Wetting Drying Research Articles

Comments on: Correlations Between Slake-Durability Index and Engineering Properties of Some Travertine Samples Under Wetting–Drying Cycles by Davood Fereidooni and Reza Khajevand, Geotechnical and Geological Engineering (2018) 36:1071–1089

Comments on: Correlations Between Slake-Durability Index and Engineering Properties of Some Travertine Samples Under Wetting–Drying Cycles by Davood Fereidooni and Reza Khajevand, Geotechnical and Geological Engineering (2018) 36:1071–1089

Influence of wetting–drying cycles on swell–shrink behaviour of GPA-reinforced expansive clay beds

ABSTRACT Granular pile-anchor (GPA) technique is an innovative tension-resistant foundation technique which can effectively ward off the dual swell–shrink problem posed by expansive clays. The other tension-resistant foundation techniques are drilled piers, belled piers and under-reamed piles. Laboratory scale model studies and field scale experiments on GPAs revealed that swelling of expansive clay beds could be effectively controlled by GPA technique. This paper presents results obtained from laboratory scale model studies on GPA-reinforced expansive clay beds subjected to alternate cycles of wetting and drying. Swelling and shrinkage of the clay beds were monitored for three wetting–drying cycles (N) spanning a time period of 300 days. The clay beds were reinforced with varying number of GPAs (n = 0, 1, 2 and 3). Swelling (mm) and shrinkage (mm) of the clay beds in a given wetting–drying cycle decreased with increasing number of GPAs. Further, swelling (mm) and shrinkage (mm) significantly decreased with increasing number of wetting–drying cycles (N) also. For a given number of GPAs (n), swelling and shrinkage decreased with increase in depth from the top of the clay bed too.

Impact of Wetting-Drying Cycles on the Mechanical Properties and Microstructure of Wood Waste-Gypsum Composites.

Large amounts of wood waste are generated each year in the world. In an attempt to identify a good recovery option for those residues, wood waste from construction and demolition works were used as raw materials in gypsum plasters. However, wood is a biodegradable material which implies that the products or materials that contain it are susceptible to suffering an important deterioration, due to exposure in certain environments. For that reason, the aim of this work was to simulate the effects that, in the long term, the atmospheric exposure of wood waste–gypsum composites would have. To do that, the plasters were subjected to 5, 10, and 15 wetting–drying cycles in a climatic chamber. In this study, the density, flexural and compressive strength, and ultrasonic velocity of these composites were determined by the influence of the aging process on their mechanical properties. Furthermore, in order to detect changes on their internal structure, scanning electron microscopy tests (SEM) were used. The results showed that they were suitable to be used as indoor coverings of buildings. However, a treatment to reduce the moisture absorption of the wood waste must be studied if mixtures with high percentages of wood shavings (WS20) are used in wet rooms.

Unsaturated hydraulic properties of vegetated soil under single and mixed planting conditions

Effects of plant roots on changes of soil hydraulic properties, including soil water retention curves (SWRC) and soil hydraulic conductivity functions (SHCF), are not well understood, especially when soil is unsaturated and vegetated with multiple plant species. The aim of this note is to quantify the root effects on both SWRC and SHCF of silty sand using the instantaneous profile method. Four types of vegetated soil, namely bare, grass-only, tree-only and mixed tree–grass silty sand, were subjected to a controlled drying–wetting cycle in a plant room. Plant roots affect the air-entry value, saturated hydraulic conductivity and reduction rate of unsaturated hydraulic conductivity (with respect to suction) most significantly, but the roots do not affect the reduction rate of volumetric water content much. When planted with single species (grass or tree), the air-entry value of silty sand increased, while the saturated hydraulic conductivity and reduction rate of unsaturated hydraulic conductivity with suction decreased. However, under the mixed planting conditions, opposite results are found.

