华北平原40年夏玉米作物系数变化及影响因素

刘梓萌; 李璐; 李昊天; 刘娜; 王鸿玺; 邵立威

doi:10.12357/cjea.20230197

华北平原40年夏玉米作物系数变化及影响因素

doi: 10.12357/cjea.20230197

刘梓萌^{1, 2,},
李璐^{1, 2},
李昊天^{1, 2},
刘娜^{1, 2},
王鸿玺³,
邵立威^1, ,

1.
中国科学院遗传与发育生物学研究所农业资源研究中心/中国科学院农业水资源重点实验室/河北省节水农业重点实验室　石家庄　050022
2.
中国科学院大学　北京　100049
3.
国网河北省电力有限公司营销服务中心　石家庄　050035

基金项目: 河北省创新团体项目(D2021503001)、河北省重点研发计划项目(21326410D)和国网河北省电力有限公司项目 (SGHEYX00SCJS2100077)资助

详细信息

作者简介:
刘梓萌, 主要从事农田节水机理与技术研究。E-mail: Liuzimeng21@mails.ucas.ac.cn

通讯作者:
邵立威, 主要从事作物水分高效利用研究。E-mail: liweishao@sjziam.ac.cn

中图分类号: S512.11
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出版历程
- 收稿日期: 2023-04-14
- 录用日期: 2023-06-01
- 网络出版日期: 2023-07-14
- 刊出日期: 2023-09-19

Changes and influencing factors of crop coefficient of summer maize during the past 40 years in the North China Plain

LIU Zimeng^{1, 2
,},
LI Lu^{1, 2},
LI Haotian^{1, 2},
LIU Na^{1, 2},
WANG Hongxi³,
SHAO Liwei^{1
, ,}

1.
Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences / Key Laboratory of Agricultural Water Resources, Chinese Academy of Sciences / Hebei Key Laboratory of Agricultural Water-saving, Shijiazhuang 050022, China
2.
University of Chinese Academy of Sciences, Beijing 100049, China
3.
State Grid Hebei Electric Power Co., Ltd. Marketing Service Center, Shijiazhuang 050035, China

Funds: The study was supported by the Hebei Innovation Group Project (D2021503001), the Hebei Key R&D Initiative Project (21326410D) and the Project of State Grid Hebei Electric Power Co., Ltd. (SGHEYX00SCJS2100077).

More Information

Corresponding author: E-mail: liweishao@sjziam.ac.cn

摘要

摘要: 作物系数(作物实际蒸散量与参考作物蒸散量之比, K_c)作为农田需耗水确定的关键参数, 对农业精准灌溉和节水具有重要的参考价值。研究作物系数如何受生产条件和气象条件变化的影响, 可为准确确定作物系数提供依据。本研究基于中国科学院栾城农业生态系统试验站1980—2018年充分灌溉条件下夏玉米作物系数变化规律及影响因素, 利用2019—2021年夏玉米不同灌水处理下的试验数据, 确定不同供水条件下夏玉米作物系数的计算方法。结果表明, 1980—2018年参考作物蒸散量(ET_o)基本保持稳定, 但存在年际波动。充分供水条件下夏玉米实际蒸散量(ET_c)在2005年之前保持年际间稳定, 近年来年际间波动幅度较大。作物实际蒸散量与参考作物蒸散量之比的作物系数多年平均值为0.91, 年际变异系数为12.36%。作物系数受作物产量和大气条件影响, 产量的增加伴随着夏玉米实际蒸散量的增加, 参考作物蒸散量主要受平均风速和日照时数的影响。分析表明作物系数由参考作物蒸散量和实际蒸散量共同决定, 且受夏玉米实际蒸散量的影响较大。灌水量的差异是造成相同年份不同处理间差异的主要因素。利用缺水处理下土壤水分状况和不同土层相对根长密度计算土壤水分胁迫系数, 结果表明使用缺水灌溉处理的土壤有效水分含量对夏玉米作物系数进行校正, 所得值与实际值最为接近, 可根据计划控制的土壤水分状况调整作物系数, 确定不同控水条件下的农田实际耗水量。
- 夏玉米 /
- 作物系数 /
- 充分灌溉 /
- 缺水灌溉 /
- 水分胁迫系数
Abstract: As a key parameter for determining crop water consumption, accurate estimation of the crop coefficient (K_c) is important for irrigation scheduling. K_c is influenced by changes in production and meteorological conditions. This study analyzed K_c changes from 1980 to 2018 for summer maize under sufficient water supply based on long-term field experiments at the Luancheng Agro-Ecosystem Experimental Station of the Chinese Academy of Sciences. Using data of the three most recent seasons from 2019 to 2021 for maize under normal and water-deficit conditions, the calibration coefficient of K_c by soil water content was developed and tested. The results showed that the reference crop evapotranspiration (ET_o) was stable from 1980 to 2018; however, seasonal fluctuations were observed. The actual evapotranspiration (ET_c) of summer maize under adequate water supply conditions has substantially changed over recent years. The multiyear average K_c for maize was 0.91, and the interseasonal variation coefficient was 12.36%. K_c is affected by crop yield and atmospheric conditions. An increase in yield was accompanied by an increase in the ET_c of summer maize. ET_o was mainly affected by average wind speed and sunshine hours. Our analysis revealed that K_c is determined by ET_o and ET_c and is greatly affected by the ET_c of summer maize. For the three most recent seasons, the difference in irrigation quantity was the main factor causing differences in K_c among the different treatments in the same season. K_c adjustment using different methods considering the soil water content could be used to estimate ET_c. Incorporating the root length distribution factor into the soil water status for K_c adjustment provided a better estimate of ET_c using the crop coefficient method. Therefore, K_c can be adjusted according to the root-zone soil moisture status to determine the actual crop water consumption.
- Summer maize /
- Crop coefficient /
- Full irrigation /
- Deficit irrigation /
- Water stress coefficient

