Coupled dynamics of photosynthesis, transpiration and soil water balance: from hourly to growing-season time scale

As an important component of the water budget, quantifying actual crop evapotranspiration (ET) will enable better planning, management, and allocation of the water resources. However, accurate ET measurement has always been a challenging task in agricultural water management. In the upper Midwest, where subsurface drainage is a common practice due to the shallow ground water depth and heavy clayey soil, ET measurement using traditional ground-based methods is more difficult. In this study, ET was measured using the eddy covariance (EC), Bowen ratio-energy balance (BREB), and soil water balance (SWB) methods during the 2018 corn growing season, and the results of the three methods were compared. To close the energy balance for the EC system, the residual method was used. For the SWB method, capillary rise was included in the ET estimation and was calculated using the measured soil water potential. The change of soil water content for ET estimation using the SWB method was calculated in four different ways, including daily average, 24:00–2:00 average, 24:00–4:00 average, and 4:00 measurement. Through the growing season, six observation periods (OPs) with no rainfall or minimal rainfall events were selected for comparisons among the three methods. The estimated latent heat flux (LE) by the EC system using the residual method showed a 29% overestimation compared to LE determined by the BREB system for the entire growing season. After excluding data taken in May and October, LE determined by the EC system was only 10% higher, indicating that the main difference between the two systems occurred during the early and late of the growing season. By considering all six OPs, a 6%–22% LE difference between the EC and the BREB systems was observed. Except during the early growing and late harvest seasons, both systems agreed well in LE estimation. The SWB method using the average soil water contents between 24:00 and 2:00 time period to calculate the daily capillary rise produced the best statistical fit when compared to the ET estimated by the BREB, with a root-mean-square error of 1.15. Therefore, measuring ET using the capillary rise from a shallow water table between 24:00 and 2:00 could improve the performance of the SWB methodology for ET measurement.

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Coupled Dynamics of Photosynthesis, Transpiration, and Soil Water Balance. Part II: Stochastic Analysis and Ecohydrological Significance

Journal of Hydrometeorology ◽

10.1175/1525-7541(2004)005<0559:cdopta>2.0.co;2 ◽

2004 ◽

Vol 5 (3) ◽

pp. 559-566 ◽

Cited By ~ 34

Author(s):

Edoardo Daly ◽

Amilcare Porporato ◽

Ignacio Rodriguez-Iturbe

Keyword(s):

Water Balance ◽

Soil Water ◽

Stochastic Analysis ◽

Soil Water Balance ◽

Coupled Dynamics

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Estimation of Soil Water Balance Components Based on Continuous Soil Moisture Measurement and Inversed Richards Method in an Irrigated Agricultural Field of a Desert Oasis

10.5194/egusphere-egu2020-6274 ◽

2020 ◽

Author(s):

Hu Liu ◽

Yang Yu ◽

Zhongkai Li ◽

Wenzhi Zhao ◽

Qiyue Yang ◽

...

Keyword(s):

