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Sea purslane (Sesuvium portulacastrum) was cultivated for two 90-day sequences at two spacings, and with various soil amendments, to evaluate its potential to arrest the increase in soil salinity and sodicity associated with irrigation using paper- and pulp-mill effluent. Its phytodesalination capacity (PDC) with respect to Na ranged from 162 to 226 kg/ha in the first sequence and 167 to 250 kg/ha in the second sequence; the PDC is reliable even under drought stress. Addition of amendments, in particular pressmud compost, increased the average Na+ uptake by 38%, leading to the highest PDC of 250 kg/ha for a single crop sequence. [ABSTRACT FROM AUTHOR]

Paper and pulp mills use a huge quantity of water in the manufacturing process and release a substantial quantity of salts in the effluent. The use of industrial effluents for irrigating crops due to the nutrient content in arid zones is under practice. The long-term use of paper and pulp mill effluent as a source of irrigation accumulates salts in the soil surface and rhizospheric zone. In this study, halophytes, namely Sesuvium portulacastrum, Salicornia brachiata, and Suaeda maritima were evaluated for their phytodesalination potential in paper and pulp mill effluent irrigated soil. Among these Sesuvium portulacastrum recorded the highest dry matter production (8.21 g pot-1), and the sodium accumulation was 6.7% greater than S. brachiata on 120th day. Furthermore, the soil EC was also 7.7 % lower in pots cultivated with S. portulacastrum than pots cultivated with S. brachiata. Hence, Sesuvium portulacastrum could effectively be used to phytodesalinate saline soils and ensure the sustainable cultivation of crops using paper and pulp mill effluent. [ABSTRACT FROM AUTHOR]

Purpose: Water retention capacity (WRC) is crucial for assessing the hydro-physical behavior of unsaturated soils. Dispersive soil, erodible and found mainly in arid regions, lacks sufficient WRC knowledge, hindering its stability evaluation in unsaturated state. This study aimed to explore the WRC of dispersive soil by measuring its matric suction (ψ) under coupling effects of dry density (ρd) and soluble salt content (η). Materials and method: Compacted specimens with different ρd and η were prepared. For each ρd-η case, six levels of soil mass water content were considered and the ψ was measured via filter paper method. Soil water characteristic curves (SWCCs) were fitted by van Genuchten model. Results and discussion: The WRC of dispersive soil enhances as ρd increases. Increasing η first weakens then strengthens the WRC, showing suction dependence. The air-entry value and residual state suction range within 0.95–17.8 kPa and 15.7–98.4 MPa, respectively. As for the air-entry value, increasing η from 0.3% to 2.0% decreases it from 36.0% to 58.7% when ρd increases, and its average growth rate changes from 174.5% to 265.3% when ρd exceeds 1.53 g/cm3. Increasing ρd reduces the average water loss rate of SWCC transition stage, while the impact of η is nonmonotonic, with an inflection point at 1.0%. Conclusions: The ρd and η influenced the WRC of dispersive soil individually and interactively. The effect of ρd links to the water release sequence from pores of different sizes, whereas that of η, rather complex and non-monotonic, relates to clay electrochemistry and salt phase. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• First assessment of paper chromatography using large sample sizes and microbe DNA. • Chromatogram features did not vary consistently with gradients of soil condition. • Results imply context dependent response of chromatogram features to soil condition. • Paper chromatography needs more testing before being embraced for soil assessment. Although paper chromatography is being promoted as a cost-effective tool for rapid assessment of soil health, few studies have explored the quantitative relationship between chromatogram features and soil health variables, and no studies have investigated the association between chromatogram features and microbial diversity as determined using DNA sequences. We assessed 343 soil samples from varying land uses in southwestern Australia to investigate the relationship between total organic carbon, microbial activity and diversity, salinity and pH levels and 12 chromatogram features. Spearman's correlations and variance partitioning were used to detect relationships. Although total organic carbon and microbial activity displayed the strongest correlations with chromatogram features, they were not associated with greater development of radial features and median zone radius as expected. This was in contrast to what has been previously reported, implying context dependent responses of chromatogram features to gradients in soil variables. Microbial community structure was found to explain changes in chromatogram features better than the measured soil variables. These results indicate that further studies are necessary before paper chromatography is embraced as a tool for soil health assessment, and raises questions regarding the use of chromatography by community groups as a tool to measure soil health. [ABSTRACT FROM AUTHOR]

Along with sea-level rise, one of the most detrimental effects of climate change, is salinity leakage, which significantly affects agricultural activities throughout most of the world. This occurrence is becoming increasingly dangerous. The purpose of this study was to use Geographical Information Systems (GIS) to assess the current situation of agricultural lands in the province of Al-Diwaniyah, by employing GIS to document the salt-affected sites and arrive at the most important criteria affecting those lands as well as build an application model for suitability to clarify the affected sites and come up with paper and digital maps. To accomplish this, the study relied on the available data by extrapolating and analyzing remote sensing images using salt equations to analyze the Landsat 8 satellite images, after which these data were subjected to spatial statistical treatment in ArcGIS software. Moreover, 20 samples were taken from ground sampling points and subjected to laboratory analysis to compare and document the results. The research resulted in the creation of an up-to-date database for the locations of salt ratio growth or decrease in the province of Al-Diwaniyah, which can be relied on, starting from and expanding in the future. Land maps, both paper and digital, have been created and can be used and inferred. The findings demonstrated the model's ability to steadily discriminate among all salinity groups while maintaining consistency with the ground truth data. Each of the four major salinity categories was highlighted. The best-performing indicators were used to build the MLR model, which was then used to anticipate soil salinity. The salt levels may be determined by the MLR combining NDVI and SI-5 with a high correlation value (R2 = 75.29%). Finally, it is shown that by combining spectral indicators with field measurements, it is possible to chart and forecast soil salinity on a large scale. [ABSTRACT FROM AUTHOR]

