Irrigation and Drainage最新文献

Addressing limitations in fine sediment particle removal within gravity sedimentation tanks, this study investigates three inclined tube configurations: straight with an angle of 60° (ITS), V-shaped with angles of 60° and 60° (ITV1) and V-shaped with angles of 60° and 45° (ITV2), alongside a control group without inclined tubes. Three sediment sizes (0–150, 0–200 and 0–250 μm) and two flow rates (36 and 72 m³·h⁻¹) were tested. Numerical simulations were conducted to examine the mechanisms behind sediment removal. Compared with the control, the use of inclined tubes significantly reduced the sediment concentration by 34%–64% and the median particle size by 36%–65%. V-shaped tubes outperformed straight tubes, especially the ITV2. This improvement was attributed to flow redistribution, expanding the sedimentation area, while the sedimentation tubes promote better flow uniformity than straight tubes through secondary flow redistribution. Furthermore, the inclined tubes showed notable differences in the removal of large, medium and small particles, with the most significant reduction in medium-sized particles, achieving a 36%–65% decrease compared with that of the control. This study clarifies the effects of different inclined tube designs on fine sediment removal, providing insights for optimizing sedimentation tanks in agricultural irrigation systems.

With new trends for intensification, questions on the sustainability of irrigated agriculture and efficient water demand management need to be investigated under water shortage. A field experiment was conducted to improve water management of peach orchards in Northern Tunisia. An early peach cultivar grafted on GF677 and Cadaman was subjected to mild (DI₁) and severe (DI₂) deficit irrigation in a public irrigation network with poor reliability of supply. Tree and soil water status, yield, fruit quality and water productivity (W_p) were investigated. Tree water status under contrasting water supply was affected by rootstock. Lower predawn (Ψ_PD) and stem (Ψ_stem) water potentials were observed on less vigorous Cadaman. Ψ_PD and Ψ_stem were linearly correlated with each other and with soil water content and water supply index K_s (as ratio [Irrigation + Precipitation]/ET_o). Fruit yield and W_p were significantly reduced with DI₂ for both rootstocks. Lower yields were also obtained in the warmest year. In conclusion, Ψ_stem and K_s could be considered as valuable tools for deficit irrigation scheduling with threshold values established for DI₁ and DI₂ with adjustment according to rootstock type. Low-chill cultivar with vigorous rootstock and mild deficit seemed to be the best solution in warm areas under water scarcity.

With new trends for intensification, questions on the sustainability of irrigated agriculture and efficient water demand management need to be investigated under water shortage. A field experiment was conducted to improve water management of peach orchards in Northern Tunisia. An early peach cultivar grafted on GF677 and Cadaman was subjected to mild (DI₁) and severe (DI₂) deficit irrigation in a public irrigation network with poor reliability of supply. Tree and soil water status, yield, fruit quality and water productivity (W_p) were investigated. Tree water status under contrasting water supply was affected by rootstock. Lower predawn (Ψ_PD) and stem (Ψ_stem) water potentials were observed on less vigorous Cadaman. Ψ_PD and Ψ_stem were linearly correlated with each other and with soil water content and water supply index K_s (as ratio [Irrigation + Precipitation]/ET_o). Fruit yield and W_p were significantly reduced with DI₂ for both rootstocks. Lower yields were also obtained in the warmest year. In conclusion, Ψ_stem and K_s could be considered as valuable tools for deficit irrigation scheduling with threshold values established for DI₁ and DI₂ with adjustment according to rootstock type. Low-chill cultivar with vigorous rootstock and mild deficit seemed to be the best solution in warm areas under water scarcity.

Assessing the spatiotemporal dynamics of crop production water footprint (WF) at the regional scale is critical for optimizing agricultural water resource management. However, studies quantifying WF in the Hetao Irrigation District (HID) using distributed agro-hydrological models remain limited, and integration of WF quantification with time-series models for short-term forecasting and WF-driven planting optimization is still lacking. In this study, a calibrated SWAP-WOFOST model was employed to quantify the total water footprint (WF_total), blue water footprint (WF_blue) and green water footprint (WF_green) of spring wheat, spring maize and sunflower in the HID during 2000–2017. Temporal trends were analysed using time-series techniques, and the evolution of WF_total from 2018 to 2027 was projected using the ARIMA model. Spatial WF patterns were further mapped to optimize crop allocation. The results revealed that WF_blue for all crops exhibited a continuous upward trend during 2000–2017, which consistently exceeded WF_green that showed a declining trend. Projections indicated a sustained increase in WF_total from 2018 to 2027, with spring wheat demonstrating the highest growth rate. Following crop allocation optimization, WF_total for all crops decreased significantly, accompanied by enhanced water use efficiency. This study provides scientific insights for water-efficient crop placement strategies in arid irrigation regions.