Response of Grain Quality to Alternate Wetting and Moderate Soil Drying Irrigation in Rice

Alternate wetting and moderate soil drying irrigation (WMD) has been widely adopted in rice (Oryza sativa L.) production for saving irrigation water and increasing grain yield. However, limited information is available about the effect of WMD on rice grain quality. The main purpose of this study was to evaluate the characteristics of grain quality in response to WMD. Two rice varieties, Yangdao 6 (YD6, indica) and Hanyou 8 (HY8, japonica), were grown in the field, with two water management treatments, well‐watered (WW) and WMD from 10 d after transplanting to maturity. In comparison with WW, WMD prominently increased grain yield by 7.57 to 9.72%, and improved some grain quality parameters such as milling, appearance, and eating and cooking qualities, including increases in head rice and decreases in chalkiness. The two varieties showed the same tendency. However, WMD had a negative impact on some nutritional quality traits in rice grains, such as reduction in the contents of amino acids and the micronutrient elements Cu, Fe, Mn, Mo, Se, and Zn. The WMD treatment also markedly decreased As content and exhibited no significant effect on Cd content in grains. The results demonstrated that WMD has an overall impact on rice grain quality with both positive and negative effects.

ERT and salinity – A method to determine whether ERT-detected preferential pathways in brackish water-irrigated soils are water-induced or an artifact of salinity

The identification of preferential flow generation and the tracking of their pathways in agricultural soils are challenging tasks, in particular while keeping the soil profile undisturbed. The noninvasive electrical resistivity tomography (ERT) method seems, a priori, to be an ideal tool for these purposes, but the simultaneous dependence of soil electrical resistivity (ER) on soil moisture content and salt concentration poses a problem when high-salinity water is involved. The dependence of these variables is expressed, for example, by Archie’s law. Irrigation with brackish or treated wastewater are two such complicated cases. The latter has been found to render soils water-repellent with inherent flow in preferential pathways. A method that resolves this complication is developed and applied for in-situ-measured ERT data. This method combines a model that simulates the preferential ER(t) as a series of interconnected well-mixed units (WMUs) with frequent ERT scans during soil wetting and subsequent drying. Following validation by comparison of its output to simulations using the Richards equation for flow and convection-dispersion equation for transport, the WMU model was used to simulate scenarios of simultaneous variations in moisture content, salinity, and ER(t) in a well-mixed soil volume (unit). The characteristic patterns acquired by these simulations were compared with in-situ measured ER(z,t) to determine whether the observed preferential ER pathways coincide with preferential flow or salinity pathways, or both. From the eight sections in the profile where this analysis was made for, five exhibit preferential flow, characterized by fast wetting front propagation that includes by-passing of a certain soil volume, while the wetting front velocity in the other three was moderate. We, therefore, concluded, based on the water content/salinity effect on ER, that the measured preferential ER pathways coincide with preferential flow pathways. Salinity has, for the current case, a minor, if any, effect on the ER spatial variation. Therefore, ERT is an advantageous mean of mapping of preferential flow pathways in the soil profile, and the method developed herein can be used for studying the water distribution in the soil profile. Particular irrigation design and management can be then used to ease the negative effects of preferential flow pathways on soil water availability to plant roots and the enhanced leaching of agrochemical below the active root zone.

Investigation of infiltration rate for soil-biochar composites of water hyacinth

The objective of this short communication is to investigate the interactive effects of CIF, suction and volumetric water content (VWC) on infiltration rate for compacted soil–biochar (BC) composites (0%, 5% and 10%). The biochar was produced from an invasive weed Eichhornia crassipes. Soil parameters such as suction (ψ), VWC, CIF and infiltration rate were monitored simultaneously for 63 days (9 drying–wetting cycles) in those composites. This was followed by statistical modeling using artificial neural networks. Results showed that increase in WH BC content reduced the infiltration rates. The role of CIF in determining the infiltration rate reduced (50–38%) with the addition of BC to soil. Suction played an equal role (36–35%), both for bare soil and for WH BC composites, in determining the infiltration rate. Significance of VWC in determining rate of infiltration increases (14–27%) as the BC content increases. This is more likely, as the addition of BC enhanced the water retention capacity.

Temporal dynamics of paddy soil structure as affected by different fertilization strategies investigated with soil shrinkage curve