Soil salinity is a global challenge emanating from climatic changes, depletion of fresh water reserves and extensive irrigation practices among other factors. Soil salinization still remains a huge concern in the realization of sustainable agricultural production. While emphasis has been placed on the food crops, forage production, which is an important component of the food chain, is affected as well. The aim of this study was to evaluate the morphological and physiological response to salinity stress in diploid cultivars and auto-induced tetraploid lines of annual ryegrass (Lolium multiflorum spp. multiflorum). Diploid seeds and their induced tetraploid counterparts were germinated on filter paper moistened with different concentrations of sodium chloride (NaCl) solutions, and seedlings were treated with 500 mM NaCl for 10 days in controlled conditions. The effect of different salt concentrations on germination and seedlings was studied. Results showed that seeds from the induced tetraploid lines despite being bigger had higher germination index and lower median germination time (T50) values compared to the diploid progenitors. At the seedling stage, increase in the ploidy level had a role in conferring improved tolerance to salinity stress. The induced tetraploid lines had an advantage over their diploid counterparts as the induced tetraploid lines had significant reduction in their growth in response to salinity stress, higher relative water content and antioxidant activities. [ABSTRACT FROM AUTHOR]

This work presents a capacitively coupled contactless conductivity detector (C4D) etched out from a printed circuit board (PCB) as potential sensor for paper-based analytical systems. Two lines of any desirable pattern forming 35-μm thick planar copper electrodes were produced on a PCB plate (40 mm × 60 mm) by photolithography. The final PCB plate was covered with polypropylene film to serve as the insulating layer for the C4D detector. The film also protected the copper electrodes from corrosion. Electrodes made in this planar geometry make the PCB-C4D suitable as sensor for flat devices such as paper-based analytical devices. For this work, plain paper strips were employed as sample reservoir and as fluidic channel without hydrophobic pattern. A dried paper strip was first placed over the sensor, followed by dispensing a fixed volume of the liquid sample onto the paper. Entrapment of the liquid sample in the paper strip leads to reproducible size and position of the detection zone of the sample liquid for the capacitive coupling effect. High precision was obtained with %RSD ≤1% (n = 18) for standard solutions of KCl. Soil suspensions could be analyzed without prior filtration by placing a drop onto the paper strip extending away from the detector zone. The paper strip filtered out soil particles at the surface of the paper. Therefore, only soil filtrate moved towards the detection zone by lateral flow. The C4D detection using paper strip showed high tolerance to soil suspension with turbidity up to 6657 NTU, offering direct analysis of soil salinity. Cleaning with moist tissue paper between samples is adequate even for dirty samples such as soil suspension. We also monitored conductivity of acid-base reaction in the microfluidic paper channels, which was later applied to the quantification of bicarbonate in water and in antacid tablet ("Soda Mint Tablet"). Contactless conductivity detector from printed circuit board as a universal detector for paper-based analytical systems. Image 1 • Contactless conductivity detector for entrapped liquid on plain paper. • Easily cleaned with household tissue to remove liquid residues and dirt. • Direct measurement of soil salinity with high tolerance to soil suspension. • Potential detector for paper-based analytical systems. [ABSTRACT FROM AUTHOR]

In order to gain rapeseed(Brassica napus) germplasm suitable for planting in saline alkali land and achieve com ⁃ prehensive utilization of the saline soil, in this study, 6 rapeseed germplasm materials including Westar, G101, G112, bgr5, ZS11, and G135 were selected from 523 rapeseed germplasms tested by paper bed with 1.5% of NaCl. Systematic evaluation encompassed germination rates and various growth parameters of the materials under agar salt stress and potted salt stress, in⁃ cluding hypocotyl and root lengths, as well as fresh weight and physiological indices(SOD, CAT, proline, etc.). The results showed that G135 exhibited superior performance under saline stress conditions on 1/2 MS medium, displaying enhanced ger⁃ mination rates, elongation of hypocotyls and roots, and superior fresh weight compared to other 5 germplasms. The order of the salt-tolerance ability of the 6 germplasms was G135 > Westar > bgr5 > G112 > ZS11 > G101 after comprehensive evalua⁃ tion by membership function. In the pot trials, the growth parameters of G135 were also superior to those of other 5 germ ⁃ plasms under the salt stress, and membership function analysis reiterated G135's preeminence in salt tolerance, surpassing G112, Westar, ZS11, G101, and bgr5. Six germplasms were subjected to 0.8% of NaCl stress at the seedling stage in the pot trial, and the antioxidant enzyme activity and proline content of G135 were higher than those of other treatments. After comprehensive evaluation by membership function, the order of the salt tolerance of 6 germplasms was G135 > G112 > Westar > bgr5 > ZS11 > G101. In conclusion, G135, as a salt-tolerant germplasm, showed stable and highly salt-tolerant ability, and could be used for salt-tolerant breeding for rapeseed and study on molecular mechanism of salt-tolerance. [ABSTRACT FROM AUTHOR]

