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Journal of Arid Land  2021, Vol. 13 Issue (8): 761-776    DOI: 10.1007/s40333-021-0015-3     CSTR: 32276.14.s40333-021-0015-3
    
Reducing water and nitrogen inputs combined with plastic mulched ridge-furrow irrigation improves soil water and salt status in arid saline areas, China
LI Cheng1,2, WANG Qingsong1,2, LUO Shuai1,2, QUAN Hao1,2, WANG Naijiang1,2, LUO Xiaoqi1,2, ZHANG Tibin1,2,3,4, DING Dianyuan5, DONG Qin'ge1,2,3,4,*(), FENG Hao1,2,3,4,*()
1 Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A&F University, Yangling 712100, China
2 College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling 712100, China
3 Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, China
4 Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, China
5 College of Hydraulic Science and Engineering, Yangzhou University, Yangzhou 225009, China
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Abstract  

Plastic mulched ridge-furrow irrigation is a useful method to improve crop productivity and decrease salt accumulation in arid saline areas. However, inappropriate irrigation and fertilizer practices may result in ecological and environmental problems. In order to improve the resource use efficiency in these areas, we investigated the effects of different irrigation amounts (400 (I1), 300 (I2) and 200 (I3) mm) and nitrogen application rates (300 (F1) and 150 (F2) kg N/hm2) on water consumption, salt variation and resource use efficiency of spring maize (Zea mays L.) in the Hetao Irrigation District (HID) of Northwest China in 2017 and 2018. Result showed that soil water contents were 0.2%-8.9% and 13.9%-18.1% lower for I2 and I3 than for I1, respectively, but that was slightly higher for F2 than for F1. Soil salt contents were 7.8%-23.5% and 48.5%-48.9% lower for I2 than for I1 and I3, but that was 1.6%-5.5% higher for F1 than for F2. Less salt leaching at the early growth stage (from sowing to six-leaf stage) and higher salt accumulation at the peak growth stage (from six-leaf to tasseling stage and from grain-filling to maturity stage) resulted in a higher soil salt content for I3 than for I1 and I2. Grain yields for I1 and I2 were significantly higher than that for I3 and irrigation water use efficiency for I2 was 14.7%-34.0% higher than that for I1. Compared with F1, F2 increased the partial factor productivity (PFP) of nitrogen fertilizer by more than 80%. PFP was not significantly different between I1F2 and I2F2, but significantly higher than those of other treatments. Considering the goal of saving water and nitrogen resources, and ensuring food security, we recommended the combination of I2F2 to ensure the sustainable development of agriculture in the HID and other similar arid saline areas.



Key wordsplastic mulched ridge-furrow irrigation      crop water consumption      soil salt variations      resource use efficiency      Hetao Irrigation District     
Received: 08 March 2021      Published: 10 August 2021
Corresponding Authors:
Cite this article:

LI Cheng, WANG Qingsong, LUO Shuai, QUAN Hao, WANG Naijiang, LUO Xiaoqi, ZHANG Tibin, DING Dianyuan, DONG Qin'ge, FENG Hao. Reducing water and nitrogen inputs combined with plastic mulched ridge-furrow irrigation improves soil water and salt status in arid saline areas, China. Journal of Arid Land, 2021, 13(8): 761-776.

URL:

http://jal.xjegi.com/10.1007/s40333-021-0015-3     OR     http://jal.xjegi.com/Y2021/V13/I8/761

