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Salinity is one of the most brutal environmental factors limiting the productivity of crop plants because most of the crop plants are sensitive to salinity caused by high concentrations of salts in the soil, and the area of land affected by it is increasing day by day. High soil salinity causes osmotic stress, nutritional imbalance, and ion toxicity to plants and severely affects crop productivity in farming systems. The salinization of soil is causing a decrease in farmland agriculture as the world's population rises day by day, endangering the availability of food. There are soils affected by salt all throughout the world, particularly in dry and semi-arid areas. For sustainable crop production, salt-stressed soils need to be corrected and managed in a proper way. Compared to chemical and physical methods, bioremediation is more environmental friendly method for correcting salt affected soils. The use of halophilic bacteria has been found to be an effective approach for plant promotion under salt-stress conditions. They help in enhancing the soil health and the yield of crop in salt-affected soils. This review will focus on the revitalizing the salt affected soils by using halophilic bacteria and their mechanisms in the soil and interaction with the plants. [ABSTRACT FROM AUTHOR]

In this research study, we investigated four strains of Enterobacter ludwigii that showed promising properties for plant growth. These strains were tested for their ability to mobilize phosphorus and produce ammonium, siderophores, and phytohormones. The strains exhibited different values of PGP traits; however, the analysis of the complete genomes failed to reveal any significant differences in known genes associated with the expression of beneficial plant traits. One of the strains, GMG_278, demonstrated the best potential for promoting wheat growth in pot experiments. All morphological parameters of wheat were improved, both when GMG_278 was applied alone and when combined with mineral fertilizer. The combined effect we observed may suggest various mechanisms through which these treatments influence plants. The amount of pigments and proline suggests that bacterial introduction operates through pathways likely related to stress resilience. A study on the genetic mechanisms behind plant resilience to stress has revealed a significant upregulation of genes related to reactive oxygen species (ROS) defense after bacterial exposure. It is important to note that, in the initial experiments, the strain showed a significant production of salicylic acid, which is a potent inducer of oxidative stress. In addition, the synthesis of some phytohormones has been restructured, which may affect root growth and the architecture of root hairs. When combined with additional mineral fertilizers, these changes result in a significant increase in plant biomass. [ABSTRACT FROM AUTHOR]

Although organic amendment has been widely demonstrated to be capable of reassembling soil microbiomes in coastal salt-affected soils, quantitative characterization in respect to how abiotic and biotic components drive the diversifications of soil microbial community and function remains rudimentary. We investigated the effects of types and application rates of different exogenous organic ameliorants (sewage sludge, S; vermicompost, V) on the physicochemical properties, fungal community diversity, and fungal functional traits in coastal salt-affected soils. Results revealed that both S and V amendments exhibited significantly positive impacts on the alleviation of environmental constraints and the reassembly of fungal community and functional profile. Of note, efficacy of the two exogenous organic ameliorants was significantly influenced by the types of carbon sources utilized and the rates at which they are applied. More pronounced variations in soil physicochemical and microbiological properties were observed in soils amended by S and V at the application rate of 200 t ha−1. Both S and V treatments positively boosted soil fungal community diversification with higher compositional diversities found in the majority of amended soils when compared to unamended soils. In addition, S and V applications favored the flourishment of functions linked to saprotrophic strategy with soil saprotrophs and wood saprotrophs predominating the functional profiles in soils amended by S and V, respectively. Results obtained from redundancy analysis and structural equation modeling revealed that pH, salinity, and SOC were the principle edaphic factors that significantly and directly affected the reassembly of fungal community. In addition, fluctuations in the prevalence of specific fungal genera, including Stachybotrys, Trichoderma, Mortierella, and Acremonium, emerged as a decisive biotic factor influencing diversifications of fungal communities and functional profiles. Taken together, this study not only highlighted the efficacy of S and V application on environmental constraints alleviation in coastal mudflats, but also qualitatively identified and quantitatively illustrated potential pathways and effectiveness of edaphic and biotic components driving the diversification of soil fungal microbiomes and functional profiles. These findings would enhance our understanding in respect to the microbial-mediated amelioration process of salt-affected soils within coastal mudflat ecosystem. [ABSTRACT FROM AUTHOR]

