Optimizing parameters of salinity stress reduction function using the relationship between root-water-uptake and root nitrogen mass of winter wheat

2012 ◽  
Vol 104 ◽  
pp. 142-152 ◽  
Author(s):  
Lichun Wang ◽  
Jianchu Shi ◽  
Qiang Zuo ◽  
Wenjuan Zheng ◽  
Xiangming Zhu
Keyword(s):  
Winter Wheat ◽  
Water Uptake ◽  
Salinity Stress ◽  
Stress Reduction ◽  
Root Water Uptake ◽  
Reduction Function ◽  
The Relationship ◽  
Root Nitrogen

scholarly journals Root-Water-Uptake Based upon a New Water Stress Reduction and an Asymptotic Root Distribution Function

2006 ◽  
Vol 10 (14) ◽  
pp. 1-22 ◽  
Author(s):  
K. Y. Li ◽  
R. De Jong ◽  
M. T. Coe ◽  
N. Ramankutty
Keyword(s):  
Distribution Function ◽  
Water Stress ◽  
Water Uptake ◽  
Stress Reduction ◽  
Land Surface ◽  
Root Distribution ◽  
Large Scale ◽  
Water Pressure ◽  
Root Water Uptake ◽  
Reduction Function

Abstract A water stress–compensating root-water-uptake module was developed based upon a newly proposed water stress reduction function and an asymptotic root distribution function. The water stress reduction function takes into account both soil water pressure head and soil resistance to water flow. It requires only physically based parameters that eliminate the need for empirical calibration. The root-water-uptake module, incorporated into a complete Soil–Vegetation–Atmosphere Transfer (SVAT) simulation model, was tested for a variety of soil, crop, and climatic conditions across Canada. Both the proposed water stress reduction and the asymptotic root distribution function performed similarly to existing ones, with the maximum difference in normalized root-mean-square error (NRMSE) between the new and existing water stress reduction function being 0.6%, and between the asymptotic and an exponential root distribution function being 1.2%. The entire root-water-uptake module worked as well as, or better than, published ones. Because the new module uses fewer empirical parameters, it becomes particularly useful in large-scale modeling applications of land surface, hydrology, and terrestrial ecosystems where such parameters are usually not readily available.

Comparison of Spring Maize Root Water Uptake Models Under Water and Salinity Stress Validated with Field Experiment Data

2015 ◽  
Vol 64 (5) ◽  
pp. 669-682 ◽  
Author(s):  
Qingming Wang ◽  
Zailin Huo ◽  
Shaoyuan Feng ◽  
Chengfu Yuan ◽  
Jianhua Wang
Keyword(s):  
Field Experiment ◽  
Water Uptake ◽  
Salinity Stress ◽  
Root Water Uptake ◽  
Maize Root ◽  
Experiment Data ◽  
Spring Maize

scholarly journals Seasonal Variations in Water Uptake Patterns of Winter Wheat under Different Irrigation and Fertilization Treatments

Water ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1633 ◽  
Author(s):  
Ying Ma ◽  
Xianfang Song
Keyword(s):  
Winter Wheat ◽  
Water Uptake ◽  
Water Cycle ◽  
Negative Relationship ◽  
Root Water Uptake ◽  
Severe Drought ◽  
Root Characteristics ◽  
Irrigation Water Use ◽  
Jointing Stage ◽  
Heading Stage