Depth (cm) Clay (%) Silt (%) Sand (%) Soil texture Bulk density
(g/cm3)
Field capacity
(g/g)
EC
(dS/m)
pH
0-20 20.00 51.49 28.72 Silt loam 1.36 0.23 1.15 8.65
20-40 23.85 50.29 25.86 Silt loam 1.48 0.24 2.04 8.41
40-60 21.62 32.12 46.26 Silt loam 1.39 0.29 0.94 8.55
60-80 2.51 4.24 93.25 Sand 1.44 0.30 0.80 8.68
80-100 6.93 14.67 78.40 Sandy loam 1.47 0.29 0.73 8.65
Table 1 Soil physical and chemical properties of the study area
Growth stage of spring maize Date in 2017 Date in 2018 I1 (mm) I2 (mm) I3 (mm)
V6 31 May 28 May 100 80 60
V12 2 July 30 June 100 75 50
R1 29 July 29 July 100 75 50
R3 17 August 18 August 100 70 40
Total 400 300 200
Table 2 Irrigation date and amount in the experiment
Fig. 1 Mean air temperature, rainfall (a) and groundwater table (b) during growing seasons in 2017 and 2018. V0, sowing stage; V6, six-leaf stage; VT, tasseling stage; R3, grain-filling stage; R6, maturity stage.
Fig. 2 Soil water contents in the 0-100 cm soil depth for different irrigation and fertilizer treatments during the growing seasons in 2017 (a and b) and 2018 (c and d). I1, 400 mm irrigation; I2, 300 mm irrigation; I3, 200 mm irrigation; F1, 300 kg N/hm2; F2, 150 kg N/hm2. Arrows indicate irrigation dates. Bars indicate standard deviations.
Year Treatment Irrigation
(mm)
Water flux
(mm)
Soil water variation
(mm)
ET
(mm)
2017 I1F1 400 35.5 47.2 449a
I1F2 400 37.9 48.6 448a
I2F1 300 0.2 56.9 394b
I2F2 300 3.5 57.2 391b
I3F1 200 -1.3 62.4 301c
I3F2 200 -1.3 63.4 286c
2018 I1F1 400 93.5 40.9 460a
I1F2 400 97.2 41.8 457a
I2F1 300 10.5 57.8 460a
I2F2 300 8.1 59.1 463a
I3F1 200 -16.6 60.1 389b
I3F2 200 -7.1 57.6 377b
Table 3 Water flux, soil water variation and ET in 2017 and 2018
Year Treatment V0-V6 stages V6-VT stages VT-R3 stages R3-R6 stages
ETcs
(mm)
Q
(mm)
Kwc ETcs
(mm)
Q
(mm)
Kwc ETcs
(mm)
Q
(mm)
Kwc ETcs
(mm)
Q
(mm)
Kwc
2017 I1F1 63.5 30.8 0.141 166.5 -1.7 0.371 85.8 5.3 0.191 133.2 1.1 0.297
I1F2 60.4 30.3 0.135 164.1 -0.9 0.366 87.1 7.2 0.194 136.4 1.4 0.304
I2F1 55.0 5.2 0.140 146.0 -3.6 0.370 72.9 1.5 0.185 120.2 -2.9 0.305
I2F2 52.1 6.8 0.133 144.8 -3.0 0.370 75.8 1.4 0.194 118.3 -1.6 0.303
I3F1 41.2 4.2 0.137 112.3 -6.3 0.373 57.2 1.8 0.190 90.3 -1.1 0.300
I3F2 37.2 4.0 0.130 105.7 -6.4 0.370 55.8 2.8 0.195 87.3 -1.8 0.305
2018 I1F1 68.8 40.9 0.150 170.6 11.3 0.371 84.4 19.3 0.183 136.0 22.0 0.296
I1F2 66.4 46.0 0.145 165.6 10.4 0.362 89.8 21.9 0.197 135.2 18.9 0.296
I2F1 60.8 13.3 0.132 165.6 -4.1 0.360 92.3 3.3 0.201 141.0 -2.0 0.307
I2F2 62.3 11.0 0.135 168.9 -5.2 0.365 90.1 4.4 0.194 142.1 -2.2 0.307
I3F1 55.9 3.7 0.144 141.4 -12.1 0.363 74.9 0.9 0.193 117.0 -9.1 0.301
I3F2 53.2 3.4 0.141 139.9 -9.9 0.371 71.6 1.3 0.190 112.4 -2.0 0.298