Remote sensing of stressor action on plants is an important step of their protection. Measurement of photochemical reflectance index (PRI) can be used to detect action of stressors including salinization; potentially, a small-scale spatial heterogeneity of PRI (within leaf or its part) can be an indicator of this action. The current work was devoted to analysis of sensitivity of the small-scale heterogeneity in PRI and in the reflected light intensity at 530 nm (approximately corresponding to the measuring wavelength for PRI) in leaves of pea (Pisum sativum) plants to action of salinization. Plants were cultivated under controlled conditions of a vegetation room and under open-air conditions. It was shown that both the standard deviation of PRI and coefficient of variation of the reflected light intensity at 530 nm were sensitive to action of salinization on plants. Moreover, this variation coefficient was negatively corelated to the potential quantum yield of PSII; i.e. increasing the coefficient could be used to estimate decreasing this yield caused by photodamage of PSII under salinization. Our results show that the small-scale spatial heterogeneity in PRI and the reflected light intensity at 530 nm can be used as additional tools of the remote sensing of plant responses under action of salinization. Remote sensing of action of stressors on plants is an important step of their protection. We showed that action of salinization stimulated spatial heterogeneity in the photochemical reflectance index, which was calculated on basis of the leaf reflectance at 530 and 575 nm, and in reflectance at 530 nm in pea (Pisum sativum) leaves. It means that measurements of the spatial heterogeneity of these parameters can be used as indicator of the action of salinization in the plant remote sensing. [ABSTRACT FROM AUTHOR]

Coastal ecosystems face salinization and rising temperatures. In coastal ectotherms, salinity and temperature affect metabolism, tolerance, infections, growth, behavior, and survival. Overall, the combined effects of salinity and temperature on species distribution, community structure, invasive species, and ecosystem functioning need to be fully assessed to understand impacts from these stressors. [ABSTRACT FROM AUTHOR]

Freshwater salinization is an increasing threat to lakes worldwide, but despite being a widespread issue, little is known about its impact on biological communities at the base of the food chain.Here we used a mesocosm set‐up coupled with modern high‐frequency sensor technology to identify short‐ and longer‐term responses of phytoplankton to salinization in an oligotrophic lake. We tested the effects of salinization over a gradient of increasing salt concentrations that can be found in natural lakes exposed to road salt contamination (added salt range: from 0 to 1500 mg Cl− L−1).The high‐frequency chlorophyll‐a (chl‐a) fluorescence measurements showed an increasing divergence of chl‐a concentrations along the salinization gradient over time, with substantially lower concentrations at higher salt levels. At the sub‐daily scale, we found a profound suppression of day–night signal cycles with increasing salinity, which could be related to physiological stress due to the impairment of photosynthesis via effects on the photosystem II or potential changes in the active migration of phytoplankton. Community analyses revealed a similar decline pattern for the total phytoplankton biomass and a collapse of the total zooplankton biomass. Interestingly, we found a loss of phytoplankton diversity coupled with a compositional re‐organization involving the loss of dominant green algae but increased biomass of salt‐tolerant cyanobacteria.Altogether, these results suggest that specific cyanobacterial taxa can benefit from freshwater salinization following the collapse of dominant phytoplankton competitors and zooplankton herbivores. The results also highlight the value of autonomous sensor technology to capture novel, small‐scale ecological responses to freshwater salinization, and thereby to track fast changes in primary producer communities. [ABSTRACT FROM AUTHOR]