This paper aimed to test the response of household savings to anticipated income changes. Using a data matching technique between the Socio-economic Survey (SES) of Thai Agricultural Households and Labor drawn from crop years 2006/2007 and 2007/2008 and the 2006 Survey of the Integrated Management Plan on Saline Soil in the North-eastern Region of Thailand, this paper did natural experiments comprising both natural and non-natural factors as instrumental variables. The results showed that there existed to some extent evidence of excess sensitivity in Thailand. The robustness of the results was confirmed by using three estimators as well as using seven instrumental variables, which were in the form of actual and subjective data. [ABSTRACT FROM AUTHOR]

Soil salinization has seriously affected agricultural production and ecological balance in the Yellow River Delta region. Rapid and accurate monitoring of soil salinity has become an urgent need. Traditional machine learning models tend to fall into local optimal values during the learning process, which reduces their accuracy. This paper introduces Circle map to enhance the crayfish optimization algorithm (COA), which is then integrated with the regularized extreme learning machine (RELM) model, aiming to improve the accuracy of soil salinity content (SSC) inversion in the Yellow River Delta region. We employed Landsat5 TM remote sensing images and measured salinity data to develop spectral indices, such as the band index, salinity index, vegetation index, and comprehensive index, selecting the optimal modeling variable group through Pearson correlation analysis and variable projection importance analysis. The back propagation neural network (BPNN), RELM, and improved crayfish optimization algorithm–regularized extreme learning machine (ICOA-RELM) models were constructed using measured data and selected variable groups for SSC inversion. The results indicate that the ICOA-RELM model enhances the R 2 value by an average of about 0.1 compared to other models, particularly those using groups of variables filtered by variable projection importance analysis as input variables, which showed the best inversion effect (test set R 2 value of 0.75, MAE of 0.198, RMSE of 0.249). The SSC inversion results indicate a higher salinization degree in the coastal regions of the Yellow River Delta and a lower degree in the inland areas, with moderate saline soil and severe saline soil comprising 48.69% of the total area. These results are consistent with the actual sampling results, which verify the practicability of the model. This paper's methods and findings introduce an innovative and practical tool for monitoring and managing salinized soils in the Yellow River Delta, offering significant theoretical and practical benefits. [ABSTRACT FROM AUTHOR]

This paper presents the swelling behaviour of clayey materials under controlled suction imposed both by a Richards chamber and by controlling the relative humidity with concentrated saline solutions. Soil-water characteristic curves (matrix and total) were determined by the filter paper method. The materials under study belong to the Guabirotuba Formation, of Pleistocene age, in the Curitiba Basin in the state of Paraná, southern Brazil. Materials under several stages of suction of 5000-40 000 kPa were subjected to swelling tests in an oedometer press. The results indicated that the greater the suction the higher the swelling pressure. However, when swelling tests were carried out with suction variation controlled by relative humidity, in which the increase in moisture was very slow, the samples showed no swelling. [ABSTRACT FROM AUTHOR]

Salinization is a process of increasing concentrations of salts in soil and water. Soil salinity is the most serious agricultural problem in irrigation agriculture in Tanzania. Severe salinity can cause significantly lower yields, food insecurity, and environmental degradation. If not properly addressed, soil salinization can accelerate and potentially expand to currently unaffected irrigated agricultural land. Despite the efforts made by the government and other stakeholders, rice production in irrigated rice fields in Tanzania is still experiencing low yields. Current rice yields are between 2.5 and 4 tons/ha, which is low compared to the average rice yields reported in other countries. Salinity problems are caused by the prevailing climate characterized by high evapotranspiration, geological and geographical characteristics of the area, quality of irrigation water, and inadequate land use practices. This paper aims to review available information on the causes and effects of soil salinity on irrigated rice fields in Tanzania and to provide information on management strategies to adjust soil salinity and improve soil fertility. References from books, papers, journals, online readings, and dissertation papers from different universities and institutions were used to get information for this paper review. In this review, the various reasons that cause soil salinity in irrigated fields in Tanzania have been identified, which are the nature of rocks, poor irrigation management, and non-compliance with established irrigation regulations. Also, the effects of soil salinity in Tanzania have resulted in a decrease in yields, an increase in costs of production, poor quality of products, and water shortages for irrigation. Lastly, some recommendations identified to solve the challenges of soil salinity include setting up a local drainage system on affected land, renovating some irrigation facilities, reclaiming the affected soil with gypsum and manure, and flushing all salt-affected water with non-salt water. [ABSTRACT FROM AUTHOR]

