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Understanding soil salinity levels is essential for effective agricultural planning and, consequently, for ensuring food security and sustainability. However, poor practices have significantly impacted soil salinity levels in many developing countries. In Uzbekistan, soil salinity levels have not been adequately assessed and documented over the past decades, leading to adverse effects on agricultural food production. This paper presents a first attempt to systematically document soil salinity levels in the Namangan area of Uzbekistan. Data on soil salinity from the last 22 years (2000-2022) were obtained from the Namangan Regional Department of Agriculture. Additionally, soil samples from the Uychti district of Namangan, collected in 2013, 2014, and 2017, underwent thorough laboratory analysis. Documented soil salinity levels in the Namangan region highlight a need for significant attention to mitigate these impacts. Experimental findings demonstrate the effectiveness of mulching agro-technologies in reducing soil salinity. However, a comprehensive assessment and an adaptive approach to mitigate soil salinity in the Namangan region are urgently needed to ensure long-term agricultural productivity. [ABSTRACT FROM AUTHOR]

Water drives the decay of road subgrades such as frost heave in cold areas and collapse in saline soil areas, which influences the safety and comfort of vehicle transportation. This paper proposes a novel geotechnical material, namely hydrophobized soil, as a subgrade fill material to mitigate water-induced degradation of subgrade. Hydrophobized soil has a low affinity to water and therefore can prevent the subgrade from water infiltration, enhancing the volume stability of subgrades. To demonstrate its feasibility, the hydrophobicity and its durability were investigated in this study. A one-year outdoor weathering test on hydrophobized soil columns was conducted, with the hydrophobicity measured. The results show that hydrophobized sand has different durabilities and exhibits different degradations depending on the chosen hydrophobizing agent and its concentration. Based on the testing results and capillary rise model, the design of hydrophobic hydraulic barrier in subgrade was discussed at the end. [ABSTRACT FROM AUTHOR]

Accurate mastery of the creep characteristics of unsaturated saline soil is extremely important for the long-term stability and safe operation of all types of buildings. In this paper, the research object focused on the saline soil of the Zhangye area, Hexi corridor. The indoor triaxial CU creep test was carried out by means of graded loading to study the creep characteristics of saline soil under different salt content and loading stress. The Merchant and Burgers models were used to predict the creep behavior of the saline soils, and the predicted results were compared with the experimental values. The results showed that the triaxial creep curve of saline soil developed in stage III. Namely, transient creep stage, deceleration creep stage and steady-state creep stage. The creep deformation increases with the increase of salt content and loading stress. The stress–strain isochronous curve has non-linear growth, and the cluster of curves develops from dense to sparse after increasing to long-term strength (100∼150 kPa). The parameters of the Merchant and Burgers model vary with salt content and loading stress, and the creep curve predicted by the Burgers model is closer to the test value. [ABSTRACT FROM AUTHOR]

The ability to accurately obtain soil moisture contents is important in many different fields, including agriculture and branches of civil engineering including hydraulics, transportation, and geotechnical engineering. The moisture content of pavement subgrade affects pavement performance. Long-term monitoring the moisture content of subgrade can allow for better pavement design and maintenance practices. Collecting soil samples for gravimetric testing is time consuming and destructive, which is not practical for long-term monitoring. Soil moisture sensors employing a variety of technologies have been developed for recording soil moisture contents non-destructively and remotely. Soils that are exposed to irrigation or sea waters can have varying amounts of salinity. Salinity in the soil can adversely affect the performance of various sensor technologies. This review paper summarizes the difficulties associated with the use of commonly used, commercially available soil moisture sensors using time domain reflectometry (TDR), capacitance, impedance, time domain transmission (TDT), and transmission line oscillator technology. [ABSTRACT FROM AUTHOR]

Soil salinization and its detrimental agricultural, environmental, and socioeconomic impact over extended regions represent a major global concern that needs to be addressed. The sustainability of agricultural lands and the development of proper mitigation strategies require effective monitoring and mapping of the saline areas of the world. Therefore, robust modeling techniques and efficient sensors that assess and monitor the spatial and temporal variations in soil salinity within an area, promptly and accurately, are essential. The aim of this paper is to provide a comprehensive and up-to-date review of the modeling approaches for the assessment and mapping of saline soils using data collected by the EM38 and EM38MK2 (MK2) sensors at different scales. By examining the current and latest approaches and highlighting the most noteworthy considerations related to their accuracy and reliability, the intention of this review is to elucidate and underline the role of the EM38 and the MK2 type in the recent needs of detecting and interpreting soil salinity. Another aim is to assist researchers and users in selecting the optimal approach for future surveys and making well-informed decisions for the implementation of precise management practices. The study's findings revealed that the integration of the EM38 and MK2 sensors with remote sensing data and advanced methods like machine learning and inversion is a promising approach to the accurate prediction and mapping of the spatiotemporal variations in soil salinity. Therefore, future research focused on validating and expanding such sophisticated modeling applications to regional and global scales should be increased. [ABSTRACT FROM AUTHOR]

