Search Results (276)

Efficient water management is critical for sustainable dryland agriculture, especially under increasing water scarcity and climate variability. Shanxi Province, a typical dryland region in northern China characterized by pronounced climatic variability and limited soil water availability, faces severe challenges due to uneven precipitation and restricted water resources. This study aimed to evaluate the spatiotemporal dynamics of soil water resources and their coupling with crop water demand under different hydrological year types. Using daily meteorological data from 27 stations (1963–2023), we identified dry, normal, and wet years through frequency analysis. Soil water resources were assessed under rainfed conditions, and water deficits of major crops—including millet, soybean, sorghum, winter wheat, maize, and potato—were quantified during key reproductive stages. Results showed a statistically significant declining trend in seasonal precipitation during both summer and winter cropping periods (p < 0.05), which corresponds with the observed intensification of crop water stress over recent decades. Notably, more than 86% of daily rainfall events were less than 5 mm, indicating low effective rainfall. Soil water availability closely followed precipitation distribution, with higher values in the south and west. Crop-specific analysis revealed that winter wheat and sorghum had the largest water deficits in dry years, necessitating timely supplemental irrigation. Even in wet years, water regulation strategies were required to improve water use efficiency and mitigate future drought risks. This study provides a practical framework for soil water–crop demand assessment and supports precision irrigation planning in dryland farming. The findings contribute to improving agricultural water use efficiency in semi-arid regions and offer valuable insights for adapting to climate-induced water challenges. Full article

An integrated process scheme is developed for valorizing filtered liquid digestates (FLD) from an industrial anaerobic digestion (AD) plant treating dairy-processing effluents with relatively low nutrient concentrations. The process scheme involves FLD treatment by nanofiltration (NF) membranes, followed by struvite recovery from the NF-retentate. An NF pilot unit (designed for this purpose) is combined with a state-of-the-art NF/RO process simulator. Validation of simulator results with pilot data enables reliable predictions required for scaling up NF systems. The NF permeate meets the standards for restricted irrigation and/or reuse. Considering the significant nutrient concentrations in the NF retentate (i.e., ~500 mg/L NH4-N, ~230 mg/L PO4-P), struvite recovery/precipitation is investigated, including determination of near-optimal processing conditions. Maximum removal of nutrients, through production of struvite-rich precipitate, is obtained at a molar ratio of NH₄:Mg:PO₄ = 1:1.5:1.5 and pH = 10 in the treated stream, attained through the addition of Κ₂HPO₄, ΜgCl₂·6H₂O, and NaOH. Furthermore, almost complete struvite precipitation is achieved within ~30 min, whereas precipitate/solid drying at modest/ambient temperature is appropriate to avoid struvite degradation. Under the aforementioned conditions, a significant amount of dry precipitate is obtained, i.e., ~12 g dry mass per L of treated retentate, including crystalline struvite. The approach taken and the obtained positive results provide a firm basis for further development of this integrated process scheme towards sustainable large-scale applications. Full article

Groundwater is the main source of water for both domestic and agricultural use in arid regions. This study assessed the hydrogeochemical characteristics and suitability of groundwater for drinking and irrigation in Kenya’s Ewaso Ng’iro–Lagh Dera Basin. A total of 129 borehole groundwater samples were collected and analyzed for pH, electrical conductivity (EC), total hardness, and major ions. The groundwater was found to be mostly neutral to slightly alkaline and ranged from marginal to brackish in salinity. The dominant water type is Na-HCO₃, with the ionic order Na⁺ > Ca²⁺ > Mg²⁺ > K⁺ and HCO₃⁻ > Cl⁻ > SO₄²⁻ > NO₃⁻. Mineral saturation indices indicate that the water is undersaturated with gypsum and anhydrite but is saturated with calcite, dolomite, and aragonite. Groundwater chemistry is primarily influenced by ion exchange, the mixing of fresh and paleo-saline water, and rock weathering processes. The water quality index (WQI) reveals that 80.5% of groundwater is suitable for drinking. The rest have high levels of sodium, EC, and bicarbonate. Thus, they are not suitable. The irrigation water quality index (IWQI) places most samples in the moderate-to-severe restriction category due to high salinity and sodicity. These findings highlight the importance of properly treating groundwater before use. Full article