Independent lightning rods are often installed in substation grounding systems for lightning protection. The concentrated discharge channel formed when a lightning current flows to the ground through a grounding electrode will cause electromagnetic interference to the directly buried secondary cable. And the three-dimensional structure of the discharge channel will affect the transient electromagnetic field distribution, thereby affecting the electromagnetic transients on cable shields. In order to explore the influence of soil discharge phenomena on the electromagnetic interference of the directly buried secondary cable, in this paper, we carried out experiments on cables in two different grounding modes, single-ended and double-ended grounding, and captured image of soil discharge channels. The results show that the cable grounding mode will affect the coupling mode that causes the shielding layer current. The relative spatial position of the soil discharge channel and the cable has a significant impact on the magnitude of the shielding layer current under both grounding modes. The water content and salt content of the soil also have different degrees of influence on the coupling current of the shielding layer in different grounding modes. [ABSTRACT FROM AUTHOR]

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The measurement of electrical conductivity (EC) has long been a tool for understanding soil properties. Previous studies concluded that EC measurement is not an ion-selective method, but these papers did not address the measurement frequency. An experimental tool and method were developed for semi-factory conditions in a large-scale soil trough at the Institute of Technology of the Hungarian University of Agricultural and Life Sciences. A specially designed and built test apparatus mounted on the tractor's three-point hitch was used as a measuring device. The wear-resistant steel elements of the measuring device were also the sensors for measuring EC. This paper describes the conditions of the measurement series, the measurement results, and our conclusions from the experiments with the soil sensor. Different characteristics were measured in soil moistened with K and Ca solutions at different concentrations. The EC values show an increasing tendency with increasing salt concentration, and we also found that the rate of change of EC is different for different solution ratios. Based on our measurements, we found that the best method to isolate concentration differences is to use the test frequency range 20 Hz–250 kHz. [ABSTRACT FROM AUTHOR]

[Objective] Soil conditioners are commonly used to improve quality and productivity of saline soils. This paper experimentally compares the effects of different soil conditioners on the physical and chemical properties of saline soils. [Method] The experiment was conducted in pots to simulate a rice-oilseed rape rotational cropping system. The soil was amended with calcium superphosphate at rates of 750 kg/hm² (G1) and 1 500 kg/hm² (G2); hydrolyzed poly (maleic anhydride) at rates of 900 kg/hm² (J1), 1 200 kg/hm² (J2) and 1 500 kg/hm² (J3); and Bacillus megaterium at rates of 40 kg/hm² (W1), 60 kg/hm² (W2), and 80 kg/hm² (W3). The control treatment (CK) was conventional fertilization without soil amendment. In each treatment, we measured physical soil properties and electrical conductivity of soil solution. [Result] Compared to CK, J2 increased soil total porosity, maximum water holding capacity, field water holding capacity, and capillary water holding capacity by 12.49%, 13.60%, 13.63% and 12.41%, respectively, while reducing electrical conductivity of the soil solution by 64.73%. W2 improved total soil porosity, maximum water holding capacity, field water holding capacity, and capillary water holding capacity by 8.59%, 9.57%, 9.01%, and 9.79%, respectively, while reducing electrical conductivity of the soil solution by 55.66%. W1 reduced soil bulk density by 4.20%, enhanced maximum water holding capacity, field water holding capacity, capillary water holding capacity and soil organic matter by 6.58%, 9.02%, 9.69% and 25.82%, respectively, while reducing electrical conductivity of soil solution by 8.97%. [Conclusion] Principal component analysis ranked the conditioners and their application rates in terms of their efficacy the following order: 1 200 kg/hm² of hydrolyzed poly (maleic anhydride) > 60 kg/hm² of Bacillus megaterium > 40 kg/hm² of Bacillus megaterium. These findings provide a guidance for practical application of soil amendment agents to improve properties and productivity of saline soils in the studied regions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming to address the problems of poor separation of peanuts and soil and severe damage of pods during peanut harvesting in saline soil, a peanut digging and harvesting machine was designed using extrusion shaking vibration and roller extrusion. Theoretical calculations determined the structural parameters of critical components. The law of motion of the seedling soil assemblage at the stage of separation and transportation was derived by analyzing the kinematic properties. The soil extrusion vibration crushing dispersion and sieving process was analyzed, and the factors affecting soil crushing and separation were determined by establishing the extrusion collision model. One-way and orthogonal tests used soil content, breakage, and loss rates as test indicators. The orthogonal test showed that the working parameters were as follows: working speed was 0.889 m/s, the inclination angle was 21.5°, the working line speed of the sieve surface was 2.00 m/s and the roller gap of the roller squeezing device was 37 mm, the peanut harvesting rate of soil content was 1.36%, the breakage rate was 0.78%, and the loss rate was 1.15%. The paper references developing a peanut harvester for clay-heavy soil with soil separation performance improvement. [ABSTRACT FROM AUTHOR]

