Estimates Of Water Use Research Articles

Estimation of Consumptive Water Use for Watermelon in Auchi, Nigeria

Estimation of Consumptive Water Use for Watermelon in Auchi, Nigeria

Intercomparison of citrus evapotranspiration among eddy covariance, OpenET ensemble models, and the Water and Energy Balance Model (BAITSSS)

Remote sensing-based surface energy balance algorithms have been used to estimate water use of various crops. However, citrus evapotranspiration (ET) estimation is challenging mainly due to evergreen leaves and a clumped canopy structure. In this study, we evaluated the performance of two methods for calculating ET: the ensemble of OpenET models, which are mostly satellite thermal-based models, and the BAITSSS water and energy balance model. Calculated ET was compared with (i.) eddy covariance (EC) ET measurements and (ii.) water received (irrigation plus precipitation) data for two citrus orchards in San Joaquin Valley, California. Polaris-based soil hydraulic properties and measured volumetric water content were used for BAITSSS parameterization and initialization, respectively. Sentinel-2 based NDVI was used for BAITSSS simulation. Results showed that annual ET based on the OpenET ensemble model (1169 mm) was on average 30 % larger (r2 ∼ 0.71, RMSE ∼ 1.16 mm) than both EC ET (908 mm) and water received (886 mm). The disparity mostly occurred in spring. BAITSSS, on the other hand, showed mixed results compared to observations (r2 ∼ 0.77, RMSE ∼ 0.94 mm). Both measured from EC and modeled ET from BAITSSS and ensemble OpenET values were below grass reference ET (ETo) for the majority of the simulation period. Soil moisture and water received data indicated the orchards may have been deficit irrigated. Overall, this study highlights the challenges of ET modeling in citrus orchards and the need for improved estimation of ET for this specialty crop.

Research on a zero water consumption operation model and feasibility for office buildings

ABSTRACT According to Taiwan's government policy on net zero emissions by 2050, building designs are moving toward zero energy and zero water consumption to achieve these challenge goals. Among these goals, establishing an independent water cycle within building systems is a primary objective. The present study examined office buildings as the research subject due to their crucial water usage characteristics, which can serve as a reference for other building types. We developed a water-use estimation model by conducting a literature review and data collection from existing green office building cases in Taiwan. The methods involved calculating the median annual water consumption per unit building area and discussing the current water-saving design status and water-saving rate. The findings indicate a median water-saving rate of 53%, which is far short of the goal of achieving a zero water building. This finding is primarily attributed to the infrequent use of water compensation in building designs. The feasibility of a zero water building is validated and determines its crucial operation. Consequently, design engineers can employ this methodology to compute water conservation rates for their designs, aiming for the construction of a zero water consumption building.

Sensitivity of water reallocation performance assessments to water use data

The lack of detailed and reliable data on the estimates of water use has been a key limitation in informing sustainable, equitable and efficient water reallocations in the agricultural sector. Conventional water use data have been commonly obtained from surveys or agronomic models, which have limitations on accurately reflecting the actual water use. This paper integrates cutting-edge satellite-based water use data with an ensemble of four Calibrated Mathematical Programming Models (CMPM) (one Positive Multi-Attribute Utility Programming model, one Weighted Goal Programming model, and two Positive Mathematical Programming models) to assess and compare the performance of water reallocations under satellite-based versus conventional water use estimates. We apply these methods to the water-stressed Mancha Oriental Aquifer (MOA) in central Spain, where we simulate the impacts of a hypothetical temporary water reacquisition policy in 2017, the last dry year in record. We find that water use estimates obtained with conventional approaches (which range between 4916 m3/ha and 4510 m3/ha, on average) are 13–24 % lower than satellite-based estimates (5577 m3/ha on average) during the dry year. Moreover, the water reacquisition simulation using the CMPM ensemble shows that the reserve prices (25–66 % higher) and buyback costs (26–67 % higher) derived from conventional water use data approaches are consistently and significantly higher than those derived from satellite-based water use estimates for all the elements of the ensemble, suggesting that a policy informed with satellite-based data could significantly reduce the costs of the reallocation.