The paddy soil presents strong structural dynamics due to tillage and frequent Wetting/Drying (WD) cycles. Fertilization practices can affect soil structure and therefore may alter their dynamics. The aim of this study was to investigate the temporal dynamics of paddy soil structure as affected by fertilization strategies using soil shrinkage characteristics. Four long-term fertilization treatments were selected: no fertilization as a control (CK), mineral fertilizer (NPK), mineral fertilizer plus green manure (GM), mineral fertilizer plus green manure and swine manure (GSM). Undisturbed soil cores and bulk soil samples were collected four times during WD cycles. Soil physical properties and shrinkage curves were measured. The results showed that soil bulk density and aggregate stability increased during drying and decreased during wetting, while soil shrinkage capacity was on the contrary. Relative to CK and inorganic fertilization, the application of organic manure decreased soil bulk density and increased aggregate stability, but had no impact on soil shrinkage capacity. Detailed shrinkage analyses manifested the different shrinkage patterns for the different treatments. The GSM treatment had more structural shrinkage than the CK, NPK, and GM treatments because more inter-aggregate pores developed in the GSM treatment. The shrinkage behavior of organic fertilizer treated soils (GSM and GM treatments) was more stable during WD cycles than the NPK and CK treatments. Besides, the CK and NPK treatments had greater slopes at the inflection point (slopeinflection), indicating the soil structure of the GM and GSM treatments was more stable than that of the CK and NPK treatments, which was confirmed by soil aggregate stability data. These results suggest manure should be used to improve soil structure and increase soil stability. We also recommend soil shrinkage curves as a useful tool to study the structural properties, dynamics, as well as the quality of the paddy soil with a high shrinkage capacity.

Analysis of Climate Trends and Leading Modes of Climate Variability for MENA Region

AbstractThe Middle East and North Africa (MENA), primarily the Arabian Peninsula (AP), is a region where the rate of mean surface temperature rise per decade is among the highest globally known during the recent past. Moreover, MENA regional climate is very sensitive to internal and external climate drivers. Therefore, it is of significant practical importance to analyze MENA sensitivity to climate trends as well as leading variability modes such as El Niño Southern Oscillation (ENSO), North Atlantic Oscillation (NAO), and Indian summer monsoon (ISM). Using multiple regression technique on observations and the high‐resolution atmospheric model output, this study investigates the role of climate trends and leading circulation modes such as NAO, ENSO, and ISM in inducing temperature and precipitation variability in MENA region for the period 1979–2008. Our results show substantial regional temperature and precipitation responses of ENSO, NAO, and ISM over MENA. Both the model and the observations indicate that positive phase of NAO and ENSO significantly cools central parts of MENA, in particular, the AP in winter. However, in boreal summer, the warm ENSO phase produces significant warming and drying over the tropical region. The strengthening (weakening) of ISM suggests cooling (warming) and wetting (drying) over MENA rain‐belt region. Moreover, ISM induces a dipole precipitation structure over the tropics caused by Intertropical Convergence Zone shift and associated cloud distribution. High‐resolution atmospheric model slightly underestimates NAO and ENSO winter cooling over the AP; however, overall patterns are well reproduced. The conducted analysis sheds light on the internal mechanisms of MENA climate variability.

Assessment of engineering behaviour of an intensely weathered swelling mudstone under full range of seasonal variation and the relationships among measured parameters

An experimental study was conducted to investigate the physical and mechanical properties of an intensely weathered mudstone from Northeast China after wetting–drying (W–D), freezing–thawing (F–T), and wetting–drying–freezing–thawing (W–D–F–T) cycles. These cyclic climatic processes have significant effects on the volume, microstructure, stress–strain behaviour, shear strength, electrical resistivity, and P-wave velocity of the samples. The variation in electrical resistivity exhibits an inverse correlation with the volume change, and a strong relationship can be observed between the electrical resistivity and porosity. The cohesion decreases with increasing number of cycles, while the internal friction angle slightly increases; these relationships can be caused by the presence of cracks and large voids and by the increase in the aggregate size and density during the drying and freezing processes, respectively. Moreover, the W–D–F–T cycles have a greater influence on the shear strength than do either the W–D or F–T cycles. This phenomenon is similar to that observed in the P-wave velocity, and the relationships between the shear strength parameters and P-wave velocity are also explored. This study provides nondestructive methods of predicting the deformation and shear strength of mudstones in seasonally frozen regions.

