Irrigation and Drainage最新文献

The cheap conductivity-based sensors favoured by farmers for soil moisture monitoring remain largely ignored by researchers because of their low accuracy, which results in high uncertainty regarding their utility for irrigators. In this work, conductivity measurements were compared with dielectric permittivity measurements in moisture ranges relevant to different applications. The results showed that the permittivity measurements captured moisture variability well (R² > 0.8) throughout the full range tested (0%–35%), which is consistent with the literature. Conductivity measurements consistently distinguished dry from wet conditions (p < 0.0001) and reflected moisture variability in lower ranges (R² > 0.5) but not in higher ranges (>20%). This is problematic because important monitoring thresholds such as field capacity and saturation are in the upper moisture ranges. Conductivity measurements were found to lack any meaningful utility in most applications except those relevant to distinguishing dry from wet conditions and indicating lower-range moisture patterns, such as monitoring in arid environments. This gives some merit to conductivity sensors considering their very low cost if corrosion is minimised. The described evaluation approach is suggested as an example for developers, labs and extension services to better communicate potential sensor utilities and restrictions to practitioners to improve their accessibility to decision support technologies.

Water scarcity is a significant challenge in agriculture, particularly in arid and semiarid regions. Superabsorbent polymers (SAPs), such as hydrogels, have emerged as effective tools for enhancing soil moisture retention and improving crop yield and water productivity in these environments. A two-year field study was conducted to examine the impacts of hydrogel type and application depth on soil water distribution, water productivity and spinach growth. Two types of hydrogels, polymer-based (Hydrogel-1) and small organic molecule-based (Hydrogel-2), were applied at three depths—surface (D₁), 5 cm (D₂) and 10 cm (D₃)—in a randomized block design. The results revealed that the water absorption capacity and water salinity of Hydrogel-1 were negatively correlated, whereas those of Hydrogel-2 were unaffected by salinity. Compared with that of the control, the soil moisture retention improved with deeper hydrogel application, with the Hydrogel-1 treatment at 10 cm extending irrigation intervals by 2–4 days. Hydrogel application at greater depths significantly increased spinach growth metrics, including plant height, leaf count, leaf area, root length, SPAD value and yield, resulting in the highest yield (5.7 kg/m²) and water productivity (44.8 kg/m³). The study concludes that applying hydrogels at a depth of 10 cm is optimal for maximizing resource use efficiency and water productivity in spinach grown in vertisols.

Rahimi, A, Liaghat, A, Ebrahimian, H, Ashrafi, A. Performance of surface, subsurface and trench-type drainage systems in paddy fields for non-rice farming. Irrig. Drain. 2024; 73(4): 1437–1452. https://doi.org/10.1002/ird.2971

In the affiliation section of all authors, the text ‘Department of Irrigation and Reclamation Engineering, College of Agriculture and Natural Resources, Karaj, Iran’ is not completely correct. This should have read: ‘Department of Irrigation and Reclamation Engineering, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.’

We apologize for this error.

Pressure-compensating emitters (PCE) ensure consistent flow rates and uniform irrigation in drip irrigation systems across varying pressures. However, the performance of PCE can be significantly compromised by marginal water, characterized by impurities like particulate matter, salt ions, microorganisms and organic substances. To date, research elucidating the factors contributing to PCE performance reduction with marginal water sources has been limited. This study investigated the effects of tour types of marginal waters on PCE performances, specifically saline water (rich in salt ions), high-sediment water, biogas slurry (rich in organics) and reclaimed water (containing microorganisms), under three operational pressures (0.1 MPa, 0.2 MPa, 0.3 MPa). Variations in clogging substances and diaphragm performance within the PCE flow channel were analysed. Results indicated that PCE performance declined most rapidly in saline water, followed by high-sediment water, biogas slurry and reclaimed water. Compared to clogging substances within the flow channel in reclaimed water conditions, those in biogas slurry, high-sediment water and saline water increased by 3.4%, 17.5% and 93.1%, respectively. The flow coefficient decreased by 21.1%, 32.2% and 18.0%, respectively, while the flow index increased by 5.8%, 12.5% and 50.2%, respectively. Furthermore, the elastic modulus of the diaphragm decreased by 1.8%, 13.6% and 44.1%, respectively. These results underscored that chemical ions in the water source are the most critical factor influencing PCE performance, followed by sediment and organic matter, while microorganisms have a comparatively lesser impact. Furthermore, higher pressure levels were found to contribute to improvements in PCE performance. This study offers insights into the influence of various marginal waters on PCE performance, with implications for the broader adoption and implementation of pressure-compensating drip irrigation technology in conditions involving marginal water.

