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Tall wheatgrass is cultivated for pasture in marginal areas around the world due to its tolerance to abiotic stress including seasonal droughts and floods, as well as saline and alkaline soils. However, there is concern about its biomass productivity, which often does not exceed that of natural pastures. In this work we hypothesize that tall wheatgrass is a plant more sensitive to low P availability than commonly assumed. A glasshouse sand culture experiment was conducted to analyze morpho-physiological responses of tall wheatgrass to different P availability levels: 1 µmol L−1 phosphorus (severe deficiency, P1), 10 µmol L−1 phosphorus (representative value of soil solution in the region, P10) and 500 µmol L−1 phosphorus (full P supply, P500). Our results show that both limiting P conditions strongly decreased plant development and biomass accumulation, and altered above- and below-ground morphology, in comparison with P500 plants. The latter, in turn, had relative growth rate values comparable to those of other cultivated grasses under non-limiting conditions. In both P-deficient treatments, plant development was severely delayed starting from leaf number 3, even when P concentration in the pseudostem at early stages was similar or even higher than that of P500 plants. Our results suggest that developmental inhibition of tall wheatgrass at low P supply may be the consequence of a specific plant response to P concentration in soil solution, rather than to direct P starvation in plant tissues, and underlines the need of improvement of this species to enhance productivity in this environment. [ABSTRACT FROM AUTHOR]

Agronomy biofortification is an important crop management strategy to enhance concentrations of micronutrients in edible portions. The availability of micronutrients for plant uptake is reduced by the high salinity, pH, and lime of soils. Hence, this study aimed to determine the most appropriate time and the best ratio of zinc (Zn) and iron (Fe) consumption during the wheat growth stages in a saline and calcareous soil. The experiment consisted of two factors with four levels; 0, 30, 60, and 120 kg Zn ha−1 as Zn0, Zn1, Zn2, and Zn3 respectively, and 0, 2.5, 5, and 7.5 kg Fe ha−1 as Fe0, Fe1, Fe2, and Fe3 respectively, in a randomized complete block design with four replications. The results showed that the interaction effects of Fe and Zn fertilizers application were significant on the wheat yield indices and concentration of Fe and Zn in wheat shoots and grain. The simultaneous application of 120 kg Zn ha−1 and 5 kg Fe ha−1 caused significant improvement (p < 0.05) in thousand kernel weight (9.1%) and subsequently grain yield (23.4%) compared to the control treatment. The Zn concentration in the wheat shoot during tillering (37.0–58.2 mg Zn kg−1) was higher than the other two growth stages (elongation (29.2–40.8 mg Zn kg−1) and booting (20.0–31.0 mg Zn kg−1)). While the highest Fe concentration in wheat shoots was observed at the stem elongation stage (98.5–268.8 mg Fe kg−1), then the booting stage (91.0–150.8 mg Fe kg−1) and finally the least absorption was at the tillering (80.0–120.0 mg Fe kg−1). Because of the high calcium carbonate, salinity and Zn- deficient soil of the experimental site, the Zn concentration in wheat grain was obtained in a range of 3 to 19 mg kg−1. The results clarified that the fertilizer application of 30 kg Zn ha−1 and 2.5 kg Fe ha−1 can be proportionally and simultaneously increased the concentration of Fe and Zn in wheat grain by 100%. Therefore, the soil application of 30 kg Zn and 2.5 kg Fe per hectare proposed for improvement in quantitative (619 kg ha−1 increase in wheat grain yield) and qualities (100% increase in grain Zn and Fe concentration and 8% increase in thousand kernel weight) indices of wheat yield in calcareous and saline soils. [ABSTRACT FROM AUTHOR]

Zinc (Zn) deficiency and salt stress are well-known soil problems and often happen parallelly in cultivated soils. In this study, Zn-amino acid complexes (Zn-AAc) were used as a source of Zn to determine their effects on salt-induced damage in wheat plants. The bread wheat (Triticum aestivum L. cvs. Kavir) was supplied with Zn-glycine (Zn-Gly), Zn-alanine (Zn-Ala), and ZnSO4 as Zn sources at three salinity levels (EC 2, 4 and 6 dS m-). Salinity caused a significant decrease in shoot dry matter and grain yield of wheat, but this negative effect was significantly improved by the application of Zn-AAc. Salt stress decreased shoot and grain Zn concentration, but this reduction was lower in plants supplied by Zn-AAc. Calcium (Ca) and potassium (K) concentrations were increased in a shoot by salinity stress while decreased in grain. Sodium (Na) concentration decreased in shoot and grain by using Zn-AAc. At all of the salinity levels, wheat supplied with Zn-AAc had lower lipid peroxidation compared to those grown under the ZnSO4 source. Application of Zn-AAc increased the activities of catalase (CAT) and superoxide dismutase (SOD) in the roots of wheat plants in saline conditions. Based on the results, the adverse effects of salinity stress on wheat plants can moderately improve with Zn-AAc application. [ABSTRACT FROM AUTHOR]

Aim: Estuarine vegetation routinely experiences natural tidal fluctuations and is highly vulnerable to extreme events such as heavy rainfall, leading to changes in plant population structure and adaptability. Genetic and epigenetic modifications are widely considered to be mechanisms of phenotypic variation, triggered in plants responding to extreme changing environments. However, understanding on correlations among genetic, epigenetic, and phenotypic variation of wild plant populations is still limited. Location: China. Methods: In this study, populations of the typical wetland clonal species Phragmites australis were selected from four estuaries along various latitudes in China. Genetic and epigenetic diversity and phenotypic variation of these populations were analysed. Results: Phenotypic variation of P. australis populations was the highest at Yellow River Estuary and the lowest at Min River Estuary. Across all estuaries, Genetic and epigenetic diversity was strongly linear‐correlated. Genetic diversity had significant correlations with variation in reproductive traits, whereas epigenetic diversity had significant correlations with variation in growth traits. Climatic factors of mean annual temperature and precipitation, as well as soil nitrogen and phosphorus, were negatively correlated with variation in genetic diversity, epigenetic diversity, and variation in reproductive traits of P. australis populations along latitudes. Variation in growth traits was negatively correlated with soil salinity, reflecting the limiting effect of salinity on plant growth. Main Conclusion: Our findings found that genetic and epigenetic variations may play different roles in phenotypic variation of P. australis populations along latitudes, the variation becomes greater when the climatic and edaphic conditions deteriorate. The findings shed new light on the adaptation and evolution of wetland plant populations along a large latitudinal scale, and may contribute to the revegetation of estuary wetlands. [ABSTRACT FROM AUTHOR]

The index of Erodible Fraction (EF) component against wind is well known as a criteria of soil wind erodibility. This study was conducted to estimate the index of EF by utilizing support vector machine (SVM), artificial neural network (ANN) and genetic algorithm (GA-ANN) methods. For this reason, 95 soil samples were collected 10 cm above the soil surface of Allahabad plain in Qazvin province. Then the percentage of aggregates with a diameter of less than 0.84 mm, pH, EC, soil saturation capacity, SAR, equivalent calcium carbonate, organic matter, clay, sand and silt were measured and used in SVM, ANN and GA-ANNs model construction and testing. Results revealed that the EF had a significant correlation at the level of 1% with five soil characteristics, including pH, EC, SAR, clay and organic matter. On the other hand, the ANNs model developed for EF prediction had higher accuracy (R2 = 0.49) than the GA-ANNs model (R2 = 0.37) and SVMs model (0.02). All models were approximately overestimated and the GMER values for SVMs, ANNs and GA-ANNs models were 1.11, 1.15 and 1.08, respectively. However, according to the Akaike information criterion (AIC), all of them had similar power model estimation. Although SVMs offer good accuracy and perform fast prediction in this study, it did not perform well. This issue may be related to the complexity of the relationship between EF and soil properties. [ABSTRACT FROM AUTHOR]

Safflower is a climate-resilient, quality oilseed with high resistance to water scarcity, soil salinity, and frost-prone areas, and it has a wide range of applications in daily life, ranging from food to pharmaceutical to industrial. Adapting high-quality oil-content-producing safflower cultivars can help reduce costs and reduce precious foreign exchange in countries like Pakistan. Exotic germplasm imported from the United States Department of Agriculture-Agricultural Research Service (USDA-ARS), consisting of 145 exotic safflower accessions and four local control cultivars were planted under semi-arid conditions in Faisalabad, Pakistan, during winter 2018-19 and 2019-20 season using an augmented design with unreplicated entries and replicated checks. Genotypic coefficient of variability (GCV) analysis revealed significant variation among the accessions of safflower for achene yield plant-1, heads plant-1, and branches plant-1. The Pearson correlation analysis revealed a significant but negative correlation between days to maturity and days to 50% flowering. The results revealed larger achene yields and earlier maturity in safflower planted in early winter. Biplot analysis found that five of the tested accessions had higher achene yield plant-1, while four of the other accessions had a higher percentage of oil than the control, which was the local safflower check-31, which had the highest oil content and best quality traits. Furthermore, the dendrogram revealed that four safflower accessions exhibited higher morphological uniqueness across the investigated traits during both years of study, which can be employed for future varietal development. [ABSTRACT FROM AUTHOR]