Soil salinization in coastal areas is a serious problem restricting agricultural development. This field study aimed to explore the effects of flue gas desulfurization gypsum (FGDG) and coal fly ash (CFA) in combination with irrigation on coastal saline soils in China. Six different treatments (C1–C4: FGDG 4.5–15.0 t/hm²; C5 and C6: FGDG 4.5 t/hm² combined with CFA 2.0 and 3.5 t/hm²) were established, and soil properties such as pH, electrical conductivity (EC), and organic matter (OM) content were analyzed. The results showed that compared with the control group, the addition of FGDG (4.5 t/hm² to 15 t/hm²) slightly increased the soil pH, and the combined application of FGDG and CFA made the soil pH closer to neutral. The application of FGDG combined with two rounds of irrigation could reduce the soil EC, and the mixed application of FGDG and CFA further reduced the soil EC by about 6.7% in the 0–20 cm layer. The application of FGDG combined with irrigation showed no significant effect on the soil OM content. In general, the moderate application of FGDG and CFA can effectively improve the physicochemical properties of soil, potentially contributing to more sustainable agricultural practices in coastal regions. Full article

Biodegradable mulch films not only provide similar field benefits to conventional mulch films but also degrade naturally, rendering them an effective alternative to traditional polyethylene mulch films for mitigating “white pollution”. However, recent studies have focused on the material selection and soil ecological impacts of biodegradable mulch films, while their effects on soil water temperature regulation and root architecture in drip-irrigated rice cultivation remain unclear. To address this research gap, in this study, various treatments including no mulch (NM), conventional plastic mulch (PM), and four types of biodegradable mulch films (BM-W₁, BM-B₁, BM-B₂, and BM-B₃) were established, and their effects on the soil hydrothermal flux, root architecture, biomass accumulation, and resource use efficiency of drip-irrigated rice were analyzed at different growth stages. The results indicated the following: (1) Compared with the NM treatment, film mulching increased the soil hydrothermal fluxes and water retention capacity, thereby promoting root growth and biomass accumulation, ultimately increasing the effective panicle number and grain yield. (2) Among the biodegradable film treatments, BM-B₃ (with a degradation period of 105 days) maintained relatively higher soil temperature for a longer duration, which increased surface root distribution in the mid-to-late growth stages, further improving fine root growth and biomass accumulation, consequently enhancing both yield and water use efficiency. In contrast, BM-B₁ and BM-B₂ exhibited excessively rapid degradation rates, leading to significant fluctuations in soil moisture and temperature, thereby negatively affecting water supply and nutrient uptake and ultimately restricting root growth and development. (3) The entropy weight (EW) technique for order of preference by similarity to ideal solution (TOPSIS) model results revealed that although the PM treatment was more advantageous in terms of soil temperature, root dry weight, and soil moisture content, BM-B₃ provided a slightly higher yield than the PM treatment did and offered the advantage of biodegradability, making it a preferred alternative to conventional mulch film. In summary, this study revealed the mechanism by which biodegradable mulch films enhanced biomass accumulation and yield formation in drip-irrigated rice production by optimizing soil hydrothermal dynamics and root architecture, thereby exploring their potential as replacements for conventional mulch films. These findings provide a theoretical basis for the efficient and sustainable production of drip-irrigated rice in arid regions. Full article

Cowpea (Vigna unguiculata (L.) Walp.) is a vital legume crop recognized for its nutritional value and adaptability to various growing conditions. However, exposure of cowpea to drought stress during the early growth stages can significantly restrict growth and yield potential. Therefore, identifying cowpea genotypes tolerant to drought during early growth and development is essential for maintaining yield potential. This study characterized 15 diverse cowpea genotypes for various physiological, pigment, and morphological traits that may contribute to drought tolerance. At the V2 stage, the cowpea genotypes were subjected to two moisture regimes: control (100% irrigation) and drought (50% irrigation) for 22 days to assess trait responses and their relationship to drought tolerance. Drought-stressed plants decreased stomatal conductance by 79%, negatively correlating with a 2.9 °C increase in canopy temperature. Under drought, the photochemical reflectance index (PRI) was strongly associated with the quantum yield of PSII and electron transport rate. Shoot biomass decreased by 51% and root biomass by 32% under drought. Leaf area and shoot weight were correlated with root traits such as total length, surface area, and weight. Among all genotypes, 280785-11 and UCR 1004 demonstrated superior rooting vigor under drought, emphasizing their efficiency in resource utilization. These findings highlight the relevance of utilizing drought-adaptive traits to improve early-season drought tolerance. Full article

