Effects Of Soil Salinity Research Articles

TRANSPIRATION RATES OF WINTER WHEAT CULTIVARS UNDER SALINE CONDITIONS

The article presents the data obtained on the study of the characteristics of the effect of soil salinity on the transpiration rate of winter wheat varieties. The rate of transpiration was determined at the tuber, flowering and milk-ripening stages of the cultivars. Based on the given results, it was noted that the value of the above indicator varies to different degrees in the section of varieties, depending on the soil salinity and the biological and various characteristics of the varieties.

SALINITY AND PHYSIOLOGICAL CHARACTERISTICS OF SOYBEAN VARIETIES

The article presents the data obtained on the study of the effect of soil salinity on some physiological characteristics of different soybean varieties. A decrease in the rate of transpiration and total water content was found in all varieties under conditions of saline soils. Based on the given results, it was noted that the above indicators change in various degrees in the section of the varieties and are related to the soil salinity and biological and varietal properties of the varieties, as well as the level of tolerance to salt.

Assessment of physico-chemical properties of soil in selected areas of Khambhat taluka, Gujarat

The present study was carried out in Khambhat, Gujarat, to study the different soil properties affected by salinity. The effects of soil salinity comprise low agricultural productivity, low economic returns, soil erosion or desertification. The assessment of this type soil is important to adopt appropriate management practices for reducing salinity from the soil. Soil samples were collected seasonally from different villages of Khambhat taluka. Soil samples were assessed for the physico-chemical parameters such as moisture content, pH, electric conductivity (EC), water holding capacity (WHC), soil texture, organic carbon (OC), organic matter (OM),nitrogen, phosphorus, potassium and micronutrients such as Cu, Zn, Fe, Mn. As observed in the results of pH (9.88), EC (9.45 dSm-1) and sodium (8565.15 µgkg-1) which is found higher in winter season. The available potassium, magnesium and calcium ranged from 315.17-1567 kgha-1, 1207.56-3120.37 mgkg-1 and 2346-4567.65 mgkg-1, respectively. The concentrations of micro-nutrients (Cu, Zn & Fe) were lower or limited in the soils of Khambhat taluka. Seasonal variations in soil properties are also important for future work. This present study helps to identify the soil nutrient availability and limiting factors for the crop production in these villages of Khambhat.

EFFICIENCY OF MACHINE LEARNING ALGORITHMS IN SOIL SALINITY DETECTION USING LANDSAT-8 OLI IMAGERY

Abstract. Climate change is one of the biggest problems facing today’s world. Rising temperatures and declining rainfall have had a profound effect on the planet, one of which is the destructive effects of soil salinity. Soil salinity phenomena commonly occur in arid and semi-arid regions. Maharloo Salt Lake, southeast of Shiraz, Iran, with an arid and semi-arid climate, has faced severe droughts in the past and is dealing with the soil salinity problem. One useful way to manage land and soil in such areas is regular monitoring of the soils and lands and keeping abreast of changes to prevent land degradation and erosion. With the advancement of technology, remote sensing techniques to monitor natural factors have become very popular. Landsat sensor images were used in this research, and several environmental indicators were extracted by combining satellite bands. Three machine learning algorithms, RF, GBM, and MLP, were used to evaluate methods for monitoring and mapping saline soils. The models were trained and then tested to compare the accuracy and performance of each model in predicting soil salinity. GBM algorithm showed the best performance with R2 = 0.89 and RMSE = 0.63 for testing the dataset after that RF model with R2 = 0.85 and RMSE = 0.71 and the worst performance was for MLP model with R2 = 0.75 and RMSE = 0.88. The figures mapped from the results of these algorithms for salinity distribution in this region showed that by choosing the appropriate algorithm and suitable in-situ data, it could be possible to estimate soil salinity to an excellent extent by satellite data.

Evaluation of the effect of soil salinity on the crop coefficient (Kc) for cotton (Gossypium hirsutum L.) under mulched drip irrigation in arid regions

Evaluation of the effect of soil salinity on the crop coefficient (Kc) for cotton (Gossypium hirsutum L.) under mulched drip irrigation in arid regions

Effect of soil salinity on eco-meliorative condition

This article represents recommendations for the gradual acceleration of agricultural production, the rational use of land resources, the solution of problems related to increasing the productivity and economic efficiency of each hectare of irrigated land, as well as practical advice.