With the increasing output of coal fly ash (CFA) and garden waste, it is of great significance for environmental protection and resource utilization to establish if it can be recycled. The saline soil is widely distributed in the coastal areas of northern China, with high salt content and poor physical and chemical properties, which seriously affects the development of local agriculture and forestry and causes the waste of arable land. If CFA and garden waste compost (GWC) can be applied to saline soil improvement, it not only improves the local soil problem, but also helps environmental protection. Leaching salt is an important measure to reduce salt content in saline-alkali soil. The purpose of this study was to explore the effect of CFA and GWC on salt leaching of coastal saline-alkali soil through a soil column simulation test. The use of CFA and GWC promoted leaching and reduced leaching time. The addition of CFA and GWC to the soil suppressed the increase of HCO3- and CO32- during leaching, but increased the salt ion content of the soil after leaching. The addition of CFA to the soil reduced the ion retention of GWC in the soil, but the application of CFA and GWC had no significant effect on the leaching sequence of salt ions. CFA and GWC added to the soil improved the physicochemical properties and the quality of saline soils, but GWC was less effective than CFA in improving soil physicochemical properties. Application of CFA reduced the leaching time of soil salt ions by about 25%, as well as reduced the pH, EC, SAR, and total salt ion content of the soil by 2.18%, 20.83%, 56.63%, and 38.95%, respectively. [ABSTRACT FROM AUTHOR]

Soil salinity is one of the most devastating environmental impediments that poses a significant threat to agricultural practices hamper crop productivity worldwide. In the present study, a total of thirty finger millet genotypes were examined through in vitro screening at varying sodium chloride concentrations (0, 75, 175, 275, and 375 mM). Based on the morphological characteristics, visual salt injury (VSI) and salinity susceptibility index (SSI), two tolerant (TRY–1 and ML–365), two moderately tolerant (GPU—48 and GPU—28) and two susceptible (VL–146 and Indaf–9) genotypes were shortlisted. Further, the greenhouse illustrated the experiment to assess physiological and biochemical response at the seedling stage by imposing sodium chloride concentrations (0 and 375 mM). The results revealed that TRY–1 was on par among all the studied genotypes that exhibited a significant increase (P < 0.05) in phenotypic (germination percentage, shoot length, root length, and seedling vigour index) biochemical characteristics (contents of total chlorophyll, proline, phenolic, and flavonoids) and antioxidant enzyme activities (SOD and CAT) under varying salinity regimes indicating a strong defense mechanism against salinity-induced oxidative and osmotic stress. In contrast, Indaf—9 exhibited a significant decrease in all the growth and physiological traits and an increment in MDA and H2O2 content compared to other genotypes. In Indaf—9, MDA increased by 184% whereas in TRY—1, it increased by 105%. In contrast, proline content was enhanced as maximum in TRY –1 (239%) compared to Indaf—9 (191%) from 0 to 375 mM sodium chloride concentration. Our findings were supported by extensive statistical analyses such as cluster analysis, correlation, and PCA, indicating key contributing traits involved in salinity stress tolerance. Therefore, this study may help select the salt-tolerant genotypes and contribute to sustainable agriculture by increasing food production in saline-prone agroecological zones. [ABSTRACT FROM AUTHOR]

Amorphous silica (a-SiO2), found in rice husk ash, is a valuable material due to its high silica content, large surface area, excellent pozzolanic properties, and strong binding ability with cement. These characteristics make it ideal for use as a supplementary cementitious material and a sustainable alternative for the partial replacement of ordinary Portland cement. This study aims to optimize the recovery process of amorphous silica from rice husks cultivated under various soil conditions (normal, drought, saline, and acidic soils), which are experiencing significant fluctuations due to climate change in many rice-producing countries. Experiments were conducted on rice husks under different pyrolysis conditions at temperatures of 700 ℃, 800 ℃, and 900 ℃, with varying calcination durations. Through comprehensive analysis using Scanning electron microscopy (SEM) and X-ray diffraction (XRD), along with the evaluation of amorphous silica recovery efficiency, we identified the optimal conditions for producing amorphous silica from rice husks. The analysis revealed that the highest recovery efficiency was achieved at a pyrolysis temperature of 700 ℃ for 1 hour. Under these conditions, the recovery efficiencies were 87.9% for normal soil RHA, 96.5% for saline soil RHA, 94.8% for drought soil RHA, and 95.6% for acidic soil RHA. The phase structure, surface morphology, and particle size of the RHA-derived amorphous silica, ground to micrometer sizes, were found to be similar to commercial products such as ordinary Portland cement and silica fume. This study provides a foundation for scaling up the production of amorphous silica from rice husk ash on an industrial scale, considering the relationship between optimal recovery efficiency and the origin of the rice husk ash, thus contributing to the development of environmentally friendly construction materials. [ABSTRACT FROM AUTHOR]

Purpose: Environmental stresses are a main disturbing factor influencing horticultural productivity around the world. It will affect all plants including resistant or non-resistant cultivars. So, it is important to find the better cultivars and to check the response to adverse environmental conditions. Research method: Thus, the present research was conducted to evaluate responses of different bearing status of pistachio cultivars including Kalleh-Ghochi (K), Ohadi (O) and Ahmad-Aghaii (A), grafted on Badami-Rize-Zarand as rootstock, for six consecutive years to soil salinity. Findings: ONbearing trees of 'Ahmad-Aghaii' showed the highest yield, followed by 'Ohadi' and 'Kalleh-Ghochi'. In addition, the lowest leaf temperature was observed with this cultivar. Although the highest nitrogen, sodium, carbohydrate, peroxidase and leaf temperature was obtained in ON-bearing trees, however, the lowest potassium and total phenol content indicated in OFF-bearing status. It was found a negative correlation between leaf potassium content and ABI, between leaf peroxidase activity and ABI and between leaf temperature and ABI. On the other hand, leaf temperature increased as leaf sodium content increased. Research limitations: There was no limitation. Originality/Value: From data presented here, it is concluded that salinity and Na accumulation might be effective in changing the response of the pistachio cultivar under harsh environmental conditions which affects yield component and alternate bearing index. [ABSTRACT FROM AUTHOR]

The Yellow River Delta (YRD) has the world's highest land formation rate. However, soil salinization has caused severe land degradation in the region. Understanding the distribution of soil salinity and its variation is essential for saline soil management. This study combined soil salinity sampling data, remote sensing imagery, and layers of geographic environmental factors. Three different models, including Ordinary Kriging (OK), Geographically Weighted Regression (GWR), and Bayesian Maximum Entropy (BME), were used and compared to predict the soil salinity of two soil layers in 2006 and 2022. Then the spatial distribution characteristics and development trends of soil salinity in the YRD were analyzed. The results indicated that (1) The BME model is an optimal salinity prediction model that integrates soft data from multiple sources to perform nonlinear estimates. Compared to the OK and GWR models, the RMSE was reduced by up to 25% and 13%, respectively, and the greatest improvement in R2 was increased from 0.0534 and 0.2718 to 0.5569, respectively. (2) Soil salinity in the YRD shows a spatially increasing trend from the southwestern inland to the northeastern coast. Over the past 16 years, the salinization pattern has become more complex: soil salinization has been mitigated in the central and southern regions, with the average salinity decreasing from 1.03% to 0.86% and the salinization rate decreasing from 99% to 88%; and it has significantly intensified in the northern part of the study area near the old Yellow River channel and the Gubei Reservoir, and in some scattered inland areas. Continuous water and sediment regulation in the Yellow River basin and ecological management of natural reserves can generally alleviate soil salinization, but the risk of soil salinization can be increased by seawater erosion, inappropriate land use, and resource exploitation. [ABSTRACT FROM AUTHOR]

Under the sufficient nitrogen supply, it is of great significance to investigate the law of biomass allocation, root morphological traits, and the salt absorption capacity of euhalophytes to evaluate their biological desalination in saline soil. Although the curvilinear responses of biomass accumulation and root morphology in response to soil salinity have been recognized, these perceptions are still confined to the descriptions of inter-treatment population changes and lack details on biomass allocation in organs at an individual level. In this study, Suaeda salsa was grown in root boxes across a range of soil salt levels. The study showed that their growth and development were significantly affected by soil soluble salts. The law of biomass allocation was described as follows: increased soil soluble salts significantly increased the leaf mass ratio and decreased the stem mass ratio, and slightly increased the root mass ratio among treatments. For individuals at each treatment, leaf mass ratio > stem mass ratio > root mass ratio, except in the control treatment at the flower bud and fruit stages. Biomass responses of the control treatment indicated that salt was not rigorously required for Suaeda salsa in the presence of an adequate nitrogen supply, as verified by the correlation between biomass, nitrogen, and soil soluble salt. Salt could significantly inhibit the growth of Suaeda salsa (P<0.01), whereas nitrogen could significantly promote its growth (P<0.01). Root morphology in response to soil soluble salts showed that salt acquisition by the root was highest at a salt level of 0.70%, which corresponds to light saline soil. Consequently, we conclude that phytodesalination by Suaeda salsa was optimal in the light saline soil, followed by moderate saline soil. [ABSTRACT FROM AUTHOR]

Soil salinity is a major abiotic stress that limits the growth and productivity of horticultural crops. Most fruit crops are glycophytes, and their production is adversely affected by salt stress. The key findings indicate that salinity reduces several plant growth parameters such as shoot and root length, number of leaves, plant biomass and relative water content as well as biochemical parameters such as photosynthetic pigments and proline. Physiological results show decreased water absorption, nutrient imbalances such as changes in ion concentrations and hormone levels and increased oxidative stress. Several mitigation strategies are recommended, such as the use of salt-tolerant rootstocks, application of growth regulators and soil amendments to enhance salt tolerance in tropical fruit crops. This review concludes that integrating physiological and agronomic strategies is essential for mitigating the adverse effects of salinity on tropical fruits. [ABSTRACT FROM AUTHOR]