Estimating crop coefficients and water use of a full-bearing mango orchard in north-eastern South Africa using the fraction of vegetation cover and a dual source evapotranspiration model

In semi-arid countries like South Africa, commercially produced mango (Mangifera Indica L.) are grown entirely under irrigation. However, there is little accurate quantitative information on the water use of mango orchards, and few accurate water use models currently exist. In this study, we evaluated the performance of the FAO 56 method of estimating crop evapotranspiration (ETc) and a dual source water use model against measurements of actual consumptive water use of a commercial mango orchard. The FAO approach calculates ETc as the product of a crop coefficient (Kc) and the reference evapotranspiration (ETo). We derived Kc for well-watered orchards from readily available data including the fraction of vegetation cover, average tree height, and a stomatal control coefficient. The dual-source model calculated orchard evapotranspiration as the sum of tree transpiration and orchard floor evaporation derived from the modified Shuttleworth and Wallace model. Actual evapotranspiration was measured using an open path eddy covariance system, while tree transpiration was measured using the heat ratio method of monitoring sap flow. Data were collected in a mature ‘Tommy Atkins’ mango orchard grown with micro-sprinkler irrigation in north-eastern South Africa. Results show that the reference evapotranspiration explained most of the variation in orchard transpiration (R2 ∼ 0.78) compared to the solar radiation (R2 ∼ 0.66) and the vapour pressure deficit of the air (R2 ∼ 0.66). Compared with field measured water use data, the FAO method gave relatively accurate estimates of transpiration (R2 = 0.74, NRMSE = ±18.00 %, NMAE = ±15.00 %, NSE = 0.70) and evapotranspiration (R2 = 0.58, NRMSE = ±19.00 %, NMAE = ±16.00 %, NSE = 0.55). NSE is the Nash-Sutcliffe Efficiency. The dual-source model yielded slightly less accurate estimates of transpiration (R2 = 0.61, NRMSE = ±22.00 %, NMAE = ±20.00 %, NSE = 0.39) and evapotranspiration (R2 = 0.52, NRMSE = ±23.00 %, NMAE = ±25.00 %, NSE = 0.51). The basal crop coefficient (Kcb) showed small seasonal fluctuations, varying between 0.40 and 0.60 throughout the year. In contrast, Kc showed clear seasonality varying between 0.59–0.64 at flowering and fruit set and rising to 0.81–0.90 during the fruit growing phase. Estimates of the annual total transpiration (686 mm) from the FAO method were within 5 % of the actual measured values (677 mm) while the dual source model estimated 612 mm of transpiration, which was almost 10 % lower than the measured values. The results highlight that even though the FAO method requires fewer input parameters, it is potentially more accurate in estimating water use in mango orchards than the dual-source model.

Farmer response to policy induced water reductions: Evidence from the Colorado River

Surface water supplies are becoming increasingly strained, pushing policy makers to find solutions to facilitate reductions in water use though there is limited evidence on how farmers respond to policy induced variation in surface water supplies. This paper uses a difference-in-differences framework to compare the response of farmers to a bundle of policies reducing deliveries from the Colorado River by 35%. I find that on average, farmers reduce the amount of land planted but plant more water intensive crops leading to a minimal reduction in total estimated water use compared to the counterfactual. Additionally, there is strong suggestive evidence that farmers are using groundwater to offset a significant amount of the surface water loss. These findings have important consequences for understanding the relative trade-offs policy makers face when implementing policies that protect surface water sources.

HESS Opinions: The unsustainable use of groundwater conceals a “Day Zero”

Abstract. Water scarcity is a pressing global issue driven by increasing water demands and changing climate conditions. Based on novel estimates of water availability and water use in Chile, we examine the challenges and risks associated with groundwater (GW) withdrawals in the country's central-north region (27–35° S), where extreme water stress conditions prevail. As total water use within a basin approaches the renewable freshwater resources, the dependence on GW reserves intensifies in unsustainable ways. This overuse has consequences that extend beyond mere resource depletion, manifesting into environmental degradation, societal conflict, and economic costs. We argue that the “Day Zero” scenario, often concealed by the uncertain attributes of GW resources, calls for a reconsideration of water allocation rules and a broader recognition of the long-term implications of unsustainable GW use. Our results offer insights for regions worldwide facing similar water scarcity challenges and emphasize the importance of proactive and sustainable water management strategies.