Dual Asymmetric Response of Leaf-Level CO2Fixation to Changes in Seasonal Precipitation Distribution in a Coastal Marsh

Photosynthetic characteristics of dominant plant species are widely used as indicators of ecosystem responses to global environmental changes such as precipitation change. How different plant species respond physiologically to seasonal precipitation change in coastal marshes is largely unclear. Spring is a critical stage for plant colonization and growth, and a field experiment was conducted to study the response in leaf carbon fixation of dominant plant species to 5 seasonal precipitation distribution treatments [+73%, +56%, control (CK), −56%, and −73%] in coastal marshes. Results showed a dual asymmetric response of the maximum photosynthetic rate (Pn max) of dominant species (Phragmites australis) to spring precipitation distribution (SPD), showing thatPn maxwas more sensitive to increased than decreased SPD, and the effect size of increased SPD on it was approximately 2.4 times greater than decreased SPD under the −56% to +56% precipitation ranges. On the contrary, when the precipitation distribution range was further extended to ±73%,Pn maxmore sensitive to decreased than increased SPD, and the effect size of decreased SPD on it was approximately 2 times greater than increased SPD. The structural equation modeling revealed that the effect of SPD onPn maxis primarily mediated by the direct effect of soil salinity andgsand the indirect effect of soil water content, which determined the magnitude direction of the effect of SPD onPn max. Our findings demonstrate that soil salinity is the main controlling factor for the carbon sequestration of leaves under SPD in a coastal marsh. This leads to adaptive strategies for functional traits of dominant species, which, in turn, influence leaf-level CO2fixation and the carbon sink function of the entire ecosystem.

Osmotic characteristics of water retention structures of Bursera microphylla in relation to soil salinity

With a worldwide increase in soil salinity, as well as the climate crisis raising global temperatures, it is important to understand the effects of soil salinity on plant survival. One way to understand how plants may evolve to survive in these xeric desert environments is to gain a further understanding of existing halophytic (live in saline environments) and/or xerophytic (live in dry, arid environments) plants. Bursera microphylla in particular is quite interesting because it is both a halophyte and a xerophyte. One reason it is able to survive in dry environments is due to its bulbs at the base of the trunk and major limbs of the tree, which have been shown to store water during droughts. To facilitate mineral uptake, plants use ATP to transport NaCl ions into the plant, which facilitates water uptake. Because observed field conditions in the Baja California Peninsula were extremely xeric, most plants there have distinct evolutionary traits to facilitate water storage or retention. The Elephant Tree (Bursera microphylla) gets its name from the abnormal proportions of the base of its stem, which is much wider than much of the tree, and studies show that this disproportionately wide stem can store water for use during times of drought, which are common in the Baja California Peninsula. Our hypothesis was that sodium chloride was taken up through the plant’s root structure to facilitate this water transportation, and that this sodium chloride accumulation was directly proportional to the soil salinity. We tested this hypothesis via light microscopy of plant tissues to observe cell tonicity under different concentrations of saline solution. soil salinity was measured using saturated extraction. The results of this experiment show that most cells within the “bulb” structures were isotonic at a concentration approximately twice as high as that of root tissue and ambient soil salinity, therefore supporting the presented hypothesis.

Relationship between Photosynthetic Characteristics, Anatomical Structure, and Physiological Indexes of Two Halophytes in Different Habitats