HTML全文

图 1 1980—2018年夏玉米生长季气象因素年际变化

Tmax: 最高空气温度; Tmin: 最低空气温度; RH: 相对湿度; Wind: 2 m处平均风速; SH: 日照时数。Tmax represents the maximum air temperature, Tmin represents the minimum air temperature, RH represents the relative humidity, Wind represents the average wind speed at 2 m, and SH represents the sunshine hours.

Figure 1. Variation of meteorological factors during the growth seasons of summer maize from 1980 to 2018

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图 2 1980—2018年夏玉米生长季参考作物蒸散量(ET_o)年际变化

Figure 2. Variation of reference crop evapotranspiration (ET_o) during the growth seasons of summer maize from 1980 to 2018

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图 3 1980—2018年夏玉米产量与实际蒸散量年际变化及相关关系

Figure 3. Variation and correlation analysis of summer maize yield and actual evapotranspiration from 1980 to 2018

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图 4 1980—2018年夏玉米作物系数年际变化

Figure 4. Variation of crop coefficient of summer maize from 1980 to 2018

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图 5 1980—2018年夏玉米作物系数与参考作物蒸散量和实际蒸散量的相关关系

Figure 5. Correlation analysis of crop coefficient, reference crop evapotranspiration and actual evapotranspiration during the growth seasons of summer maize from 1980 to 2018

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图 6 2019—2021年充分灌水条件下夏玉米生育期作物系数变化

Figure 6. Variation of crop coefficient of summer maize under full irrigation during different growth stages from 2019 to 2021

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图 7 基于不同订正方法的夏玉米水分胁迫系数在各生育时期的动态变化

K_s1、K_s2、K_s3和K_s4为4种不同计算方法所得水分胁迫系数。K_s1, K_s2, K_s3 and K_s4 represent the water stress coefficients calculated by four methods.

Figure 7. Dynamic changes of water stress coefficients of summer maize at different growth stages calculated by different correction methods

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图 8 2019—2021年根据不同水分胁迫系数计算所得夏玉米不同生育期实际蒸散量

ET_c为实测实际蒸散量; ET_c1、ET_c2、ET_c3和ET_c4分别表示根据水分胁迫系数K_s1、K_s2、K_s3和K_s4计算所得实际蒸散量, K_s1、K_s2、K_s3和K_s4为4种不同计算方法所得水分胁迫系数。Ini为生育初期, Dev为快速发育期, Mid为生育中期, End为生育末期, Total为全生育期。ET_c represents the measured actual evapotranspiration. ET_c1, ET_c2, ET_c3 and ET_c4 represent the actual evapotranspiration calculated by K_s1, K_s2, K_s3 and K_s4, respectively. K_s1, K_s2, K_s3 and K_s4 represent the water stress coefficients calculated by four methods. Ini represents initial stage, Dev represents developing stage, Mid represents middle stage, End represents end stage, and Total represents whole growth stage.