Previous studies have shown that there are significant sexual differences in the physiological responses of Torreya grandis to environmental stress. However, little is known about its sex-specific differences in response to salt stress against the background of nitrogen (N) deposition. In this experiment, two-year-old male and female T. grandis seedlings were used as experimental materials and exposed to moderate salt conditions and different N levels to study the effects of nitrogen addition and salt stress on the chlorophyll content, chlorophyll fluorescence parameters, antioxidant system, and leaf stoichiometry of T. grandis seedlings. With the increase in nitrogen content, the contents of proline, malondialdehyde, superoxide anion, and H2O2 in the leaves of T. grandis seedlings under salt conditions gradually increased. The contents of these four metabolites in the leaves of male T. grandis seedlings were almost all higher than those of the female ones. Compared with the control group, the contents of enzymatic and non-enzymatic antioxidants increased under N addition treatments, especially for the low and moderate N addition groups. The results showed that moderate concentrations of N addition can mitigate the damage caused by salt, while high concentrations of nitrogen do not. Under conditions of salt and nitrogen addition, female T. grandis seedlings outperformed male ones, as evidenced by their higher photosynthetic pigment content, enhanced antioxidant enzyme activity, reduced accumulation of intracellular cytotoxic metabolites, and higher carbon and nitrogen content in their leaves compared to those of male seedlings. The findings of this research will contribute to our understanding and offer a theoretical foundation for the cultivation of T. grandis seedlings in environments with nitrogen deposition and salinization. [ABSTRACT FROM AUTHOR]

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

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

Widely represented in many arid regions of the world, dry marshes pose a potential threat to the adjacent areas because of soil salinization caused by wind transfer (for long distances) of toxic mineral salts from the dried surface. For environmental monitoring of such soils, remote microwave sensing methods are used. In this work, we study at a 2.3 cm wavelength the summer diurnal dynamics of microwave radiation of sodic solonchak formed on the dried bottom of a hypersaline lake. It has been established that the study indicator (in the centimetre range) depends on the cumulative changes in temperature, moisture and salinity of soils. With rise in soil temperature, intensive evaporation and topsoil drying, a salt crust and the underlying layer with less moisture (accompanied by microwave radiation interference on the layered structure of solonchak) can be formed. In the experiment, a daily variation in the brightness temperature of the study object (a specific object) by 25 K occurred with change in thermodynamic temperature of the skin layer by 10 K. [ABSTRACT FROM AUTHOR]

The analysis of the characteristic and mechanism of water-salt migration in farmland soil plays an important role in the whole crop growth process, and is an important reference for irrigation decision-making, salinization control and crop yield improvement. We analyzed the relevant literatures on water and salt migration retrieved from CNKI and Web of Science from 1973 to 2023, used CiteSpace software to conduct a visual analysis of the relevant literatures, and summarized the current research focus and future development trend of water and salt migration. Visual quantitative analysis of the number of articles published in the field of soil water and salt migration at home and abroad in the past 50 years was adopted, including the number of authors and institutions, the co-occurrence of keywords, clustering and emergence timeline maps. Results showed that the topic heat of water and salt migration continued to increase. The authors of domestic articles were closely related to each other, and the core research team in the field of water and salt migration was gradually expanding. The domestic publishing institutions had a strong influence in the field of water and salt migration research, among which the research of the Chinese Academy of Sciences made a significant contribution, but the research had regional limitations. The research content of soil water and salt migration mainly focused on the change law of water and salt content in soil, plant drip irrigation technology and its simulation prediction. The study of soil water and salt migration was of great significance to the treatment of large area of saline-alkali land in China. Meanwhile, the different conditions of water and salt migration in different regions also became the focus of future research. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTPlants face numerous environmental challenges from biotic and abiotic stressors, with soil salinization emerging as a significant global concern. The coastal regions of Tamil Nadu, face severe environmental challenges due to discharge of saline water from shrimp farms exacerbates this issue, compromising the viability of paddy and other crops in the vicinity. This study explores the phytoremediation potential of Suaeda fruticosa in addressing soil salinity resulting from shrimp farming activities under field conditions over a 120-day period to restore soil health in salt affected soil. This research demonstrates Suaeda fruticosa’s exceptional salt tolerance and bioaccumulation potential in facilitating soil restoration. Significant enhancements were observed in various growth parameters, including 466% increase in plant height, 338% in fresh weight and 387% in dry weight. Biochemical parameters also showed substantial enhancements with total chlorophyll, protein, proline, phenol, and glycinebetaine levels increasing by 655%, 588%, 690%, 153%, and 531%, respectively. Enzymatic activities exhibited notable elevations as well, with catalase, peroxidase, and polyphenol oxidase activities escalating by 258%, 587%, and 121% respectively, indicating robust adaptation to saline environments. Moreover, Suaeda fruticosa exhibited remarkable bioaccumulation capabilities, accumulating 461 kg NaCl ha−1. This led to substantial improvements in soil characteristics, including a reduction in pH from 8.8 to 6.49, electrical conductivity from 5.7 to 1.53 dSm−1, and sodium adsorption ratio from 16.1 to 4.4 mmol L−1. The successive cultivation of Suaeda fruticosa in this study, has proven to be a viable strategy for reclaiming salt-affected lands, thereby alleviating a significant constraint on crop productivity.In this phytoremediation study, Suaeda fruticosa can effectively bioaccumulate considerable amounts of NaCl from the soil, leading to marked improvements in soil quality. This includes reductions in soil pH, electrical conductivity, and sodium adsorption ratio. A salt marsh halophyte, Suaeda fruticosa not only accumulates salt but also adapts to such conditions by synthesizing substantial amounts of organic solutes and enhancing its antioxidant machinery to mitigate toxicity induced by ionic stress. This research underscores a promising and sustainable approach for the reclamation of saline-affected agricultural soils, offering a viable solution to enhance crop productivity in coastal regions impacted by shrimp aquaculture. [ABSTRACT FROM AUTHOR]