Objective Reclaiming the saline coastal soils in eastern China is crucial for ensuring food security. Given the significance of soil carbon in soil quality, this paper investigates the change in soil organic carbon and phosphorus in the soil following initiation of reclamation. Method The experiment was conducted in the northern regions of Hangzhou Bay and Yueqing Bay in eastern Zhejiang province. Soil samples were collected from vegetable fields, orchards, and paddy fields to measure their organic carbon, phosphorus, and other soil properties, from which we analyzed the relationship between soil organic carbon, phosphorus composition, reclamation duration, and land usage. A non-reclaimed soil was taken as the control. Result As reclamation time elapsed, soil pH decreased while total organic carbon (TOC), total phosphorus (TOP), and available phosphorus increased. Fifty years of reclamation led to a reduction in soil pH in Hangzhou Bay and Yueqing Bay by 1.72 to 2.36 and 1.14 to 2.24, respectively. This was accompanied by significant increases in organic carbon and TOP by 126.46% to 294.97% and 130.37% to 266.14%, and available phosphorus by 17.66% to 100.00% and 39.31% to 87.20%, respectively. The decrease in soil pH among different land usages was ranked in the order of wasteland > paddy field > orchard > vegetable field; the increase in soil organic carbon followed the order of paddy field > orchard > vegetable field > wasteland; and the increase in TOP and available phosphorus followed the order of wasteland < paddy field < orchard < vegetable land. Reclamation also significantly increased different forms of soil organic carbon. Over time, the ratio of free particulate organic carbon to organic carbon (fPOC/TOC) in micro-aggregates decreased initially and then gradually increased, while the ratio of occluded particulate organic carbon to organic carbon (oPOC/TOC) increased gradually. The ratio of mineral-associated organic carbon to organic carbon (MOC/TOC) initially increased significantly and then decreased slowly. Land usage had a notable impact on the MOC/TOC ratio, with paddy fields showing the highest influence, followed by orchards and vegetable fields. The impact of land usage on TOP and available phosphorus was more significant than reclamation time. Except for residual phosphorus and HCl-P, other forms of phosphorus increased with reclamation time. It was also found that with the increase in reclamation time, the fraction of residual phosphorus and HCl-P decreased, while the fraction of phosphorus in other forms increased. TOC and organic carbon in different forms exhibited a strong correlation, but no correlation was found between TOP and phosphorus. Conclusion Reclamation of the coastal saline soils results in continuous changes in composition and content of organic carbon and phosphorus, characterized by decreasing pH, increasing organic carbon and phosphorus. Land usage has a more substantial impact on the change in organic carbon and phosphorus than reclamation history. Growing rice promotes organic carbon sequestration, whereas vegetable cultivation enhances phosphorus accumulation. [ABSTRACT FROM AUTHOR]

This paper examines the impact of salinity on the thermophysical properties of soils during artificial freezing. It focuses on analyzing heat and mass transfer in saline soils for constructing a frozen wall around a mineshaft at a potash salt deposit. The presence of salts in the groundwater near the contact point with water-protective strata is common in these deposits. Experimental studies were conducted on clay, chalk, and sand to understand the effect of salinity on the freezing temperature, unfrozen water content, specific heat capacity, and thermal conductivity of wet soil. These findings were used to simulate heat and mass transfer in saline soils using a one-dimensional model. The technique of circumferential averaging was introduced to account for the thermal impact of freeze pipes. The results indicate that higher soil salinity leads to a faster decrease in soil temperature under freezing conditions, although this dependence is weak for clay. This study also revealed that an increase in initial salinity results in a reduction in the thickness of the frozen wall. It was found that, for chalk and sand, there exists a range of initial salinity during which the frozen wall's thickness is almost independent of the initial salinity. [ABSTRACT FROM AUTHOR]

Labor supply adjustment is one of the main mechanisms of farm households, which is often utilized to alleviate the impact of undesired natural circumstances. Nevertheless, how does the farm labor supply respond to the different attributes of natural circumstances, which may be permanent or transitory? This was an interesting research question and needed to be investigated. Therefore, using the matched data from the Socio-economic Survey (SES) of Thai Agricultural Households and Labor, the studies' survey of saline soil, the times series information on regional rainfall in the Northeastern region of Thailand, and the implementation of regression analysis, including the income decomposition technique based on the permanent income hypothesis, the results showed that both permanent and transitory income generated by natural events had a significant effect on the farm labor supply. The farm labor supply had a higher response to transitory income that was determined by rainfall variation compared to permanent income, which was determined by both natural and non-natural factors. There was also evidence that natural permanent income generated by a natural event had a higher impact than non-natural permanent income. Overall, this paper found that natural circumstances could deteriorate the welfare of farm households by forcing them to work harder. Government support should thus be provided both in the short and long run. [ABSTRACT FROM AUTHOR]

Climate change, uneven distribution of water resources and anthropogenic impact have led to salinization and land degradation in the southern regions of Kazakhstan. Identification of saline lands and their mapping is a laborious process associated with a complex of ground measurements. Data from remote sensing are widely used to solve this problem. In this paper, the problem of assessing the salinity of the lands of the South Kazakhstan region using remote sensing data is considered. The aim of the study is to analyze the applicability of machine learning methods to assess the salinity of agricultural lands in southern Kazakhstan based on remote sensing. The authors present a salinity dataset obtained from field studies and containing more than 200 laboratory measurements of soil salinity. Moreover, the authors describe the results of applying several regression reconstruction algorithms (XGBoost, LightGBM, random forest, Support vector machines, Elastic net, etc.), where synthetic aperture radar (SAR) data from the Sentinel-1 satellite and optical data in the form of spectral salinity indices are used as input data. The obtained results show that, in general, these input data can be used to estimate salinity of the wetted arable land. XGBoost regressor ( R 2 = 0.282) showed the best results. Supplementing the radar data with the values of salinity spectral index improves the result significantly ( R 2 = 0.356). For the local datasets, the best result shown by the model is R 2 = 0.473 (SAR) and R 2 = 0.654 (SAR with spectral indexes), respectively. The study also revealed a number of problems that justify the need for a broader range of ground surveys and consideration of multi-year factors affecting soil salinity. Key results of the article: (i) a set of salinity data for different geographical zones of southern Kazakhstan is presented for the first time; (ii) a method is proposed for determining soil salinity on the basis of synthetic aperture radar supplemented with optical data, and this resulted in the improved prediction of the results for the region under consideration; (iii) a comparison of several types of machine learning models was made and it was found that boosted models give, on average, the best prediction result; (iv) a method for optimizing the number of model input parameters using explainable machine learning is proposed; (v) it is shown that the results obtained in this work are in better agreement with ground-based measurements of electrical conductivity than the results of the previously proposed global model. [ABSTRACT FROM AUTHOR]