Soil salinity is a serious concern for tomato culture, affecting both yield and quality parameters. Although some genes involved in tomato salt tolerance have been identified, their genetic diversity has been rarely studied. In the present study, we assessed salt tolerance‐related traits at juvenile and adult stages in a large core collection and identified salt tolerance quantitative trait loci (QTLs) by genome‐wide association study (GWAS). The results suggested that a major QTL is involved in leaf sodium accumulation at both physiological stages. We were able to identify the underlying candidate gene, coding for a well‐known sodium transporter, called SlHKT1.2. We showed that an eQTL for the expression of this gene in roots colocalized with the above ground sodium content QTL. A polymorphism putatively responsible for its variation was identified in the gene promoter. Finally, to extend the applicability of these results, we carried out the same analysis on a test‐cross panel composed of the core collection crossed with a distant line. The results indicated that the identified QTL retained its functional impact even in a hybrid genetic context: this paves the way for its use in breeding programs aimed at improving salinity tolerance in tomato cultivars. [ABSTRACT FROM AUTHOR]

AbstractThe study investigates the drying behavior and desalination effectiveness of porous ceramic tiles made from fired clay materials like bricks or pottery on soil columns initially saturated with saline solution. Evaporation kinetics experiments compared the drying of saline soil with and without a ceramic tile. For soil without a ceramic cover, salt precipitation formed an efflorescent crust that initially (t ∼ 30 h) reduced the evaporation rate. However, with continued drying, the tensile stress caused cracks in the crust, allowing increased evaporation through the cracks (t > 200 h). When covered with a ceramic poultice, the saline solution was wicked into the porous ceramic by capillary action. Rapid salt efflorescence was observed on the ceramic surface. The ceramic layer initially reduced the soil evaporation rate due to pore clogging caused by salt precipitation. The pore structure characteristics of the ceramics significantly impacted their desalination performance. After an initial fast drying period controlled by evaporation, a reduced drying rate was observed as salt clogging effects became dominant, especially for the low porosity ceramic (t ∼20 h). The porous ceramic poultices could effectively extract salts from the soil, but their desalination efficiency depended critically on their pore structure properties. An industrial-based clay ceramic with large and more connected pores (porosity 0.33) was found to be around 62% more efficient in removing NaCl than a handmade pottery with small pores (porosity 0.18). [ABSTRACT FROM AUTHOR]

This study aimed to investigate the biodegradation behaviour of starch/nanocellulose/black tea extract (SNBTE) films in a 30-day soil burial test. The SNBTE films were prepared by mixing commercial starch, nanocellulose (2, 4, and 6%), and an aqueous solution of black tea extract by a simple mixing and casting process. The chemical and morphological properties of the SNBTE films before and after biodegradation were characterized using the following analytical techniques such as field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), and fourier transform infrared (FTIR). The changes in soil composition, namely pH, electrical conductivity (EC), moisture content, water holding capacity (WHC), soil respiration, total nitrogen, weight mean diameter (MDW), and geometric mean diameter (GMD), as a result of the biodegradation process, were also estimated. The results showed that the films exhibited considerable biodegradability (35–67%) within 30 days while increasing soil nutrients. The addition of black tea extract reduced the biodegradation rate due to its polyphenol content, which likely resulted in a reduction in microbial activity. The addition of nanocellulose (2–6% weight of starch) increased the tensile strength, but decreased the elongation at break of the films. These results suggest that starch nanocellulose and SNBTE films are not only biodegradable under soil conditions but also positively contribute to soil health, highlighting their potential as an environmentally friendly alternative to traditional plastic films in the packaging industry. [ABSTRACT FROM AUTHOR]

Water scarcity and droughts are among the most challenging issues worldwide, particularly in arid and semi-arid regions like Saudi Arabia. Date palm (Phoenix dactylifera L.), a major crop in Saudi Arabia, is being significantly affected by water scarcity, soil salinity, and desertification. Alternative water sources are needed to conserve freshwater resources and increase date palm production in Saudi Arabia. On the other hand, Saudi Arabia has a significant number of aquaculture farms that generate substantial amounts of wastewater, which can be utilized as an alternative source of irrigation. Therefore, this study aimed to assess the potential of aquaculture wastewater as an alternative irrigation source for date palm orchards. Aquaculture wastewater was collected from 12 different farms (Al-Kharj, Al-Muzahmiya, and Al-Qassim regions, Saudi Arabia) and its quality was analyzed. The impacts of aquaculture wastewater irrigation on soil quality, nutrient availability, nutrient status of date palm trees, and dates fruit quality were assessed in comparison to source water (freshwater) irrigation at Al-Kharj, Al-Muzahmiya, and Al-Qassim regions. The water quality analyses showed higher salinity (EC = 3.31 dSm−1) in farm Q3, while all other farms demonstrated no salinity, sodicity, or alkalinity hazards. Moreover, the aquaculture wastewater irrigation increased soil available P, K, NO3−–N, and NH4+–N by 49.31%, 21.11%, 33.62%, and 52.31%, respectively, compared to source water irrigation. On average, date palm fruit weight, length, and moisture contents increased by 26%, 23%, and 43% under aquaculture wastewater irrigation compared to source water irrigation. Further, P, K, Fe, Cu, and Zn contents in date palm leaf were increased by 19.35%, 34.17%, 37.36%, 38.24%, and 45.29%, respectively, under aquaculture wastewater irrigation compared to source water irrigation. Overall, aquaculture wastewater irrigation significantly enhanced date palm plant growth, date palm fruit quality, and soil available nutrients compared to freshwater irrigation. It was concluded that aquaculture wastewater can be used as an effective irrigation source for date palm farms as it enhances soil nutrient availability, date palm growth, and date fruit yield and quality. The findings of this study suggest that aquaculture wastewater could be a viable alternative for conserving freshwater resources and increase date palm production in Saudi Arabia. [ABSTRACT FROM AUTHOR]

Soil microorganisms play a crucial role in the plant invasion process, acting as both drivers of and responders to plant invasion. However, the effects of plant invasion on the complexity and stability of co-occurrence networks of soil microbial communities remain unclear. Here, we investigated how the invasion of Spartina alterniflora affected the diversity, composition, and co-occurrence networks of soil bacterial and fungal communities in the Yellow River Delta, China. Compared to the native plant (Suaeda salsa), S. alterniflora invasion decreased the α-diversity of soil bacterial communities but did not affect that of fungal communities. The β-diversity of soil bacterial and fungal communities under S. salsa and S. alterniflora habitats also differed dramatically. S. alterniflora invasion increased the relative abundance of the copiotrophic phylum Bacteroidota, whereas decreased the relative abundances of the oligotrophic phyla Acidobacteriota and Gemmatimonadota. Additionally, the relative abundance of Chytridiomycota, known for its role in degrading recalcitrant organic matter, increased substantially within the soil fungal community. Functional predictions revealed that S. alterniflora invasion increased the relative abundance of certain soil bacteria involved in carbon and nitrogen cycling, including aerobic chemoheterotrophy, nitrate reduction, and nitrate respiration. More importantly, S. alterniflora invasion reduced the complexity and stability of both soil bacterial and fungal community networks. The shifts in soil microbial community structure and diversity were mainly induced by soil available nutrients and soil salinity. Overall, our study highlights the profound impacts of S. alterniflora invasion on soil microbial communities, which could further indicate the modification of ecosystem functioning by invasive species. [ABSTRACT FROM AUTHOR]

Soil salinity poses a significant threat to agricultural productivity, impacting the growth and yield of wheat (Triticum aestivum L.) plants. This study investigates the potential of melatonin (MT; 100 µM) and hydrogen sulfide (H2S; 200 µM sodium hydrosulfide, NaHS) to confer the tolerance of wheat plants to 100 mM NaCl. Salinity stress induced the outburst of reactive oxygen species (ROS) resulting in damage to the chloroplast structure, growth, photosynthesis, and yield. Application of either MT or NaHS augmented the activity of antioxidant enzymes, superoxide dismutase, ascorbate peroxidase, glutathione reductase, and reduced glutathione (GSH) levels, upregulated the expression of Na+ transport genes (SOS1, SOS2, SOS3, NHX1), resulting in mitigation of salinity stress. Thus, improved stomatal behavior, gas-exchange parameters, and maintenance of chloroplast structure resulted in enhanced activity of the Calvin cycle enzymes and overall enhancement of growth, photosynthetic, and yield performance of plants under salinity stress. The use of DL-propargylglycine (PAG, an inhibitor of hydrogen sulfide biosynthesis) and p-chlorophenyl alanine (p-CPA, an inhibitor of melatonin biosynthesis) to plants under salt stress showed the comparative necessity of MT and H2S in mitigation of salinity stress. In the presence of PAG, more pronounced detrimental effects were observed than in the presence of p-CPA, emphasizing that MT was involved in mitigating salinity through various potential pathways, one of which was through H2S. [ABSTRACT FROM AUTHOR]