The blue tilapia Oreochromis aureus is a native afro-tropical cichlid that occurs in Morocco. In the intermittent rivers and ephemeral streams (IRES), this species has been facing multiple environmental stressors, particularly flow intermittence and salinization that may affect their life-history traits. The current study addressed two relict sub-Saharan populations of O. aureus in the Draa basin, SE Morocco, from the permanent saline Tissint River and an intermittent highly salinized reach of the Draa River at Sidi El Mokhtar. Captured tilapias were weighed and measured for body length. Scaled-mass index (SMi) was calculated to assess body condition. Based on body length and scalimetry-determined age, von Bertalanffy growth parameters were estimated in addition to length and age at maturity, mortality rate and longevity using empirical relations. Fish were much smaller, lighter and in poorer condition in the intermittent salinized stream than in the permanent saline Tissint River. The asymptotic length was half, but the growth constant rate was double, with rather a lower growth performance compared to Tissint. Sexual maturation occurred earlier at a much smaller body length. The mortality rate was twice that observed in Tissint, and the estimated longevity was three times shorter. Overall, O. aureus adapts to the extreme conditions of flow intermittence and salinization in the Draa basin by exhibiting fast growth and earlier maturation, which likely contribute to higher fecundity and recruitment. These traits help compensate for the increased mortality rate and shorter longevity associated with these challenging conditions. Such information would be useful for conservation and management of these relict tilapias and their habitat. Moreover, fish farming can be potentially developed in the permanent flowing brackish waters. [ABSTRACT FROM AUTHOR]

The jiandiping 尖底瓶 amphora is a distinctive pottery type of the Yangshao culture (5000 − 3000 BCE), predominantly found along the middle course of the Yellow River, with a significant concentration in the Wei River Valley. Despite its widespread presence, the function of this vessel has remained elusive in scholarly discourse. This article investigates the amphora's spatial relationship to salt deposits and examines its physical characteristics, evaluating these aspects within the context of the Yangshao population's lifestyle in the Wei River Valley. By incorporating evidence from Shang dynasty oracle bone inscriptions and various ethnoarchaeological studies, we propose a new interpretation of the jiandiping amphora as a tool for salt processing. This study prompts a reevaluation of Neolithic cultural and technological practices, highlighting the Yangshao society's potential involvement in salt exploitation in the Wei River Valley. [ABSTRACT FROM AUTHOR]

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

The El Haouz and El Kelaa Des Sraghna region is renowned for its agriculture, but is facing problems of salinisation due to its arid climate and unfavourable weather conditions. To remedy this, localised irrigation systems have been introduced to provide water for crops and improve yields. This study examines the impact of these irrigation systems on soil salinity in the region by comparing upstream and downstream areas. Using remote sensing techniques, we identify areas at risk of high salinity and collect soil samples for physical and chemical analysis in the field. These analyses enable us to monitor changes in salinisation and assess the effectiveness of localised irrigation in the areas concerned. Our results reveal two distinct zones in the region: an upstream zone with low salinity, with electrical conductivity ranging from 66 µS/cm to 345 µS/cm, and a downstream zone with higher salinity, with electrical conductivity ranging from 228 µS/cm to 1.075 µS/cm, attributed to the use of localised irrigation for crops. The remote sensing maps anticipated this difference, which was confirmed by the field analyses. [ABSTRACT FROM AUTHOR]

