Impact of saline water irrigation on water use efficiency and soil salt accumulation for spring maize in arid regions of China

ABSTRACT In Northeast Brazil, the cultivation of colored fiber cotton has stood out as one of the agricultural activities of expressive importance because its fiber has various applications in the industry and it is a labor-demanding crop. In this context, this study aimed to evaluate the growth, water consumption, water use efficiency and production of the colored fiber cotton cv. ‘BRS Rubi’, as a function of saline water irrigation and nitrogen (N) doses. The experiment was conducted in lysimeters, under greenhouse conditions, in eutrophic Regolithic Neosol, with a sandy loam texture, in Campina Grande-PB, Brazil. The plants were irrigated using water with electrical conductivities (ECw) of 5.1, 6.1, 7.1, 8.1 and 9.1 dS m-1 and fertilized with N doses (ND) of 65, 100, 135, 170 and 205 mg N kg-1 soil, in a completely randomized block design, with three replicates. Irrigation using water with an ECw above 5.1 dS m-1, hampered growth, water consumption and water use efficiency of ‘BRS Rubi’ cotton. Among the organs, the cotton root system was less affected by the salt stress in comparison to the shoots. N fertilization did not mitigate the deleterious effect of salt stress on cotton growth, water consumption, water use efficiency and production. The interaction between water salinity and N fertilization had positive effects on total weight of seeds and lint, and the highest values were obtained in plants irrigated with water of ECw 7.6 and 7.5 dS m-1 and ND of 65 mg N kg-1 of soil.

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Spatial–Temporal Evolution Characteristics and Influencing Factors of Agricultural Water Use Efficiency in Northwest China—Based on a Super-DEA Model and a Spatial Panel Econometric Model

Water ◽

10.3390/w13050632 ◽

2021 ◽

Vol 13 (5) ◽

pp. 632

Author(s):

Weinan Lu ◽

Wenxin Liu ◽

Mengyang Hou ◽

Yuanjie Deng ◽

Yue Deng ◽

...

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

Water Resource ◽

Arid Regions ◽

Econometric Model ◽

Northwest China ◽

Agricultural Water ◽

Agricultural Water Use ◽

Use Efficiency ◽

Semi Arid

Improving agricultural water use efficiency (AWUE) is an important way to solve the shortage of water resources in arid and semi-arid regions. This study used the Super-DEA (data envelopment analysis) to measure the AWUE of 52 cities in Northwest China from 2000 to 2018. Based on spatial and temporal perspectives, it applied Exploratory Spatial Data Analysis (ESDA) to explore the dynamic evolution and regional differences of AWUE. A spatial econometric model was then used to analyze the main factors that influence the AWUE in Northwest China. The results showed firstly that the overall AWUE in Northwest China from 2000 to 2018 presented a steady upward trend. However, only a few cities achieved effective agricultural water usage by 2018, and the differences among cities were obvious. Secondly, AWUE showed an obvious spatial autocorrelation in Northwest China and showed significant high–high and low–low agglomeration characteristics. Thirdly, economic growth, urbanization development, and effective irrigation have significant, positive effects on AWUE, while per capita water resource has a significant, negative influence. Finally, when improving the AWUE in arid and semi-arid regions, plans should be formulated according to local conditions. The results of this study can provide new ideas on the study of AWUE in arid and semi-arid regions and provide references for the formulation of regional agricultural water resource utilization policies as well.

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