Search Results (80)

Strategic petroleum reserves are critical for energy security. In Japan, 0.5 million kiloliters of crude oil (12% of the state-owned reserves) is stored using underground rock-cavern tanks, which comprise unlined horizontal tunnels bored into bedrock. Crude oil is held within the tank by water inside the tank, the pressure of which is kept higher than that of the crude oil by natural groundwater and irrigation water. This study applied microbial DNA-based monitoring to assess the water environments in and around national petroleum-stockpiling bases (the Kuji, Kikuma, and Kushikino bases) using the rock-cavern tanks. Forty-five water samples were collected from the rock-cavern tanks, water-supply tunnels, and observation wells. Principal-component analysis and hierarchical clustering indicated that microbial profiles of the water samples reflect the local environments of their origins. Particularly, the microbial profiles of water inside the rock-cavern tanks were distinct from other samples, revealing biological conditions and hence environmental characteristics within the tanks. Moreover, the clustering analysis indicated distinct features of water samples that have not been detected by other monitoring methods. Thus, microbial DNA-based monitoring provides valuable information on the in situ environments of rock-cavern tanks and can serve as an extremely sensitive measurement to monitor the underground oil storage. Full article

Groundwater storage refers to the water stored in the pore spaces of underground aquifers, which has been increasingly affected by both climate change and anthropogenic activities in recent decades. Therefore, monitoring their changes and the factors that affect it is of great importance. Although the influence of natural factors on groundwater is well-recognized, the impact of human activities, despite being a major contributor to its change, has been less explored due to the challenges in measuring such effects. To address this gap, our study employed an integrated approach using remote sensing and the Google Earth Engine (GEE) cloud-free platform to analyze the effects of various anthropogenic factors such as built-up areas, cropland, and surface water on groundwater storage in the Lake Urmia Basin (LUB), Iran. Key anthropogenic variables and groundwater data were pre-processed and analyzed in GEE for the period from 2000 to 2022. The processes linking these variables to groundwater storage were considered. Built-up area expansion often increases groundwater extraction and reduces recharge due to impervious surfaces. Cropland growth raises irrigation demand, especially in semi-arid areas like the LUB, leading to higher groundwater use. In contrast, surface water bodies can supplement water supply or enhance recharge. The results were then exported to XLSTAT software2019, and statistical analysis was conducted using the Mann–Kendall (MK) non-parametric trend test on the variables to investigate their potential relationships with groundwater storage. In this study, groundwater storage refers to variations in groundwater storage anomalies, estimated using outputs from the Global Land Data Assimilation System (GLDAS) model. Specifically, these anomalies are derived as the residual component of the terrestrial water budget, after accounting for soil moisture, snow water equivalent, and canopy water storage. The results revealed a strong negative correlation between built-up areas and groundwater storage, with a correlation coefficient of −1.00. Similarly, a notable negative correlation was found between the cropland area and groundwater storage (correlation coefficient: −0.85). Conversely, surface water availability showed a strong positive correlation with groundwater storage, with a correlation coefficient of 0.87, highlighting the direct impact of surface water reduction on groundwater storage. Furthermore, our findings demonstrated a reduction of 168.21 mm (millimeters) in groundwater storage from 2003 to 2022. GLDAS represents storage components, including groundwater storage, in units of water depth (mm) over each grid cell, employing a unit-area, mass balance approach. Although storage is conceptually a volumetric quantity, expressing it as depth allows for spatial comparison and enables conversion to volume by multiplying by the corresponding surface area. Full article

From 2016 to 2021, a field experiment was conducted in the North China Plain to study the long-term effects of drip irrigation and nitrogen coupling on the growth, biomass allocation, and irrigation water and fertilizer use efficiency of short-rotation triploid Populus tomentosa plantations. The experiment adopted a completely randomized block design, with one control (CK) and six water–nitrogen coupling treatments (IF, two irrigation levels × three nitrogen application levels). Data analysis was conducted using ANOVA, regression models, Spearman’s correlation analysis, and path analysis. The results showed that the effects of water and nitrogen treatments on the annual increment of diameter at breast height (ΔDBH), annual increment of tree height (ΔH), basal area of the stand (BA_S), stand volume (V_S), and annual forest productivity (AFP) in short-rotation forestry exhibited a significant stand age effect. The coupling of water and nitrogen significantly promoted the DBH growth of 2-year-old trees (p < 0.05), but after 3 years of age, the promoting effect of water and nitrogen coupling gradually diminished. In the 6th year, the above-ground biomass of Populus tomentosa was 5.16 to 6.62 times the under-ground biomass under different treatments. Compared to the I45 treatment (irrigation at soil water potential of −45 kPa), the irrigation water use efficiency of the I20 treatment (−20 kPa) decreased by 88.79%. PFP showed a downward trend with the increase in fertilization amount, dropping by 130.95% and 132.86% under the I20 and I45 irrigation levels. Path analysis indicated that irrigation had a significant effect on the BA_S, V_S, AFP, and TGB of 6-year-old Populus tomentosa (p < 0.05), with the universality of irrigation being higher than that of fertilization. It is recommended to implement phased water and fertilizer management for Populus tomentosa plantations in the North China Plain. During 1–3 years of tree age, adequate irrigation should be ensured and nitrogen fertilizer application increased. Between the ages of 4 and 6, irrigation and fertilization should be ceased to reduce resource wastage. This work provides scientific guidance for water and fertilizer management in short-rotation plantations. Full article