The salinization of cultivated soil in arid zones is a core obstacle restricting the sustainable development of agriculture, particularly in regions like Xinjiang, China, where extreme aridity and intensive irrigation practices exacerbate salt accumulation through evaporation–crystallization cycles. Conventional drip irrigation, while temporarily mitigating surface salinity, often leads to secondary salinization due to elevated water tables and inefficient leaching. Recent studies highlight the potential of integrating drip irrigation with subsurface drainage systems to address these challenges, yet the synergistic mechanisms governing ion transport dynamics, hydrochemical thresholds, and their interaction with crop physiology remain poorly understood. In this study, we analyzed the effects of spring irrigation during the non-fertile period, soil hydrochemistry variations, and salt ion dynamics across three arid agroecosystems in Xinjiang. By coupling drip irrigation with optimized subsurface drainage configurations (burial depths: 1.4–1.6 m; lateral spacing: 20–40 m), we reveal a layer-domain differentiation in salt migration, Cl⁻ and Na⁺ were leached to 40–60 cm depths, while SO₄²⁻ formed a “stagnant salt layer” at 20–40 cm due to soil colloid adsorption. Post-irrigation hydrochemical shifts included a 40% decline in conductivity, emphasizing the risk of adsorbed ion retention. Subsurface drainage systems suppressed capillary-driven salinity resurgence, maintaining salinity at 8–12 g·kg⁻¹ in root zones during critical growth stages. This study establishes a “surface suppression–middle blocking–deep leaching” three-dimensional salinity control model, providing actionable insights for mitigating secondary salinization in arid agroecosystems. Full article

Overextraction of groundwater, as well as rapidly changing land use patterns, climatic change, and anthropogenic activities, in the densely populated Melur of Tamil Nadu state in India, has led to aquifer degradation. This study maps the groundwater potential (GWPZ) by evaluating 678 km² of this region in the Analytical Hierarchy Processes (AHP) and by using remote sensing and GIS tools as part of SDG 6 for the sustainable management of drinking, irrigation, and industrial uses for future generations. Data information layers, such as aquifer (a), topography (t), lineaments (l), land-use/land-cover (LuLc), soil (s), rainfall (r), and drainage (d) characteristics, separated the study area between poor and excellent groundwater potential zones with 361 km² or 53% of the study area remaining as low GWP and the prospective excellent groundwater potential zone covering only 9 km² (1.3% of total area). The integrated approach of the GWPZ and Water Quality Index (WQI) can effectively identify different zones based on their suitability for extraction and consumption for better understanding. This study also evaluates the performance of three machine learning models, such as Random Forest (RF), Gradient Boosting, and Support Vector Machine (SVM), based on a classification method using the same layers that govern the groundwater potential. The results indicate that both the RF model and Gradient Boosting achieved 100% accuracy, while SVM had a lower accuracy of 50%. Performance metrics such as precision, recall, and F1-score were analyzed to assess classification effectiveness. The findings highlight the importance of model selection, dataset size, and feature importance in achieving optimal classification performance. Results of this study highlight that the aquifer system of Melur has a low groundwater reserve, and it requires adequate water resource management strategies such as artificial recharge, pumping restriction, and implementation of groundwater tariffs for sustainability. Full article

Western Kazakhstan is susceptible to desertification, with surface water resource scarcity constraining agricultural development. Groundwater has substantial potential as a reliable and secure alternative to other water resources, particularly for irrigation, which is required to ensure food security. Eight aquifer segments with an exploitable potential of 0.24 km³/year have been identified for the integrated assessment of groundwater’s suitability for irrigation. The assessment criteria included hydro-chemical groundwater characteristics and irrigated land soil-reclamation conditions. The primary objectives of this study were to assess the groundwater quality for irrigation and to develop a practical operation scheme for rational groundwater use in water-saving irrigation technologies and optimize agricultural crop cultivation. Approximately 90% of the groundwater in these aquifer segments was found to be suitable for irrigation, with a total amount of 6520 thousand m³/day and a salinity of up to 1 g/L, and an additional 12,971 thousand m³/day had a water salinity of up to 3 g/L. Only approximately 10% had TDS values above 3 g/L and up to 6.5 g/L, categorized as conditionally suitable for restricted customized agricultural crop irrigation. Irrigated land development by complex soil desalination agro-reclamation operations enabled the use of brackish water for irrigation. The integrated analysis allowed the development of drip irrigation and sprinkling system irrigation schemes that gradually replaced wasteful surface irrigation. The irrigated land prospective area recommended for groundwater irrigation development is 653 km², with the further restructuring of cultivated areas, reducing the number of annual grasses and grain crops and increasing the number of vegetables, potatoes, and perennial grasses. Full article