To mitigate the negative effects of climate, the use of resilient agriculture is essential. This study evaluated the impact of different levels of biotic mulch on irrigated forage cactus yield, phenology and economic indices. The ‘Orelha de Elefante Mexicana’ clone was used and subjected to four levels of biotic mulch—BM (0, 5, 10 and 15 Mg ha⁻¹) in a randomised block design with four repetitions. The treatments consisted of growing forage cactus with 0, 5, 10 and 15 Mg ha⁻¹ mulch. The experiment was carried out in a semi-arid environment in Brazil (Serra Talhada, Pernambuco State) over two successive cycles (August 2020 to August 2022). The yield, cutting time, and morphophysiological, economic and water use indicators were evaluated. There was no effect of the BM level on the final forage yield. In the first experimental cycle, the treatment with 10 Mg ha⁻¹ BM brought the cutting time forward by 103°C day. The application of 15 Mg ha⁻¹ BM prolonged phenophase 2, causing an increase of 236°C day in the cycle compared with the treatment with 10 Mg ha⁻¹ BM. We concluded that mulch improved crop water and economic indicators, contributing to sustainable forage production in semiarid environments.

Résumé

Pour atténuer les effets négatifs exercés par le climat, l'utilisation d'une agriculture résistante au climat est essentielle. Cette étude a évalué l'impact de différents niveaux de paillis biotique sur le rendement, la phénologie et les indices économiques du cactus fourrager irrigué. Le clone ‘Orelha de Elefante Mexicana’ a été utilisé et soumis à quatre niveaux de paillis biotique—PB (0, 5, 10 et 15 Mg ha⁻¹) dans un plan en blocs aléatoires avec quatre répétitions. Les traitements comprennent la cultivation du cactus fourrager avec le paillis de 0, 5, 10 et 15 Mg ha⁻¹. L'expérience a été menée dans un environnement semi-aride au Brésil (Serra Talhada, État du Pernambouc) sur deux cycles successifs (d'août 2020 à août 2022) dans le champ agricole de l'UFRPE/UAST. Le rendement, le temps de coupe, les indicateurs morpho-physiologiques, ainsi que les indicateurs économiques et d'utilisation de l'eau ont été évalués sur deux cycles. Il n'y a pas eu d'effet des niveaux de PB sur le rendement final du fourrage. Lors du premier cycle expérimental, le traitement avec 10 Mg ha⁻¹ de PB a avancé le temps de coupe de 103°C jour. L'application de 15 Mg ha⁻¹ de PB a prolongé la phase phénologique 2, entraînant une augmentation de 236°C jour du cycle par rapport au traitement avec 10 Mg ha⁻¹ de PB. Nous avons conclu que l'utilisation de paillis a amélioré les indicateurs économiques et hydriques de la culture, contribuant ainsi à une production fourragère durable dans les environnements semi-arides.

