Factors Affecting Nitrogen Use Efficiency and Grain Yield of Summer Maize on Smallholder Farms in the North China Plain
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Site
2.2. Data Collection
2.3. Data Analysis
- (a)
- Grouping the data points (Y = yield, X = management factors).
- (b)
- Arrange X (X1, X2, …, Xn) in ascending order and Y (Y1, Y2, …, Yn) in descending order.
- (c)
- The first boundary data is Y1, the second boundary data is identified by the IF formula (Y2 > Y1, Y2, Y1).
- (d)
- When the boundary data equals Yatt, the rest of the X and Y values are arranged in descending order.
- (e)
- The final boundary data is Yn; the previous boundary data is identified by the IF formula (Yn−1 > Yn, Yn−1, Yn), and is continued to Yatt.
3. Results
3.1. Variation of the Summer Maize Yield and PFPN
3.2. Relationship between Summer Maize Yield and PFPN
3.3. Key Limiting Management Factors of Yield and PFPN
4. Discussion
4.1. Effects of Plant Density and N Application on Yield and PFPN
4.2. Other Limiting Management Factors
4.3. Variation of Yield and PFPN On Farms
4.4. Yield and PFPN On Farms
5. Conclusions
Supplementary Materials
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Region | Per Capita Arable Land Area | Annual Rainfall | Soil Nutrient Content * | ||||
---|---|---|---|---|---|---|---|
Total N | SOM ** | Olsen-P | Available Potassium | pH | |||
ha | mm | g kg−1 | g kg−1 | mg kg−1 | mg kg−1 | ||
Laoling | 0.12 | 527 | 1.15 | 16.6 | 21.0 | 147.9 | 7.31 |
Xushui | 0.09 | 547 | 0.86 | 10.6 | 19.4 | 114.1 | 7.70 |
Quzhou | 0.08 | 556 | 1.04 | 13.6 | 20.4 | 103.2 | 8.21 |
Variations | Yield | PFPN | |||
---|---|---|---|---|---|
SD * (t ha−1) | CV ** (%) | SD (kg ha−1) | CV (%) | ||
NCP | 1.04 | 10.0 | 9.0 | 18.0 | |
Laoling | 0.24 | 2.6 | 9.1 | 22.9 | |
Xushui | 0.18 | 1.7 | 2.1 | 3.9 | |
Quzhou | 1.03 | 8.9 | 8.3 | 14.6 | |
Laoling | 2015 | 1.21 | 13.2 | 8.2 | 24.6 |
2016 | 1.37 | 14.4 | 17.9 | 38.7 | |
Xushui | 2015 | 1.23 | 11.6 | 13.6 | 24.0 |
2016 | 1.14 | 11.0 | 10.0 | 18.7 | |
Quzhou | 2015 | 1.15 | 10.6 | 17.3 | 34.2 |
2016 | 1.06 | 8.6 | 18.2 | 29.2 |
Laoling | Xushui | Quzhou | ||||
---|---|---|---|---|---|---|
Categories | HH | LL | HH | LL | HH | LL |
Numbers | 5 | 134 | 15 | 43 | 53 | 46 |
Percentage (%) | 3.1 | 83.7 | 16 | 45.7 | 29.1 | 25.3 |
Density (plants ha−1) | 67,019.4a * | 59,709.7bc | 63,550.8ab | 56,272.3c | 58,319.1bc | 55,681.0c |
N amount (kg ha−1) | 164.6c | 274.7a | 163.1c | 215.2b | 159.5c | 262.7a |
P2O5 amount (kg ha−1) | 45.5a | 54.5a | 56.1a | 68.8a | 53.3a | 58.0a |
K2O amount (kg ha−1) | 45.5c | 43.9c | 71.0ab | 75.4a | 51.7c | 57.4bc |
Sowing date (June) | 13.8a | 13.8a | 15.7a | 15.8a | 14.3a | 15.8a |
Irrigation times | 1.0ab | 1.5a | 0.9ab | 0.7b | 0.5b | 1.0ab |
Yield (t ha−1) | 11.9a | 8.99c | 11.6a | 9.59bc | 12.2a | 10.0b |
PFPN (kg kg−1) | 73.5a | 34.3c | 71.8a | 45.6b | 77.2a | 40.2bc |
Factors | Level | Degree of Freedom | Yield (t h−1) | PFPN (kg kg−1) | ||||||
---|---|---|---|---|---|---|---|---|---|---|
Parameter Estimate | 95% Confidence | p-Values | Parameter Estimate | 95% Confidence | p-Values | |||||
Lower | Upper | Lower | Upper | |||||||
Intercept | 13.92 | 12.34 | 15.51 | 62.57 | 48.48 | 76.65 | ||||
Year | 2015 | 243 | −1.23 | −1.60 | −0.86 | - | −9.17 | −12.43 | −5.91 | - |
2016 | 191 | 0.00 | - | - | - | 0.00 | - | - | - | |
Site | Laoling | 159 | −2.71 | −3.22 | −2.21 | <0.0001 | −18.79 | −23.29 | −14.30 | <0.0001 |
Xushui | 93 | −1.38 | −1.76 | −0.99 | <0.0001 | -0.93 | −4.34 | 2.49 | 0.5952 | |
Quzhou | 181 | 0.00 | - | - | - | 0.00 | - | - | - | |