The shortage of water resources, the serious harm of soil salinization and the large loss of nitrogen caused by excessive application of nitrogen fertilizer are the main factors restricting the sustainable development of agriculture in irrigation areas. Based on this factor, saline irrigation area needs to find a soil improvement method that can keep water and restrain salt, increase fertilizer and increase production under the condition of reducing the amount of nitrogen fertilizer application, which is of great practical significance for promoting the development of saline soil improvement technology and high and stable grain yield. In this paper, the physical and chemical properties, temporal and spatial dynamic distribution of water, fertilizer and salt content, sunflower yield and water and nitrogen use efficiency of saline soil in Hetao irrigation area were studied by means of field experiment and numerical analysis, and the improvement mechanism and water, fertilizer and salt regulation effects of different soil amendments on saline soil in irrigation area were revealed. The results showed that the biochar treatment group significantly reduced soil pH and conductivity, effectively inhibited salt accumulation in the soil, and increased soil organic matter content and nutrient content such as total nitrogen, available phosphorus and available potassium. The porous structure of biochar enhances the soil’s water retention capacity and reduces soil water evaporation. The combination of carbon and nitrogen application treatment not only reduced nitrogen loss but also prevented salt from moving to the soil surface, further optimizing the soil environment. In terms of crop growth and yield, the group treated with carbon nitrogen combined application showed the best growth performance of sunflowers, with rapid plant height growth, lush leaves, and the highest leaf area index. The overall growth momentum was stronger than other treatment groups. Full article

Water and energy use, along with wastewater reuse, are critical for sustainable industrial production. This study develops a decision support framework (DSF) to assess wastewater treatment and reuse, incorporating Water and Carbon Footprint indicators. The framework is applied to a Greek brewery producing 1.4 × 10⁶ hL of beer annually, with a total water consumption of 5.6 hL per hL of beer and an in-house wastewater treatment plant (WWTP). The WWTP consumes over 40% more energy than expected, indicating a need for efficiency improvements. An advanced wastewater treatment method is proposed, capable of treating 43% of the total wastewater volume, with 3% covering the brewery’s utility water demand and the rest allocated to restricted irrigation. This reduces the operational Water Footprint by 12% and the supply chain Water Footprint by 1%, while increasing energy use by 3%. The optimal scenario, integrating water reuse and energy efficiency improvements, results in a 35% reduction in the Carbon Footprint, a 10% decrease in the operational Water Footprint, and a 1% reduction in the supply chain Water Footprint. The DSF provides a structured approach for industries to optimize sustainability by balancing water reuse with energy efficiency. Full article

Pump station engineering is extensively utilized in water supply and drainage, as well as agricultural irrigation. Due to its geographical advantages and significant comprehensive benefits, the construction of pumping stations in coastal areas has gained substantial attention in recent years. Adverse flow conditions caused by various factors negatively affect the inlet flow regime of pumps, becoming a key factor that restricts the operating life and further development of pump station systems. Optimizing the flow regime in the forebay is crucial for enhancing overall engineering quality, minimizing pump performance degradation, and reducing the risks of cavitation and vibration. This study investigates the flow characteristics of the forebay by combining the Navier–Stokes equations and the $k-\epsilon$ RNG turbulence model. The analysis focuses on the internal flow field, transverse flow before the inlet channel, and the uniformity of flow velocity distribution after the inlet channel. Numerical simulations are validated through physical model tests. We examine the flow characteristics in the forebay, analyze the causes of internal flow disorder, and propose a reasonable and practical rectification scheme for the forebay. Additionally, we elucidate the mechanism of flow state optimization through partition walls. The findings indicate that with the optimal partition wall length, the average elimination rate of transverse flow velocity before the pump station inlet channel reached 48.3%, and the uniformity of flow velocity distribution after the inlet increased by 3.24%. These research findings contribute to mitigating cavitation and vibration in water pump units, providing theoretical support for the safe operation of coastal pumping stations. Full article