The increasing installation of shrimp farms in vulnerable coastal areas around the world generates an environmental impact and makes it urgent to develop methodologies and studies for assessing and scaling the potential risks and sustainability of these activities. One of the main hazards of these activities is that the prolonged inundation of excavated ponds for shrimp farming allows the percolation of saltwater in the surroundings, resulting in increasing groundwater salinity. Saltwater intrusion in coastal aquifers, accompanied by salinization of soils, causes a decrease in available freshwater resources, a decline in crop productivity and the deterioration of the natural ecosystem. The coastal aquifer of Rio Grande do Norte State (Brazil) where, for years, several shrimp farm factories have been operating, reported some issues related to aquifer and soil salinization. The present study aims to assess the origin of and delineate groundwater salinization in a sector of this coastal aquifer using a low-budget procedure. The integration of hydrogeological and hydrogeochemical characterization by drilling shallow piezometers, measuring the hydrostatic level and analyzing the major ion concentrations of the groundwater has made it possible to establish that the origin of groundwater pollution in the studied area is caused by saltwater percolation from shrimp farms. The joint use of both characterization techniques has been shown to have an efficient cost–benefit ratio and less-intrusive methodology, which can be applied in other areas with similar environmental concerns. [ABSTRACT FROM AUTHOR]

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

BACKGROUND AND OBJECTIVES: Cirebon City, located in West Java, Indonesia, is one of the coastal cities formed from alluvial deposits with aquifer rocks in form of gravels and sands in the plains, as well as sands in the hills. Due to its urbanized nature, the city experiences a substantial need for access to clean water. A significant number of residents remain reliant on drinking water providers for safe water, given the contamination of seawater in specific regions, while some continue to draw from shallow groundwater. As groundwater abstraction can intensify seawater intrusion, especially in urbanized area, it is important to investigate this matter. This study sought to qualitatively and quantitatively analyze the degree of seawater pollution affecting the shallow groundwater in Cirebon City, Indonesia.METHODS: Water samples were collected from 44 shallow groundwater wells around Cirebon City. Following collection, the samples were examined for their significant water chemistry content using ion chromatography and for their isotopic composition through a liquid water isotope analyzer. Interpretation was done using graphical tools such as Piper and scatter diagrams, as well as mathematical equation to approximate mixing proportion between fresh groundwater and seawater and its proportion.FINDINGS: Stable isotope analysis revealed that eight shallow groundwater samples were salinized due to the incorporation of seawater, with the proportion of seawater ranging from approximately 17.3 to 54.9 percent. These samples have very enriched oxygen-18 isotope composition values up to -3.9 permil. Another 14 samples were mixed with surface water, and the remaining 22 samples were fresh groundwater. Analysis of the hydrochemical properties indicates that fresh shallow groundwater primarily exhibits a bicarbonate composition. In contrast, the salinized shallow groundwater is identified as sodium chloride type, with chloride concentrations reaching a maximum of 6980 milligrams per liter and sodium concentrations peaking at 4963 miligrams per liter. Salinized shallow groundwater samples were up to 1.5 kilometer inland from coastline, which can be considered as an environmental concern.CONCLUSION: The seawater contamination into shallow aquifer have reached up to 1.5 kilometer inland and with seawater proportion is up to 55 percent. Throughout the contamination process, the chemical composition of groundwater is modified not solely due to mixing, but also as a result of ion-exchange mechanisms. The significant rate of seawater contamination necessitates urgent action from all stakeholders, with local government leadership being essential. To effectively address this problem, it is vital to limit the extraction of shallow groundwater by enhancing the capabilities of the government’s water piping services and to either slow down or completely halt the advancement of seawater intrusion through the adoption of artificial groundwater recharge strategies.