Socioeconomic impact of agricultural water reallocation policies in the Upper Litani Basin (Lebanon): a remote sensing and microeconomic ensemble forecasting approach

The integration of remote sensing and socio-economic data is crucial for policy making in regions suffering from water scarcity and climate change. We present a framework that combines remotely sensed estimates of biomass and water use from FAO’s Water Productivity Open-access portal (WaPOR) (V2) with an ensemble of calibrated mathematical programming models to assess the impact of water reallocations on rain-fed and irrigated land use and production in water-stressed basins. We evaluated our model in the Upper Litani Basin of Lebanon using two water reallocation policies: (i) quotas that progressively reduces water allocation for irrigation up to 100%, at 1% intervals and (ii) a pricing policy that increases the agricultural water price up to 0.25 USD/m3, at 0.0025 USD/m3 intervals. Our results reveal that 1) the impacts of water availability reductions due to quotas on profit and employment are less-than-proportional when water allocation is reduced by <50%, but abruptly increase when water allocation is reduced by >50%; 2) irrigators responses to prices are inelastic until a price increase of 0.03 USD/m3, become significantly more elastic afterwards, and again become inelastic above a price increase of 0.06 USD/m3; 3) higher water prices progressively reduce profit and labor, significantly reduce water use over the elastic interval (where irrigators cultivating low value-added crops shift to rainfed agriculture), and increase tariff revenue during the inelastic interval (where irrigators largely stick to their crop portfolios and pay the higher water prices). Our results reveal nontrivial uncertainties and tipping points, thus highlighting the value of combining reliable water use data with multi-model and multi-scenario ensembles in informing robust policies.

Patterns of water use by the Australian native Melaleuca styphelioides in urban environments and comparison of transpiration prediction by three different micrometeorological models

Key messageThe high-quality sap flow dataset of Melaleuca styphelioides could assists local councils in assessing tree water use and aids in the development of an urban tree sustainable planting management planTrees have a vital part to play in urban ecosystems, offering ecological, economic, and social advantages in addition to beautifying our suburbs. Knowledge of tree water use in urban environments is crucial for facilitating urban greening when there is a perception that growing trees on the street verge on expansive soils poses a risk to pavement and buildings. Information on long-term water use by individual trees in an urban environment is essential for local councils in developing urban tree management plans for sustainable planning of trees; however, this information is scarce. Micrometeorological models have commonly been used to estimate the canopy transpiration of plants in the absence of sap flow data. However, the reliability and accuracy of these models have rarely been assessed using sap flow measurements at the field site. This study aimed to provide the water use data of four individual Australian native Melaleuca styphelioides Sm. using sap flow instruments over 25 months. Tree transpiration, estimated based on three commonly used micrometeorological models using weather parameters and tree characteristics, was assessed and compared with sap flow measurements by employing the linear regression statistical analysis. The results revealed that the modified Penman–Monteith (PM) model demonstrated the highest level of accuracy among the evaluated models, consistently yielding lower errors and providing more reliable estimates of tree water use. This suggests that this model may be more appropriate for predicting plant water use in situations where sap flow data are unavailable.

Determinants of the accuracy of using carbon isotopes in estimating water use efficiency of selected cereal and legume crops: A global perspective

AbstractField assessments of crop water use efficiency (WUE) are resource‐consuming since they require simultaneous assessment of the total amount of water assimilated by crops for biomass and/or grain production. Alternative methods exist, such as estimating the carbon isotopic ratio (13C/12C) of the crop's leaf, aboveground biomass, or grain samples. There is limited information on the determinants of the accuracy of carbon isotopes in estimating water use efficiency between crop types and environments. Therefore, this study aimed to evaluate the extent to which the estimation of the 13C/12C ratio in crop parts constitutes an accurate proxy of WUE, globally. Data on observed WUE (WUEobs) were collated involving 518 experiments conducted worldwide on major cereals and legumes and compared with WUE estimates (WUEest) from carbon isotopes. The mean WUEobs among all experiments was 3.4 g L−1 and the mean absolute error (MAE) was 0.5 g L−1 or 14.7% of WUEobs, corresponding to accurate predictions at p &lt; 0.05. However, the percentage mean absolute error of observed water use efficiency (%MAE) estimated from grains was 3.6 ± 11.5%, which was lower than the %MAE from aboveground biomass collected at harvest (3 ± 22.8%). In addition, the %MAE increased from 1.1 ± 5.1% for soybean, 1.6 ± 7.2% for maize, 1.2 ± 8.6% for rice, 1.8 ± 12.1% for groundnut, 2.1 ± 14.3% for cowpea, 2.3 ± 16.2% for bush bean, 1.8 ± 19.9% for wheat, 2.2 ± 21.4% for barley to 6.3 ± 39.3% for oat, with only the latter corresponding to significant errors. WUEest were, in all cases, unbiased but slightly overestimated from 0.8% (maize) to 15.4% (oat). The accuracy in estimating WUE significantly decreased with the increase in soil clay content, with sand, showing a positive correlation of 0.3 with %MAE, but negatively correlated with the silt content (r = −0.4). Furthermore, a multivariate analysis pointed out a tendency for prediction errors and bias to increase with the decrease in WUEobs and air temperature. Using carbon isotopes for estimating crop WUE thus appeared reliable for all crops and world environments, provided grain samples are considered. The technique tended to perform better under high WUE conditions, such as those generally found in maize and soybean cropping systems. The identified factors that affect the accuracy of using carbon isotopes in measuring WUE provide valuable insights for water resource management and sustainable crop production. These findings contribute to the ongoing discourse on water conservation strategies in agriculture, offering a basis for decision‐making in crop improvement programs. Implementing the recommended practices from this study can potentially improve yield gains and promote resilient and sustainable agricultural systems in the changing environmental circumstances. Further research should investigate the mechanisms that cause low accuracy of the isotopic technique using aboveground biomass and under arid and cool environments.