The encroachment of woody shrubs in grass-dominated coastal salt marsh ecosystems has potentially influenced soil physical and chemical processes at various scales. Understanding the effects of shrub encroachment on those ecosystems requires assessments of the spatial heterogeneity in soil variables across multiple scales. Combined with GIS spatial tools and sampling data, we evaluated the vertical (0–80 cm) and spatial characteristics of soil pH and soil salinity (or electrical conductivity, EC) in a coastal wetland that experienced 40 years of shrub (specifically, the Tamarix chinensis species) encroachment. In order to obtain the information of the spatial patterns and scale domains of soil pH and EC, we employed the lacunarity analysis method. Furthermore, we utilized both Mantel test and Pearson correlation to identify their relationship. The results revealed that shrub encroachment had notable impacts on the magnitude and spatial patterns of soil pH and EC. These effects were driven by specific encroaching processes. Specifically, large shrub patches (SP) resulted in a significant rise in soil pH and a noteworthy reduction in soil EC. In addition, small shrub clusters (SC) caused a notable reduction in soil EC, but did not have significant impacts on soil pH. The impacts of shrubs on soil pH were primarily observed in 0–20 cm, whereas their effects on soil EC extended to deeper soil layers (e.g., up to 60 cm). Shrub encroachment also increased the landscape heterogeneity of both soil pH and EC, with the effects being more pronounced on soil EC. The lacunarity analysis revealed that the spatial heterogeneity of soil EC differed significantly among four depths, 0–20, 20–30, 30–60, and 60–80 cm, while the heterogeneity of soil pH varied significantly between two depths of 0–60 and 60–80 cm. Furthermore, soil pH and soil EC showed a strong spatial association, with a negative relationship observed between the two variables within each soil layer. Our study at the landscape scale highlights the opposite responses of soil pH and EC in saline-alkali wetlands to shrub encroachment. By understanding the impacts of shrubs on soil properties, we can enhance our ability to effectively restore and manage these degraded ecosystems. [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]

The matric suction of saline soil is the driving force that causes water migration, and it is of great significance for exploring the mechanism of water and salt migration in saline frozen soil. In order to investigate the effect of phase transition of soil pore solution induced by temperature on the matric suction of saline soil, the matric suction of different types of saline soils was measured by pF meter under different temperature conditions. The natural soil was first washed to obtain the desalinized soil, then different salt mass ratios of sodium chloride and sodium sulfate (0:6, 4:2, 2:4, 6:0) were added into the desalinized soil to model the composite saline soil, the salt content and water content were set to 6% and 20%, respectively. Subsequently, the remolded saline soil was compacted into the test chamber (0.37 m×0.25 m×0.22 m), and its dry density was controlled at 1.6 g/cm³. Hydra Probe II and pF meter were embedded at 11cm of the sample to measure the liquid water content and matric suction versus temperature. Freezing-thawing box (TMS 9 018-R30), produced by Zhejiang Tomos company, was employed to control the experimental temperature by step cooling method. The temperature range was from 30 to -24 °C, and the temperature interval was 3 °C. The data was collected by CR300 at an interval of 6 h. When the experiment was complete, the temperature effect of saline soil matric suction was analyzed and the effect of water/salt phase transition was explored. The experimental results reveal that the matric suction of saline soil increases almost linearly with the decrease of temperature when no phase transition occurs, which is caused by surface tension and wetting coefficient. Different types of saline soils have different effects on the phase transition process of pore solution, resulting in significant differences in the matric suction of different types of saline soils. The mirabilite crystallizes at 19 °C and the second phase transition occurs at -9 °C for the composite saline soil with 2% NaCl+4% Na2SO4, and the phase transition of composite saline soil with 4% NaCl+2% Na2SO4 occurs at 11 and -16 °C.Sodium chloride can inhibit the occurrence of ice formation, then the matric suction caused by ice formation is reduced, and the segregated frost heave caused by water migration is restrained indirectly. Besides, sodium sulfate is prone to crystallization at positive temperatures, and ice is also produced in the secondary phase transition process, both salt crystallization and ice formation increase the matric suction in sodium sulfate soil, and water and salt redistribute in this process, salt expansion and frost heave are induced. For composite saline soil, sodium sulfate mainly affects the salt crystallization of the soil at a positive temperature, while sodium chloride mainly affects the ice formation of the soil at a negative temperature. The different proportions of the two salts cause significant differences in the salt crystallization temperature and the secondary phase transition temperature, resulting in more complex phase transition laws in composite saline soil, and it is more difficult to predict the matric suction of composite saline soil. In addition, this paper further explores the contribution of ice and salt crystallization to the variation of matric suction, providing effective references for a deeper understanding of the relationship between phase transition processes and matric suction in saline soils. [ABSTRACT FROM AUTHOR]

Background and aim: Soil salinity presents major constraint for symbiotic root-microbe interactions and overall crop productivity. While compost amendments are effective, availability is limited in drylands where salinity is prevalent. As an alternative approach, we investigated the foliar application of signaling compounds. Methods: In this study, cowpea plants were evaluated under the treatments of foliar application of strigolactones (SL), salicylic acid (SA), SL and SA or SLSA, and coumarins (CMR), under soil amendment with gypsum (GP) and compost (CMP), and unamended natural saline soil as the control soil (CS) treatment. The microbiome structure in the rhizosphere, roots, leaves, and seeds were assessed, along with root traits, nodulation, arbuscular mycorrhizal (AMF) colonization, nutrient concentrations, and biomass yield. Results: Several treatments exhibited positive effects, with CMP and SLSA yielding the most comprehensive improvements. The SLSA outperformed CMP in enhancing nodulation and AMF colonization. Only CMP induced a significant shift in the rhizosphere and root microbiome structure, while the leaf and seed microbiomes remained stable. An AMF Rhizophagus in the rhizosphere and AMF Diversispora in the root endosphere of SLSA treatment, and Actinobacteria and Streptomyces in the root endosphere of the SLSA treatment showed increased abundance. The increased abundance of several microbial groups with SLSA indicated their effectiveness as beneficial keystone taxa, which appears to be an influential factor for impacting salinity tolerance in the legume. Conclusions: Overall, these findings confirm that the application of signaling compounds is a viable strategy for enhancing symbiotic root-microbe interactions and improving plant productivity in saline soils. [ABSTRACT FROM AUTHOR]

Nutrient cycling in desert ecosystems is heavily reliant on the fine root turnover and litter decomposition processes of dominant plant species. Based on field investigations and laboratory experiments, we explored fine root production (FRP) and turnover of Salsola passerina in Alxa steppe desert, and assessed fine root and leaf litter input and its correlation with soil C and N stocks, and then compared the variability of soil physicochemical properties at the site below and the interspace of S. passerina canopy. Results showed that fine root biomass dynamics of S. passerina were consistent with soil water content. Annual FRP of S. passerina was 243.3 g m−2 yr−1 and the turnover rate was 2.0 per year. S. passerina contributed 172.2 g C m−2 and 6.8 g N m−2 to soil from its fine root senescence and leaf litter input annually. Compared to the canopy interspace, the soil texture and fertility beneath the shrubs significantly improved, while the soil salinity decreased. The results indicated that the activities of desert shrub growth provided the degraded soil with abundant nutrients through fine root turnover and litter decomposition processes, which promoted soil texture and nutrition heterogeneity at the stand scale, and played an important role in degraded dryland restoration. [ABSTRACT FROM AUTHOR]

Spring‐fed wetlands within arid and semiarid systems are hotspots for endemism and distribution of rare plants. Interactions among groundwater and the geomorphic and climatic features of the setting control the abiotic conditions, particularly soil salinity and moisture, that support these plants. However, water uncertainty and land use change challenge the persistence of conditions necessary to support rare plant communities. Wetland management can be implemented to sustain abiotic processes that support rare plant communities, but key information is needed to guide management practices. In this study, we evaluate the relationships of rare plants to abiotic conditions in a managed spring‐fed arid wetland. Soil salinity and moisture conditions were monitored and related to the presence and abundance of rare plants within management units. Soil salinity and moisture variability were related to groundwater dynamics near springs, but wetland management influenced variability in seasonally flooded areas. Permanently saturated conditions and low soil salinities during the spring season supported higher plant diversity and the presence and greater abundance of rare plants. Rare plant presence and abundance were negatively related to low soil moisture, particularly in the summer. Results indicate that increases in soil salinity during the early establishment of plants may affect their distribution and abundance, an important management consideration in arid landscapes and hydrologically altered systems. Our findings inform the restoration and management of rare plant communities and contribute to the management of spring‐fed arid wetlands. [ABSTRACT FROM AUTHOR]

• Salt-coping strategies were studied investigating roots through a rhizoslide setup. • Different salt tolerance mechanisms were identified in the two halophyte species. • New Zealand spinach accumulated sodium and showed increased WUE at 100 mM NaCl. • Quinoa behaved as a sodium excluder with restricted growth at 100 mM NaCl. • Salinity affected both root architecture and plant transpiration. Soil salinity, root sodium concentration, and transpiration rate are important environmental factors impacting plant growth and productivity. This study investigates the salt-coping strategies of two plant species under varying salinity levels: New Zealand spinach species grown at three salinity levels (i.e., 0, 100, and 200 mM NaCl) and three varieties of quinoa, i.e., "Vikinga", "Dave 407" and "Red Head", grown with or without salt (i.e., 0 and 100 mM NaCl). The plants were grown on glass fiber sheets (rhizoslides) under controlled laboratory conditions. The relationship between transpiration rate, salinity, and root architecture was analyzed for each species. The root apparatus of New Zealand spinach was significantly more developed in plants grown at 100 mM NaCl compared to both 200 mM NaCl and control. The quinoa varieties responded differently to the increasing salt concentrations, with salt-treated "Red Head" plants significantly reducing their total root length and salt-treated "Vikinga" significantly reducing its lateral roots compared to the controls. Salt concentration near New Zealand spinach roots was lower compared to areas without roots, suggesting active salt uptake. In contrast, quinoa rhizoslides exhibited higher salt concentration in proximity to the roots, indicative of salt exclusion. The study provides insights into the adaptation and tolerance mechanisms of these two species to salinity, elucidating the mechanisms by which plants regulate their sodium uptake and root growth. The obtained results suggest that not only the selection of appropriate plant species (halophytes), but also varieties, plays a crucial role in improving crop productivity in salt-affected areas. Elucidating the salt-coping mechanisms of halophytes in relation to soil and climatic conditions is important to better predict their behavior in various saline environments. [ABSTRACT FROM AUTHOR]