Molecular basis for increased 2-acetyl-1-pyrroline contents under alternate wetting and drying (AWD) conditions in fragrant rice

Factors affecting rice aroma biosynthesis have been well documented previously, however the molecular mechanism lies behind the regulations in grain 2-acetyl-1-pyrroline (2AP) biosynthesis under alternate wetting and drying (AWD) remained largely unexplored. Present study investigated the effects of three irrigation regimes i.e., conventional irrigation (CI), alternate wetting and moderate drying (WMD), and alternate wetting and severe drying (WSD) on the yield, quality traits, intermediates, enzyme activities and genes involved in 2-acetyl-1-pyrroline biosynthesis in two fragrant rice cultivars viz, Meixiangzhan2 and Xiangyaxiangzhan. Results revealed that the levels of intermediates such as Δ1-pyrroline-5-carboxylate (P5C) and Δ1-pyrroline, and the activity of enzymes such as proline dehydrogenase (PRODH), Δ1-pyrroline-5-carboxylate synthetase (P5CS), diamine oxidase (DAO), and gene expressions of PRODH, P5CS2 and DAO were comparatively higher under AWD than CI in both aromatic rice cultivars. The levels of gamma-aminobutyric acid (GABA), betaine aldehyde dehydrogenase 2 (BADH2) and BADH2 gene were lower that together led to enhanced 2-AP contents in rice grains. Moreover, WMD irrigation improved yield and yield characters, while WSD irrigation reduced yield and quality traits of rice. Overall, up-regulation of P5C and Δ1-pyrroline and down-regulation of GABA under AWD treatments resulted in enhanced 2AP biosynthesis in both rice cultivars. Evaluation and adoption of AWD (within safe limits) at field level could be an alternative option to conventional flooded rice to get better yield and quality.

Chloride maximum phenomenon near the surface of cement paste induced by moisture evaporation and carbonation

Abundant studies of cyclic wetting–drying of concrete have suggested a “maximum phenomenon” by which chloride concentrations first increase with depth to a local maximum and then decrease at greater depths. This phenomenon may arise primarily because of carbonation, but may also be exacerbated by cyclic capillary suction and moisture evaporation during wetting–drying cycles. This paper investigates the mechanism responsible for the maximum phenomenon under conditions that exclude cyclic capillary suction. The results show that different chloride maxima form near the surface of all specimens under conditions of either accelerated carbonation or carbonation in normal air environment. A large amount of bound chloride is released when carbonation causes decomposition of Friedel’s salt and C–S–H gel, and the decrease in water content significantly increases the chloride concentration in the pore solution near the specimen surface. The resulting chloride concentration gradient drives free chloride diffusion from the surface to the interior, thereby reducing the actual chloride content near the exposed surface. More severe carbonation conditions increase the severity of the maximum phenomenon.

Impact of multiple drying–wetting cycles on shear behaviour of an unsaturated compacted clay

Experimental investigations on the impact of multiple drying–wetting cycles on mechanical behaviour of unsaturated soils, particularly on shear behaviour, are limited. Suction-controlled direct shear tests were carried out to investigate the impact of multiple drying–wetting cycles on shear behaviour of an unsaturated compacted clay. One drying–wetting cycle was applied on a soil specimen by increasing its suction to 400 kPa followed by returning its suction to 1 or 200 kPa at constant vertical stress. The experimental results showed that more significant volume contraction occurred during the first drying–wetting cycle as compared with the subsequent drying–wetting cycles. At higher net normal stress (i.e. 200 kPa), a transition from shear-induced contraction to dilation was found. Nevertheless, such transition from contraction to dilation was not observed for the specimens at lower net normal stress (i.e. 50 kPa). The results also showed that amplitude of drying–wetting cycles and vertical stress influences the shear strength. The shear strength increases slightly after the first drying–wetting cycle at lower net normal stress; at higher net normal stress the effect of the first cycle on the shear strength is contrast.

NMR, MRI and AE Statistical Study of Damage due to a Low Number of Wetting–Drying Cycles in Sandstone from the Three Gorges Reservoir Area

NMR, MRI and AE Statistical Study of Damage due to a Low Number of Wetting–Drying Cycles in Sandstone from the Three Gorges Reservoir Area

Prediction of Expansive Soil Strength Based on Micro-scale Properties

A comprehensive understanding of expansive soil behavior requires elucidation of the surface phenomena of clay particles and soil micro-structure changes. This study focuses on the influences of drying–wetting cycles on cohesion variations, and four micro-scale properties of expansive soils—fissure ratio, void ratio, specific surface area (SSA), and larger pore proportion—are measured to predict cohesion for expansive soil experienced 0–7 drying–wetting cycles. Based on each of these micro-scale properties, single linear regression analyses are used to obtain the cohesion attenuation law with cycle number. Changes in the studied four micro-factors significantly cause a discrepancy of cohesion. The fissure ratio and the SSA are the most two accurate predictor of the attenuation law for the studied soil, which are fitted by a “S” curve. The two “S” curves with lower standard error (< 1.16 kPa) perform well in predicting cohesion attenuation after different drying–wetting cycles in practical engineering. An empirical formula based on the fissure ratio and the SSA, carried out using MATLAB software, is also found to be accurate in predicting the cohesion attenuation of expansive soil. Found from the comparison with similar researches, this empirical formula caring only initial cohesion and cycle number, avoiding measuring micro-scale properties, can be simply used in the expansive soil from a particular area to predict cohesion reduction.