In this paper, an approach was employed to fabricate a curing agent using multiple solid wastes. To determine the optimal mixing ratio, orthogonal and compaction tests were initially conducted, followed by a comparative analysis of the excitation effects elicited by sodium silicate and NaOH. Remarkably, sodium silicate demonstrated superior suitability as an activator. The final composition was established as follows: 4% sodium silicate, 26% carbide slag, 25% granulated blast furnace (GBF) slag, 35% coal fly ash, and 10% flue gas desulphurization (FGD) gypsum. Under controlled conditions of 20% of curing agent content, the unconfined compressive strength of the solidified soil at 7 d attained 1.54 MPa, thereby satisfying the rigorous construction requirements for highways across all levels. XRD and SEM-EDS analyses revealed that the principal hydration products in the system consisted of ettringite, Friedel's salt, and C-S-H gel. These products enveloped the soil particles, with ettringite and Friedel's salt intermingling and occupying the intricate framework formed by the gel. The synergistic interplay among the components ultimately fostered the development of a coherent soil structure and enhanced overall densification. [ABSTRACT FROM AUTHOR]

The main aim of this paper was to analyze the sensitivity of the five infiltration equations (Kostiakov, Kostiakov–Lewis, Philip, Horton and SCS) and their coefficients to various ponding depths and initial soil moisture under different irrigation managements. The treatments included three qualities of water (electrical conductivity = 6, 3 and 0.6 dS/m), two managements of irrigation (intermittent irrigation and daily irrigation) and three irrigation periods (100, 45 and 8 days). The HYDRUS-1D model was calibrated to simulate infiltration in various initial soil moistures and ponding depths. Evaluating the performance of infiltration equations showed that the Horton and Kostiakov–Lewis had better accuracy and Kostiakov and SCS had less accuracy than the other equations. The empirical coefficients of SCS and Kostiakov had the most and least sensitivities, respectively. Furthermore, Horton was the most sensitive equation, while SCS was the least sensitive one. The output parameters under daily management were the most sensitive to variations in infiltration coefficients, especially when the salinity and sodium contents of water and soil were higher. The results also showed that the effect of the initial soil moisture on the infiltration coefficient in high permeable soil (arising from daily management) was greater; but in low permeable soil (arising from intermittent management), the ponding depth was more effective. It is concluded that the infiltration equations (specifically the SCS equation) and their coefficients (specifically coefficient c) should be calibrated relative to the initial soil moisture, ponding depth, soil solution and water irrigation quality. Particularly in areas with high permeable soil (in the daily management), the calibration of the infiltration equation should be conducted with the initial soil moisture. In these areas, the irrigation period should be controlled. In areas with low permeable soil (in intermittent management), calibration should be carried out relative to the ponding depth. In these areas, the inflow rate should be controlled. [ABSTRACT FROM AUTHOR]

Salvia L. is the largest genus in the family Lamiaceae, with about 1,000 species and a nearly cosmopolitan distribution. Salvia species are used in both traditional and conventional medicines, and other numerous industries, such as spices and perfumes. The number of papers dealing with Salvia exceeds 12,000 and mostly investigates their chemical composition and bioactive properties. A smaller proportion of papers however consider environmental factors, mostly on the effects of microclimate conditions on its geographic distribution along an altitudinal or longitudinal gradient, and very few studies can be found on the effects of emerging stressors on the commercial production of sages of medicinal and economical importance. Here, we summarize available data on the essential oil composition of three economically important sages from the Mediterranean area, that is, Salvia officinalis , Salvia officinalis subsp. lavandulifolia , and Salvia fruticosa , and the effects of climate-related environmental stressors on their chemical profiles. Environmental stress factors, such as an increase in soil salinity and aridity, and changes in annual average temperatures, are going to impose a serious risk on the commercial production of sage essential oils, which are commercially produced in many European countries. This review highlights the already confirmed effects of these stressors on three selected Salvia species and consequently the importance of mitigating the effects of climate change on the commercial production of these essential oils. [ABSTRACT FROM AUTHOR]

By far the most widely used approach in assessing land degradation has been to employ Earth observation (EO) data. For decades now, land degradation has been identified as one of the most pressing problems facing the planet. 10.3390/rs13132483 3 Gedefaw M., Geli H., Abera T. Assessment of rangeland degradation in New Mexico using time series segmentation and residual trend analysis (tss-restrend). [Extracted from the article]

This paper aims at the problem that the fall irrigation quota of drip irrigation farmland under mulch cannot be effectively determined due to the extremely uneven spatial distribution of water and salt and the significant effects of freezing and thawing in the seasonal freeze-thaw area. In response to this problem, based on the field experiment data, this paper uses the joint simulation method of HYDRUS- 2D and SHAW model to simulate the soil water and salt dynamics under different autumn irrigation quotas under the conditions of the Yellow River water irrigation, and studies the single and multi-year autumn irrigation quota of drip irrigation farmland under mulch. The results show that: * When the single year autumn irrigation is conducted, for mildly saline soil, the recommended autumn irrigation quota is 1 100 m³/hm²; for moderately saline soil, the recommended autumn irrigation quota is 2 100 m³/hm²; for heavily saline soil, the recommended autumn irrigation quota is 2 500 m³/hm² when only for the purpose of improving soil quality. * When irrigating in autumn every few years, the non-saline soil should be irrigated in autumn at least once every 3 years. The recommended autumn irrigation quota is 2 000 m³/hm² for irrigation every three years, and the recommended autumn irrigation quota is 1 350 m³/hm² for irrigation every two years. The soil with mild, moderate and severe salinization must be irrigated in autumn every year. [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.)