Soil salinisation poses a significant threat to global agricultural production and food security. China is among the countries most severely impacted by soil salinisation. To investigate the improvement technology for saline–alkali stress in buckwheat, a typical multigrain crop in northwest China, a coupling regulation study using desulfurisation gypsum and polyacrylamide (PAM) was conducted in 2019 and 2020. Desulfurisation gypsum was applied at 0, 5.5, 11, 16.5 and 22 kg·ha−1, while PAM was applied at 0, 15, 30, 45 and 60 kg·ha−1. The results demonstrated that applying 11 t·ha−1 desulfurisation gypsum and 30 kg·ha−1 PAM effectively reduces soil salinity and pH, averaging 81.79% and 6.07%, respectively. Furthermore, it did not cause soil heavy metal pollution and created the best soil environment for buckwheat growth. Among the models tested, the nonrectangular hyperbolic model was the most accurate in describing buckwheat's photosynthetic light response. The optimal treatment for achieving the best photosynthetic performance—measured by apparent quantum efficiency, maximum net photosynthetic rate, light compensation point, light saturation point, dark respiration rate, stomatal conductance, intercellular CO2 concentration, transpiration rate, leaf water use efficiency and yield—was achieved through applying 11 t·ha−1 desulfurisation gypsum and 30 kg·ha−1 PAM. Therefore, desulfurised gypsum and PAM should be applied at 11 t·ha−1 and 30 kg·ha−1, respectively, to improve buckwheat's adaptability to different light intensities while promoting its photosynthetic response in saline–alkali soils. This study provides an effective technical scheme for reducing salt and promoting the growth of crops under salinity stress, which is of great significance for improving salinity land in arid areas. [ABSTRACT FROM AUTHOR]

Climate change is causing drastic reduction in crop yields around the globe due to increase in soil salinity, drought and heat stress. Quinoa (Chenopodium quinoa Willd) is regarded as a very significant food security crop considering the climate change scenario. Two quinoa genotypes (Puno and Titicaca) were cultivated on salt affected soil under drought stress with different sowing dates. Compared with early sowing, late sowing combined with salinity and drought stress caused drastic decline in plant growth and grain yield due to imposition of heat stress. Plant biomass and grain yield decreased by 26% and 39% in Puno, and by 34% and 49% in Titicaca under late sowing accompanied by salt and drought stress. Relative water contents and stomatal conductance of leaves declined in the same trend in both genotypes. Shoot Na+ concentration was the highest whereas K+ concentration was the lowest in both genotypes when drought and salt stress were combined under late sowing. Grain minerals (Ca, Mg, Fe, Zn, Cu, K, P, N and Mn) and dietary contents (protein, lipids, carbohydrates and fibre) were decreased more under the combination of salinity and drought for late sowing as compared to early sowing. When salinity and drought stress were combined under late sowing, the contents of H2O2 and TBARS were 1.9 and 2.2‐fold higher in Puno and 2.4 and 2.6‐fold higher in Titicaca, respectively. The oxidative stress was mitigated by enhanced activities of antioxidant enzymes (CAT, SOD and POD) more in Puno than Titicaca. Plant biomass and grain yield were higher in Puno with better grain quality than Titicaca. Hence, this genotype should be cultivated on salt affected soils facing drought and high temperatures. [ABSTRACT FROM AUTHOR]

The storage of organic carbon in the soils of salt marshes and other coastal blue carbon ecosystems has gained considerable attention by the scientific community for more than a decade now, while the relevance and mechanisms of soil inorganic carbon accumulation remain poorly understood. Using long‐term annual accretion monitoring over 17 years in N = 50 permanent plots distributed across a 1050‐ha salt‐marsh complex of the European Wadden Sea, we identified clear relationships between salt‐marsh vertical growth rates and the soil densities of inorganic and organic carbon. Specifically, we demonstrate a strong positive correlation between vertical accretion and inorganic carbon density while observing a strong negative correlation between vertical accretion and organic carbon density. This decoupling observed between inorganic and organic soil carbon stocks was governed by plant community composition and associated plant traits, which controlled sedimentation processes. [ABSTRACT FROM AUTHOR]

Excess soil salinity significantly impairs plant growth and development. Our previous reports demonstrated that the core circadian clock oscillator GIGANTEA (GI) negatively regulates salt stress tolerance by sequestering the SALT OVERLY SENSITIVE (SOS) 2 kinase, an essential component of the SOS pathway. Salt stress induces calcium‐dependent cytoplasmic GI degradation, resulting in activation of the SOS pathway; however, the precise molecular mechanism governing GI degradation during salt stress remains enigmatic. Here, we demonstrate that salt‐induced calcium signals promote the cytoplasmic partitioning of CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1), leading to the 26S proteasome‐dependent degradation of GI exclusively in the roots. Salt stress‐induced calcium signals accelerate the cytoplasmic localization of COP1 in the root cells, which targets GI for 26S proteasomal degradation. Align with this, the interaction between COP1 and GI is only observed in the roots, not the shoots, under salt‐stress conditions. Notably, the gi‐201 cop1‐4 double mutant shows an enhanced tolerance to salt stress similar to gi‐201, indicating that GI is epistatic to COP1 under salt‐stress conditions. Taken together, our study provides critical insights into the molecular mechanisms governing the COP1‐mediated proteasomal degradation of GI for salt stress tolerance, raising new possibilities for developing salt‐tolerant crops. Summary statement: Salt‐induced Ca2+ signal triggers E3 ubiquitin ligase CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) dependent proteasomal degradation of cytosolic GIGANTEA (GI) in the roots under salt‐stress conditions. Consequently, COP1‐regulated GI degradation positively regulates salt stress tolerance in Arabidopsis thaliana. [ABSTRACT FROM AUTHOR]

Soil salinity influences soil quality and other essential plant nutrients, reducing productivity and soil fertility in the Hatiya Upazila (Upazila is the second lowest tier of regional administration in Bangladesh), a coastal district of Noakhali, which is the soil saline vulnerable region of Bangladesh. This study determined the area’s soil salinity level, current crop production condition, and related soil salinity level of Hatiya Upazila. This research aimed to evaluate the effect of soil salinity on soil nutrients and other soil characteristics. To conduct this study, we randomly collected 78 soil samples from the 26 villages with three replicable samples from each sampling location and nine chemical characteristics of the soil samples evaluated. We mapped the soil salinity and other soil properties using the inverse distance weighting (IDW) interpolation techniques in ArcGIS software (version 10.8) environment. Also, we used Pearson’s correlation coefficient and linear regression models to evaluate the impact of soil salinity on the chemical properties of the soil. Results show that 38% of the study area has mild salinity, while 8% of the study area is affected by moderate salinity. In addition, around 4% of the study area is affected by high salinity. The reverse relation occurs when soil salinity is high and phosphorus, total nitrogen, organic matter, and carbon levels are low. According to statistical analysis, soil salinity (EC) is closely related to Na and K (r = 0.422). Soil salinity (EC) negatively affects OM, TN, P, and OC. The pH or sulphur content (EC) had no effect on the salinity of the soil. Among OCs, OM and TN have a favourable and strong relationship among themselves. These findings will benefit many stakeholders from the public and private sectors and local leaders in taking appropriate action to decrease the impact of soil salinity on agricultural production.Highlights: 1. To estimate the soil salinity level in current crop production and impact on soil components and nutrients. 2. OC and OM positively strongly correlated with each other (r = 0.90), and OM and TN also follow a positive strongly correlation (r = 0.877). 3. Organic carbon, organic matter, TN, and P showed a moderate negative correlation with ECe. [ABSTRACT FROM AUTHOR]

• Long-term dynamics of algal bloom patterns and their causative factors are assessed. • Time-series satellite data are analyzed and modelled using non-parametric methods. • Increased occurrence and reduction in the areal extent of algal blooms are observed. • The relative influence of ocean, atmosphere, and land parameters changes by regions. • Temporal prediction of blooms is possible with a time lag of 2 months. Algal blooms are global phenomena in marine and fresh waters. An understanding of the impacts of climate change and anthropogenic activities on marine algal blooms is essential for protecting marine ecosystems. We have studied the long-term changes in the spatial patterns of algal blooms over the northern Indian Ocean and assessed the influence of the ocean, atmosphere, and land-based processes on them. We have analyzed multi-source satellite data (2003 – 2020) of various parameters such as algal concentration, temperature, salinity, sea level, particulate organic carbon, precipitation, wind speed, and river discharge on an open-source cloud computing platform. The seasonality of variables is assessed using a harmonic model, and their spatial trend is estimated using the non-parametric Mann-Kendall test. The spatial relationship between various geophysical parameters and algal bloom concentration is assessed by the cross-correlation test, and the prediction is done using a multivariate autoregression model. Results suggest that each variable exhibits distinguishable seasonal patterns. Algal bloom duration showed a significant increase over time. However, algal bloom coverage showed a significant decline in the coastal waters in all seasons except post-monsoon. The cross-correlation test unveils that lower temperatures, salinity, and sea level promote algal bloom occurrences in coastal waters rather than open waters. Furthermore, the statistical model with a time lag of 2 months shows better performance for prediction of bloom intensity (r2 = 0.86). [ABSTRACT FROM AUTHOR]