Effects of Wetting–Drying Cycles on Strain–Stress Relationship from Triaxial Test of a Mudstone Mixture

Soils filled in or along bank of a large reservoir may be subjected to wetting–drying cycles induced by cyclic lowering and rising of reservoir water level. The wetting–drying cycles may affect the mechanical behaviors of the soils. This study focused on the effects of wetting–drying cycles on the strain–stress relationship from triaxial test of a mudstone mixture. Several consolidated drained triaxial tests with wetting–drying cycles were carried out. Experimental data indicates that the wetting–drying cycles may induce an increment of axial strain, Δe, and a decrement of deviator stress, Δ(σ1 − σ3). With increment of the number of cycles, N, the values of Δe and Δ(σ1 − σ3) are increasing along logarithmic curves. Both change rates of Δe and Δ(σ1 − σ3) are sharply dropping with increment of N value. Thus, the effects of wetting–drying cycles on the strain–stress relationship of test material are mainly concentrated on the period of first several cycles. Based on experimental data, several fitting equations, which may estimate the values of Δe, Δ(σ1 − σ3), change rates of Δe and Δ(σ1 − σ3), with increment of N value, were suggested.

Comparison on physiological adaptation and phosphorus use efficiency of upland rice and lowland rice under alternate wetting and drying irrigation

As one of the most widely promoted water-saving irrigation strategies for rice, alternate wetting and drying irrigation (AWD) can not only save water but also increase mineral nutrient use efficiency. In this study, we compared the growth conditions of four rice varieties (two lowland and two upland varieties) under three irrigation regimes: continuously flooded (CF), alternate wetting and moderate soil drying (AWD15) and alternate wetting and severe soil drying (AWD30). AWD15 and AWD30 enabled the plants to receive fewer irrigation events and less irrigation water than CF, thereby saving both water resources and labor. AWD15 reduced redundant vegetative growth, promoted root growth, and increased the root-shoot ratio and harvest index. AWD15 increased the grain yield, water use efficiency (WUE) and phosphorus use efficiency (PUE) of upland rice and maintained the grain yield while increasing the WUE and PUE of lowland rice. More developed root systems under AWD helped upland rice to maintain a higher water status than lowland rice when plants were subjected to soil drying, which resulted in superior performance in grain yield in upland rice. AWD30 could not reconcile the demands of higher yield and the desire to reduce irrigation water use because it decreased grain yield. The results indicate that AWD15 irrigation of rice can not only increase rice yield and WUE but also enhance PUE, which can potentially reduce the use of phosphorus fertilizers. The results provide theoretical and technical support for improving rice cultivation.

Morphological Approach to Quantifying Soil Cracks: Application to Dynamic Crack Patterns during Wetting‐Drying Cycles

Core Ideas We propose a methodology for soil crack recognition and quantification. Crack skeleton, outline and nodes are produced using morphological algorithms. A novel method for separating cracks is proposed based on SKIZ, distance transform, and watershed segmentation. The approach is assessed on dynamic crack patterns derived from three wetting‐drying cycles. Crack degree, velocity, similarity and network topology within wet‐dry cycles are analyzed. Water flow and solute transport through shrink‐swell soils with desiccation cracks are dominated by the crack distribution and variable hydraulic properties. The quantification of cracks is therefore inevitable for predicting moisture movement in cracked soils. This study presents a morphological approach to crack recognition and quantification based on digital image processing and morphological algorithms. The methodology comprises three sections: image segmentation, morphological processing and parameter calculation. A crack image is first segmented and then subjected to morphological operations including skeletonization, node identification and crack outline extraction. Based on the resulting binary crack image, skeleton and nodes of crack network, we propose a novel approach to crack separation by employing the concept of skeleton by zones of influence (SKIZ) and algorithms including distance transform and watershed segmentation. Calculations of crack parameters are presented and we apply this methodology to quantify the characteristics of dynamic crack patterns derived from wetting‐drying (W‐D) cycles. Crack degree, propagation velocity of cracks, similarity between crack patterns and network topology are exemplified to delineate the dynamic crack patterns. We find that the cracking degree present hysteresis between W‐D processes, similarly to soil shrink‐swell characteristics and water retention curves. The crack skeleton simultaneously, non‐hierarchically and rapidly propagated in successive drying cycles compared to the initial drying process. The similarity between two crack patterns with similar moisture contents derived from W‐D cycles is positively correlated with the drying intensity, and the evolution of the similarity gradually decelerates with decreasing water content. The crack patterns at full desiccation across W‐D cycles exhibit a marked similarity, with a maximum similarity measure of approximately 0.8. Overall, this approach could achieve efficient recognition and quantification of crack patterns and has great potential in the 3‐D quantification of cracks or related structures.