Surface water is essential for agricultural, domestic and industrial production worldwide. Monitoring surface dynamics is crucial for sustainable ecosystems and global water resources. Importance of monitoring surface water dynamics is even more pronounced in the semi-arid regions worldwide. An analysis of surface water extent and volume change patterns has been conducted, comparing these dynamics with alterations in precipitation patterns within a basin in Central Bundelkhand, a semi-arid region in the Central India prone to droughts. To map the waterbodies, we leveraged Sentinel-1 SAR data using an automated mapping framework and utilised DEM dataset to extract bathymetry using interpolation with modifications using water persistence. Analysis revealed a lag in surface water peak water level with respect to accumulated rainfall by 2–3 months. Furthermore, we have categorised the water bodies into small, medium and large by surface area and found that smaller water bodies show a higher intra-annual variance, while medium and large water bodies show a lower intra-annual variance. The findings suggest that smaller communities reliant on smaller water bodies are at a higher risk from climate variability in the region and a delay in attaining peak surface storage across the basin causes further challenges to water management.

Les eaux de surface jouent un rôle important dans l'agriculture, la production domestique et industrielle à l'échelle mondiale. La surveillance de la dynamique de surface est importante du point de vue des écosystèmes durables et des ressources en eau dans le monde entier. L'importance de la surveillance de la dynamique des eaux de surface est encore plus prononcée dans les régions semi-arides du monde entier. Le Bundelkhand est une région semi-aride du centre de l'Inde souvent en proie à des sécheresses. Nous avons analysé les schémas d'étendue et de changement de volume des eaux de surface et comparé la dynamique avec les changements dans les schémas de précipitations sur un bassin du centre du Bundelkhand. Nous avons exploité les données SAR de Sentinel-1 pour cartographier les plans d'eau de la région à l'aide d'un cadre de cartographie automatisé et utilisé l'ensemble de données DEM pour extraire la profondeur bathymétrique en utilisant l'interpolation avec des modifications utilisant la persistance de l'eau. Notre analyse a révélé un retard de réponse des eaux de surface par rapport aux précipitations de 2 à 3 mois. En outre, nous avons classé les masses d'eau en petites, moyennes et grandes masses d'eau selon le Centre national d'informatique de l'eau et avons constaté que les petites masses d'eau ont une variance intra-annuelle plus élevée et que les masses d'eau moyennes et grandes ont une variance intra-annuelle plus faible. Les résultats de l'étude suggèrent que les petites communautés qui dépendent de plans d'eau de petite taille sont plus exposées aux variations climatiques dans la région et qu'un retard d

A factorial experiment with three replicates was designed to investigate the effects of potassium silicate (0, 1, 2 and 3 g L⁻¹) on camelina under three irrigation regimes (full irrigation, restricted irrigation from silicle formation and restricted irrigation from the beginning of flowering). Compared with full irrigation, restricted irrigation from the beginning of the flowering and silicle formation stages caused reductions of 5% and 11%, respectively, in the oil content and of 48% and 68%, respectively, in the oil yield (oil content 33% and oil yield 736 kg ha⁻¹). The drought stress regimes increased the saturated fatty acid (SFA) content, whereas the polyunsaturated fatty acid (PUFA) content, the PUFA/SFA (P/S) ratio and the monounsaturated fatty acid/SFA (M/S) ratio decreased. Under water-limited conditions, 3 g L⁻¹ potassium silicate significantly mitigated the negative effects of drought stress and increased the oil yield and content. Moreover, spraying 2 and 3 g L⁻¹ potassium silicate increased the PUFA, P/S and M/S but decreased the SFA. Erucic acid, which was increased by the restricted irrigation treatments, decreased in response to potassium silicate application. Overall, the application of potassium silicate is a suitable measure for camelina cultivation under water-limited conditions, as it mitigates the adverse effects of drought.

