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פותח על ידי קלירמאש פתרונות בע"מ -
Introducing water stress hysteresis to the Feddes empirical macroscopic root water uptake model
Year:
2020
Source of publication :
Agricultural Water Management
Authors :
בן-גל, אלון
;
.
Volume :
240
Co-Authors:

Wu, X. - College of Water Resources and Civil Engineering, China Agricultural University, Beijing, 100083, China.
Zuo, Q.- College of Land Science and Technology, China Agricultural University, Key Laboratory of Plant-Soil Interactions, Ministry of Education, Key Laboratory of Arable Land Conservation (North China), Ministry of Agriculture, Beijing, 100193, China.
 Shi, J. - College of Land Science and Technology, China Agricultural University, Key Laboratory of Plant-Soil Interactions, Ministry of Education, Key Laboratory of Arable Land Conservation (North China), Ministry of Agriculture, Beijing, 100193, China.
 Wang, L. - National Research Center of Intelligent Equipment for Agriculture, Beijing, 100097, China.
Xue, X. - National Research Center of Intelligent Equipment for Agriculture, Beijing, 100097, China.

Facilitators :
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Total pages:
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Abstract:

During wetting-drying cycles, divergence is often found between the immediately improved soil water conditions after re-watering and the recovery of plant water status from stress, which ensues only gradually. Such an apparent hysteresis effect of water stress (HEWS) is usually neglected in simulating root-water-uptake (RWU) by empirical models. To consider HEWS in the empirical macroscopic RWU model of Feddes, a water stress recovery coefficient (δ) was introduced based on two lysimetric experiments under greenhouse and field conditions for winter wheat. The integrated effects of historical water stress events were investigated by assuming that the normalized influence weight of each past stress event declines with the increase of time interval before simulation as an exponential function of attenuation rate. Although δ could be described by an exponential function of an integrative index representing the general historical stress extent (R2 = 0.65, P < 0.001), with an attenuation rate smaller than 0.13, it is challenging to establish such a function practically. An attenuation rate close to zero means HEWS is mainly dominated by the water stress on the previous day, validated by a significant relationship between the relative transpiration or stomatal conductance on the day after irrigation and the water stress extent on the day before irrigation. Therefore, a simplification, substituting the integrative index in the exponential function with the stress extent on the previous day, was proposed for estimating δ. Compared to the traditional RWU model, the revised model considering HEWS was more successful in simulating relative transpiration and soil water dynamics. Root mean square error of relative transpiration was reduced by 65.9 % and of soil water by 30 % in the greenhouse experiment and by 7.4 % and 12.5 %, respectively, in the field experiment.

Note:
Related Files :
greenhouses
irrigation
Mean square error
Stomatal conductance
transpiration
Triticum aestivum
water stress
עוד תגיות
תוכן קשור
More details
DOI :
10.1016/j.agwat.2020.106293
Article number:
0
Affiliations:
Database:
גוגל סקולר
Publication Type:
מאמר
;
.
Language:
אנגלית
Editors' remarks:
ID:
48350
Last updated date:
02/03/2022 17:27
Creation date:
21/06/2020 18:03
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Scientific Publication
Introducing water stress hysteresis to the Feddes empirical macroscopic root water uptake model
240

Wu, X. - College of Water Resources and Civil Engineering, China Agricultural University, Beijing, 100083, China.
Zuo, Q.- College of Land Science and Technology, China Agricultural University, Key Laboratory of Plant-Soil Interactions, Ministry of Education, Key Laboratory of Arable Land Conservation (North China), Ministry of Agriculture, Beijing, 100193, China.
 Shi, J. - College of Land Science and Technology, China Agricultural University, Key Laboratory of Plant-Soil Interactions, Ministry of Education, Key Laboratory of Arable Land Conservation (North China), Ministry of Agriculture, Beijing, 100193, China.
 Wang, L. - National Research Center of Intelligent Equipment for Agriculture, Beijing, 100097, China.
Xue, X. - National Research Center of Intelligent Equipment for Agriculture, Beijing, 100097, China.

Introducing water stress hysteresis to the Feddes empirical macroscopic root water uptake model

During wetting-drying cycles, divergence is often found between the immediately improved soil water conditions after re-watering and the recovery of plant water status from stress, which ensues only gradually. Such an apparent hysteresis effect of water stress (HEWS) is usually neglected in simulating root-water-uptake (RWU) by empirical models. To consider HEWS in the empirical macroscopic RWU model of Feddes, a water stress recovery coefficient (δ) was introduced based on two lysimetric experiments under greenhouse and field conditions for winter wheat. The integrated effects of historical water stress events were investigated by assuming that the normalized influence weight of each past stress event declines with the increase of time interval before simulation as an exponential function of attenuation rate. Although δ could be described by an exponential function of an integrative index representing the general historical stress extent (R2 = 0.65, P < 0.001), with an attenuation rate smaller than 0.13, it is challenging to establish such a function practically. An attenuation rate close to zero means HEWS is mainly dominated by the water stress on the previous day, validated by a significant relationship between the relative transpiration or stomatal conductance on the day after irrigation and the water stress extent on the day before irrigation. Therefore, a simplification, substituting the integrative index in the exponential function with the stress extent on the previous day, was proposed for estimating δ. Compared to the traditional RWU model, the revised model considering HEWS was more successful in simulating relative transpiration and soil water dynamics. Root mean square error of relative transpiration was reduced by 65.9 % and of soil water by 30 % in the greenhouse experiment and by 7.4 % and 12.5 %, respectively, in the field experiment.

Scientific Publication
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