Irrigation and fertilization both affect the water cycle in agricultural ecosystems. It is difficult to quantify root water uptake (RWU) which varies with crop development and seasons. In this study, a Bayesian mixing model (MixSIAR) coupling with dual stable isotopes (D and 18O) was used to quantify RWU patterns for winter wheat under different irrigation and fertilization treatments between 2014 and 2015 in Beijing, China. The main RWU depth during the greening-jointing, jointing-heading, heading-filling, and filling-harvest stages was 0–20 cm, 20–70 cm, 0–20 cm, and 20–70 cm, respectively, which showed water uptake proportions of 67.0%, 42.0%, 38.7%, and 34.9%, respectively. Significant differences in RWU patterns appeared between the 2014 and 2015 seasons. The main RWU depth increased gradually from 0–20 cm at the greening-jointing stage to 20–70 cm at the jointing-heading stage and 70–150 cm during the heading to harvest period in 2014. However, winter wheat primarily took up soil water from the 0–70 cm layer in 2015. The average water uptake proportion in the top layer (0–20 cm) in 2015 (42.6%) was remarkably higher than that in 2014 (28.7%). There was a significantly negative relationship (p < 0.01) between the water uptake proportion and the proportion of root length at the filling-harvest stage in 2014, while no significant correlation (p > 0.05) was found in 2015. Variable distributions of root characteristics and soil moisture induced by different irrigation and fertilization comprehensively affected the RWU profile, particularly under severe drought environments in 2015. Treatments with fertilization of 105 kg hm−2 N or irrigation of 20 mm during the greening-jointing stage significantly promoted water uptake contribution in the 70–150 cm (32.2%) and 150–200 cm (23.5%) layers at the jointing-heading stage in 2015, while other treatments had a shallow dominant RWU depth (0–20 cm). The planned wetting layer should be kept within the main RWU depth of 0–70 cm for improving irrigation water use efficiency.

Using stable isotopes to quantify root water uptake under a new planting pattern of high-low seed beds cultivation in winter wheat

2021 ◽  
Vol 205 ◽  
pp. 104816
Author(s):  
Junming Liu ◽  
Zhuanyun Si ◽  
Lifeng Wu ◽  
Jinsai Chen ◽  
Yang Gao ◽  
...  
Keyword(s):  
Stable Isotopes ◽  
Winter Wheat ◽  
Water Uptake ◽  
Root Water Uptake ◽  
Planting Pattern

Parameter Estimation of a Root Water Uptake Model under Salinity Stress

2008 ◽  
Vol 7 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Haruyuki Fujimaki ◽  
Yoshitake Ando ◽  
Yibin Cui ◽  
Mitsuhiro Inoue
Keyword(s):  
Parameter Estimation ◽  
Water Uptake ◽  
Salinity Stress ◽  
Root Water Uptake

scholarly journals Simulation of the Water Dynamics and Root Water Uptake of Winter Wheat in Irrigation at Different Soil Depths

Water ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 1033 ◽  
Author(s):  
Xianghong Guo ◽  
Xihuan Sun ◽  
Juanjuan Ma ◽  
Tao Lei ◽  
Lijian Zheng ◽  
...  
Keyword(s):  
Winter Wheat ◽  
Soil Water ◽  
Water Uptake ◽  
Water Movement ◽  
Soil Depth ◽  
Root Water Uptake ◽  
Model Verification ◽  
Water Dynamics ◽  
Soil Layers ◽  
Soil Water Movement

Soil water content (SWC) distribution plays an important role in root water uptake (RWU) and crop yield. Reasonable deep irrigation can increase the yield of winter wheat. The soil water movement model of winter wheat was established by considering the root water uptake and the different soil depths of irrigation and using the source term of the soil water movement equation to simulate irrigation at different soil depths. For model verification, experiments on three treatments of winter wheat growth were conducted at irrigation soil depths of 0% (T1), 40% (T2), and 70% (T3) of the distribution depth of the winter wheat root system. The SWC calculated by the model is in accordance with the dynamic change trend of the measured SWC. The maximum absolute error of the model was 0.022 cm3/cm3. The maximum average relative error was 7.95%. The maximum root mean square error was 0.28 cm3/cm3. Therefore, the model has a high simulation accuracy and can be used to simulate the distribution and dynamic changes of SWC of winter wheat in irrigation at different soil depths. The experimental data showed that irrigation soil depth has a significant effect on the root distribution of winter wheat (p < 0.05), and deep irrigation can reduce the root length density (RLD) in the upper soil layers and increase the RLD in the deeper soil layers. The dynamic simulation of RWU and SWC showed that deep irrigation can increase the SWC and RWU in deep soil and decrease the SWC and RWU in upper soil. Consequently, deep irrigation can increase the transpiration of winter wheat, reduce evaporation and evapotranspiration, and increase the yield of winter wheat.

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