Soil Moisture ◽

Water Balance ◽

Soil Water ◽

Estimation Method ◽

Growing Season ◽

Soil Water Balance ◽

Richards Equation ◽

Water Balance Components ◽

Sustainable Water Resources Management ◽

Irrigation Drainage

An accurate assessment of soil water balance components (SWBCs) is necessary for improving irrigation strategies in any water-limited environment. However, quantitative information of SWBCs is usually challenging to obtain, because none of the components (i.e., irrigation, drainage, and evapotranspiration) can be easily measured under actual conditions. Soil moisture is a variable that integrates the water balance components of land surface hydrology, and the evolution of soil moisture is assumed to contain the memory of antecedent hydrologic fluxes, and thus can be used to determine SWBCs from a hydrologic balance. A database of&#160;soil&#160;moisture&#160;measurements from six experimental plots with different treatments in the middle Heihe River Basin of China was used to test the potential of a soil moisture database in estimating the SWBCs. We first compared the hydrophysical properties of the soils in these plots, such as vertical saturated hydraulic conductivity (Ks) and soil water retention features, for supporting the SWBC estimations. Then we determined evapotranspiration and other SWBCs through a method that combined the soil water balance method and the inverse Richards equation (a model of unsaturated soil water flow based on the Richards equation). To test the accuracy of our estimation, we used both indirect methods (such as power consumption of the pumping irrigation well, and published SWBCs values at nearby sites), and the water balance equation technique to verify the estimated SWBCs values, all of which showed a good reliability of our estimation method. Finally, the uncertainties of the proposed methods were analyzed to evaluate the systematic error of the SWBC estimation and any restrictions on its application. The results showed significant variances among the film-mulched plots in both the cumulative irrigation volumes (652.1~ 867.3 mm) and deep drainages (170.7~364.7 mm). Moreover, the unmulched plot had remarkably higher values in both cumulative irrigation volumes (1186.5 mm) and deep drainages (651.8 mm) compared with the mulched plots. Obvious correlation existed between the volume of irrigation and that of drained water. However, the ET demands for all the plots behaved pretty much the same, with the cumulative ET values ranging between 489.1 and 561.9 mm for the different treatments in 2016, suggesting that the superfluous irrigation amounts had limited influence on the accumulated ET throughout the growing season because of the poor water-holding capacity of the sandy soil. This work confirmed that relatively reasonable estimations of the SWBCs in coarse-textured sandy soils can be derived by using soil moisture measurements; the proposed methods provided a reliable solution over the entire growing season and showed a great potential for identifying appropriate irrigation amounts and frequencies, and thus a move toward sustainable water resources management, even under traditional surface irrigation conditions.

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Quantification of soil water balance components based on continuous soil moisture measurement and the Richards equation in an irrigated agricultural field of a desert oasis

Hydrology and Earth System Sciences ◽

10.5194/hess-23-4685-2019 ◽

2019 ◽

Vol 23 (11) ◽

pp. 4685-4706 ◽

Cited By ~ 2

Author(s):

Zhongkai Li ◽

Hu Liu ◽

Wenzhi Zhao ◽

Qiyue Yang ◽

Rong Yang ◽

...

Keyword(s):

Soil Moisture ◽

Water Balance ◽

Soil Water ◽

Estimation Method ◽

Growing Season ◽

Soil Water Balance ◽

Richards Equation ◽

Water Balance Components ◽

Sustainable Water Resources Management ◽

Irrigation Drainage

Abstract. An accurate assessment of soil water balance components (SWBCs) is necessary for improving irrigation strategies in any water-limited environment. However, quantitative information on SWBCs is usually challenging to obtain, because none of the components (i.e., irrigation, drainage, and evapotranspiration) can be easily measured under actual conditions. Soil moisture is a variable that integrates the water balance components of land surface hydrology, and the evolution of soil moisture is assumed to contain the memory of antecedent hydrologic fluxes, and can thus be used to determine SWBCs from a hydrologic balance. A database of soil moisture measurements from six experimental plots with different treatments in the middle Heihe River basin of China was used to test the potential of a such a database for estimating SWBCs. We first compared the hydrophysical properties of the soils in these plots, such as vertical saturated hydraulic conductivity (Ks) and soil water retention features, for supporting SWBC estimations. We then determined evapotranspiration and other SWBCs using a method that combined the soil water balance method and the inverse Richards equation (a model of unsaturated soil water flow based on the Richards equation). To test the accuracy of our estimation, we used both indirect methods (such as power consumption of the pumping irrigation well and published SWBCs values at nearby sites) and the water balance equation technique to verify the estimated SWBCs values, all of which showed good reliability with respect to our estimation method. Finally, the uncertainties of the proposed methods were analyzed to evaluate the systematic error of the SWBC estimation and any restrictions regarding its application. The results showed significant variances among the film-mulched plots in both the cumulative irrigation volumes (652.1–867.3 mm) and deep drainages (170.7–364.7 mm). Moreover, the un-mulched plot had remarkably higher values in both cumulative irrigation volumes (1186.5 mm) and deep drainages (651.8 mm) compared with the mulched plots. Obvious correlation existed between the volume of irrigation and that of drained water. However, the ET demands for all of the plots behaved pretty much the same, with the cumulative ET values ranging between 489.1 and 561.9 mm for the different treatments in 2016, suggesting that the superfluous irrigation amounts had limited influence on the accumulated ET throughout the growing season due to the poor water-holding capacity of the sandy soil. This work confirmed that relatively reasonable estimations of the SWBCs in coarse-textured sandy soils can be derived by using soil moisture measurements; the proposed methods provided a reliable solution over the entire growing season and showed a great potential for identifying appropriate irrigation amounts and frequencies, and thus a move toward sustainable water resources management, even under traditional surface irrigation conditions.