Objectives: The problem of salinity is considered as one of the main problems that soil is facing in the countryside of Al-Amiriya district, as it is located within the dry and semi-dry region. The main aim of this research is to investigate the role of human factors and to explain its impacts on the spread of the phenomenon of salinity among the study area. It also aimed to investigate its impact on agricultural production.Methodology: The research relied on the regional and analytical-descriptive approach in order to provide the required data in addition to field work.Results: The analysis of the data showed that neglecting drainage projects and burying many of them in the study area negatively affected agricultural production. The results also showed that unregulated irrigation was one of the important reasons that could lead to the exacerbation of the problem of salinity.Conclusion: The study concluded that the area suffers from severe salinization in many parts of it. The reason for this salinization is the high temperatures and the increased rate of evaporation. In addition, the poor management of land and water by humans was considered as one of the risky factors of salinity. Other factors could affect the area of the study such as, wrong methods of tilling and leveling the soil at inappropriate times and the expansion of summer agriculture. All after mentioned factors could have a direct impact on soil salinity in the study area.

Groundwater salinization is a crucial socio-economic and environmental issue that is significant for a variety of reasons, including water quality and availability, agricultural productivity, health implications, socio-political stability and environmental sustainability. Salinization degrades the quality of water, rendering it unfit for human consumption and increasing the demand for costly desalination treatments. Consequently, there is a need to find simple, sustainable, green and cost-effective methods that can be used in understanding and minimizing groundwater salinization. Therefore, this work employed the implementation of cost-effective neurocomputing approaches for modeling groundwater salinization. Before starting the modeling approach, correlation and sensitivity analyses of the independent and dependent variables were conducted. Hence, three different modeling schema groups (G1–G3) were subsequently developed based on the sensitivity analysis results. The obtained quantitative results illustrate that the G2 input grouping depicts a substantial performance compared to G1 and G3. Overall, the evidential neural network (EVNN), as a novel neurocomputing technique, demonstrates the highest performance accuracy, and has the capability of boosting the performance as against the classical robust linear regression (RLR) up to 46% and 46.4% in the calibration and validation stages, respectively. Both EVNN-G1 and EVNN-G2 present excellent performance metrics (RMSE ≈ 0, MAPE = 0, PCC = 1, R2 = 1), indicating a perfect prediction accuracy, while EVNN-G3 demonstrates a slightly lower performance than EVNN-G1 and EVNN-G2, but is still highly accurate (RMSE = 10.5351, MAPE = 0.1129, PCC = 0.9999, R2 = 0.9999). Lastly, various state-of-the-art visualizations, including a contour plot embedded with a response plot, a bump plot and a Taylor diagram, were used in illustrating the performance results of the models. [ABSTRACT FROM AUTHOR]

Due to their sessile lifestyle, plants need to optimize their growth in order to adapt to ever-changing environments. Plants receive stimuli from the environment and convert them into cellular responses. Brassinosteroids (BRs), as growth-promoting steroid hormones, play a significant role in the tradeoff between growth and environmental responses. Here, we provide a comprehensive summary for understanding the crosstalk between BR and various environmental stresses, including water availability, temperature fluctuations, salinization, nutrient deficiencies and diseases. We also highlight the bottlenecks that need to be addressed in future studies. Ultimately, we suppose to improve plant environmental adaptability and crop yield by excavating natural BR mutants or modifying BR signaling and its targets. [ABSTRACT FROM AUTHOR]

Groundwater plays a critical role in supporting a wide range of human activities. However, it faces substantial challenges due to the growing demand for water and reduced precipitation resulting from climate change. Various studies have revealed the high vulnerability of Morocco’s groundwater to contamination from multiple anthropogenic sources. This review focuses on assessing nitrate and salinization pollution in Moroccan groundwater, with a specific emphasis on the Gharb region. A comprehensive analysis of research conducted from 2010 to 2023, using reputable databases, underscores the pressing need to address groundwater pollution in Morocco, especially in the Gharb region. The results highlight the significant challenges faced by Morocco’s groundwater resources. Agricultural practices and poorly designed irrigation systems are identified as primary contributors to nitrate contamination. Additionally, salinization in the region is influenced by factors such as seawater intrusion, hydrogeological characteristics, and irrigation practices. An integrated approach, combining laboratory analysis, remote sensing, geospatial tools, modeling, and geographic information systems technology, has proven to be effective in addressing the complex issues of assessing groundwater pollution due to nitrate and salinization. This survey presents a comprehensive framework for future research and decision-making processes aimed at achieving sustainable water resource management, preserving the groundwater heritage and safeguarding public health. [ABSTRACT FROM AUTHOR]