Irrigation water with high sodicity risk can lead to soil dispersion, poor drainage, and groundwater contamination. The sodium adsorption ratio (SAR) of soil water is influenced by water loss through evaporation. Evaporation concentrates sodium (Na) and magnesium (Mg), and its impact on soluble calcium (Ca) and alkalinity is more intricate. This study presented a refined sodicity hazard assessment that quantifies the influence of evaporative water loss and calcite precipitation on drainage water. Specifically, the initial equivalent concentration of alkalinity and Ca predominantly determines the potential sodicity risk of drainage water. The alternative approach projects two pathways for potential drainage water SAR , which include limiting the sodium adsorption ratio (LSAR) to represent the upper limit boundary and evaporated-based sodium adsorption ratio (ESAR) to represent the lower limit boundary. When irrigation water alkalinity exceeds the soluble Ca concentration, soluble Ca in the drainage water is limited as calcite precipitates and the drainage water is dominated by Na and Mg. The SAR approaches an upper limit (LSAR) determined by the initial relative concentration of Na and Mg. Conversely, if irrigation water alkalinity is less than the soluble Ca concentration, minimal calcite precipitation occurs, and drainage water is dominated by Na, Mg, and Ca. Then, the SAR approaches a lower limit (ESAR) determined by the initial Ca, Mg, and Na concentrations. To validate the accuracy of this new sodicity risk assessment method, this paper analyzed data extracted from previously published lysimeter studies. Water composition boundaries for each source water were plotted, and these boundaries were compared to the recorded drainage water composition in the lysimeter studies. As salinity increased through evaporation, the drainage water followed a distinct salinization path but remained within the LSAR and ESAR boundaries. This information is essential for irrigation managers to quickly assess water sodicity levels and make timely management decisions. Practical Applications: The application of irrigation water with high sodicity risk can lead to soil dispersion. Therefore, an accurate and straightforward approach to assess the sodicity level of the source water is crucial for irrigation management. The practical implementation of the proposed approach for evaluating the sodium (Na) hazard of an irrigation water source begins with source water analysis, considering soluble Na, calcium (Ca), magnesium (Mg), alkalinity, and electrical conductivity (EC). The irrigation water source is then categorized based on its Ca to alkalinity ratio: an alkalinity-rich water source is where the ratio of Alkdw−/Cadw2+≥1 , and an alkalinity-poor water source is where Alkdw−/Cadw2+<1. As soil water salinity or EC increases through evaporation, the alkalinity-rich water is likely to approach the upper boundary, which is the limiting sodium adsorption ratio (LSAR)=Fc·Na+/Mg2+/2 , and Fc=ECdw/ECiw=1/LF , where ECdw represents the EC of irrigation water, ECiw represents the EC of drainage water, and the leaching fraction (LF) represents the leaching fraction. On the other hand, alkalinity-poor water is likely to remain close to the lower boundary, which is the evaporation-adjusted sodium adsorption ratio (ESAR)=Fc×Na+/(Mg2++Ca2+)/2. This information can help managers determine the suitability of a water source or make sodicity management decisions if poor quality irrigation water is used. [ABSTRACT FROM AUTHOR]

Remote sensing data are an important source of information for monitoring and mapping vegetation cover. Machine-learning methods are a modern and powerful tool for data processing. However, machine-learning methods combined with remote sensing data have hardly been used for soil salinity assessment and mapping in the southern steppe zone of Russia. This paper examines the possibility of applying different spectral characteristics to map soil salinization in solonetzic complexes in the southern steppe zone of Russia (Republic of Kalmykia) using machine-learning methods. A number of predictors were considered, including reflectance coefficients in blue, green, red, and infrared spectral zones; vegetation indices (NDVI, NDVIt, TVI, SAVI, MSAVI, EVI1–EVI4); salinity indices (SI1–SI6); intensity indices (Int1, Int2); brightness index (BI); and an index proposed by the authors. High-resolution images from the QuickBird (2.4 m) and SuperView-1 (2 m) satellites were used. Soil salinity was assessed using two indicators: specific electrical conductivity in water suspension (EC1:5) and sodium activity (aNa1 : 5). Two different machine-learning models were applied in the study: linear regression and neural networks. According to the results obtained, the linear regression model for EC1 : 5 in 0- to 30-, 0- to 50-, and 0- to 100-cm layers has coefficients of determination (R2) of 0.53, 0.59, and 0.79 on the training sample; the test sample managed to obtain coefficients of determination of 0.49, 0.58, and 0.70, respectively. The neural-network model has significantly higher coefficients of determination: R2 for EC1 : 5 in 0- to 30-, 0- to 50-, and 0- to 100-cm layers on the training sample is equal to 0.68, 0.91, and 0.97, and on the test sample, 0.87, 0.86, and 0.88, respectively. This fact indicates a greater potential of this model for cartographic modeling of soil salinity. The best predictors were the following indices: NDVIt, TVI, EVI1, and Int1. The study has shown the potential of using the neural-network model and spectral indices obtained with SuperView-1 images for soil salinity mapping of solonetzic complexes in the south of the steppe zone of Russia. [ABSTRACT FROM AUTHOR]