Density | Low * | 58 | −1.38 | −2.02 | −0.73 | <0.0001 | 0.08 | −5.64 | 5.80 | 0.9785 |
Medium | 279 | −0.91 | −1.37 | −0.45 | <0.0001 | −0.89 | −4.97 | 3.19 | 0.6682 | |
High | 96 | 0.00 | - | - | - | 0.00 | - | - | - | |
N amount | Low | 46 | 0.04 | −0.63 | 0.70 | 0.9168 | 48.68 | 42.75 | 54.62 | <0.0001 |
Medium | 232 | −0.20 | −0.70 | 0.30 | 0.4366 | 23.09 | 18.62 | 27.56 | <0.0001 | |
High | 155 | 0.00 | - | - | - | 0.00 | 0.00 | 0.00 | - | |
P2O5 amount | Low | 161 | 0.47 | −0.13 | 1.06 | 0.1243 | −2.29 | −7.56 | 2.98 | 0.3943 |
Medium | 259 | 0.45 | −0.16 | 1.05 | 0.1465 | −5.88 | −11.23 | −0.54 | 0.0315 | |
High | 13 | 0.00 | - | - | - | 0.00 | - | - | - | |
K2O amount | Low | 83 | 0.24 | −0.80 | 1.29 | 0.6488 | 1.67 | −7.63 | 10.97 | 0.7249 |
Medium | 347 | 0.34 | −0.68 | 1.36 | 0.5106 | 3.40 | −5.66 | 12.46 | 0.4629 | |
High | 3 | 0.00 | - | - | - | 0.00 | - | - | - | |
Sowing date | Low | 7 | 1.17 | 0.30 | 2.05 | 0.0089 | 7.49 | −0.27 | 15.26 | 0.0593 |
Medium | 373 | 0.42 | 0.06 | 0.77 | 0.0216 | −2.21 | −5.35 | 0.94 | 0.1693 | |
High | 53 | 0.00 | - | - | - | 0.00 | - | - | - | |
Irrigation times | Low | 115 | −0.85 | −1.38 | −0.31 | 0.0021 | −5.97 | −10.73 | −1.21 | 0.0144 |
Medium | 224 | −0.67 | −1.03 | −0.30 | 0.0004 | −3.19 | −6.44 | 0.05 | 0.0543 | |
High | 94 | 0.00 | - | - | - | 0.00 | - | - | - | |
Insecticide times | Low | 34 | 0.13 | −0.40 | 0.67 | 0.6249 | −1.72 | −6.51 | 3.07 | 0.4826 |
Medium | 297 | 0.09 | −0.28 | 0.45 | 0.6414 | −2.25 | −5.49 | 0.99 | 0.1744 | |
High | 102 | 0.00 | - | - | - | 0.00 | - | - | - | |
Herbicide times | Low | 321 | −0.76 | −1.22 | −0.30 | 0.0013 | −2.30 | −6.41 | 1.80 | 0.2724 |
Medium | 113 | 0.00 | - | - | - | 0.00 | - | - | - | |
Bactericide times | Low | 123 | −0.98 | −1.61 | −0.35 | 0.0023 | −0.79 | −6.35 | 4.77 | 0.7808 |
Medium | 280 | −0.98 | −1.55 | −0.41 | 0.0008 | −7.22 | −12.27 | −2.18 | 0.0052 | |
High | 30 | 0.00 | - | - | - | 0.00 | - | - | - | |
Density *N | Low–Low | 6 | −0.45 | −1.64 | 0.74 | 0.4567 | −2.04 | −12.60 | 8.52 | 0.7052 |
Low–Medium | 30 | 0.02 | −0.79 | 0.82 | 0.9669 | −11.15 | −18.29 | −4.00 | 0.0024 | |
Low–High | 20 | 0.00 | - | - | - | 0.00 | - | - | - | |
Medium–Low | 26 | 0.50 | −0.31 | 1.31 | 0.2268 | −5.07 | −12.25 | 2.11 | 0.1671 | |
Medium–Medium | 149 | 0.54 | −0.03 | 1.11 | 0.064 | −6.28 | −11.35 | −1.22 | 0.0155 | |
Medium–High | 102 | 0.00 | - | - | - | 0.00 | - | - | - | |
High–Low | 14 | 0.00 | - | - | - | 0.00 | - | - | - | |
High–Medium | 50 | 0.00 | - | - | - | 0.00 | - | - | - | |
High–High | 30 | 0.00 | - | - | - | 0.00 | - | - | - |
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Chen, G.; Cao, H.; Liang, J.; Ma, W.; Guo, L.; Zhang, S.; Jiang, R.; Zhang, H.; Goulding, K.W.T.; Zhang, F. Factors Affecting Nitrogen Use Efficiency and Grain Yield of Summer Maize on Smallholder Farms in the North China Plain. Sustainability 2018, 10, 363. https://doi.org/10.3390/su10020363
Chen G, Cao H, Liang J, Ma W, Guo L, Zhang S, Jiang R, Zhang H, Goulding KWT, Zhang F. Factors Affecting Nitrogen Use Efficiency and Grain Yield of Summer Maize on Smallholder Farms in the North China Plain. Sustainability. 2018; 10(2):363. https://doi.org/10.3390/su10020363
Chicago/Turabian StyleChen, Guangfeng, Hongzhu Cao, Jun Liang, Wenqi Ma, Lufang Guo, Shuhua Zhang, Rongfeng Jiang, Hongyan Zhang, Keith W. T. Goulding, and Fusuo Zhang. 2018. "Factors Affecting Nitrogen Use Efficiency and Grain Yield of Summer Maize on Smallholder Farms in the North China Plain" Sustainability 10, no. 2: 363. https://doi.org/10.3390/su10020363