 |
F. Sand | 0.925 | 0.041 | 0.237 | 0.085 |
Silt | −0.869 | −0.007 | −0.099 | −0.050 |
Clay | −0.869 | −0.052 | 0.127 | −0.034 |
CEC | −0.302 | 0.043 | 0.758 | 0.094 |
Eigenvalues | 3.614 | 1.953 | 1.611 | 1.152 |
% Total variance | 32.85 | 17.75 | 14.65 | 10.47 |
%. Accumulated variance | 32.85 | 50.60 | 65.25 | 75.72 |
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Tomaz, A.; Martins, I.; Catarino, A.; Mourinha, C.; Dôres, J.; Fabião, M.; Boteta, L.; Coutinho, J.; Patanita, M.; Palma, P. Insights into the Spatial and Temporal Variability of Soil Attributes in Irrigated Farm Fields and Correlations with Management Practices: A Multivariate Statistical Approach. Water 2022, 14, 3216. https://doi.org/10.3390/w14203216
Tomaz A, Martins I, Catarino A, Mourinha C, Dôres J, Fabião M, Boteta L, Coutinho J, Patanita M, Palma P. Insights into the Spatial and Temporal Variability of Soil Attributes in Irrigated Farm Fields and Correlations with Management Practices: A Multivariate Statistical Approach. Water. 2022; 14(20):3216. https://doi.org/10.3390/w14203216
Chicago/Turabian StyleTomaz, Alexandra, Inês Martins, Adriana Catarino, Clarisse Mourinha, José Dôres, Marta Fabião, Luís Boteta, João Coutinho, Manuel Patanita, and Patrícia Palma. 2022. "Insights into the Spatial and Temporal Variability of Soil Attributes in Irrigated Farm Fields and Correlations with Management Practices: A Multivariate Statistical Approach" Water 14, no. 20: 3216. https://doi.org/10.3390/w14203216
APA StyleTomaz, A., Martins, I., Catarino, A., Mourinha, C., Dôres, J., Fabião, M., Boteta, L., Coutinho, J., Patanita, M., & Palma, P. (2022). Insights into the Spatial and Temporal Variability of Soil Attributes in Irrigated Farm Fields and Correlations with Management Practices: A Multivariate Statistical Approach. Water, 14(20), 3216. https://doi.org/10.3390/w14203216