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.)

Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography 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.)

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.)

This study is carried out between 1994-2023 years in Türkiye. The Gypsophila is a problematic and important genus that needs revision but will take several years. In the article, geographical distributions, endemism, flowering and fruiting months, habitat preffering, phytogeography and IUCN danger category of Gypsophila taxa distributed in Türkiye are explained according to field observations and herbaria records. Belonging to 51 taxa (47 species), almost 980 collections from 400 localities were identified. Other 15 species not carried out by us. The results presented here are based on informations of Gypsophila taxa in the country. In the light of current information, there are a total of 65 taxa belonging to 62 species in the country and these taxa named in actual situation. 39 taxa of these plants are endemics to Türkiye. Almost 40 taxa from 62 species in Türkiye shows natural distribution in Eastern Anatolia region. This situation shows that; 2/3 of Gypsophila taxa is in Eastern Anatolia region and endemic. Irano-Turanian element ratio in the genus is higher than this value. Species of the genus are distributed according to rock, climatic and geographical region. 9 taxa are indicators of gypsum areas. Among the plants in the paper Irano-Turanian elements 36, Saharo-Arabian element 1, Mediterranean elements 7, Euro-Siberian elements 4, Euxine elements 2; Cosmopolitan 1. Endemism; relict endemic 1, local and regional endemics 11, other endemics 20, nonendemics 19 as rare 1 taxon. Distributions to pytogeographical regions of endemic taxa as follows; endemic Irano-Turanian elements 23, endemic Mediterranean elements 6 and endemic Euro-Siberian elements 2. Weeds growing in fields are 4 taxa. There are new interesting geographical distributions for almost 20 taxa. Distributions to life forms of the taxa are Ch: 33, T: 14 and Chz: 4 taxa. Distributions to IUCN Threatened Cathegories of the taxa are Lc: 19, CR: 10, VU: 9, cd: 8, EN: 4, NT: 1. These two factors are dominant in the high level of endemism. 10 taxa in 0-500 m, 21 taxa in 500-1000 m, 26 taxa in 1000-1500 m, 24 taxa in 1500-2000 m, 17 taxa in 2000-2500 m, 7 taxa in 200-3000 m, 1 taxon in 3000-3500 m are naturally growing and vertical distribution. 40 taxa on steppe vegetation and slopes, 18 taxa on rocky (calcer, volcanic and conglomerate rockies) and their crevices, 14 taxa on gibsous rocky places, 10 taxa alpinic pastures/meadows, 4 taxa on macquis vegetation, 4 taxa on sandy soils, 6 taxa on forest (pine and oak) and opens, 16 taxa on fallow fields and margins and roadsides, 5 taxa on saline soils and 5 taxa on stream bads are naturally growing in Türkiye. Flowering months: 2 taxa in April, 17 taxa in May, 38 taxa in June, 40 taxa in July, 23 taxa in August, 1 taxon in September. Fruiting monts: 1 taxon in May, 12 taxa in June, 46 taxa in July, 42 taxa in August, 13 taxa in September, 2 taxa in November. The gene center of this genus has been estimated as the Eastern Anatolian region (Türkiye) in Irano-Turanian phytogeographical region. Five diversity areas in Türkiye identified: Lakes region, Mountaining areas in East Anatolia region, Region of Sivas, Erzincan Malatya, Tunceli, Erzurum, Bayburt, Gümüşhane, Region of Niğde, Aksaray, Ankara, Çankırı, Konya, Çorum, Yozgat, Region of Eskişehir, Kütahya and Bursa are very important areas in diversity for the genus. Existences of G. linearifolia in the country have not become definite. It was seen samples of G. muralis, G. antari, and G. laricina in fields in the country. [ABSTRACT FROM AUTHOR]

Copyright of Revista em Agronegócio e Meio Ambiente is the property of Revista em Agronegocio e Meio Ambiente 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.)

Using indoor soil column simulation test, this paper contrastively studied the effects of different sand covering thicknesses on decades' tillage land soil and idle land soil water and salt distribution and transport law in the same area under brackish water irrigation. In the test, 4 g/L brackish water was used for irrigation, and the sand covering thickness was selected as 3 cm, 6 cm and 9 cm respectively. With pure soil as a reference, the wetting front, cumulative infiltration, water content and electrical conductivity under each treatment condition were recorded and analyzed. The results showed that for two kinds of soil, 3 cm sand covering can not only promote soil water infiltration, but also effectively alleviate the salinization problem caused by the accumulation of salt surface, with good salt leaching effect; For idle land soil, 6 cm sand covering is good in water retention and salt suppression, and different sand covering thickness all have more positive significance to prevent soil salinization caused by brackish water irrigation than for decades' tillage land soil. Therefore, a reasonable sand cover thickness can be selected according to the soil conditions and farming needs to improve the soil planting environment and optimize the use of water resources. [ABSTRACT FROM AUTHOR]