Kentucky bluegrass (KBG) has poor seed establishment in the fall when used as a perennial groundcover in corn production. This study was conducted to investigate the effect of various seed treatments and soil amendments on the establishment of KBG under drought and non-drought conditions, simulated in a growth chamber. The effect of seed treatments, soil amendments, and irrigation frequency on KBG germination and shoot dry weight were measured over 21 days in a controlled environment at 21 °C, 50% RH, and exposure to a constant red light. The treatments were the Hydroloc seed treatment, a lime soil amendment, the Pivot Bio seed treatment, an ammonium nitrate soil amendment, a gibberellic acid seed treatment, osmotic seed priming, and an untreated control. The layout was a randomized complete block design, with two irrigation frequencies (restricted and full irrigation) and four replications (blocks). The irrigation treatments were applied to whole plots and the seed treatments were applied to subplots. The entire experiment was repeated four times. Irrigation affected the germination of all the seed treatments, but the size of the effect depended on the seed treatment applied. The control and Hydroloc treatments did not have significantly different dry shoot weights, while all the other treatments had significantly different dry shoot weights when comparing the irrigation regimes. The Hydroloc treatment significantly outperformed all the other treatments in regard to the restricted and full irrigation regime. These results indicate that the Hydroloc seed treatment improves KBG germination and shoot dry weight in drought and non-drought conditions, promoting KBG establishment in a wide range of soil moisture conditions. Full article

Recently, the intensification of the contrast between Taiwan’s wet and dry seasons due to climate change has led to stringent water use restrictions in agriculture, significantly impacting Taiwan’s primary staple crop, rice. This necessitates the development of effective agricultural management strategies to ensure the resilience of Taiwan’s agriculture. Therefore, we simulated potential challenges in rice cultivation due to climate change under specific conditions: flooded cultivation and soil water tension levels of −20 and −40 kPa. At −40 kPa, the soil becomes excessively dry, causing severe soil surface cracking. This results in a 20% reduction in plant height and a 30% decrease in yield compared to flooded cultivation. At −20 kPa, plant height and yield are comparable to those under flooded conditions. In resource efficiency, flooded cultivation demonstrates low irrigation water use efficiency (0.22 and 0.42 kg/m³) due to sustained high water levels. Conversely, the condition with −20 kPa shows the highest irrigation water use efficiency (2.15 and 2.16 kg/m³) with no significant difference in nitrogen use efficiency compared to flooded management. Although the irrigation water use efficiency under −40 kPa is better than flooded management (0.87 and 1.02 kg/m³), the nitrogen utilization efficiency is significantly low. Irrigation under the condition of −20 kPa climate change does not reduce yields and offers additional benefits. This strategy ensures stable crop production and conserves water resources for crop cultivation during the dry season, providing an effective means to stabilize production and mitigate the impacts of climate change on Taiwan’s agriculture. Full article

To improve the utilization rate of water resources in irrigation areas, this study established an uncertain water resource optimal allocation model considering the reuse of return flow, and it analyzed the impact of return flow reuse on irrigation efficiency, crop planting structure, and water resource allocation in irrigation areas. If only the optimal allocation of irrigation diversion is carried out, the net profit for the current years, short-term (2021–2040) planning years, and long-term (2041–2060) planning years will increase by USD [18.27, 24.18], [2.20, 2.47], and [3.02, 3.43] million, respectively, and the total planting area in the current years, short-term planning years, and long-term planning years will increase by 900 ha, 700 ha, and 1000 ha, respectively. Restricted by the total amount of irrigation water diversion, the irrigation water resources in the current years and the planning years are in deficit. When the channel return flow is optimized, the net profit of the current years and the short-term and long-term planning years will increase by USD [7.14, 7.97], [5.08, 5.63], and [4.4, 4.81] million, respectively. The total planting area in the current years and short-term and long-term planning years will increase by 2.6, 1.9, and 1.6 thousand ha, respectively, and the amount of irrigation water diversion will decrease by [12, 18], [18, 24], and [20, 26] million m³, respectively. Reasonable and optimized use of channel return flow can not only improve the irrigation efficiency of irrigation areas and avoid the impact of return flow discharge on the water quality of the Yellow River, but it can also reduce the cost of water extraction and save water resources. Full article