Drought and salinity are considered to be the major limiting factors for plant growth in desert areas. Halophytes can maintain their growth in extreme salt environments. However, few studies have linked the photosynthetic characteristics of halophytes with their anatomical structures and leaf water potential to jointly explain the effects of drought and salt on leaf internal water use efficiency (WUEi). For this reason, two different halophytes, Nitraria sibirica and Alhagi sparsifolia, were selected to analyze the leaf physiological traits in response to different water and salt gradients. The analysis further revealed the influence of soil water and salt content and anatomical characteristics on plant photosynthesis. The results showed that the leaf water potential, morphology, anatomical parameters, and photosynthetic parameters of the two plants in different habitats showed significant species-specific physiological responses. The value of WUEi of N. sibirica was negatively correlated with net photosynthetic rate (Pn), stomatal conductance (Gs), tightness of palisade tissue (CTR), and soil factors, while the WUEi of A. sparsifolia was positively correlated with Pn, Gs, and CTR. The indirect effects of soil salinity and soil moisture on WUEi were also found to be species-specific. This study will help to improve the understanding of the ecological adaptability of plants to water and salt stress and provide a theoretical basis for clarifying the drought tolerance and salt tolerance adaptation strategies of halophytes in arid areas.

ACC Deaminase Produced by PGPR Mitigates the Adverse Effect of Osmotic and Salinity Stresses in Pisum sativum through Modulating the Antioxidants Activities.

Salinity-induced ethylene production and reactive oxygen species (ROS) inhibit agricultural productivity. The plant synthesizes ethylene directly from aminocyclopropane-1-carboxylic acid (ACC). By using ACC as a nitrogen source, bacteria with ACC deaminase (ACCD) inhibit the overproduction of ethylene, thereby maintaining the ROS. The present study investigated the ACCD activity of previously identified rhizobacterial strains in Dworkin and Foster (DF) minimal salt media supplemented with 5 mM ACC (as N-source). Bacterial isolates GKP KS2_7 (Pseudomonas aeruginosa) and MBD 133 (Bacillus subtilis) could degrade ACC into α-ketobutyrate, exhibiting ACCD activity producing more than ~257 nmol of α-ketobutyrate mg protein−1 h−1, and were evaluated for other plant growth-promoting (PGP) traits including indole acetic acid production (>63 µg/mL), phosphate solubilization (>86 µg mL−1), siderophore (>20%) ammonia and exopolysaccharide production. Furthermore, Fourier Transform Infrared analysis also demonstrated α-ketobutyrate liberation from ACC deamination in DF minimal salt media, thereby confirming the ACCD activity. These isolates also showed enhanced tolerance to salinity stress of 3% w/v NaCl in vitro, in addition to facilitating multifarious PGP activities. Seed bacterization by these ACCD-producing bacterial isolates (GKP KS2_7 and MBD 133) revealed a significant decline in stress-stimulated ethylene levels and its associated growth inhibition during seedling germination. They also mitigated the negative effects of salt stress and increased the root-shoot length, fresh and dry weight of root and shoot, root-shoot biomass, total sugar, protein, reducing sugar, chlorophyll content, and antioxidants enzymes in Pisum sativum. As a result, these strains (GKP KS2_7 and MBD 133) might be applied as biofertilizers to counteract the negative effects of soil salinity.

Root morphological and anatomical responses to increasing phosphorus concentration of wheat plants grown under salinity

Understanding the role of nutrients in the alleviation of salt stress effects and the unrevealed significance of root system architecture for plant adaptation is one of the major research areas in the current context of agriculture. Root anatomy is also a valuable parameter to be considered in understanding how the root system counters soil salinity's effect on plant growth. Although Root Phosphorus Acquisition Efficiency (RPAE) under salt stress differs depending on plant species and the severity of salinity in the rhizosphere, optimising phosphorus (P) nutrition seems to bring positive results. This study was planned to investigate the combined effect of salinity and P-availability on root morphology and anatomy as well as nutrient uptake of wheat plants. A pot experiment was performed in open-field conditions using a Moroccan variety of durum wheat. Special emphasis was placed on how orthophosphate and polyphosphate fertilizer forms and phosphorus doses alter the morphology and anatomy of the roots under salt stress. Two soluble fertilizers were used: an orthophosphate (Ortho-A) and a polyphosphate (Poly-B) were applied at four P levels (0, 30, 45 and 60 ppm of P). Our findings showed that salt stress induced, at both anatomical and morphological levels, a series of modifications in the roots of wheat plants. Compared to salt-stressed and unfertilized plants, soluble P-fertilizers significantly increased soil available P, root P- content, RPAE, root length (RL), root surface area (RSA), root volume (RV), root mass density (RMD), root tissue water content (TWC), number of root tips, vascular cylinder diameter and SD/CT ratio. Furthermore, Poly-B showed a positive response in both morphological and anatomical parameters at lower doses while Ortho-A revealed significant results within the increase in P-concentration. The increased root parameters observed under P-treatments could determine the root performance and efficiency to acquire water and P and their transport to the aboveground organs of wheat plants under salinity.