Information on the spatiotemporal variability of soil properties and states within the agricultural landscape is vital to identify management zones supporting precision agriculture (PA). Ground-penetrating radar (GPR) and electromagnetic induction (EMI) techniques have been applied to assess soil properties, states, processes, and their spatiotemporal variability. This paper reviews the fundamental operating principles of GPR and EMI, their applications in soil studies, advantages and disadvantages, and knowledge gaps leading to the identification of the difficulties in integrating these two techniques to complement each other in soil data studies. Compared to the traditional methods, GPR and EMI have advantages, such as the ability to take non-destructive repeated measurements, high resolution, being labor-saving, and having more extensive spatial coverage with geo-referenced data within agricultural landscapes. GPR has been widely used to estimate soil water content (SWC) and water dynamics, while EMI has broader applications such as estimating SWC, soil salinity, bulk density, etc. Additionally, GPR can map soil horizons, the groundwater table, and other anomalies. The prospects of GPR and EMI applications in soil studies need to focus on the potential integration of GPR and EMI to overcome the intrinsic limitations of each technique and enhance their applications to support PA. Future advancements in PA can be strengthened by estimating many soil properties, states, and hydrological processes simultaneously to delineate management zones and calculate optimal inputs in the agricultural landscape. [ABSTRACT FROM AUTHOR]

This paper reports the splitting tensile strength of concrete corroded by saline soil. The wet-dry cycle erosion test and splitting tensile test were performed on concrete cubic specimens with six different erosion inspection periods and a solution with the same concentration as the saline soil. The variation of chlorine and sulfate with erosion depth for different erosion inspection periods of corroded concrete, as well as the powder on the concrete within the erosion depth, were analyzed via X-ray diffraction (XRD). Combined with the parallel bar system, corroded concrete specimens were divided into corrosion and non-corrosion parts. Considering the corrosive effect of saline soil on the concrete specimen, the splitting tensile strength model of the corroded concrete in the saline soil area was established and compared with experimental values. The results show that the calculated values of the splitting tensile strength model established herein agreed with experimental values. The splitting tensile strength of concrete gradually decreased with the increasing erosion depth, and the erosion depth gradually deepened with the increasing wet-dry cycle time. This is because CaCO3, ettringite, gypsum, and Friedel's salts were produced by reacting with concrete in the range of erosion, which resulted in the decrease of splitting tensile strength of concrete. [ABSTRACT FROM AUTHOR]

There are many methods used for soil water content measurement which we can divide into direct gravimetric methods from using soil samples or indirect methods that are based on the measurement of another soil property which is dependent on soil moisture. The paper presents the findings of volumetric water content measurements with gravimetric and time domain reflectometry (TDR) methods. We focused on four variants in the field experiment in Dolná Malanta (Slovakia): control variant (B0+N0), variant with biochar at dose 20 t.ha−1 without N fertilizer (B20+N0), variant with biochar 20 t.ha−1 and N fertilizer 160 kg.ha−1 (B20+N160) and variant with biochar 20 t.ha−1 and N fertilizer 240 kg.ha−1 (B20+N240). TDR is nowadays a well-established dielectric technique to measure volumetric water content; however, its accuracy is influenced by high concentration of salts in soil. In this paper, we evaluated the effect of added N fertilizer on the measuring accuracy of HydroSense II device that is operating under the TDR principle. [ABSTRACT FROM AUTHOR]

One of the most important stress factors affecting agricultural production in the world and in our country is soil salinity. This effect has constantly increased today, causing a decrease in efficiency and quality in many products. The main reason that triggers this situation is unconscious irrigation and evaporation [1]. Under salt stress, ascorbic acid plays an important role in growth regulation and plant metabolism, increasing the accessibility of water and nutrients [2]. Application of non-enzymatic antioxidant molecules such as ascorbic acid is considered an alternative way to reduce the negative effects of salt stress on plants [3]. In this research, it is aimed to determine the effect of ascorbic acid (AsA) application on germination and some physiological parameters of blue skullcap (Scutellaria lateriflora L.) seeds applied with different salt (NaCl) concentrations. This salts and AsA concentrations are taken as 0, 50, 100 and 150 mM. Analytical grade NaCl is used to create salt stress. Before germination, the seeds are subjected to surface sterilization in 5 % sodium hypochlorite solution for 10 minutes [4]. Surface sterilized seeds are kept in AsA solutions of different concentrations for priming for 12 hours [5] and then they are dried on drying papers at room conditions for 24 hours until they return to their previous moisture content. 20 seeds are placed in petri dishes containing double-layer filter paper and soak with 10 ml of solution from each of the different salt concentrations separately. In this research, germination rate (%), germination time (days), root length (cm) and stem length (cm) criteria are examined. As a result of this research, it is determined that increasing salt concentrations have a negative effect on germination. With the application of 100 mM AsA, the highest germination rate is found to be 91 %, germination time is 5.89 days, root length is 1.7 cm and stem length is 2.4 cm. It has been determined that AsA application at optimum level can have a positive effect on the germination of the blue skullcap plant in saline conditions. [ABSTRACT FROM AUTHOR]

Through remote sensing inversion, the evolution and treatment of saline and alkaline land can be monitored on a large scale in real time. The spectral data and salt content of samples for saline and alkaline land are obtained, and the inversion model is an improvement to the extreme learning machine, which is based on the activation function and the seagull optimization algorithm (SOA). First, the paper proposes the two-hidden-layer extreme learning machine (TELM) based on the hyperparameter activation function and the seagull optimization algorithm (HS-TELM). Then, opposition-based learning (OBL), the Cauchy distribution, and the inverse S-shaped functions (Anti-softsign, Anti-tanh, Anti-sigmoid) are used to improve the SOA, resulting in an improved seagull optimization algorithm (ISOA). At the same time, a series of improved algorithms based on the ISOA and the TELM, including the TELM based on the improved seagull optimization algorithm (ISOA-TELM), the TELM with different hidden layers containing different activation functions (D-TELM) based on the improved seagull optimization algorithm (ISOA-D-TELM), the TELM based on the hyperparameter activation function and the improved seagull optimization algorithm (ISOA-HS-TELM), and the TELM with different hidden nodes containing different activation functions (ND-TELM) based on the improved seagull optimization algorithm (ISOA-ND-TELM), are proposed. The experimental results show that the accuracy of the distribution map of salt content is 2.203 g/kg after adding the spectral correction model, which yields the expected high-precision inversion. [ABSTRACT FROM AUTHOR]