Figure 8. Actual evapotranspiration during different growth stages of summer maize calculated from 2019 to 2021 according to different water stress coefficients

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表 1 1980—2021年长期定位灌溉试验期间夏玉米品种及施肥量变化

Table 1. Changes of cultivar and fertilization rate of summer maize in the long-term irrigation experiment from 1980 to 2021

时期 Period	栽培品种 Cultivar	两季作物总施肥量 Total fertilizer use amount of two season crops	施肥管理 Management of fertilizer application
20世纪80年代 1980s	单杂交品种 Single hybrid	150~200 kg(N)∙hm⁻², 80~100 kg(P₂O₅)∙hm⁻², 20 kg(K₂O)∙hm⁻²	全部磷肥和钾肥以及1/4氮肥作为基肥, 在冬小麦播前全部施入。剩余氮肥分为两等份, 分别在冬小麦拔节期和玉米大喇叭口期随灌溉水或降水施入 All phosphate fertilizer, all potassium fertilizer, and 1/4 of nitrogen fertilizer are used as the base fertilizer, and all are applied to the field before winter wheat sowing. The remaining nitrogen fertilizer is divided into two equal parts, which are applied with irrigation water or precipitation during the jointing stage of winter wheat and the big bell mouth stage of maize
20世纪90年代 1990s	紧凑型杂交种 Compact hybrid	250~300 kg(N)∙hm⁻², 100~150 kg(P₂O₅)∙hm⁻², 20 kg(K₂O)∙hm⁻²
20世纪90年代末至21世纪初 From end of 1990s to early 21st century	大穗型杂交种 Large panicle hybrid	350~375 kg(N)∙hm⁻², 130~170 kg(P₂O₅)∙hm⁻², 20 kg(K₂O)∙hm⁻²
21世纪初至21世纪 20年代初 From early 21st century to early 2020s	杂交种“郑单958” Hybrid of “Zhengdan 958”	400~425 kg(N)∙hm⁻², 180~200 kg(P₂O₅)∙hm⁻², 30~40 kg(K₂O)∙hm⁻²

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表 2 不同水分胁迫系数多年平均值所得实际蒸散量及精度比较

Table 2. Comparison of the actual evapotranspiration calculated from the annual average of different water stress coefficients and precision comparison between different water stress coefficients

生育期 Growth stage	2019—2021年平均实际蒸散量 Average actual evapotranspiration from 2019 to 2021					计算精度 Calculation accuracy
生育期 Growth stage	ET_c (mm)	ET_c1 (mm)	ET_c2 (mm)	ET_c3 (mm)	ET_c4 (mm)	ET_c1−ET_c (%)	ET_c2−ET_c (%)	ET_c3−ET_c (%)	ET_c4−ET_c (%)
生育初期 Initial stage	11.98	16.08	14.88	15.65	14.17	34.25	24.17	30.67	18.31
快速发育期 Developing stage	54.69	71.90	62.93	71.92	62.96	31.46	15.06	31.51	15.13
生育中期 Mid-growth stage	100.22	99.92	89.14	100.62	90.28	0.30	11.06	0.40	9.92
生育后期 Late-growth stage	71.15	55.88	41.31	54.88	39.67	5.93	30.46	7.62	33.23
全生育期 Whole growth stage	234.97	248.18	230.97	257.42	216.90	5.62	1.70	9.55	7.96
平均值 Average						15.51	16.49	15.95	16.91
ET_c为实测实际蒸散量; ET_c1、ET_c2、ET_c3和ET_c4分别表示根据水分胁迫系数 K_s1、K_s2、K_s3和K_s4计算所得实际蒸散量平均值, K_s1、K_s2、K_s3和K_s4为4种不同计算方法所得水分胁迫系数。ET_c1−ET_c、ET_c2−ET_c、ET_c3−ET_c、ET_c4−ET_c分别表示ET_c1、ET_c2、ET_c3、ET_c4与ET_c的差异程度。ET_c represents the measured actual evapotranspiration. ET_c1, ET_c2, ET_c3 and ET_c4 represent the actual evapotranspiration calculated by K_s1, K_s2, K_s3 and K_s4, respectively. K_s1, K_s2, K_s3 and K_s4 represent the water stress coefficients calculated by four methods. ET_c1−ET_c, ET_c2−ET_c, ET_c3−ET_c and ET_c4−ET_c indicate the differences of ET_c1, ET_c2, ET_c3, ET_c4 compared with ET_c, respectively.

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