Osmotic adjustment of tomato under mild soil salinity can enhance drought resistance

Osmotic adjustment is an important mechanism for plants to withstand osmotic stress. The accumulation of Na+ can improve the osmotic adjustment of plants and enhance the ability of plants to withstand osmotic stress. However, the Na+ accumulation, osmotic stress, ion toxicity and oxidative damage of plants have not been fully explored under combined water and salt stress. The objectives of this study were to explore the effect of soil salinity on the drought tolerance of tomato. We set up four soil salinity treatments and three water treatments in 2019 and four soil salinity treatments and four water treatments in 2020. The salt was evenly mixed into the soil before the soil was filled into the growing area, and water treatment was carried out during the reproductive growth stage. Both water deficit and soil salinity reduced the dry matter accumulation of plants, but the interaction effect of water deficit and soil salinity on dry matter accumulation was less than that of single water stress when salt was added to the soil at 3 g/Kg dry soil. When water deficit was conducted, soil salinity enhanced osmotic adjustment more than aggravates osmotic stress. When the Na+ concentration in the leaves was lower than 100 mmol/L, the Na+ had little effect on the K+ concentration. Furthermore, mild and moderate water deficit did not lead to further increases malondialdehyde content in leaves under mild soil salinity (salt was added to the soil at 3 g/Kg dry soil). When leaf Na+ concentration was lower than concentration threshold (100–120 mmol/L in this study), osmotic adjustment was significantly enhanced, but there was no further significant influence on ion balance and oxidative damage, which effectively improved the drought resistance of tomato. Therefore, mild soil salinity may improve tomato yield under water deficit.

Modeling impacts of drought-induced salinity intrusion on carbon dynamics in tidal freshwater forested wetlands.

Tidal freshwater forested wetlands (TFFW) provide critical ecosystem services including an essential habitat for a variety of wildlife species and significant carbon sinks for atmospheric carbon dioxide. However, large uncertainties remain concerning the impacts of climate change on the magnitude and variability of carbon fluxes and storage across a range of TFFW. In this study, we developed a process-driven Tidal Freshwater Wetlands DeNitrification-DeComposition model (TFW-DNDC) that has integrated new features, such as soil salinity effects on plant productivity and soil organic matter decomposition to explore carbon dynamics in the TFFW in response to drought-induced saltwater intrusion. Eight sites along the floodplains of the Waccamaw River (USA) and the Savannah River (USA) were selected to represent the TFFW transition from healthy to moderately and highly salt-impacted forests, and eventually to oligohaline marshes. The TFW-DNDC was calibrated and validated using field observed annual litterfall, stem growth, root growth, soil heterotrophic respiration, and soil organic carbon storage. Analyses indicate that plant productivity and soil carbon sequestration in TFFW could change substantially in response to increased soil pore water salinity and reduced soil water table due to drought, but in interactive ways dependent on the river simulated. These responses are variable due to nonlinear relationships between carbon cycling processes and environmental drivers. Plant productivity, plant respiration, soil organic carbon sequestration rate, and storage in the highly salt-impacted forest sites decreased significantly under drought conditions compared with normal conditions. Considering the high likelihood of healthy and moderately salt-impacted forests becoming highly salt-impacted forests under future climate change and sea-level rise, it is very likely that the TFFW will lose their capacity as carbon sinks without up-slope migration.

Identification and characterization of salt-responsive proteins in mango (Mangifera indica L.)