Soil salinity management can be complex, expensive and time demanding, especially in arid and semi-arid regions. Besides taking no action, possible management strategies include amelioration and adaptation measures. Here we use the World Overview of Conservation Approaches and Technologies (WOCAT) framework for the systematic analysis and evaluation of soil salinisation amelioration technologies in close collaboration with stakeholders. The participatory approach is applied in the RECARE Project Case Study of Timpaki, a semi-arid region in south-central Crete (Greece) where the main land use is horticulture in greenhouses irrigated by groundwater. Excessive groundwater abstractions have resulted in a drop of the groundwater level in the coastal part of the aquifer, thus leading to seawater intrusion and in turn to soil salinisation. The documented technologies are evaluated for their impacts on ecosystem services, cost and input requirements using a participatory approach and field evaluations. Results show that technologies which promote maintaining existing crop types while enhancing productivity and decreasing soil salinity are preferred by the stakeholders. The evaluation concludes that rain water harvesting is the optimal solution for direct soil salinity mitigation, whereas green manuring and the use of biological agents can support increasing production/efficiency and improving soil properties. [ABSTRACT FROM AUTHOR]

The properties of a large number of concrete infrastructures in China are deteriorating year by year, raising the need for repairing and strengthening these infrastructures. By introducing waterborne polymers into a cement concrete system, brittle cracks and easy bonding performance defects of concrete can be compensated for to form a long-life, semi rigid, waterborne polymer-modified cementitious repair material with a promising development prospect. This paper investigates the modification effect of polymer emulsions on ordinary cement mortar. Our research mainly focused on the physical and mechanical properties, durability, microstructure and application status of waterborne polymer-modified cementitious composites. Literature studies show that with the increase in waterborne polymer content (0 wt%~20 wt%), the performance of cement mortar significantly improves, which in turn expands its application range. Compared with ordinary cement mortar, the introduction of waterborne polymers blocks some of the pores in the cement to a certain extent, thus improving its permeability, freeze–thaw resistance and durability. Finally, this paper describes the application of waterborne polymer–cementitious composites in western saline soil environments, as well as discusses the prospects of their development. [ABSTRACT FROM AUTHOR]

Saline soil is composed of abundant soluble salts, exhibiting undesirable properties when used in backfill projects. To address the mentioned problem, a hydrophobic polymer with an active ingredient of hydrosiloxane-containing siloxane was evaluated as a soil additive in this paper. Five groups of specimens were solidified with a fixed dosage of polymer, with initial water contents (IWCs) ranging from 12.8% to 20.8%, to determine the effectiveness of polymer treatment and the effect of IWC. Natural specimens were also prepared to serve as a control condition. Results showed that the polymer formed a hydrophobic interface on the surface of soil particles, causing the shrinkage of the diffuse double layer (DDL) and the flocculation of clay particles. Therefore, the plasticity index reduced, and the fine particles transformed into coarser particles after polymer treatment. Furthermore, the polymer-solidified soil exhibited a significant enhancement in unconfined compressive strength, characterized by an agglomerated microstructure that possessed a high cementing ability. Nevertheless, increasing IWCs continuously induced a decrease in the strength of the solidified soil, especially when the IWC was greater than the optimum water content. The maximum strength increase rate could be up to 98.2%. However, at an IWC of 20.8%, the strength increase rate could still reach approximately 72%. Correlation analysis showed that the solidification mechanism of the hydrophobic polymer was mainly electrostatic interactions. Variable water contents mainly affected the formation of polymer bonding and thickness of DDL. The utilization of hydrophobic polymer for soil improvement in backfill projects shows great potential in light of these findings. [ABSTRACT FROM AUTHOR]

Oil sands mining in northeastern Alberta, Canada, generates tailings containing sand, silt, clay, water, and residual bitumen with hydrocarbons. The impact of tailings on revegetation is a major environmental concern and poses a significant land reclamation challenge. Oil sands companies have recently developed technologies that use thickeners in combination with carbon dioxide to produce non‐segregating tailings (NST), to accelerate the consolidation of tailings while sequestering greenhouse gases. Effects of these tailings on plant re‐establishment have yet to be determined. We investigated the impact of NST on biomass and physiology of 20 boreal woody plant species grown in environmentally controlled growth rooms. The seedlings were grown for 8 weeks in NST capped with boreal forest topsoil or peat‐mineral soil mix or petroleum coke in 50‐cm‐long polyvinyl chloride pipes. We found that the biomass of balsam fir, beaked hazelnut, blueberry, green alder, Labrador tea, lowbush cranberry, paper birch, and raspberry was severely reduced by NST, while the effects on balsam poplar, Bebb's willow, chokecherry, dogwood, saskatoon, and white spruce were relatively weak. This was also the case for jack pine, which showed poor survival in NST. The negative impact of NST on plants can be largely explained by elevated sodium and decreased foliar nutrient concentrations. The impact of NST capping with petroleum coke on plant growth was non‐significant. Differences among species in their survival and biomass responses to NST appeared to be partly a reflection of their natural habitats. Findings from this study can help guide revegetation oil sands reclamation strategies. [ABSTRACT FROM AUTHOR]

The soil–water characteristic curve (SWCC) describes the relationship between water content and soil suction, which is an important tool for determining the engineering properties of unsaturated soil. By measuring SWCC through vapor equilibrium technique, which could obtain soil suction up to 309 MPa, this paper explored the influences of the soil type and salt content on SWCC of saline soil. The experimental results illustrate that fine‐grained saline soil had a good water‐holding capacity, which had a higher air entry value and slower dehydrate rate. The study also brings out the observation that salt had negligible influence on soil suction and parameters effecting SWCC in low suction range; however, this effects was slight until it disappeared with the suction increasing. [ABSTRACT FROM AUTHOR]