The effective management of produced water (PW), a by-product of oil extraction in Oman, is essential for sustainable water use and environmental protection. PW contains petroleum residues, heavy metals, and salts, which require treatment before safe reuse. In the Nimr oil field, PW undergoes partial treatment in constructed wetlands vegetated with buffelgrass (Cenchrus ciliaris). This study investigated the reuse potential of treated PW for irrigation through two parallel field experiments conducted at Sultan Qaboos University (SQU) and the Nimr wetlands site. At the SQU site, native halophytic plants were irrigated with three water sources: treated municipal wastewater, underground water (from an on-site well), and treated produced water. At the Nimr site, irrigation was conducted using underground water and treated PW. Two soil types were used: well-draining control soil and Nimr soil from southern Oman. The treatments included: (i) PW + control soil, (ii) PW + Nimr soil, (iii) PW + gypsum (3.5 g/kg soil), (iv) PW + biochar (10 g/kg soil), (v) underground water + control soil, and (vi) treated municipal wastewater + control soil. Biochar, produced from locally sourced buffelgrass via low-temperature pyrolysis (300 °C for 3 h), and gypsum (46.57% acid-extractable sulfate) were mixed into the soil before sowing. The impact of each treatment was assessed in terms of soil quality (salinity, boron, major cations), plant physiological responses, and mineral accumulation. PW irrigation (TDS ~ 6500–7000 mg/L) led to a sixfold increase in soil sodium and raised boron levels in plant tissues to over 200 mg/kg, exceeding livestock feed safety limits. Copper remained within acceptable thresholds (≤9.5 mg/kg). Biochar reduced boron uptake, but gypsum showed limited benefit. Neither amendment improved plant growth under PW irrigation. These findings highlight the need for regulated PW reuse, emphasizing the importance of soil management strategies and alternating water sources to mitigate salinity stress. Full article

The salt distribution characteristics in arid areas are directly related to the sustainable development of agriculture. We study the characteristics of spatial changes of soil water and salt in farmland under the full anniversary of different culvert pipe arrangements and optimize the salt drainage parameters of underground drains suitable for the local area so as to promote the management of saline and alkaline land in Xinjiang. A subsurface drainpipe salinity test was conducted in the Yanqi Basin (Bayingoleng Mongolian Autonomous Prefecture, Xinjiang Uygur Autonomous Region, China) to analyze changes in soil water and salt dynamics before and after irrigation-induced salt flushing, assessing the impact of drainpipe deployment parameters. It was found that at a 1.4 m depth of burial, the maximum desalination rates of soil in different soil layers from the subsurface drainpipes in 20, 30, and 40 m spacing plots were 78.28%, 50.91%, and 54.52%, respectively. At a 1.6 m depth of burial, the maximum desalination rates of soil in different soil layers from the subsurface drainpipes in 20, 30, and 40 m spacing plots were 70.94%, 61.27%, and 44.12%. Reasonable deployment of subsurface drainpipes can effectively reduce soil salinity, increase the desalination rate, and improve soil water salinity condition. This study reveals the influence of the laying parameters of subsurface drainpipes on soil water salinity distribution characteristics in arid zones, which provides theoretical support and practical guidance for the management of soil salinization in arid zones. Full article