Une expérience factorielle avec trois répétitions a été conçue pour étudier les effets du silicate de potassium (0, 1, 2 et 3 g L⁻¹) sur la caméline dans le cadre de trois régimes d'irrigation (irrigation complète, irrigation restreinte à partir de la formation de silicules et irrigation restreinte dès le début de la floraison). Par rapport à l'irrigation complète, une irrigation restreinte dès le début de la floraison et de la formation des silicules a entraîné des réductions de 5% et 11% respectivement de la teneur en huile et de 48% et 68% respectivement du rendement en huile (teneur en huile: 32,97% et rendement: 736 kg ha⁻¹). Les régimes de stress lié à la sécheresse ont augmenté la teneur en acides gras saturés (AGS), tandis que la teneur en acides gras polyinsaturés (AGPI), le rapport entre les acides gras polyinsaturés et saturés (P/S) et le rapport entre les acides gras monoinsaturés et les acides gras saturés (M/S) ont diminué. Dans des conditions de ressources en eau limitées, 3 g L⁻¹ de silicate de potassium atténuaient considérablement les effets négatifs du stress causé par la sécheresse et augmentaient le rendement et la teneur en huile. De plus, la pulvérisation de 2 et 3 g L⁻¹ de silicate de potassium a augmenté le rapport entre les acides gras polyinsaturés (AGPI), P/S et M/S, mais a diminué les acides gras saturés (AGS). L'acide érucique, qui a été augmenté par les traitements d'irrigation limités, a diminué en réponse à l'application de silicate de potassium. Dans l'ensemble, l'application

Rainfed agriculture is crucial for ensuring global food and water security, and supplementary irrigation is an effective means of improving the economic benefits in rainfed agricultural regions. This study proposes a novel uncertain optimization approach to optimize supplementary irrigation areas in rainfed agricultural regions. The approach incorporates multi-objective linear programming, interval linear programming, fuzzy goal programming and stochastic expected value programming. In the proposed interval multi-fuzzy goal stochastic expected-value programming, uncertainties are expressed in the form of discrete intervals, probability distributions and fuzzy goals. This approach, which considers the randomness of precipitation during the optimization process and allocates limited irrigation water resources to different subareas and crops, was applied to a case study of crop irrigation area planning in Guyuan City, Ningxia Hui Autonomous Region, northwestern China. The maximum economic benefits and the minimum sum of the Gini coefficients among the different subareas and crops were regarded as the planning objectives, and a series of optimal irrigation areas with different crops and subareas under different water levels were obtained. The optimization results revealed that vegetables and fruits consumed large amounts of irrigation water to increase their economic benefits. In addition, allocating a large amount of irrigation water to wheat is essential to decrease the Gini coefficient and meet food security constraints, particularly at extremely low water levels. Compared with current management, the optimized irrigation area decreased by 30%, the crop water deficit index increased by 9%, the economic benefits increased by 3% and the total Gini coefficient of crops decreased by 17%, indicating that the optimization approach could fairly and reasonably allocate irrigation water resources. Our research provides a mathematical approach for decision-makers to plan supplementary irrigation areas in rainfed agricultural regions.

Water scarcity and low irrigation efficiency are the main factors causing yield losses in spring wheat in arid areas. To propose optimised irrigation scheduling for spring wheat in the arid areas of Ningxia, China, we first calibrated the SWAP (soil–water–atmosphere–plant) model and then utilised the well-tested SWAP model during three typical rainfall years to evaluate the 542 irrigation schemes. The results showed that the model performed well in simulating the plant height, leaf area index (LAI) and biomass of spring wheat under different water stress conditions. The R² values of the above three crop growth indicators were all greater than 0.89, and the normalised root mean square error (NRMSE) was less than 18% in the validation period. Additionally, the model achieved a high degree of accuracy in simulating the soil water content, evapotranspiration and yield, with RMSEs of 2%, 31 mm, and 326 kg/ha, respectively. The total irrigation amounts of 290, 320 and 350 mm with five, six and six irrigation times in the wet, average, and dry years, respectively, could achieve relatively high yields as well as improved water use efficiency (WUE) and irrigation water use efficiency (IWUE). The results can provide useful information for the efficient utilisation of irrigation water resources in arid areas.