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Acta Agronomica Sinica ›› 2019, Vol. 45 ›› Issue (11): 1725-1734.doi: 10.3724/SP.J.1006.2019.91008

• TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY • Previous Articles     Next Articles

Regulation effects of water and nitrogen on wheat yield and biomass in different precipitation years

RU Xiao-Ya1,LI Guang2,*(),CHEN Guo-Peng2,ZHANG Tong-Shuai2,YAN Li-Juan3,*()   

  1. 1 College of Information Science and Technology, Gansu Agricultural University, Lanzhou 730070, Gansu, China
    2 College of Forestry, Gansu Agricultural University, Lanzhou 730070, Gansu, China
    3 College of Agronomy, Gansu Agricultural University, Lanzhou 730070, Gansu, China
  • Received:2019-01-23 Accepted:2019-06-24 Online:2019-11-12 Published:2019-07-15
  • Contact: Guang LI,Li-Juan YAN E-mail:lig@gsau.edu.cn;yanlj@gsau.edu.cn
  • Supported by:
    The work was supported by the National Natural Science Foundation of China(31560378);The work was supported by the National Natural Science Foundation of China(31560343);The work was supported by the National Natural Science Foundation of China(31660348);the Gansu Provincial Key Research and Development Program(18YF1NA070);the Gansu Provincial Higher Education Collaborative Innovation Team Project(2018C-16)

Abstract:

Water and nitrogen are the main factors affecting grain production in the rain-fed agriculture area of the Loess Plateau in Northwest China, but their yield-increasing effects will be affected by the type of precipitation. In this paper, the APSIM model was used to conduct water-nitrogen coupling test based on the meteorological data of the experimental area from 1971 to 2018. The effects of different precipitation years on the variation coefficient and sustainability index of wheat yield and biomass were analyzed. In addition, the relationship between annual yield and nitrogen application rate and precipitation was also discussed. According to the model the wheat yield and biomass determination coefficient R 2 was above 0.90, the D index was above 0.95, and the normalized root mean square error (NRMSE) was below 15%, indicating that the model has good model fitting and adaptability in the study area. Based on natural conventional rainfall in each year, we explored the optimized combination of water and nitrogen for the three types of annual yields using the binary quadratic regression equation. When the potential yield of wheat in drought year reached 3492.6 kg hm -2, the precipitation increased by 39.73% and the nitrogen consumption was 182.73 kg hm -2; when the potential yield of wheat in flat water year reached 4514.5 kg hm -2, the precipitation increased by 45.26%, the nitrogen consumption was 208.26 kg hm -2; and when the potential yield in wet year reached 4890.3 kg hm -2, the precipitation increased by 46.31%, the amount of nitrogen was 211.15 kg hm -2. Among them, precipitation increased on the basis of the total annual precipitation in that year. The research results can provide a theoretical basis for alleviating wheat drought and nutrient stresses in different precipitation years in the study area, saving fertilizer resources and keeping sustainable development of agriculture.

Key words: precipitation year pattern, APSIM model, biomass, yield

Table 1

Soil parameters"

土层
Soil layer (cm)
田间最大持水量
Drained upper limit (mm mm-1)
小麦有效
水分下限
Wheat low limit
(mm mm-1)
容重
Bulk density
(g cm-3)
萎蔫系数
Wilting coefficient (mm mm-1)
饱和含水量
Saturated moisture
( mm mm-1)
有机碳
Organic carbon (%)
铵态氮
NH4-N
(mg kg-1)
硝态氮
NO3-N
(mg kg-1)
>0-5 0.27 0.09 1.29 0.08 0.46 0.95 6.30 19.10
>5-10 0.27 0.09 1.23 0.08 0.49 0.95 5.20 15.20
>10-30 0.27 0.09 1.32 0.08 0.45 0.96 5.10 23.10
>30-50 0.27 0.09 1.20 0.08 0.50 0.85 4.90 16.60
>50-80 0.26 0.09 1.14 0.09 0.52 0.54 4.60 16.80
>80-110 0.27 0.10 1.14 0.09 0.52 0.26 4.80 18.20
>110-140 0.27 0.11 1.13 0.11 0.48 0.20 4.80 16.40
>140-170 0.27 0.13 1.12 0.13 0.53 0.26 5.80 13.70
>170-200 0.27 0.15 1.11 0.13 0.53 0.20 4.10 15.40

Table 2

Crop parameters"

参数
Parameter
取值
Value
灌浆到成熟的积温Thermal time start filling to mature 580
春化系数Sensitivity to vernalisation 1
光周期系数Sensitivity to photoperiod 2
最大灌浆速率Maximum grain filling rate 2.30
分蘖重Weight of tiller (g tiller-1) 1.22
单株重Weight of single plant (g) 4
株高Stem length (mm) 1000
播种期地表蒸发系数(土壤) Surface evaporation coefficient (soil) during sowing 7.20
发芽期地表蒸发系数(土壤) Surface evaporation coefficient (soil) during germination 6.20

Table 3

Different precipitation years"

年型
Model year
平均降水量
Average
precipitation
变异系数
Variable
coefficient
合计(年)
Total (year)
年份
Year
干旱年
Dry year
136.4 0.19 13 1971 1974 1975 1976 1982 1995 1997 2000
2001 2008 2009 2011 2017
平水年
Normal year
202.5 0.043 20 1972 1973 1980 1981 1983 1985 1987 1988
1989 1992 1994 1996 2002 2004 2006 2007
2010 2014 2015 2016
湿润年
Wet year
270.0 0.092 15 1977 1978 1979 1984 1986 1990 1991 1993
1998 1999 2003 2005 2012 2013 2018

Table 4

Water-nitrogen coupling simulation test"

因素Factor N1 N2 N3 N4 N5
P1 P1N1 P1N2 P1N3 P1N4 P1N5
P2 P2N1 P2N2 P2N3 P2N4 P2N5
P3 P3N1 P3N2 P3N3 P3N4 P3N5
P4 P4N1 P4N2 P4N3 P4N4 P4N5
P5 P5N1 P5N2 P5N3 P5N4 P5N5

Fig. 1

Linear regression fitting of simulated and measured values of wheat yield and biomass"

Fig. 2

Comparisons of simulated and observed wheat biomass in 2002-2009"

Fig. 3

Yield and biomass under different years of water and nitrogen treatments"

Table 5

Wheat average coefficient of variation and average sustainability index"

年型Model year Y-CV B-CV Y-SYI B-SYI
干旱年Dry year 54.72 55.97 29.08 27.98
平水年Normal year 54.99 50.94 32.00 28.88
湿润年Wet year 40.85 39.51 55.29 39.58

Fig. 4

Coefficient of variation for wheat yield in different years"

Fig. 5

Sustainability index of wheat yield in different years"

Fig. 6

3D surface map of yield under different years"

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