Predicting and understanding residential water use with interpretable machine learning

Predicting residential water use is critical to efficiently manage urban water resource systems. Simultaneously, understanding the factors driving residential water use is required to plan for future urban change and achieve effective water resource management. Current approaches examining residential water use identify the drivers of household water use through parametric or non-parametric statistical approaches. Parametric approaches have high predictive errors and lack the ability to accurately capture interactions between features but allow for easy interpretation. Non-parametric approaches have lower predictive errors and can capture non-linear feature interactions but do not allow for easy interpretation. We use non-parametric statistical models of household water use and recent advances in interpretable machine learning to understand the drivers of residential water use. Specifically, we use post-hoc interpretability methods to examine how drivers of water use interact, focusing on environmental, demographic, physical housing, and utility policy factors. We find all four categories of factors are important for estimating water use with environmental and utility policy factors playing the largest role. Additionally, we identify non-linear interactions between many variables within and across these classes. We show this approach provides both high predictive accuracy and identification of complex water use factors, offering important insight for urban water management.

High-resolution estimation of industrial water use in Beijing-Tianjin-Hebei based on multi-source data

Understanding changes in industrial water use at finer spatial scales is critical for regional water allocation and sustainability. This study employs a top-down method based on multi-source data to estimate the industrial water use at 1 km × 1 km resolution in the Beijing-Tianjin-Hebei (BTH) region during 2000–2019. Statistical data from municipalities and prefectures are used to assess the accuracy of simulated industrial water use. During the validation period, all accuracy validation indices (R, NSE, |RE|, RMSE) have achieved good results, indicating that the method is credible. In addition, industrial water use at the county level in BTH has a strong spatial correlation with 99% confidence. Spatiotemporal change pattern mainly depends on the industrial scale and technical level of prefecture-level cities, and the economic environment will also contribute to changes in the annual industrial water use in BTH. The method provides a reference for high-resolution estimation of industrial water use and can also be applied to regional water management and allocation.

Data‐driven modeling to enhance municipal water demand estimates in response to dynamic climate conditions

AbstractAltered precipitation and temperature patterns from a changing climate will affect supply, demand, and overall municipal water system operations throughout the arid western U.S. While supply forecasts leverage hydrological models to connect climate influences with surface water availability, demand forecasts typically estimate water use independent of climate and other externalities. Stemming from an increased focus on seasonal water demand management, we use the Salt Lake City, Utah municipal water system as a test bed to assess model accuracy versus complexity trade‐offs between simple climate‐independent econometric‐based models and complex climate‐sensitive data‐driven models to average to extreme wet and dry climate conditions—representative of a new climate normal. The climate‐independent model displayed low performance during extreme dry conditions with predictions exceeding 90% and 40% of the observed monthly and seasonal volumetric demands, respectively, which we attribute to insufficient model complexity. The climate‐sensitive models displayed greater accuracy in all conditions, with an ordinary least squares model demonstrating a measurable reduction in prediction bias (3.4% vs. −27.3%) and RMSE (74.0 lpcd vs. 294 lpcd) compared to the climate‐independent model. The climate‐sensitive workflow increased model accuracy and characterized climate‐demand interactions, demonstrating a novel tool to enhance water system management.