Increasing salinity is a cause of concern for meeting UN sustainable development goals and needs urgent mitigation strategies. The widespread use of salinity tolerant rootstocks in salt-sensitive fruits provides long-term solutions to the harsh effects of soil salinization. Polyembryonic mango cultivar 13-1, a salinity-tolerant variety from Israel, was used to unravel initial salt adaptive mechanism by imposing a salinity screen at 200mM NaCl. Differentially accumulated proteins were separated through 2-D electrophoresis (pH gradient 4.0-7.0), and identified through properties of pI and molecular weight by annotation against Citrus isoelectric focusing database. Protein spots (309) were detected on Coomassie-stained gels and about 22 spots were found differentially expressed in control and stress. Overproduction of stress-related proteins like polygalacturonase (97 kDa/4.9PI) and alcohol dehydrogenase (38kDa/5.6PI) is linked to enhanced cell wall integrity, transpiration rate regulation and ionic maintenance in adaptability mechanism. The upregulated phenylpropanoid pathway proteins p-coumaroyl ester, Flavanone3-hydroxylase-2 and UDP-glycosyl transferase are also involved in stress alleviation through flavonoid accumulation. Glutathione S-transferase was also identified with 2.21-fold accumulation in plants exposed to salinity stress, thereby elucidating its role in oxidative stress mitigation. Cell wall and cytoskeleton metabolism-related proteins were also found to be associated with salinity adaptation in mango cv 13-1. Differential accumulation of proteins implicated in signal transduction pathway, transcription regulation and hormone signaling were also identified. Thus, role of differentially expressed proteins under initial salinity stress conditions provide new insights molecular adjustment mechanisms orchestrated by mango rootstock variety by hormone signaling, osmotic arrangements, cytoskeleton modifications, phenol accumulation and transcription regulation.

Effects of soil salinity on nutritional compositions of fresh Jak (Nypa fruticans) sap

The nutritional compositions of fresh Jak (Nypa fruticans) sap grown in mangrove environments with varying soil salinities were examined between sap from non saline (ECe < 2 dS/m), moderately saline (ECe = 4–8 dS/m), and saline soil (ECe = 8–16 dS/m). In saline sites, sap significantly (p < 0.05) increased in total soluble solids and sugar concentration. The total amino acid in the saline site was higher than in the other sites. The fresh Jak sap was rich in functional nutrients such as sugars (sucrose, glucose, fructose, starchyose, galactose, arabinose, maltose), organic acids (niacin, succinic, tartaric, malic, citric, lactic, acetic acids), minerals (P, K, Na, Ca, Mg, Al, Mn, Fe, Cu, Zn, Ni, B), essential amino acids (arginine, lysine, valine, histidine, threonine), seven non-essential amino acids (i.e. glutamic acid) and vitamins (B1, B3, B6, B12, E). Furthermore, potassium was significantly increased in salinity soil, and the decrease in potassium was associated with the increase in sodium. Fresh Jak sap from all salinity soils was shown to be an excellent source of several nutritional elements in this investigation. However, it appeared that Jak sap from the non saline site would be the best choice for use in the development of healthy food products.

Effects of deep softener and chemical compounds on mechanical compositions in heavy, difficult-to-ameliorate soils

The article deals with deep loosening of heavy, difficult-to-ameliorate, gypsum, medium salinity soils in the conditions of Bukhara region, as well as high-quality saline washing and watering of saline soils using a chemical reclamation (Spersal) compound. Significant water savings were observed during the harvest, and the control of dry residue and chlorine ions was reduced in the remaining variants, in addition the results of the study to the effect of the Bukhara-102 variety of cotton on the amount of salts in the soil by irrigating are presented. In this case, the cotton is cultivated without deep loosening of the soil with the variant of direct cultivation of the soil with a deep softener, softening at a depth of 60 cm and 80 cm, and irrigation of the (Spersal) compound, drainage, the effect of soil salinity on fertility and water permeability was analyzed.

Impacts of osmopriming on mitigation of the negative effects of salinity and water stress in seed germination of the aromatic plant Lavandula stoechas L.