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Hydrangea macrophylla is a shrub endemic to Japan, and inhabits the limited coastal zones in the Izu, Miura and Boso peninsulas, and the Izu and Bonin islands. Even though H. macrophylla is demanded as an important genetic resource for ecological conservation and utilities of landscaping and gardening in salinity-stressed lands, there is still a lack of information regarding its ecology and adaptative response to salinity-stressed coastal environments. This study aimed to understand the ecology and adaptation to salinity stress of H. macrophylla. Thus, we examined distribution, geography, vegetation, morphology, soil characteristics, and cation concentrations of the leaves in the native habitats. Most of the populations were mainly distributed in coastal zones that have sea-salt aerosols triggered by high wind speed and high soil salinity, causing severe damage to other plant species. The cation analysis suggested H. macrophylla adapted to coastal zones by regulating Na+ allocation of leaves and tolerating to high Na+ concentration. Otherwise, we found many populations inhabited inland or semi-coastal areas with mountainous vegetation in Izu islands. They had thinner leaves with weaker glossy, and some individuals developed trichomes which are not originally present in H. macrophylla, suggesting in initial stage of the process of adaptative radiation to mountainous environment. The other individuals grew in oligotrophic environments such as rocky surfaces and volcanic ash scoria, and epiphyte-like individuals inhabited stem surfaces of Cyathea spinulosa, implying these individuals had adaptability to oligotrophic environments. The comprehensive information should help facilitate further studies on ecological conservation and horticultural utilities. [ABSTRACT FROM AUTHOR]

Crop rotation increases crop yield, improves soil health, and reduces plant disease. However, few studies were conducted on the use of intensive cropping patterns to improve the microenvironment of saline soils. The present study thoroughly evaluated the impact of a three-year maize–peanut–millet crop rotation pattern on the crop yield. The rhizosphere soil of the crop was collected at maturity to assess the effects of crop rotation on the composition and function of microbial communities in different tillage layers (0–20 cm and 20–40 cm) of sandy saline–alkaline soils. After three years of crop rotation, the maize yield and economic benefits rose by an average of 32.07% and 22.25%, respectively, while output/input grew by 10.26%. The pH of the 0–40 cm tillage layer of saline–alkaline soils decreased by 2.36%, organic matter rose by 13.44%–15.84%, and soil-available nutrients of the 0–20 cm tillage layer increased by 11.94%–69.14%. As compared to continuous cropping, crop rotation boosted soil nitrogen and phosphorus metabolism capacity by 8.61%–88.65%. Enrichment of Actinobacteria and Basidiomycota increased crop yield. Crop rotation increases microbial community richness while decreasing diversity. The increase in abundance can diminish competitive relationships between species, boost synergistic capabilities, alter bacterial and fungal community structure, and enhance microbial community function, all of which elevate crop yields. The obtained insights can contribute to achieving optimal management of intensive cultivation patterns and green sustainable development. [ABSTRACT FROM AUTHOR]

In the context of increasing agricultural challenges posed by soil salinity and drought stress, the main importance of the present study was to evaluate some novel treatments for improving canola productivity and resilience by applying wood distillate (WD) in combination with bagasse ash (SBA). A two-year field experiment using a split plot design was conducted and evaluated several physiological and biochemical parameters under different irrigation regimes conducted at 80% and 50% field capacity. While there were considerable moderation effects of SBA and WD on soil salinity, expressed as exchangeable sodium percentage (ESP), under both well-irrigated and drought conditions, more importantly, the ESP was reduced to 31% under drought stress with combined WD and SBA applications over any single factor. WD and SBA treatments of canola leaves showed reduced Na content with increased K levels, and the plants maintained physiological attributes—chlorophyll content, stomatal conductance, and relative water content—to the level of controls of well-irrigation. Besides, they significantly alleviated oxidative stress by decreasing the hydrogen peroxide (H2O2), malondialdehyde (MDA), and electrolyte leakage (EL) levels and increasing the activities of antioxidant enzymes like superoxide dismutase (SOD) and ascorbate peroxidase (APX). Nonenzymatic antioxidants such as total soluble sugars (TSS), total soluble proteins (TSP), total phenolic content (TPC), and total flavonoid content (TFC) were significantly increased under stress conditions with a special accent on combined treatment, whereas the levels of proline and GB that increased in alignment with drought reduced under the combined application. Various growth parameters of plants like plant height, number of branches, and siliques per plant were significantly improved with WD and SBA under drought stress. Principal component analysis (PCA) and Pearson correlation further confirmed the relationships among these parameters and thus underpinned that WD and SBA can evoke a synergistic effect to enhance growth promotion and stress tolerance in canola. This, therefore, infers that the combined application of WD and SBA can be key, offering very high potential as viable options to better canola productivity under adverse environmental conditions. [ABSTRACT FROM AUTHOR]

Kentucky bluegrass (Poa pratensis L.), a widely used cool-season turfgrass, shows a high sensitivity to soil salinity. Clarifying the adaptative mechanisms of Kentucky bluegrass that serve to improve its salt tolerance in saline environments is urgent for the application of this turfgrass in salt-affected regions. In this study, physiological responses of the Kentucky bluegrass cultivars "Explorer" and "Blue Best" to NaCl treatment, as well as gene expressions related to photosynthesis, ion transport, and ROS degradation, were analyzed. The results showed that the growth of "Explorer" was obviously better compared to "Blue Best" under 400 mM NaCl treatment. "Explorer" exhibited a much stronger photosynthetic capacity than "Blue Best" under NaCl treatment, and the expression of key genes involved in chlorophyll biosynthesis, photosystem II, and the Calvin cycle in "Explorer" was greatly induced by salt treatment. Compared with "Blue Best", "Explorer" could effectively maintain Na+/K+ homeostasis in its leaves under NaCl treatment, which can be attributed to upregulated expression of genes, such as HKT1;5, HAK5, and SKOR. The relative membrane permeability and contents of O2− and H2O2 in "Explorer" were significantly lower than those in "Blue Best" under NaCl treatment, and, correspondingly, the activities of SOD and POD in the former were significantly higher than in the latter. Moreover, the expression of genes involved in the biosynthesis of enzymes in the ROS-scavenging system of "Explorer" was immediately upregulated after NaCl treatment. Additionally, free proline and betaine are important organic osmolytes for maintaining hydration status in Kentucky bluegrass under NaCl treatment, as the contents of these metabolites in "Explorer" were significantly higher than in "Blue Best". This work lays a theoretical basis for the improvement of salt tolerance in Kentucky bluegrass. [ABSTRACT FROM AUTHOR]

Reduction in soil salinity in the entire project area is a key indicator of proper functioning of the implemented subsurface drainage (SSD) projects. Electromagnetic induction (EMI) surveys were carried out to facilitate spatiotemporal assessment of soil salinity of a SSD project site in Kahni, Haryana (India). The surveys were conducted in two time frames: immediately after the start of SSD project in 2019 and after 2 years of successful operation in 2021. The collected data of 2 surveys was used to derive a depth‐specific calibrated correlation between the observed salinity (ECe) of collected soil samples and surveyed apparent electrical conductivity (ECa) observations in vertical (ECav) and horizontal (ECah) modes. Spatiotemporal analysis of soil salinity revealed notable changes in areas under different salinity classes over a period of 2 years, indicating the impact of SSD on soil desalinization. During the course of 2 years (2019–2021) of SSD operation, area under moderate salinity (4–8 dS m−1) in the top 0–0.15 m soil increased by 54.5% while it decreased by 40% and 6.6% under high (8–12 dS m−1) and very high (12–16 dS m−1) salinity classes. The rice and wheat yields were also enhanced by 24% and 7% respectively after 2 years operation of SSD in hitherto severally waterlogged saline soils. Overall findings of this study reinforce the scope of using EMI approach to quickly and effectively assess the efficacy of subsurface drainage. Creation of measurable soil salinity maps by proposed EMI and GIS techniques can help in planning and implementing site‐specific management strategies in saline soil reclamation projects. [ABSTRACT FROM AUTHOR]