Assessment of the factors shaping the public’s perception of physical and virtual water: A case study of Korean households

Water demand management is a crucial approach for ensuring sustainable water supply. To ensure an effective water demand management, it is essential to have a good understanding of public perceptions of water use. In this study, we examined the perceptions of water use and virtual water of Daegu inhabitants in South Korea, with a focus on understanding their sociodemographic characteristics, water-saving behaviors, environmental attitudes, and accuracy in estimating water use and virtual water content. The results indicated that the majority of respondents were aware of the need for water conservation but exhibited only moderate engagement in water-saving behaviors. They consistently underestimated their water use across various activities (portable drinking water, shower, toilet flush, laundry and car wash), indicating a lack of understanding regarding the magnitude of water consumption. Similarly, respondents had limited awareness of the virtual water content in different products, with inaccurate perceptions of water-intensive products. Sociodemographic factors such as gender, education level, annual income, and family size significantly influenced perceptions of water use, while environmental attitudes played a significant role in the perceptions of both water use and virtual water content. The study highlights the need for educational initiatives to enhance public awareness and understanding of water use and virtual water, particularly in addressing misconceptions and promoting sustainable water management practices. While the findings are specific to Daegu city, they provide insights that can inform water management strategies in other cities globally.

The slope of assimilation rate against stomatal conductance should not be used as a measure of water use efficiency or stomatal control over assimilation

Quantifying water use efficiency, and the impact of stomata on CO2 uptake are pivotal in physiology and efforts to improve crop yields. Although tempting, relying on regression slopes from assimilation-stomatal conductance plots to estimate water use efficiency or stomatal control over assimilation is erroneous. Through numerical simulations, I substantiate this assertion. I propose the term ‘instantaneous transpiration efficiency’ for the assimilation-to-transpiration ratio to avoid confusion with ‘intrinsic water use efficiency’ which refers to the assimilation-to-stomatal conductance ratio, and recommend to compute both metrics for each gas exchange data point.

Using a crop water stress index to determine water use efficiency in a raspberry crop in the Mediterranean Central Chile

AbstractWater availability is projected to decrease in Mediterranean Central Chile, necessitating sustainable production strategies based on improved irrigation management. This study focuses on estimating water use efficiency (WUE) in raspberry crops at two validation sites using remote sensing and soil irrigation data. By employing the crop water stress index (CWSI), we demonstrate the potential of this tool in enhancing irrigation management and establishing sustainable production practices. The results demonstrate the successful estimation of actual evapotranspiration (ETa) using the Operational Simplified Surface Energy Balance (SSEBop) model (coefficient of determination [R2] = 0.92; root mean square error [RMSE] = 0.97 mm day−1), while the CWSI indicated high stress levels after 5 days of irrigation. Moreover, validation at two sites reveals significant differences in applied irrigation, with sites A and B receiving 17,097 and 3760 m3 ha−1, respectively, while the average water demand is close to 5300 m3 ha−1. These variations result in discrepancies in WUE, with values of 0.79 and 3.64 kg m−3. By integrating remote sensing indices and soil data, this study proposes that maintaining an 85% ETa rate during noncritical periods can enhance WUE. This work demonstrates the potential use of a water stress index to monitor crops in the Chilean central zone for efficient water resource use under future scarcity scenarios.

Estimation of Irrigation Water Use by Using Irrigation Signals from SMAP Soil Moisture Data

Accurate irrigation water-use data are essential to agricultural water resources management and optimal allocation. The obscuration presented by ground cover in farmland and the subjectivity of irrigation-related decision-making processes mean that effectively identifying regional irrigation water use remains a critical problem to be solved. In view of the advantages of satellite microwave remote sensing in monitoring soil moisture, previous studies have proposed a method for estimating irrigation water use using the satellite microwave remote sensing of soil moisture. However, the method is affected by false irrigation signals from soil moisture increases caused by non-irrigation factors, causing irrigation water use to be overestimated. Therefore, the purpose of this study is to improve the estimation of irrigation water use in drylands by using irrigation signals from SMAP soil moisture data. In this paper, the irrigation water use in Henan Province is estimated by using the irrigation signals from SMAP (soil moisture active and passive) soil moisture data. Firstly, a method for recognizing irrigation signals in soil moisture data obtained by microwave satellite remote sensing was used. Then, an estimation model of the amount of irrigation water (SM2Rainfall model) was built on each data pixel of the satellite microwave remote sensing of soil moisture. Finally, the amount of irrigation water utilized in Henan Province was estimated by combining the irrigation signals and irrigation water-use estimation model, and the results were evaluated. According to the findings, this study improved the estimation accuracy of irrigation water use by using the irrigation signals in Henan Province. The result of this study is of great importance to accurately obtain irrigation water use in the region.