The relationship between unfrozen water content and temperature, called as soil freezing characteristic curve (SFCC), is of importance for hydrologic, engineering, environmental issues related to frozen soil. The SFCC of saline soil is essentially a result of phase equilibrium of pore solution, which is similar but not identical to that of bulk solution. However, there is still a vacancy of study on the phase equilibrium of pore solution in frozen soil. In this study, image transformation was used to establish the relationship of phase equilibrium between bulk solution and pore solution, with four introduced parameters. Then, the new model of SFCC for saline soil was proposed based on the equivalent state of bulk solution with Pitzer model and SFCC of nonsaline soil. The model was validated by the experimental data from published articles and showed good performance in calculating SFCC of saline soils regardless of soil type, phase transition path, and soil initial water‐salt condition, and some advantages when compared to other three models. All the four introduced parameters have clear physical meanings and their relationships with soil type and initial salt concentration were discussed. Finally, the evolution of phase diagram from bulk solution to pore solution at icing stage was figured out. Further studies are needed for their relationship at salt crystallization stage. Shifting the research perspective from unfrozen water content to pore solution, this study gives a new approach to research of freezing characteristic of saline soil and could promote hydrological and engineering research in cold regions. Plain Language Summary: The freezing temperature of pure water declines in soil like in solution. There is a reason to believe that the chemical equilibrium of pore solution differs from that of bulk solution. The chemical equilibrium of pore solution, to a certain extent, determines the amount of unfrozen water content, which affects the thermal, hydraulic and mechanical properties of soil. Two phase transition stages have been found in some saline soils with high salt content, which does not appear in nonsaline soils. The relationship of chemical equilibrium between pore solution and bulk solution is the vital interface to apply mature results of chemical characteristics of bulk solution into research of freezing characteristic of saline soils. However, it is still ambiguous for most researchers ignore the soil matrix effect on chemical equilibrium of pore solution. This paper used the transformation of phase diagram from pore solution to bulk solution, sounds like coordinate conversion, to establish their relationship and proposed an intuitive model to calculate the unfrozen water content of saline soil with equivalent state of bulk solution. The performance of the proposed model is good for various saline soils. This study provides an interesting perspective for frozen soil research. Key Points: A soil freezing characteristic curve (SFCC) model for saline soil is proposed with the equivalent bulk solution and SFCC of nonsaline soilGood performance of the new model at predicting SFCC of saline soil both in ice‐eutectic and crystallization‐eutectic pathsThe evolution of phase diagram at icing stage from bulk solution to pore solution is discovered with the proposed model [ABSTRACT FROM AUTHOR]

Due to the impact of climate change and human activities, the problem of soil salinization is increasingly prominent, posing a threat to the safety of the ecological environment and engineering construction. To understand the development tendency of soil salinization, this paper took the saline soil in Western Jilin province as the research object and carried out a long–term investigation into the basic properties of the soil at several monitoring stations. The results showed that the properties of saline soil in Western Jilin province changed regularly at the spatial and temporal scales. In the longitudinal profile, the water content, soluble salt content, and organic matter content in the soil vary greatly with the seasons at a depth range of 0–50 cm, while their changes below 50 cm are not significant. This is related to the influence depth of the external environment. Meanwhile, the content of sand is relatively stable in the depth direction, mostly between 5 and 15%, while the content of silt and clay fluctuates greatly, and there seems to be a mirror relationship between them. Along the N(W)–S(E) direction, the crystallization proportion of clay minerals gradually increases by about 28% because the relatively humid and hot climate is conducive to mineral crystallization. Over time, in the S(E) study area, the precipitation is relatively abundant, and the shallow soil is desalted due to leaching, resulting in high salt storage in the deep soil. However, in the N(W) study area, salt migrates upwards with water under the dominant effects of evaporation and freeze-thaw, leading to the accumulation of salt in shallow soil and a decrease in salt storage in deep soil. In addition, the saline soil in the study area has strong alkalinity, and the pH increases from 8.2 to 9.8 in the N(W)–S(E) direction. Overall, the soil salinization situation in Western Jilin is not optimistic. [ABSTRACT FROM AUTHOR]

Meeting current needs without compromising future generations' ability to meet theirs is the only path toward achieving environmental sustainability. As the most valuable natural resource, soil faces global, regional, and local challenges, from quality degradation to mass losses brought on by salinization. These issues affect agricultural productivity and ecological balance, undermining sustainability and food security. Therefore, timely monitoring and accurate mapping of salinization processes are crucial, especially in semi-arid and arid regions where climate variability impacts have already reached alarming levels. Salt-affected soil mapping has enormous potential thanks to recent progress in remote sensing. This paper comprehensively reviews the potential of remote sensing to assess soil salinization. The review demonstrates that large-scale soil salinity estimation based on remote sensing tools remains a significant challenge, primarily due to data resolution and acquisition costs. Fundamental trade-offs constrain practical remote sensing applications in salinization mapping between data resolution, spatial and temporal coverage, acquisition costs, and high accuracy expectations. This article provides an overview of research work related to soil salinization mapping and monitoring using remote sensing. By synthesizing recent research and highlighting areas where further investigation is needed, this review helps to steer future efforts, provides insight for decision-making on environmental sustainability and soil resource management, and promotes interdisciplinary collaboration. [ABSTRACT FROM AUTHOR]