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The sustainability of agricultural production on the soils in the Sudano-Sahelian agroecological zone needs current information on the salinity status for appropriate management practices. This paper assessed the effects of soil salinity on the sustainability of crop production in Gusau, Local Government Area, Zamfara State. Soils were sampled from a polygon layer of grid stratification map of Gusau LGA at 0 - 20cm depth, a total of 8 polygon layers with over 50% proportion were selected for the collection of samples. Three soil samples were collected purposively at three different locations to produce eight composite soil samples. Soil parameters that were analyzed include Electrical Conductivity (EC) and Total Dissolved Solids (TDS) which are crucial in determining salinity level. Classification chart was used to classify the soils based on various degree of salinity. The results of the soil samples were interpolated using Inverse Distant Weight (IDW) to create maps of the spatial distribution of salinity level across the study area. Modis 13Q1 NDVI data of the study area from 2000 to 2020 were acquired from LP DAAC. The Area of Interest (AOI) and data attributes were selected. The data was used to show the vegetation responsive changes from salinity, which serves as an indirect method of detecting salinity. The EC values shows non salinity (0 to 2 dS/m), low salinity (2 to 4 dS/m) and mild salinity (4 to 5.7 dS/m). TDS ranged from non-hazard (140 ppm) to high hazard (465 ppm). Nonhazard class ranged (< 150 ppm), low hazard (150 to 250 ppm), medium hazard TDS (250 to 300 ppm) and high hazard (300 to 500 ppm) were found spatially distributed in different parts of the study area. A sustainability map of the study area from the severity of soil salinity which determined different management practices shows three sustainability classes of soils, very sustainable soils, sustainable soils and less sustainable soil. The study concludes that soils in Gusau ranges from moderate salinity towards the North and Central part of the study area and low in the Southern part. By implication, the soils in the North and Central areas can only sustain crops that are not sensitive to salinity. It is recommended that farmers should review their farm management strategies on soils with risk of salinity in order to reduce the rate and implications in the area. [ABSTRACT FROM AUTHOR]

In saline soil areas, the concrete piers of concrete bridges experience long-term corrosion, mainly caused by chloride salts due to alternating temperature changes. Waterborne concrete coatings are prone to failure in this aggressive salt environment. Implementing coating protection measures can improve the durability of concrete and enhance the service life of bridges. However, the effectiveness and longevity of coatings need further research. In this paper, three types of waterborne concrete anti-corrosion coatings were applied to analyze the macro and micro surface morphology under wet–dry cycles and long-term immersion conditions. Various indicators such as glossiness, color difference, and adhesion of the coatings were tested during different cyclic periods. The chloride ion distribution characteristics of the buried concrete coatings in saline soil, the macro morphology analysis of chloride ion distribution regions, and the micro morphology changes of the coatings under different corrosion times were also investigated. The results showed that waterborne epoxy coatings (ES), waterborne fluorocarbon coatings (FS), and waterborne acrylic coatings (AS) all gradually failed under long-term salt exposure, with increasing coating porosity, loss of internal fillers, and delamination. The chloride ion content inside the concrete decreased with increasing depth at the same corrosion time, while the chloride ion content at the same depth increased with time. The chloride ion distribution boundary in the cross-section of concrete with coating protection was not significant, while the chloride ion distribution boundary in the cross-section of untreated concrete gradually contracted towards the concrete core with increasing corrosion time. During the corrosion process in saline soil, the coatings underwent three stages: adherence of small saline soil particles, continuous increase in adhered material area, and multiple layers of uneven coverage by saline soil. The failure process of the coatings still required erosive ions to infiltrate the surface through micropores. The predicted lifespans of FS, ES, and AS coatings, obtained through weighted methods, were 2.45 years, 2.48 years, and 2.74 years, respectively, which were close to the actual lifespans observed in salt environments. The developed formulas effectively reflect the corrosion patterns of different resin-based coatings under salt exposure, providing a basis for accurately assessing the corrosion behavior and protective effectiveness of concrete under actual environmental factors. [ABSTRACT FROM AUTHOR]

The accurate and extensive monitoring of soil salinization is essential for sustainable agricultural development. It is difficult for single remote sensing data (satellite, unmanned aerial vehicle) to simultaneously meet the requirements of wide-scale and high-precision soil salinity monitoring. Therefore, this paper adopts the upscaling method to upscale the unmanned aerial vehicle (UAV) data to the same pixel size as the satellite data. Based on the optimally upscaled UAV data, the satellite model was corrected using the numerical regression fitting method to improve the inversion accuracy of the satellite model. The results showed that the accuracy of the original UAV soil salinity inversion model (R2 = 0.893, RMSE = 1.448) was higher than that of the original satellite model (R2 = 0.630, RMSE = 2.255). The satellite inversion model corrected with UAV data had an accuracy of R2 = 0.787, RMSE = 2.043, and R2 improved by 0.157. The effect of satellite inversion correction was verified using a UAV inversion salt distribution map, and it was found that the same rate of salt distribution was improved from 75.771% before correction to 90.774% after correction. Therefore, the use of UAV fusion correction of satellite data can realize the requirements from a small range of UAV to a large range of satellite data and from low precision before correction to high precision after correction. It provides an effective technical reference for the precise monitoring of soil salinity and the sustainable development of large-scale agriculture. [ABSTRACT FROM AUTHOR]