Farm-level Hydroeconomic Analysis of Alternative Water Tariff Charges Using a Hybrid Solution Method

This paper's main objective is to develop a farm-level water programming model to realistically model extensive margin and intensive margin responses resulting from deficit irrigation to the implementation of volumetric water charges. The highly complex programming model that uses the FAO56 water budget calculations to simulate crop water use while using relative evapotranspiration to estimate crop yield is solved using a hybrid procedure. The hybrid solution procedure uses a genetic algorithm to simplify the optimization model by fixing the irrigation schedule of each crop and then solving for the optimal water allocation amongst crops subject to water constraints. The area-based charges results showed that when irrigation application efficiency is low, irrigators could apply more water per hectare to sustain high crop yields without being held accountable if water quotas are exceeded. In contrast, irrigators with higher application efficiency could use less water than the area-based estimated water use. The results also showed that volumetric water charges cause both intensive margin and extensive margin responses. The conclusion of whether a volumetric-based water charging system will be better than area-based water charges is not straightforward because of differentiated impacts on profitability and hydrology. While irrigators will use irrigation water more efficiently and adopt more efficient irrigation technologies, their changed behavior could impact the hydrology of the water system through reduced return flows.

A LONG-TERM ESTIMATION AND MODELING OF DOMESTIC WATER RESOURCES IN THE YARMOUK RIVER BASIN-JORDAN

This paper presents an assessment of the supply and demand of domestic water resources in the Yarmouk River Basin-Jordan over a twenty-year period and a long-term estimate of domestic water use for the coming years through 2030. The basin was selected because of water-related problems ranging from management to water scarcity and overpopulation. These problems have increased pressure on the domestic water supply, thus the population’s demand for water far exceeds the water supply from internal wells, necessitating management actions to bridge the gap between domestic supply and demand. The method includes identifying the governorates, wells, cities, villages, and computing the population in the basin governorates. Domestic water demand was assessed on a per capita water basis in 1997 and 2017. An Autoregressive Integrated Moving Average (ARIMA) model was used to estimate usage behavior. The results showed an increase in the basin population from 0.64 to 1.53 million, more than doubling. Comparing the population demand with the internal water supply showed significant changes, as the increase in water use was remarkably high despite the decline in per capita water. ARIMA estimates a 2% increase in domestic use annually and 15% through 2030, challenging the future of water supplies. Water management actions will address this challenge, such as the inter-basins located outside the Yarmouk Basin, thus resolving supply shortage issues. These findings are important as a baseline for future studies, and can assist stakeholders in taking actions such as reviewing groundwater data, detecting illegal practices, water harvesting, and assessing non-revenue water.

Water Use Efficiency in Young Citrus Trees on Metalized UV Reflective Mulch Compared to Bare Ground

A precise estimation of plant water use is crucial for efficient irrigation management and understanding of plant–water interactions. Metalized-polyethylene mulch as a ground cover, combined with irrigation management, can improve water and fertilizer use, efficiency growth, and yield of young citrus trees, compared to bare ground. Thus, a study was undertaken to (i) compare daily water use, using the stem heat balance (SHB) method on ≤4-year-old citrus trees using three irrigation methods, and (ii) to determine soil moisture content, as well as total available soil water (TASW) in the irrigated zone. Three irrigation methods, regulated deficit irrigation (RDI), conventional drip irrigation (CD), and microsprinkler irrigation (MS), were applied on two sandy soils in central and southwest Florida with treatments further split between trees grown on 2.4 m mulched beds (M) and bare ground (NM) to form a factorial design. Measurements included sap flow, canopy size, leaf area index (LAI) and soil moisture. The result of this study shows greater values for the trunk cross-sectional area, canopy volume and LAI for both mulch treatments, in comparison to bare ground treatments. The sap flow data suggest that RDI resulted in higher water use than both CD and MS. The hourly sap flow was 120, 99 and 163% greater in M-RDI than M-CD, NM-CD and NM-MS, respectively. Mulched ground cover showed a higher soil moisture average at all soil layers (8-, 15- and 45-cm depth). For instance, the mulched ground cover showed higher soil moisture (37%) at a 15 cm depth at the Entisol site, followed by 30% at a 45 cm depth and 25.3% at depth 45 cm for the Spodosol site. The TASW values varied between 100 to 136% for both mulch and bare ground treatments. The irrigation systems used showed water contents close to field capacity, indicating that water was not limiting despite the different irrigation schedules. The high-water uptake is ascribed to frequent irrigation applications and pulses, and improved water distribution in the irrigated zone as a result of the mulch. These findings demonstrate the potential of metalized-polyethylene mulch and regulated drip irrigation to enhance water use efficiency.