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Soil salinization is a critical and global environmental problem. Effectively mapping and monitoring the spatial distribution of soil salinity is essential. The main aim of this work was to map soil salinity in Shandong Province located on the Yellow River Delta of China using Sentinel-1/2 remote sensing data and digital elevation model (DEM) data, coupled with soil sampling data, and combined with four regression models: support vector regression (SVR), stepwise multi-regression (SMR), partial least squares regression (PLSR) and random forest regression (RFR). For these purposes, 60 soil samples were collected during the field survey conducted from 9 to 14 October 2019, corresponding to the Sentinel-1/2 and DEM data. Then we established a soil salinity and feature dataset based on the sampled data and the features extracted from Sentinel-1/2 and DEM data. This study adopted the feature importance of the RF model to screen all features. The results showed that the CRSI index made the greatest contribution in retrieving soil salinity in this region. In this paper, 18 sampling points were used to validate and compare the performance of the four models. The results reveal that, compared with the other regression models, the PLSR model has the best performance (R2 = 0.66, and RMSE = 1.30). Finally, the PLSR method was used to predict the spatial distribution of soil salinity in the Yellow River Delta. We concluded that the model can be used effectively for the quantitative estimation of soil salinity and provides a useful tool for ecological construction. [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.)

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.)

This study conducted a nationwide specific assessment of soil chromium (Cr) contamination status in 506 of China's industrial regions. The overall soil Cr concentrations were 0.74–37,967.33 mg/kg, and the soil Cr content in 4.15% of the regions exceeded the reference screening value (2500 mg/kg). Geochemical accumulation index (Igeo) and monomial potential ecological risk index (E) revealed Cr salt production and tanning were the primary control industries. The non-carcinogenic risks posed by Cr salt production and tanning industries were higher than the national average values, and children were the most vulnerable groups. The heavily polluted regions were mainly located at the Yangtze River Delta, the Bohai Rim, the Pearl River Delta, the Yangtze River Basin, and the Yellow River Basin. The Yangtze River Delta was further identified as the high priority control area based on the class distribution of Igeo and E. Regression analysis showed the soil Cr concentrations in industrial regions increased during 2002–2009 and then turned into a declining trend in 2009–2021. This paper gives detailed insights into soil Cr pollution status in industrial regions across China and the results may serve as references for formulating tailored control measures for different industries and areas. [ABSTRACT FROM AUTHOR]

[Objective] Soil salinization is a dynamic process, affected by numerous factors. Understanding its spatiotemporal variation in a region and catchment is important for management. In this paper, we present the soil salinity dynamics and its determinants in Songnen Plain of Heilongjiang province. [Method] The calculation was based on remote sensing imagery of the region acquired from 2000-2020. We used correlation analysis and relative contribution rate analysis to map the spatiotemporal distribution of soil salinity in this region. [Result] On average, areas affected by salt in the region had decreased from 2000 to 2020, at a rate of 2.73 km²/a. But this is mainly due to the reduced soil salinization in some regions, as other regions actually had seen an increase in soil salinization. In particular, soil salinization in Qiqihar had increased because of the increase in cropped lands and GDP. Suihua also saw soil salinity rising due to increased plant areas and population. In contrast, soil salinity in Daqing and Harbin had decreased, due to the increase in surface water resources and decrease in evaporation for Daqing, and the change in cropped land and livestock industry for Harbin. [Conclusion] Change in soil salinization from 2000 to 2020 in Songnen Plain varied, with some areas seeing an increase and others witnessing a decline. In addition to climate change, other reasons underlying such variations in soil salinization include economic development, change in cropping systems and livestock industry. To ameliorate soil salinization and improve land quality, this region should consider improving irrigation and drainage facilities and controlling the groundwater depth not exceeding a critical level. [ABSTRACT FROM AUTHOR]

[Objective] Available water for irrigation in Hetao irrigation district has been reduced consistently over the past decades. Improving its water management to alleviate soil salinity is critical to sustaining crop production in this region. The purpose of this paper is to seek optimal water-saving irrigation schemes for this region by using process-based models. [Method] The semi-distributed hydrological model (SahysMod) is used in our study. We consider spatial variability of numerous factors in the modelling, which include meteorology, hydrogeology, soil, irrigation and crops. The model is then combined with GIS to simulate the spatiotemporal dynamics of soil water and salt under different scenarios. Data measured from 2007 to 2012 and 2013-2016 were used to calibrate and verify the model, respectively. [Result] ①In a business as usual scenario, the annual drainage decreases first before gradually stabilizing, with the average annual drainage being 531 million m³; salinized lands in the middle and upper reaches of the irrigation district decrease slightly, but increase significantly in the lower reach. ②Considering water-saving in the whole irrigation district and ecological demand for water in the downstream and the Wuliangsuhai lake, the total water diversion from the canal head should be reduced by 15% from the current level. This will save up to 646 million m³ of water. ③If the current irrigation amount remains unchanged, the water utilization coefficient of the canal can be improved 17.6% at the best. ④If the reduction in total water diversion from Yellow River is the same, reducing irrigation amount in the field is the best way to boost salt leaching. In this scenario, reducing irrigation amount should be the priority, followed by improving water utilization coefficient of the canal. [Conclusion] In addition to saving water, considering ecological demand of the downstream for water is also important in optimizing water management in Hetao Irrigation District. [ABSTRACT FROM AUTHOR]