Bassia indica (Wight) A. J. Scott is a fast-growing halophyte suitable for the remediation of saline lands on a large scale. However, no information is available regarding its phytoremediation potential for cadmium (Cd) alone or in combination with salinity. Besides evaluating phytoremediation, assessing micronutrient hemostasis as a crucial physiological insight into the mechanism involved in the tolerance of B. indica under saline soil contaminated with Cd was subjected. Under salinity stress, a considerable amount of sodium accumulates in the plant. Moreover, the accumulation of sodium increased by Cd stress levels. The increase in the exchangeable form of Cd in the rhizosphere in the presence of NaCl ions further elevated the Cd content in the plant tissues. For instance, compared to non-saline conditions, applying 2.5 and 5 g NaCl kg−1 to soil treated with 60 mg Cd kg−1 increased exchangeable Cd by 28.4 and 49.5% in rhizosphere soil, which led to increased cadmium content by 16.1 and 29.6% in the root (as a main part of Cd accumulation), respectively. Under most stress conditions, potassium homeostasis in the shoot remained undisturbed. It was observed that this plant could transfer an optimal level of potassium from the roots to the shoots at a moderate salinity level. Changes and the distribution of Cu and Zn levels followed a similar pattern in the plant, indicating a common regulation mechanism for these nutrients. Generally, the plant could maintain an appropriate level of Fe, Zn, and Cu ions under most stressed conditions. However, the level of Mn decreased significantly under severe stress levels. Growth parameters, tolerance index, and the values of translocation factor < 1 and shoot bioconcentration factor > 1 under 5 mg Cd kg−1 soil treatment at different salinity levels indicated that B. indica could mitigate the detrimental effect of Cd toxicity and tolerate the NaCl stress via a phytostabilizer mechanism. However, the shoot bioconcentration factor values were very close to one at other Cd levels. Therefore, considering the obtained evidence and the innate ability of B. indica to remediation salinity, this plant is still recommended, even for higher Cd levels (even until 30 mg kg−1), in the presence of salinity. [ABSTRACT FROM AUTHOR]

[Objective] To reveal the present situation and problems of soil in Beijing-Tianjin-Hebei fruit and vegetable base. [Method] Taking soil of Raoyang fruit and vegetable base as the evaluation object in Hebei Province, 12 soil samples were collected, the main physical and chemical property indicators were determined, the soil salinity was evaluated, and correlation analysis was carried out; the fuzzy evaluation method was used to evaluate the soil fertility; the status of soil heavy metals was evaluated by the comprehensive quality impact index evaluation method. [Result] The soil in Raoyang fruit and vegetable base was alkaline, and the soil appeared weak secondary salinization. The electrical conductivity increased with the increase of salt content, and the phenomenon of alkalization occurred at the same time as the salinization. The soil fertility level was at a moderate level. The evaluation results of soil heavy metal pollution showed that different degrees of heavy metal accumulation occurred in the study area, which may be related to the unreasonable fertilization methods, which had potential risks and needs to be paid attention to. The conversion of orchards to greenhouse vegetable cultivation significantly reduced the content of soil organic matter and increased the risk of soil salinization. [Conclusion] The research results provide scientific basis for the rational use of land, rational fertilization, soil nutrient management and high-quality fruit and vegetable production in the fruit and vegetable base of Raoyang County. [ABSTRACT FROM AUTHOR]

With the continuous expansion of saline soils under climate change, understanding the eco-evolutionary tradeoff between the microbial mitigation of carbon limitation and the maintenance of functional traits in saline soils represents a significant knowledge gap in predicting future soil health and ecological function. Through shotgun metagenomic sequencing of coastal soils along a salinity gradient, we show contrasting eco-evolutionary directions of soil bacteria and archaea that manifest in changes to genome size and the functional potential of the soil microbiome. In salt environments with high carbon requirements, bacteria exhibit reduced genome sizes associated with a depletion of metabolic genes, while archaea display larger genomes and enrichment of salt-resistance, metabolic, and carbon-acquisition genes. This suggests that bacteria conserve energy through genome streamlining when facing salt stress, while archaea invest in carbon-acquisition pathways to broaden their resource usage. These findings suggest divergent directions in eco-evolutionary adaptations to soil saline stress amongst microbial clades and serve as a foundation for understanding the response of soil microbiomes to escalating climate change. From metagenomic sequencing of coastal soils along a salinity gradient, this study shows contrasting eco-evolutionary strategies for relieving carbon limitation under salt stress in bacteria and archaea. The findings suggest that bacteria conserve energy through genome streamlining when facing salt stress, while archaea invest in carbon-acquisition pathways to broaden their resource usage. [ABSTRACT FROM AUTHOR]

Salinization is a major soil degradation process threatening ecosystems and posing a great challenge to sustainable agriculture and food security worldwide. This study aimed to evaluate the potential of state-of-the-art machine learning algorithms in soil salinity (EC1:5) mapping. Further, we predicted the distribution patterns of soil salinity under different future scenarios in the Yellow River Delta. A geodatabase comprising 201 soil samples and 19 conditioning factors (containing data based on remote sensing images such as Landsat, SPOT/VEGETATION PROBA-V, SRTMDEMUTM, Sentinel-1, and Sentinel-2) was used to compare the predictive performance of empirical bayesian kriging regression, random forest, and CatBoost models. The CatBoost model exhibited the highest performance with both training and testing datasets, with an average MAE of 1.86, an average RMSE of 3.11, and an average R2 of 0.59 in the testing datasets. Among explanatory factors, soil Na was the most important for predicting EC1:5, followed by the normalized difference vegetation index and soil organic carbon. Soil EC1:5 predictions suggested that the Yellow River Delta region faces severe salinization, particularly in coastal zones. Among three scenarios with increases in soil organic carbon content (1, 2, and 3 g/kg), the 2 g/kg scenario resulted in the best improvement effect on saline–alkali soils with EC1:5 > 2 ds/m. Our results provide valuable insights for policymakers to improve saline–alkali land quality and plan regional agricultural development. [ABSTRACT FROM AUTHOR]

Due to its readily soluble nature in groundwater and surface water, an excess accumulation of soluble salts in the soil, especially sodium chloride (NaCl), could pose serious threats to crop growth and development by disrupting physiological and biochemical processes in plants. The excess of soluble salt could originate from natural processes, such as weathering (physical or chemical) of parent rock materials, wind, and rainfall, and is thus termed as primary soil salinization. Besides, various anthropogenic activities, such as irrigation with brackish or saline water, poor land and water management, overuse of synthetic fertilizers, overextraction of groundwater, and saltwater intrusion into coastal aquifers as a result of sea level rise, could also create a salinity problem, which is known as secondary soil salinization. The salinity problem in soil and land of arid and semi-arid regions is even more severe. The concentration of salt is referred to as the sum of cation and anion or only cation or anion and is expressed as mg L-1. However, it is commonly measured as electrical conductivity (EC) of saturated soil extract (ECe) for scientific and analytical purposes and is expressed with a unit of decisiemens per meter (dS m-1). Salinity is a multi-dimensional stress for plants, impairing plant growth and development through cytotoxicity caused by excessive uptake of Na+ and Cl- ions, water stress, and nutritional imbalance. In addition, salinity is generally accompanied by oxidative stress because of the overproduction of reactive oxygen species. The water scarcity phase of salinity results in substantial yield loss through rapid inhibition of growth and development, while the ionic toxicity phase causes rapid leaf senescence through a variety of adverse impacts on cellular components simultaneously. Moreover, prooxidants generation at higher levels of salt stress threatens standard metabolic processes and poses a risk of irreversible damage on biomembranes, cellular organelles, nucleic acids, and proteins. Such constraints make cropping a great challenge in salt-affected areas; however, naturally salt-tolerant plants, also known as halophytes or semi-halophytes, can easily withstand comparatively higher salt concentrations because of their adaptive morpho-physiological and molecular mechanisms. Unlike halophytic or semi-halophytic plants, most of the commonly cultivated crops fail to tolerate salt stress as they fall under glycophyte or salt-susceptible category. However, the process of natural selection coupled with developing agricultural technologies has played a substantial role in imparting greater tolerance of crops to salt stress over the past few decades. Nevertheless, rapid sea level rise driven by anthropogenic climate change affecting the salinity of surface and groundwater in coastal areas and persistent spreading of salinity both in terms of land area and concentration call for a combined approach of compatible cultivar development and adoption of suitable management strategies. This necessitates a systematic and in-depth understanding of existing adaptations, tolerance mechanisms, and cultivation methods for stepping forward in strategizing future crop yield improvement programs. Therefore, the present review focuses on highlighting (i) the factors intensifying salinity problem in soils, (ii) salinity dynamics in plants including its uptake, transport, storage, and development of stress, (iii) salinity sensing mechanism in plants, (iv) naturally occurring adaptations, (v) genetic variabilities, and (vi) tolerance mechanisms available within cultivable crop germplasms with specific emphasis on morphological and anatomical tolerance, physiochemical tolerance, and role of genetic resources in enhancing tolerance against salinity. A number of agronomic, cultural, and technological management options to alleviate the adverse impacts of salt stress on crop plants are also discussed in this review, which could potentially offer invaluable information for the development of salt-tolerant crop improvement programs and optimized land and water management practices. [ABSTRACT FROM AUTHOR]