Water is a valuable natural resource, indispensable in the productive, economic, and social development of human beings, agriculture, and domestic and industrial uses throughout the world. Two samplings were established to evaluate the quality of surface and underground water for agricultural irrigation in the Sierra de Amula Region, Jalisco, Mexico. The first was performed during the dry season from November 2021 to April 2022, and the second was performed during the rainy season from July to September 2022 through completely random probabilistic sampling and a longitudinal descriptive study. In total, 25 surface water and 30 groundwater samples were taken. Each sample was evaluated for its pH, electrical conductivity, and ionic concentration (Ca²⁺, Mg²⁺, Na⁺, K⁺, CO₃²⁻, HCO₃⁻, CI⁻, SO₄²⁻). For data analysis, we determined the ionic concentrations and the salinity and sodicity indexes, including the electrical conductivity, pH, sodium adsorption ratio (SAR), and cationic ratio of soil structural stability (CROSS). The results indicate that the ionic concentration is mainly due to calcium bicarbonate, probably due to the geology of the region through water–rock interactions, and the pH is between 6.64 and 7.77; with respect to EC, most of the sampled sites are concentrated in medium-salinity waters of 250–750 µS cm⁻¹. The sodium adsorption ratio (SAR) showed that the waters have high ionic concentrations of calcium and magnesium and low sodium. The CROSS values were lower than the SAR values, showing that the concentration of potassium ions K⁺ is low in the evaluated waters. With respect to salinity and sodicity, the water quality of the sampled sites, both surface and groundwater, can be considered good for agricultural use. Given that it was sampled in two seasons, the concentration of ions varies in the rainy season, with the dragging of materials causing the ions to concentrate to a greater extent. This type of research benefits farmers in reducing production costs, having knowledge of water quality, and decision making. We recommend that the alkaline pH of the surface or groundwater be conditioned according to the requirements of the crop to be grown and the irrigation method to be used. Full article

Urban areas face challenges with water scarcity, and the use of non-conventional water resources for uses not requiring potable quality is being promoted more and more by governments and international agencies. However, non-conventional water resources, such as rainwater and greywater, need to be treated before use to avoid health risks and possible nuisance (smell, bacteria and algae proliferation in storage tanks, etc.). This study is aimed at demonstrating the feasibility of a system reusing treated greywater for toilet flushing, relying on a nature-based treatment technology—ground-based green façades—with limited maintenance requirements which is therefore easily replicable for decentralized treatment systems, like those of greywater reuse at building scales. The demonstrative system has been installed at the University of Jordan’s Al-Zahra dormitory in Amman and uses a degreaser as the primary treatment followed by ground-based green façade technology as a secondary treatment mechanism. The effluent is stored in an underground tank and directed to a tertiary treatment mechanism with UV lamps to remove pathogens before being reused for lawn irrigation and toilet flushing. Samples from influent and effluent were analyzed for various physical, chemical, and microbiological characteristics. The degreaser significantly reduced turbidity, TSS, total BOD₅, and total COD levels in greywater. When combined with the green wall façades, the system demonstrated high removal efficiencies, particularly for turbidity, TSS, total COD, and total BOD₅. The treated effluent met irrigation reuse standards for all the parameters, including total coliform and E. coli concentrations. The UV disinfection unit proved to be an effective post-treatment step, ensuring that water quality standards for reuse were met. The system’s overall performance highlights its ability to manage low- to medium-strength greywater. Results suggest the applied green wall system has significant potential for wider adoption in urban settings. Full article

Tomato (Jinglu 6335) was selected for assessing the impact of varying fertilizer (F:N-P₂O₅-K₂O) and aeration rates on crop quality, as well as water and fertilizer utilization efficiency during the cyclic aeration subsurface drip irrigation process. Four aeration treatments (O1, O2, O3, and S, representing aeration ratios of 16.25%, 14.58%, 11.79%, and non-aerated treatment, respectively) and three fertilizer applications (F1: 240–120–150 kg/hm², F2: 180–90–112.5 kg/hm², F3: 120–60–75 kg/hm²) were compared in a total of 12 treatments in this study. This study revealed that cyclic aerated drip irrigation improved the fruit quality. The aerated treatment resulted in increased accumulation of nitrogen, phosphorus, and potassium, with the level of aeration positively correlating with the increase in nutrient accumulation, reaching the highest values in the high aeration irrigation treatment. The highest nitrogen, phosphorus, potassium, and water use efficiency occurred under the medium fertilizer with high aeration treatment. The maximum partial productivity of the fertilizer occurred under the low fertilizer with high aeration treatment, while the minimum occurred in the high fertilizer with non-aerated treatment. Taking all factors into consideration, the high-aeration and medium-fertilizer treatment was the most effective combination for greenhouse tomatoes under the conditions in this experiment. Full article