[Objective] Alfalfa is sensitive to water stress at branching stage, but how a simultaneous salinity stress affects this sensitivity is not well understood. The objective of this paper is to address this issue. [Method] Pot experiments were conducted in 2018-2019 at the Shengmu High-tech Economic Park, in Dengkou County, Inner Mongolia. It consisted of three water treatments with the soil water content kept at 55%~70% (W1), 75%~85% (W2), and 85%~100% (W3) of the field capacity, respectively. Each water treatment had four salinity stresses with the soil salt content set at 1.0 (S0), 1.5 (S1), 3.0 (S2) and 4.5(S3) g/kg, respectively. In each treatment, we measured osmotic substances, antioxidant enzymatic activities, above- and below-ground biomass at early flowering stage. [Result] Water and salinity stresses reduced water consumption and aboveground biomass more considerably when they worked collectively than working separately. When the water stress was minor, however, imposing a slight salinity stress with soil salt content ≤3 g/kg can increase the contents of proline and Na+, boosted peroxidase (POD) activity, and reduced superoxide dismutase (SOD). This alleviated oxidative damage of the water stress, thereby promoting crop growth. Compared with S0+W1, S2+W1 increased the contents of proline and Na+, and boosted POD activity, by 74.28%, 17.28% and 34.60%, respectively, while reducing SOD activity by 9.87%. These led to an increase in water consumption and aboveground biomass by 6.48% and 2.17%, respectively. [Conclusion] When water stress is not severe, imposing a slight salinity stress can improve the tolerance of alfalfa to water and salinity stress at branching stage. For all treatments we studied, keeping soil salt content in the range of 2~3 g/kg and soil water content in the range of 70%~85% of the field water capacity was optimal to improve resistance of the crop to both salinity and water stresses. [ABSTRACT FROM AUTHOR]

Plastic shed vegetable (PSV) cultivation has become an important vegetable production system in China, which accounts for about 1/4 of the total vegetable production of China. Shandong is the largest facility vegetable growing area in China. Continued years of high-input, high-output planting methods have brought some problems to the surrounding environment. Salinization has not only affected the soil and groundwater environment, but also the growth of vegetables. A comprehensive understanding of soil salinization in plastic shed vegetable fields is important for the sustainable development of the vegetable farming industry. In this paper, random survey sampling was used to collect soil samples from representative PSV production areas in Shandong Province, and the soil salinization status, acidification status, salt ion composition, and the main causes of soil salinity were studied in the survey area. Our study found that the salinized soils (mild, moderate, and severe levels) in the surveyed areas accounted for 40% of the total samples, and the total soluble salt (TSS) increased with the increase of the planting years. After continuous planting for 10 years, the soil pH showed a downward trend, indicating that salinization and acidification occurred simultaneously. A significant positive correlation was observed between TSS and soil organic matter (SOM) (r = 0.4773**). Principal component analysis found that , , , , Ca2+, K+, Mg2+, and Na+ had higher positive loads on principal component 1, the factor loads were 0.557–0.927, and the contribution rate reached 34.928%. Correlation analysis also showed that TSS was positively correlated with the concentrations of these ions (P < 0.01). The soil salinization status should be closely monitored and regulated by regulatory authorities to improve environment and soil health through balanced fertilization, thereby improving the yield and quality of vegetables. [ABSTRACT FROM AUTHOR]

Soil drought and salinity are stresses that seriously restrict plant productivity. Water and salt stress often occur simultaneously or sequentially in the heavily irrigated field in the arid and semi-arid areas. The impacts of drought and salinity on plants range from morphological adaptations to molecular responses. Instead of studying these twin abiotic stresses in isolation, there is a need to understand the interactions between water and salt stresses and the combined influence on plant growth, yield, and survival. Recent studies demonstrated that the responses of plants to twin stresses cannot be directly predicted from simply studying one of the stresses at a time. This paper reviews the effects of single and combined drought and salt stresses on photosynthetic, stomatal, mesophyll, and hydraulic traits of plant leaves and their coordination. Paper also discusses the drought and salt tolerances mechanisms involving morphological adaptation, hydraulic control, hormonal regulation, osmotic adjustment, ion homeostasis, and antioxidant defense. We propose some mitigation and management strategies, including screening tolerant varieties, inducing stress resistance/tolerance, adding bacteria and fungi, and optimizing field management, with an aimaim to improving water use efficiency and yield under combined stress. [ABSTRACT FROM AUTHOR]

The aim of this review paper is to identify the production trends of shrimp and rice farming systems and associated hydrobiological parameters such as salinity in the coastal districts of Bangladesh. An intensive literature review has been conducted to explore salt stress-driven land use change, crop production, and changing ecosystem hydrobiology to adapt climate change impact from 2012–2022. The results indicate that a gradual extension of salt-driven land use and land cover (LULC) change has stressed agricultural production to a greater extent from 1973 to 2022 due to the high level of salinity. The unplanned expansion of shrimp culture is creating adverse consequences for the coastal ecosystem. Some suggestions have been proposed by analysing the mechanisms of crops' response to salt stress, including several physiological, biochemical, and molecular bases to mitigate the adverse effects of salinity on agricultural production. Alternatively, prawn, shrimp, and crab have similar or slightly higher economic outputs, except for the crop-based agricultural system, which is highly affected by salinity rise. However, due to low input costs, low maintenance, and less environmental impact, farmers are shifting towards crab fattening and thus changing the hydrobiology of coastal land use and land cover. [ABSTRACT FROM AUTHOR]