The morphological adjustments of euhalophytes are well-known to be influenced by the soil-soluble salt variation; however, whether and how these changes in morphological traits alter the biomass allocation pattern remains unclear, especially under different NaCl levels. Therefore, an allometric analysis was applied to investigate the biomass allocation pattern and morphological plasticity, and the carbon (C), nitrogen (N), and phosphorus (P) stoichiometric characteristics of the euhalophyte Suaeda Salsa (S. salsa) at the four soil-soluble salt levels of no salt (NS), light salt (LS), moderate salt (MS), and heavy salt (HS). The results showed that soil-soluble salts significantly change the biomass allocation to the stems and leaves (p < 0.05). With the growth of S. salsa, the NS treatment produced a downward leaf mass ratio (LMR) and upward stem mass ratio (SMR); this finding was completely different from that for the salt treatments. When S. salsa was harvested on the 100th day, the HS treatment had the highest LMR (61%) and the lowest SMR (31%), while the NS treatment was the opposite, with an LMR of 44% and an SMR of 50%. Meanwhile, the soil-soluble salt reshaped the morphological characteristics of S. salsa (e.g., root length, plant height, basal stem diameter, and leaf succulence). Combined with the stoichiometric characteristics, N uptake restriction under salt stress is a vital reason for inhibited stem growth. Although the NS treatment had the highest biomass (48.65 g root box−1), the LS treatment had the highest salt absorption (3.73 g root box−1). In conclusion, S. salsa can change its biomass allocation pattern through morphological adjustments to adapt to different saline–alkali habitats. Moreover, it has an optimal biological desalting effect in lightly saline soil dominated by NaCl. [ABSTRACT FROM AUTHOR]

Soil salinization will affect 50% of global cropland areas by 2050 and represents a major threat to agricultural production and food sovereignty. As soil salinity monitoring is costly and time consuming, many regions of the world undertake very limited soil salinity observation (in space and time), preventing the accurate assessment of soil salinity hazards. In this context, this study assesses the relative performance of Sentinel-1 radar and Sentinel-2 optical images, and the combination of the two, for monitoring changes in soil salinity at high spatial and temporal resolution, which is essential to evaluate the mitigation measures required for the sustainable adaptation of agriculture practices. For this purpose, an improved learning database made of 863 soil electrical conductivity (i.e., soil salinity) observations is considered for the training/validation step of a Random Forest (RF) model. The RF model is successively trained with (1) only Sentinel-1, (2) only Sentinel-2 and (3) both Sentinel-1 and -2 features using the Genetic Algorithm (GA) to reduce multi-collinearity in the independent variables. Using k-fold cross validation (3-fold), overall accuracy (OA) values of 0.83, 0.88 and 0.95 are obtained when considering only Sentinel-2, only Sentinel-1 and both Sentinel-1 and -2 features as independent variables. Therefore, these results highlight the clear complementarity of radar (i.e., Sentinel-1) and optical (i.e., Sentinel-2) images to improve soil salinity mapping, with OA increases of approximately 10% and 7% when compared to Sentinel-2 and Sentinel-1 alone. Finally, pre-sowing soil salinity maps over a five-year period (2019–2023) are presented to highlight the benefit of the proposed procedure to support the sustainable management of agricultural lands in the context of soil salinization on a regional scale. [ABSTRACT FROM AUTHOR]

Saline‐alkali soil degradation is a significant environmental problem with a negative impact on sustainable agroforestry development. Therefore, efficient remediation methods are urgently required. A potential solution to this problem is using biochar produced from bamboo waste and inoculated with plant growth‐promoting microbes as cleaner production materials for saline‐alkali soil. The present study investigated the potential of combining biochar, microbes, and dwarf bamboo to improve saline‐alkali soil. Different application rates (1%, 3%, and 5% of soil mass) of biochar were added to coastal saline soil planted with dwarf bamboo (Pleioblastus argenteastriatus) in pot experiments. Soil physicochemical properties, microbial communities, and plant responses were systematically studied. Bamboo and microbial‐modified biochar effectively decreased soil pH and electrical conductivity and increased soil nutrient contents. Compared with untreated soil, the relative abundance of the dominant bacterial phyla Acidobacteria, Actinobacteria, and Chloroflexi, and dominant fungal phyla Basidiomycota increased after applying biochar and modified biochar. With the increase in application concentration, the antioxidant activities of modified biochar decreased, biochar peroxidase and catalase content decreased, and the malondialdehyde content of bamboo biochar and microbial‐modified bamboo biochar decreased. The biomass of bamboo with added biochar and modified biochar was significantly higher than that of untreated soil. Comprehensive correlation and redundancy analyses showed that the bacterial and fungal communities were greatly affected by soil factors, especially soil pH, electrical conductivity, total organic carbon, potassium, and sodium ions. The findings of this study suggest that 5% bamboo biochar and 3% modified biochar benefit soil remediation, improve the stress resistance of dwarf bamboo, and enhance plant growth. Therefore, combined biochar–microbe remediation has great potential for the sustainable improvement of saline‐alkali soil. [ABSTRACT FROM AUTHOR]

ABSTRACT Soil salinity is a worldwide problem threatening crop yields. Some plant growth‐promoting rhizobacteria (PGPR) could survive in high salt environment and assist plant adaptation to stress. Nevertheless, the genomic and metabolic features, as well as the regulatory mechanisms promoting salt tolerance in plants by these bacteria remain largely unknown. In the current work, a novel halotolerant PGPR strain, namely, Bacillus sp. strain RA can enhance tomato tolerance to salt stress. Comparative genomic analysis of strain RA with its closely related species indicated a high level of evolutionary plasticity exhibited by strain‐specific genes and evolutionary constraints driven by purifying selection, which facilitated its genomic adaptation to salt‐affected soils. The transcriptome further showed that strain RA could tolerate salt stress by balancing energy metabolism via the reprogramming of biosynthetic pathways. Plants exude a plethora of metabolites that can strongly influence plant fitness. The accumulation of myo‐inositol in leaves under salt stress was observed, leading to the promotion of plant growth triggered by Bacillus sp. strain RA. Importantly, myo‐inositol serves as a selective force in the assembly of the phyllosphere microbiome and the recruitment of plant‐beneficial species. It promotes destabilizing properties in phyllosphere bacterial co‐occurrence networks, but not in fungal networks. Furthermore, interdomain interactions between bacteria and fungi were strengthened by myo‐inositol in response to salt stress. This work highlights the genetic adaptation of RA to salt‐affected soils and its ability to impact phyllosphere microorganisms through the adjustment of myo‐inositol metabolites, thereby imparting enduring resistance against salt stress in tomato. [ABSTRACT FROM AUTHOR]

Salinity is an abiotic factor limiting plant fitness and therefore forest crop productivity, and salt-affected areas have been expanding throughout the world. Ectomycorrhizal (ECM) fungi can improve the salt tolerance of woody plants, including Eucalyptus species To screen for salt-resistant Pisolithus albus (PA) isolates, 16 PA isolates were cultivated on modified Melin-Norkrans agar containing NaCl at concentrations of 0, 10, 20, and 30 dS m−1. The P. albus isolate PA33 had the greatest salt resistance under 10 and 20 dS m−1 NaCl, which are soil salinity levels in salt-affected areas of Thailand. We studied the effect of PA33 on Eucalyptus camaldulensis × E. pellita cuttings under salt stress (0 and 16 dS m−1) for 1 month. PA enhanced the growth of the Eucalyptus seedlings, as indicated by higher relative growth rates in height and root collar diameter of inoculated seedlings compared with non-inoculated seedlings. Moreover, the inoculated seedlings had less cell damage from NaCl, as indicated by significantly lesser leaf thickness and electrolyte leakage than the controls. These findings could lead to practices conferring socioeconomic and environmental benefits, as abandoned salt-affected areas could be reclaimed using such Eucalyptus seedlings inoculated with salt-tolerant ECM fungi. [ABSTRACT FROM AUTHOR]

Background: Yield gap is distance between potential yield and attainable yield (yield gap= potential yield-attainable yield) in order to increase the crop yield and the goal of sustainable agriculture. Methods: This study was conducted in Bam, Narmashir and Fahraj counties in 219 separate farms (79 farms in Bam, 72 farms in Narmashir and 68 farms in Fahraj) during the years 2019 and 2020 to investigate the yield gap of wheat and determine the limiting factors and their contributions to yield reduction, using the Comparative Performance Analysis (CPA) method. All information related to soil factors, management factors, climatic factors and agronomic traits (53 variables) were measured and recorded. The relationship between wheat yield and all variables was examined using a stepwise multiple regression method. A production model was determined for soil and management factors. Result: The results showed a yield gap between actual yield and potential yield in the regions of Bam, Narmashir and Fahraj, which were 1770.8, 1817.61 and 1605 kg per hectare, respectively. Since the actual yield in these regions was 4248, 4228 and 3161 kg per hectare, the yield gap was observed to be 33.6%, 30% and 29.4%, respectively. The effective factors in reducing the yield in the Bam region included water shortage (19.48%), nitrogen deficiency (16.09%), delayed planting (15.40%), soil available phosphorus deficiency (10.14%), weed density (10.8%), soil organic carbon (13.59%) and inappropriate plant density (14.47%). In the Narmashir region, water shortage (26.68%), nitrogen deficiency (18.86%), soil organic carbon (11.78%), inappropriate plant density (12.43%), wheat aphid (19.58%) and weed density (10.64%) caused yield reduction. In the Fahraj region, water shortage (20.65%), nitrogen deficiency (19.62%), delayed planting (9.44%), soil available phosphorus deficiency (8.45%), weed density (12%), soil salinity (12.80%) and black stem disease (17%) caused a decrease in wheat yield. [ABSTRACT FROM AUTHOR]

The degree of salinity, the freezing point, and the amount of unfrozen water are key factors in predicting the temperature, humidity, and mechanical behavior of saline permafrost soils used in construction as foundations for buildings. The results of the experimental studies are presented and a method for calculation of the amount of unfrozen water in saline soils is proposed. The calculated and experimental data show good convergence for both sandy and clay soils of different salinity and water content. [ABSTRACT FROM AUTHOR]