Table 4 Water consumption (ETcs), soil water exchange (Q) and water consumption coefficient (Kwc) of spring maize during different growth stages in 2017 and 2018
Fig. 3 Soil salt contents in the 0-100 cm soil depth for different irrigation and fertilizer treatments during the growing seasons in 2017 (a and b) and 2018 (c and d). I1, 400 mm irrigation; I2, 300 mm irrigation; I3, 200 mm irrigation; F1, 300 kg N/hm2; F2, 150 kg N/hm2. Arrows indicate irrigation dates. Bars indicate standard deviations.
Year Treatment V0-R6 stages V0-V6 stages V6-VT stages VT-R3 stages R3-R6 stages
SSSw
(t/hm2)
SSSp
(t/hm2)
Kvc SSSp
(t/hm2)
Kvc SSSp
(t/hm2)
Kvc SSSp
(t/hm2)
Kvc
2017 I1F1 7.9 -29.5 -3.7 12.1 1.5 16.3 2.1 9.1 1.1
I1F2 5.4 -35.1 -6.5 11.3 2.1 17.7 3.3 11.5 2.1
I2F1 -2.0 -30.8 15.4 9.1 -4.5 12.8 -6.4 6.9 -3.4
I2F2 -4.0 -30.4 7.6 8.6 -2.1 11.3 -2.8 6.6 -1.6
I3F1 23.4 -19.6 -0.8 13.5 0.6 21.1 0.9 8.5 0.4
I3F2 25.2 -17.8 -0.7 12.6 0.5 21.0 0.8 9.4 0.4
2018 I1F1 0.7 -33.5 -47.9 11.2 16.0 14.6 20.9 8.4 12.0
I1F2 0.3 -32.2 -107.3 10.7 33.3 12.9 40.4 8.6 27.9
I2F1 -5.7 -29.1 5.1 7.9 -1.4 9.8 -1.7 5.7 -1.0
I2F2 -6.4 -28.5 4.5 7.6 -1.2 8.1 -1.3 6.4 -1.0
I3F1 18.4 -21.4 -1.2 12.8 0.7 19.6 1.1 7.5 0.4
I3F2 20.2 -18.1 -0.9 11.8 0.6 18.8 0.9 7.8 0.4
Table 5 Soil salt storage (SSSw and SSSp) and salt variation coefficient (Kvc) of spring maize during different growth stages in 2017 and 2018
Fig. 4 Dry matter accumulation for each irrigation and fertilizer treatment combination during the growing seasons in 2017 (a) and 2018 (b). I1, 400 mm irrigation; I2, 300 mm irrigation; I3, 200 mm irrigation; F1, 300 kg N/hm2; F2, 150 kg N/hm2. Bars represent standard deviations.
Year Treatment TKW
(g)
Grain yield (kg/hm2) WUE
(kg/(hm2•mm))
IWUE
(kg/(hm2•mm))
PFP
(kg/kg)
2017 I1F1 374.5a 14,678a 32.7a 36.7b 62.4bc
I1F2 383.1a 14,689a 32.8a 36.7b 124.9a
I2F1 329.5b 12,718a 32.3a 42.4ab 54.1cd
I2F2 333.3b 12,526a 32.1a 41.8ab 106.5a
I3F1 309.5b 10,275b 34.0a 51.4a 43.7d
I3F2 274.4c 9361c 32.7a 46.8ab 79.6b
2018 I1F1 377.4a 14,550a 31.6a 36.4c 61.8c
I1F2 383.0a 15,521a 34.0a 38.8c 132.0a
I2F1 371.8a 14,646a 31.9a 48.8b 62.3c
I2F2 370.6a 15,589a 33.6a 52.0b 132.6a
I3F1 358.4b 12,272b 31.5a 61.4a 52.2c
I3F2 353.8b 11,930b 31.6a 59.7a 101.4b
Table 6 Grain yield, water use efficiency (WUE), irrigation WUE (IWUE) and partial factor productivity (PFP) of nitrogen fertilizer of spring maize under different irrigation and nitrogen treatments in 2017 and 2018
Fig. 5 Relationships of water consumption coefficient (Kwc; a and b) and soil salt content (c and d) with increment of aboveground dry matter (IAGM) in 2017 and 2018
Fig. 6 Relationship between yield and soil salt content in 2017 (a) and 2018 (b)
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