Assessing the spatiotemporal dynamics of crop production water footprint (WF) at the regional scale is critical for optimizing agricultural water resource management. However, studies quantifying WF in the Hetao Irrigation District (HID) using distributed agro-hydrological models remain limited, and integration of WF quantification with time-series models for short-term forecasting and WF-driven planting optimization is still lacking. In this study, a calibrated SWAP-WOFOST model was employed to quantify the total water footprint (WF_total), blue water footprint (WF_blue) and green water footprint (WF_green) of spring wheat, spring maize and sunflower in the HID during 2000–2017. Temporal trends were analysed using time-series techniques, and the evolution of WF_total from 2018 to 2027 was projected using the ARIMA model. Spatial WF patterns were further mapped to optimize crop allocation. The results revealed that WF_blue for all crops exhibited a continuous upward trend during 2000–2017, which consistently exceeded WF_green that showed a declining trend. Projections indicated a sustained increase in WF_total from 2018 to 2027, with spring wheat demonstrating the highest growth rate. Following crop allocation optimization, WF_total for all crops decreased significantly, accompanied by enhanced water use efficiency. This study provides scientific insights for water-efficient crop placement strategies in arid irrigation regions.

This study evaluated the performance of the AquaCrop model in simulating wheat yield, dry matter and evapotranspiration under various irrigation levels (50%, 75% and 100% water requirements) and seed densities (120–280 kg ha⁻¹) over 2 years. The model's accuracy was tested via nine ET₀ equations, including Penman–Monteith (PM), Penman–FAO (PFAO), Hargreaves–Samani (HS), Blaney–Criddle (BC), Turc, Evaporation Pan (PAN), Jensen–Haise (JH), Priestley–Taylor (PT) and FAO–radiation (RAD). The results revealed that AquaCrop effectively simulated evapotranspiration, dry matter and yield during calibration and validation. Importantly, the model demonstrated acceptable accuracy in simulating wheat yield across all evaluated ET_o calculation equations. The normalized root mean squared error (NRMSE) values were 0.08 for HS, 0.09 for Turc, 0.10 for both BC and PM, 0.11 for PT, 0.14 for both PAN and PFAO and 0.17 for JH. This study highlights the potential of using simplified ET_o equations such as HS, Turc, BC, PAN and JH instead of more complex equations such as PM, PFAO and PT as a practical approach for modelling crop growth and yield in regions with limited meteorological data. This provides a useful framework for researchers and practitioners working in water-scarce environments to simulate crop performance effectively via the AquaCrop model with reduced data requirements.

This study assessed the vulnerability of upper–middle Pleistocene aquifers in Tay Ninh Province, Vietnam. This shallow aquifer is susceptible to contamination from natural geological, climatic and anthropogenic sources, particularly agricultural activities, in the context of rapid socio-economic development in this study area. In this study, the GOD, DRASTIC and combined DRASTIC methods were used to identify vulnerable areas, particularly the susceptibility of aquifers to nitrate. The study indicates that the extended vulnerability index (DL) has low, medium and high levels of 1.4%, 72.1% and 26.5%, respectively. Moreover, the nitrate vulnerability index (DN) has low, medium and high levels of sensitivity: 29.4%, 47.8% and 22.8%, respectively. The DN index showed a strong correlation coefficient (r = 0.746) for the spatial distribution of nitrate concentration in the aquifer, which was related to different land uses. The DN multiplicative model outperformed traditional methods in evaluating the vulnerability related to the impacts of land use types. The results of this study on the vulnerability of groundwater to nitrate provide a basis for sustainable groundwater protection and land use planning in the current study area.

This study assessed the vulnerability of upper–middle Pleistocene aquifers in Tay Ninh Province, Vietnam. This shallow aquifer is susceptible to contamination from natural geological, climatic and anthropogenic sources, particularly agricultural activities, in the context of rapid socio-economic development in this study area. In this study, the GOD, DRASTIC and combined DRASTIC methods were used to identify vulnerable areas, particularly the susceptibility of aquifers to nitrate. The study indicates that the extended vulnerability index (DL) has low, medium and high levels of 1.4%, 72.1% and 26.5%, respectively. Moreover, the nitrate vulnerability index (DN) has low, medium and high levels of sensitivity: 29.4%, 47.8% and 22.8%, respectively. The DN index showed a strong correlation coefficient (r = 0.746) for the spatial distribution of nitrate concentration in the aquifer, which was related to different land uses. The DN multiplicative model outperformed traditional methods in evaluating the vulnerability related to the impacts of land use types. The results of this study on the vulnerability of groundwater to nitrate provide a basis for sustainable groundwater protection and land use planning in the current study area.

Conventional farming systems face significant challenges due to resource depletion from climate change and population growth. Alternative techniques like soilless culture (hydroponics) can produce high yields using limited space, water and no soil. This study evaluated the efficacy of a nutrient film technique (NFT)–based vertical hydroponic system for cultivating bok choy, comparing it with conventional soil-based cultivation. The experiment was conducted in a controlled greenhouse at the Centre for Protected Cultivation Technology, Indian Agricultural Research Institute, New Delhi, India. The hydroponic system used a standard Hoagland solution, while soil-based cultivation applied a recommended dose of fertilizer (76:46:83 kg N:P:K) and 100% crop evapotranspiration (ETc) via drip irrigation. Results showed the vertical hydroponic system outperformed conventional methods, with shorter growth periods, better growth parameters and higher photosynthetic activity. Over the 2022–2023 two-season cycle, hydroponics yielded 3.5–4 times more production and 3 times greater nutrient efficiency. Its water use efficiency (WUE) was 69% higher, significantly reducing water use. Additionally, it required 65% less space than traditional farming. This study demonstrates that vertical hydroponics is a sustainable, space-efficient solution for urban agriculture, offering higher yields, reduced water usage, improved efficiency and space savings compared to conventional methods.