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Soil salinity assessment methods based on remote sensing data are a common topic of scientific research. However, the developed methods, as a rule, estimate relatively small areas of the land surface at certain moments of the season, tied to the timing of ground surveys. Considerable variability of weather conditions and the state of the earth surface makes it difficult to assess the salinity level with the help of remote sensing data and to verify it within a year. At the same time, the assessment of salinity on the basis of multiyear data allows reducing the level of seasonal fluctuations to a considerable extent and revealing the statistically stable characteristics of cultivated areas of land surface. Such an approach allows, in our opinion, the processes of mapping the salinity of large areas of cultivated lands to be automated considerably. The authors propose an approach to assess the salinization of cultivated and non-cultivated soils of arid zones on the basis of long-term averaged values of vegetation indices and salinity indices. This approach allows revealing the consistent relationships between the characteristics of spectral indices and salinization parameters. Based on this approach, this paper presents a mapping method including the use of multiyear data and machine learning algorithms to classify soil salinity levels in one of the regions of South Kazakhstan. Verification of the method was carried out by comparing the obtained salinity assessment with the expert data and the results of laboratory tests of soil samples. The percentage of "gross" errors of the method, in other words, errors when the predicted salinity class differs by more than one position compared to the actual one, is 22–28% (accuracy is 0.78–0.72). The obtained results allow recommending the developed method for the assessment of long-term trends of secondary salinization of irrigated arable land in arid areas. [ABSTRACT FROM AUTHOR]

Copyright of Zagazig Journal of Agricultural Research is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This document is an editorial that discusses the importance of water in agriculture, particularly in arid and semiarid regions, and the impact of irrigation on hydrological processes. It covers various research fields within agricultural hydrology, such as water-heat-salt-nutrients transport and evapotranspiration modeling, as well as remote sensing applications. The document provides an overview of published papers on this topic, highlighting research gaps and challenges in integrated agro-hydrological modeling, water resource management, non-point source pollution control, soil salinization, data-driven algorithms, and the use of remote sensing technology. It also lists research topics related to hydrology, including remote sensing, sustainability, ecohydrology, crop water requirement, drought assessment, and groundwater, with studies conducted in different regions such as China, South Africa, Pakistan, Sri Lanka, Brazil, and the USA. The document includes a list of research articles covering various subjects, such as the impacts of climate change on streamflow, water footprint of the animal breeding industry, reference evapotranspiration estimation methods, and the effects of controlled tile drainage on crop growth. The articles are authored by researchers from different countries, including China, Spain, the USA, and Sri Lanka. The document also provides information on the authors' contributions, data availability, and conflicts of interest. [Extracted from the article]

Precise prediction of soil salinity using visible, and near-infrared (vis-NIR) spectroscopy is crucial for ensuring food security and effective environmental management. This paper focuses on the precise prediction of soil salinity utilizing visible and near-infrared (vis-NIR) spectroscopy, a critical factor for food security and effective environmental management. The objective is to utilize vis-NIR spectra alongside a multiple regression model (MLR) and a random forest (RF) modeling approach to predict soil salinity across various land use types, such as farmlands, bare lands, and rangelands accurately. To this end, we selected 150 sampling points representatives of these diverse land uses. At each point, we collected soil samples to measure the soil salinity (ECe) and employed a portable spectrometer to capture the spectral reflectance across the full wavelength range of 400 to 2400 nm. The methodology involved using both individual spectral reflectance values and combinations of reflectance values from different wavelengths as input variables for developing the MLR and RF models. The results indicated that the RF model (RMSE = 4.85 dS m-1, R2 = 0.87, and RPD = 3.15), utilizing combined factors as input variables, outperformed others. Furthermore, our analysis across different land uses revealed that models incorporating combined input variables yielded significantly better results, particularly for farmlands and rangelands. This study underscores the potential of combining vis-NIR spectroscopy with advanced modeling techniques to enhance the accuracy of soil salinity predictions, thereby supporting more informed agricultural and environmental management decisions. [ABSTRACT FROM AUTHOR]

Soil salinization seriously restricts the development of agricultural production, the sustainable use of land resources, and the stability of the ecological environment. In order to objectively reveal the research status of soil salinization, CiteSpace software was used to conduct data mining and quantitative analysis on research papers on soil salinization from 2008 to 2023 in China National Knowledge Infrastructure (CNKI) and Web of science databases. The data sources were transformed into visual graphs by reproducing clustering statistics from aspects such as publication volume, authors, keywords, and publishing institutions. In addition, this paper also combined the actual needs and cutting-edge hotspots in relevant research in China, and proposed and analyzed the limitations and future development trends of soil salinity monitoring research in China. This has important practical significance for comprehensively grasping the current research status of salinization, further clarifying and sorting out the research ideas of salinization monitoring, enriching the remote sensing monitoring methods of saline soil, and solving the actual problems of soil salinization in China. [ABSTRACT FROM AUTHOR]