TY - JOUR
T1 - Spatial distribution of soil moisture, soil salinity, and root density beneath a cotton field under mulched drip irrigation with brackish and fresh water
AU - Chen, Wenling
AU - Jin, Menggui
AU - Ferré, Ty P.A.
AU - Liu, Yanfeng
AU - Xian, Yang
AU - Shan, Tianrui
AU - Ping, Xue
N1 - Funding Information:
This study was supported by the National Natural Science Foundation of China ( 41172218 , U1403282 and 41572224 ) and the Fundamental Research Funds for the Central Universities , China University of Geosciences (Wuhan) ( CUG170103 ). We gratefully thank the Bazhou Experimental Station of Irrigation , Xinjiang for providing facilities and housing. We sincerely thank Dr. Jinou Huang, Dr. Jianjun Wang, Mr. Liming Wang, Mr. Alim. Kasim and Miss Mengran Lin for their field and laboratory assistance and Dr. Xianwen Li for his suggestions on this paper.
Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2018/1
Y1 - 2018/1
N2 - Root systems play a vital role in soil-plant interactions. The dynamics and distributions of soil moisture content (SMC), soil salinity, and cotton (Gossypium hirsutum L.) root density under mulched drip irrigation are complex and their interactions are not well understood. The aim of this study is to describe these dynamics and distributions and to evaluate their impacts on cotton above-ground growth and yield during two-year field experiments in a cotton field under mulched drip irrigation with brackish and fresh water. Significant differences were observed for the distributions of SMC, soil salinity, and root length density (RLD) in the root zone for brackish water irrigation treatment (BWT) and fresh water irrigation treatment (FWT). The average SMC and soil salinity in the root zone were higher for BWT than for FWT. The spacing of irrigation lines also had measurable impacts. SMC was less variable when irrigation spacing was small (narrow rows) than beneath wide rows. SMC for BWT and FWT decreased after irrigation due to root water uptake; simultaneously, salt concentration increased, especially in regions where RLD was relatively high. More roots were observed growing in the mulched narrow and wide rows than in the no-mulch zone. Roots were concentrated in the shallowest 30 cm. Our study indicated that the average values of the ECe (electrical conductivity of soil saturation extract) in the root zone after BWT irrigation were higher than the published threshold value for optimal cotton yield. The average RLD, shoot dry weight and yield for BWT were observed to be lower than those of FWT as a result of the elevated soil salinity associated with BWT.
AB - Root systems play a vital role in soil-plant interactions. The dynamics and distributions of soil moisture content (SMC), soil salinity, and cotton (Gossypium hirsutum L.) root density under mulched drip irrigation are complex and their interactions are not well understood. The aim of this study is to describe these dynamics and distributions and to evaluate their impacts on cotton above-ground growth and yield during two-year field experiments in a cotton field under mulched drip irrigation with brackish and fresh water. Significant differences were observed for the distributions of SMC, soil salinity, and root length density (RLD) in the root zone for brackish water irrigation treatment (BWT) and fresh water irrigation treatment (FWT). The average SMC and soil salinity in the root zone were higher for BWT than for FWT. The spacing of irrigation lines also had measurable impacts. SMC was less variable when irrigation spacing was small (narrow rows) than beneath wide rows. SMC for BWT and FWT decreased after irrigation due to root water uptake; simultaneously, salt concentration increased, especially in regions where RLD was relatively high. More roots were observed growing in the mulched narrow and wide rows than in the no-mulch zone. Roots were concentrated in the shallowest 30 cm. Our study indicated that the average values of the ECe (electrical conductivity of soil saturation extract) in the root zone after BWT irrigation were higher than the published threshold value for optimal cotton yield. The average RLD, shoot dry weight and yield for BWT were observed to be lower than those of FWT as a result of the elevated soil salinity associated with BWT.
KW - Brackish water
KW - Irrigation water use efficiency
KW - Root length density
KW - Soil moisture
KW - Soil salinity
KW - Soil-root interactions
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U2 - 10.1016/j.fcr.2017.10.019
DO - 10.1016/j.fcr.2017.10.019
M3 - Article
AN - SCOPUS:85033500182
SN - 0378-4290
VL - 215
SP - 207
EP - 221
JO - Field Crops Research
JF - Field Crops Research
ER -