Butterfly lavander (Lavandula stoechas L.) seed germination is sensitive to salinity and water stress. Seed priming effectively mitigates the adverse effects of salt and water stresses on seed emergence. Although its extensive uses as an ornamental plant, no studies have assessed the effects of seed priming on Butterfly lavander germination under salinity and moisture stress. Here, we investigate whether KCl-osmopriming could improve germination fitness of L. stoechas under salt and watre stresses. Seeds of this species were osmoprimed with different levels of KCl (1 %, 2 %, and 4 %) and germinated in different concentrations of NaCl (0, 50, 100, 150 mM) and water deficit (0, −0.25, −0.5, −0.75, and −1.0 MPa PEG). Non-treated seeds (control) had little dormancy; around 90 % of the seeds were germinated. The germination was significantly decreased with the increase in salinity and water deficit stress. However, seed osmopriming markedly increased the germination percentage and rate in higher salinity and lower water potential levels.The impact of osmopriming was more obvious under the high-stress condition (i.e., higher salinity and lower water potential) than at the less-stress conditions. In addition, hydrotime model analysis indicated that seeds primed with 4 % KCl showed increasing germination rate (decreased θH) and uniformity (decreased σψb) under water deficiency. These results indicate that the application of KCl-osmopriming could alleviate the harmful effects of soil salinity and water stress on seed germination, suggesting that these treatments would enhance L. stoechas establishment in arid and semi-arid bioclimates.

Amelioration of harmful effects of soil salinity on plants through silicon application: a review

Amelioration of harmful effects of soil salinity on plants through silicon application: a review

Microbial Community Composition and Activity in Saline Soils of Coastal Agro-Ecosystems.

Soil salinity is a serious problem for agriculture in coastal regions. Nevertheless, the effects of soil salinity on microbial community composition and their metabolic activities are far from clear. To improve such understanding, we studied microbial diversity, community composition, and potential metabolic activity of agricultural soils covering non–, mild–, and severe–salinity. The results showed that salinity had no significant effect on bacterial richness; however, it was the major driver of a shift in bacterial community composition and it significantly reduced microbial activity. Abundant and diverse of microbial communities were detected in the severe–salinity soils with an enriched population of salt–tolerant species. Co–occurrence network analysis revealed stronger dependencies between species associated with severe salinity soils. Results of microcalorimetric technology indicated that, after glucose amendment, there was no significant difference in microbial potential activity among soils with the three salinity levels. Although the salt prolonged the lag time of microbial communities, the activated microorganisms had a higher growth rate. In conclusion, salinity shapes soil microbial community composition and reduces microbial activity. An addition of labile organic amendments can greatly alleviate salt restrictions on microbial activity, which provides new insight for enhancing microbial ecological functions in salt–affected soils.

The effect of soil salinity and pepino mosaic virus infection on the expression of tomato defence‐related genes

AbstractTo reflect field conditions where cultivated plants are frequently exposed to multiple stresses simultaneously, the effect of salinity on the expression of defence‐related genes in tomato plants was examined in the absence and presence of pepino mosaic virus (PepMV) infection. Tomato seedlings were grown under three soil salinity regimes from the fourth day after transplantation: (a) no‐added salt (control), (b) low salinity (20 mM NaCl) and (c) high salinity (100 mM NaCl). The plants were non‐, mock‐ or PepMV‐inoculated 14 days after transplantation and systemic leaves were collected 4 days postinoculation for analysis by reverse transcription‐quantitative PCR (RT‐qPCR). In noninoculated tomato plants exposed to low and high salinity, expression of the salicylic acid (SA)‐, jasmonic acid‐, ethylene‐related genes was typically down‐regulated compared to control plants, with only a slight (nonsignificant) increase in ABA2 expression. In PepMV‐infected tomato plants, a strong induction of SA‐related genes was observed, which was compromised under low and high salt stress. The induction of PR1 gene expression by PepMV infection was the highest (an 82‐fold increase) in control plants, but was significantly less (a 20‐fold increase) under conditions of low and high soil salinity. No direct correlation between SA gene expression levels and PepMV RNA accumulation became apparent. In RT‐qPCR, the levels of PepMV genomic RNA and tomato LoxD and ACS1 RNA transcripts under mild salt stress were significantly reduced (the former 6‐fold), but under high salt stress the levels of all were similar to those in the nonstressed controls.