This research examines and analyzes the measured electromagnetic characteristics of vegetal soil for Wireless Underground Sensor Networks applied to precision agriculture. For this, we used Wireless Underground Sensor Network (WUSN) technology, which consists of sensors that communicate through the soil to collect data on irrigation, such as temperature and humidity, for good plant growth. However, underground communication channels and signal transmission are required to travel through a dense and heterogeneous soil mixture. For the measurement results of the vegetal soil dielectric parameters, a precision domain sensing probe operating at 433 Mhz was used. Moreover, the different choices of capacitance, inductance, and varactor were included, with a reasonable estimation of the dielectric permittivity, ranging from 2 to 15, and an unlimited range of conductivities. Despite promising results in predicting the dielectric permittivities, several improvements were made to the mode for low permittivity values, and it was designed to accommodate a wide range of dielectric permittivities. Full article

The construction of underground reservoirs in coal goaf is a new technology aimed to realize the sustainable development of coal mining-water storage-surface ecology in arid areas of northwest China. The key to the feasibility of this technology is that underground coal mining cannot affect the near-surface aquifer, and the amount of water entering the underground reservoir must meet the needs of the coal mine. Taking Buertai Coal Mine, one of the largest underground coal mines in the world, as an example, this article used similar simulation, numerical simulation and in-situ test methods to study the height of the water-conducting fracture zone of overlying strata and water inflow of underground reservoirs. The results show that, under the repeated mining of the 22- and 42-coal seams, the maximum height of the water-conducting fracture zone is 178 m, and the distance between the near-surface aquifer and the 42 coal is about 240 m, so the mining has little effect on the near-surface aquifer. During the mining period of the 22-coal seam, the groundwater of the Zhidan and Zhiluo Formations was mainly discharged vertically, while the groundwater of the Yanan Formation was mainly a horizontal flow during the period of the 42-coal mining. In this way, the total water inflow of Buertai Coal Mine reaches 500 m³/h, which not only meets the needs of the mine, but also, the rest of the water can irrigate about 98 hectares of farmland nearby. Underground reservoirs in coal goaf could achieve sustainable development of coal mining, groundwater storage and surface ecology in semi-arid areas. Full article

In today’s ongoing rapid urban expansion, deforestation and climate changes can be observed mainly as unbalanced rain occurrence during the year, long seasons without any rain at all and unordinary high temperatures. These adverse changes affect underground water levels and the availability of surface water. In addition, quite a significant proportion of drinking water is used mainly for non-drinking purposes. With several EU countries increasingly suffering from droughts, reusing quaternary treated urban wastewater can help address water scarcity. At the European level, Regulation 2020/741 of the European Parliament and of the Council of 25 May 2020 on minimum requirements for water reuse was adopted. This regulation foresees the use of recycled wastewater mainly for agricultural irrigation. This article provides an overview of various processes, such as filtration, coagulation, adsorption, ozonation, advanced oxidation processes and disinfection, for quaternary treatment of urban wastewater in order to remove micropollutants and achieve the requirements for wastewater reuse. According to the literature, the most effective method with acceptable financial costs is a combination of coagulation, membrane filtration (UF or NF) and UV disinfection. These processes are relatively well known and commercially available. This article also helps researchers to identify key themes and concepts, evaluate the strengths and weaknesses of previous studies and determine areas where further research is needed. Full article

Soil salinization is a critical issue impacting agriculture, particularly in arid and semi-arid regions. The objective of this study was to evaluate the effects of different drip irrigation and fertilization treatments on soil water and salt dynamics, maize water use efficiency, and crop yield in the saline–alkali soils of northern Ningxia, China. Over three years, four irrigation treatments were tested: CK (flood irrigation, 810 mm), W1 (low-volume drip irrigation, 360 mm), W2 (medium-volume drip irrigation, 450 mm), and W3 (high-volume drip irrigation, 540 mm). The results demonstrate that treatments W2 and W3 significantly increased soil moisture content at depths of 0–20 cm and 60–100 cm compared to CK, facilitating uniform salt leaching in the 0–40 cm soil layer. However, in the 40–100 cm layer, decreased porosity and upward moisture movement hindered salt migration, resulting in subsurface salt accumulation. Furthermore, drip irrigation combined with fertilization significantly reduced phosphorus fixation and nitrogen leaching, enhancing nutrient availability. This led to a reduction in underground leakage and surface evaporation by up to 39.63%, while water use efficiency improved by 18.97% to 55.13%. By the third year, grain yields under drip irrigation treatments increased significantly compared to CK, with W3 showing the highest gains (up to 21.90%). This study highlights the potential of integrating drip irrigation and fertilization as an effective strategy for managing saline–alkali soils, improving water use, and increasing crop productivity, providing valuable insights for sustainable agricultural practices. Full article