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The soil water balance and the development of spring soft wheat under various cultivation technologies

Ukrainian Journal of Ecology ◽

10.15421/2019_817 ◽

2019 ◽

Vol 9 (4) ◽

pp. 723-728 ◽

Cited By ~ 1

Author(s):

V. I. Belyaev ◽

M. M. Silanteva ◽

A. V. Matsyura ◽

L. V. Sokolova

Keyword(s):

Soil Moisture ◽

Water Balance ◽

Soil Water ◽

Water Consumption ◽

Soil Layer ◽

Growing Season ◽

Vegetation Period ◽

Soil Water Balance ◽

Soft Wheat ◽

Spring Soft Wheat

The steppe zone has always attracted people with its resources, despite the fact that it is a zone of risky agriculture. In this research we discovered that soil water balance under the spring soft wheat was negative most of the time of the vegetation period in the Rebrikhinsky district of the Altai Region, and soil moisture consumption during the observation period depends on the technology options and an average values was in the range from 100.9 mm to 131.9 mm. An average soil moisture consumption was 42.5% of spring moisture reserves. In the plots where autumn soil cultivation was not carried out, the average water consumption for the vegetation period was 41.7% of the spring moisture reserves, while in those plots where it was 43.2%, i.e., only 1.5% more. The absence of both autumn and spring tillage led to the consumption of 38.8% moisture from spring soil moisture reserves during the growing season. In the case when only spring tillage was carried out, this value was 44.7%, and if both cultivations were carried out - 43.2%. The difference in the sowing rates practically did not affect the total moisture consumption from the soil, it amounted to 42.2-42.8% of the spring moisture reserves. The maximum difference in water consumption was found when comparing the equipment used for spring tillage and sowing. So, when using Catros and DMC-9000, respectively, an average of 47.5% of spring moisture reserves was spent during the growing season, while using Russian-made equipment – KPE-3,8 or BDM-6*4 and SZP-3.6А, it was 38.9%. The moisture reserves in the meter soil layer decreased in direct proportion to the increase in average plant height.

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Soil water balance simulated by CROPGRO-Drybean model for edaphoclimatic conditions in Maringá

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/s1415-43662010000400002 ◽

2010 ◽

Vol 14 (4) ◽

pp. 351-357 ◽

Cited By ~ 5

Author(s):

Rivanildo Dallacort ◽

Paulo S. L. de Freitas ◽

Rogério T. de Faria ◽

Antonio C. A. Gonçalves ◽

Aleksandra G. Jácome ◽

...

Keyword(s):

Soil Moisture ◽

Water Balance ◽

Soil Water ◽

Crop Yield ◽

Field Experiments ◽

Growing Season ◽

Soil Water Balance ◽

State University ◽

Using Data ◽

Bean Crop

The performance of the CROPGRO-Drybeans model for the prediction of soil water balance, as well as growth components and bean crop yield, was assessed using data from two field experiments conducted at the State University of Maringá Irrigation Technical Center, Paraná - Brazil, (latitude 23º27'S, longitude 51º57' and altitude 542 m), during the 2005 and 2006 growing season. The model simulations correlated well with measured soil moisture (r > 0.7) for both experiments. However, there were high discrepancies between measured and simulated soil moisture values on the days after rainfall. In addition, it was found that the model exaggerates the effect of water stress during the flowering phase, which leds to underprediction (19 and 29%) of crop yield.

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