Future Precipitation Projections over Central and Southern Africa and the Adjacent Indian Ocean: What Causes the Changes and the Uncertainty?

Future projections of precipitation at regional scales are vital to inform climate change adaptation activities. Therefore, is it important to quantify projected changes and associated uncertainty, and understand model processes responsible. This paper addresses these challenges for southern Africa and the adjacent Indian Ocean focusing on the local wet season. Precipitation projections for the end of the twenty-first century indicate a pronounced dipole pattern in the CMIP5 multimodel mean. The dipole indicates future wetting (drying) to the north (south) of the climatological axis of maximum rainfall, implying a northward shift of the ITCZ and south Indian Ocean convergence zone that is not consistent with a simple “wet get wetter” pattern. This pattern is most pronounced in early austral summer, suggesting a later and shorter wet season over much of southern Africa. Using a decomposition method we determine physical mechanisms underlying this dipole pattern of projected change, and the associated intermodel uncertainty. The projected dipole pattern is largely associated with the dynamical component of change indicative of shifts in the location of convection. Over the Indian Ocean, this apparent northward shift in the ITCZ may reflect the response to changes in the north–south SST gradient over the Indian Ocean, consistent with a “warmest get wetter” mechanism. Over land subtropical drying is relatively robust, particularly in the early wet season. This has contributions from dynamical shifts in the location of convection, which may be related to regional SST structures in the southern Indian Ocean, and the thermodynamic decline in relative humidity. Implications for understanding and potentially constraining uncertainty in projections are discussed.

The effect of alternate wetting and severe drying irrigation on grain yield and water use efficiency of Indica‐japonica hybrid rice (Oryza sativa L.)

AbstractIdentification of a rice cultivar with high yield potential has been heavily sought by researchers in China, and pursuant to this goal, several indica‐japonica hybrid rice (IJHR) cultivars have been studied for over a decade. However, in addition to high yield, it is important that the cultivar also exhibit good water use efficiency (WUE). This study compared the yield performance and WUE of the IJHR cultivars under alternate wetting and severe drying (AWSD) irrigation regimen to the japonica inbred rice (JIR) cultivars. Field experiments were conducted on two representative IJHR cultivars (Chunyou927 and Yongyou538) and two representative JIR cultivars (Xiushui09 and Zhejing99) in 2015 and 2016 with two different irrigation methods: continuous flooding (CF) and AWSD. Irrigation water was 275–349 mm in the AWSD irrigation regimen, which was 49.8%–56.2% of that (552–620 mm) applied to the CF irrigation regimen. Compared to CF, the AWSD irrigation method significantly decreased grain yield in both IJHR and JIR cultivars, with a more significant reduction in JIR cultivars, and WUE was improved in both the IJHR and JIR cultivars, especially in the IJHR cultivars. Compared to the JIR cultivars, the IJHR cultivars were found to have improved agronomic and physiological performances under the AWSD irrigation regimen, such as a larger sink size, higher percentage of productive tillers, higher matter production ability during reproductive and ripening periods, larger root biomass, deeper root distribution and greater nonstructural carbohydrate (NSC) accumulation in the stem at heading, larger NSC remobilization from the stem, and higher root oxidation activity and leaf photosynthetic rates during ripening period. Improved agronomic and physiological traits contributed to an increase in WUE with less yield loss for IJHR cultivars under the AWSD irrigation regimen.