Purslane has been suggested as an alternative crop suitable for human consumption due to its high content of minerals, omega-3 fatty acids, and several health-beneficial compounds. In this study, we aimed to evaluate the effect of salinity stress (tap water (control), 2000, 4000, 6000, 8000, and 10,000 mg L⁻¹), biostimulant application (putrescine and salicylic acid at 200 mg L⁻¹), and the combination of the tested factors (i.e., salinity × biostimulant application) on the growth and chemical composition of purslane plants (Portulaca oleracea L.) over two growing seasons (2022 and 2023). Irrigation with tap water and putrescine application resulted in the highest plant height, weight of aboveground and underground parts, and number of shoots per plant. In contrast, the lowest values of growing parameters were recorded under severe saline stress (10,000 mg L⁻¹), especially for the plants that were not treated with biostimulants. The same trends were observed for macronutrients (N, P, K), total carbohydrates, total chlorophylls, and vitamin C content in leaves. Moreover, nitrate and proline content was higher in plants grown under salinity stress, especially under severe stress (8000–10,000 mg L⁻¹) without biostimulant application. In general, the application of biostimulants mitigated the negative impact of salinity on plant growth and leaf chemical composition, while the effect of putrescine on the tested parameters was more beneficial than that of salicylic acid. In conclusion, this study provides useful information regarding the use of putrescine and salicylic acid as biostimulatory agents with the aim of increasing purslane growth under salinity conditions. Full article

This study was conducted to determine the irrigation water demand due to solar radiation in high-tech greenhouses using hydroponic systems in Turkey’s Mediterranean and continental climates, and to determine the annual water consumption and storage capacity with harvested rainwater. Intensive greenhouse cultivation and the recent increase in modern greenhouse cultivation were important factors in selecting the provinces for the study. The chosen provinces were Antalya and Adana, with a Mediterranean climate, and Afyonkarahisar and Kırşehir, with a continental climate. In this research, depending on the production period, the amount of water consumed per unit of area in greenhouses in Antalya, which has a Mediterranean climate, was determined to be 1173.52 L m⁻² per yr⁻¹, and in Adana, it was 1109.18 L m⁻² per yr⁻¹. In the provinces of Afyonkarahisar and Kırşehir, where a continental climate prevails, water consumption was calculated to be 1479.11 L m⁻² per yr⁻¹ and 1370.77 L m⁻² per yr⁻¹, respectively. Storage volumes for the provinces of Antalya, Adana, Afyonkarahisar and Kırşehir were found to be 438.39 L m⁻², 122.71 L m⁻², 42.12 L m⁻² and 43.65 L m⁻², respectively. For the provinces of Antalya, Adana, Afyonkarahisar and Kırşehir, the rates of rainwater harvesting and meeting plants’ water consumption were calculated to be 80.79%, 54.27%, 27.47% and 25.16%, respectively. In addition, the amount of water fee savings that could be achieved by rainwater harvesting was calculated to be USD 901.3 per yr⁻¹ for Antalya, USD 835.3 per yr⁻¹ for Adana, USD 247.6 per yr⁻¹ for Afyonkarahisar and USD 210.2 per yr⁻¹ for Kırşehir. As a result, rainwater harvesting will not only provide economic gain to enterprises but will also be important in reducing the negative effects of irregular rainfall regimes caused by climate change on underground and surface water resources. It was also concluded that enterprises should focus on popularizing rainwater harvesting. Full article

The study aims to explore saline drainage modeling in coastal saline soils, particularly focusing on subsurface pipe drainage in the Shanghai coastal area. Utilizing Hydrus-2D/3D-2.05 software, dynamic changes in soil–water–salt under various subsurface pipe laying conditions in forested areas were simulated to identify optimal schemes. Indoor and outdoor experiments demonstrated the Hydrus model’s ability to effectively simulate soil–water–salt transport processes under complex conditions. Subsequent simulations under different parameters of underground pipe laying, including burial depths (D = 0.5/0.7/0.9/1.1/1.3/1.5 m) and pipe diameters (Ø = 8/10/12 cm), further corroborated model validation. Among the analyzed schemes, those with burial depths around 0.7 m and pipe diameters under 12 cm exhibited the most substantial salinity improvement. Regression analysis highlighted a significant impact of burial depth D on cumulative salt discharge, with a coefficient of 12.812, outweighing that of pipe diameter Ø. Furthermore, subsurface pipe laying schemes demonstrated long-term benefits and cost advantages, obviating the need for additional irrigation infrastructure. These findings underscore the significance of subsurface pipe drainage in enhancing soil quality, reducing construction expenses, and optimizing land utilization, providing a valuable foundation for the Shanghai Green Corridor development and related initiatives. Full article