Problem, research strategy, and findings: Sea-level rise will bring ocean salts inland and salinize the drinking water sources of some coastal communities. How are municipalities, regions, and states preparing for salinization? In this study I evaluated 264 climate plans and seven state water plans from the Atlantic and Gulf coasts of the United States. Of these, 65 climate adaptation plans engaged with salinization in the context of drinking water; 21 made salinity adaptation recommendations, 6 discussed implemented monitoring or modeling, and 11 discussed implemented adaptation strategies. In state water plans, some states showed considerable salinization adaptation activity, but not all linked these actions to climate adaptation. Despite seawater intrusion and salinization being widely recognized, actions were concentrated in fewer states. Maryland, Delaware, Virginia, Florida, and Texas exhibited high degrees of engagement. Louisiana, Mississippi, Alabama, and Georgia showed little evidence of planning for salinization in climate or state water plans. In the absence of federal or state governments leading on managing sea-level rise–driven salinization, evaluating and preparing for the challenge of salinization is likely to become the de facto responsibility of coastal water suppliers and well owners, who may not have the capacity, budget, or jurisdiction to adequately monitor and protect supplies. Takeaway for practice: Left to individual drinking water suppliers and well owners with varying capacity for adaptation, water supply salinization driven by sea-level rise has the potential to exacerbate existing inequities in drinking water provision. Planners can contribute to adapting coastal drinking water systems by integrating monitoring and modeling into climate adaptation plans, creating partnerships that enable drinking water adaptation actions, and supporting new approaches to water funding and financing. [ABSTRACT FROM AUTHOR]

The Salton Sea has experienced significant recession over the past two decades due to changes in the diversion of Colorado River water to the Salton Trough for agricultural irrigation. As a result, wetlands have emerged in some exposed playa areas along the Salton Sea, primarily in regions with extensive agricultural return flows and agricultural drainage. One notable wetland system, known as the Bombay Beach Wetlands, has formed on the north shore of the Salton Sea, in an area devoid of agriculture. In many other areas with limited or no agriculture, wetlands have failed to develop, leaving exposed playa surfaces as the Salton Sea recedes. These dry playa surfaces pose a significant threat to the health of local residents due to the presence of toxins contained in windblown dust associated with playa deposits. In this study, stable water isotope data, combined with other hydrological information, led to identification of two potential water sources for the Bombay Beach Wetlands. The first possibility proposes that thermal artesian waters alone contribute to the wetlands' water source, while the second hypothesis involves a combination of drainage from Salton Sea bank storage water mixing with the thermal artesian water. The thermal artesian water discharges into drainage channels that flow towards the Bombay Beach Wetlands, initially devoid of possible groundwater baseflow until reaching the wetlands. Studies were subsequently done along the full reach of the drainage channels receiving thermal artesian water. Dissolved solids content, P and N nutrients, arsenic, and stable water isotopes were tested synoptically along the drainage channels. Channel investigations led to the development of a novel model of salinization, which is linked to channel discharge, channel morphometrics, and channel incision. [ABSTRACT FROM AUTHOR]

This study focuses on detecting and mitigating soil salinization in four coastal areas of the Mekong Delta (Vietnam). Salinity patterns in the soils of the Mekong River Delta are not random but linked to land use practices and distance to the sea. We examine two quick yet reliable remote sensing-based techniques to detect the coastal aquaculture area and separate it from the inland freshwater farmland. These techniques can eventually be used to identify locations with an elevated risk of salinization in other coastal regions. Finally, we investigate a salinization mitigation solution based on creating a managed aquifer recharge system along the buffer zone that separates the coastal aquaculture area from the inland freshwater agriculture area. The implementation of an infiltration pond system is technically feasible in the Mekong Delta provided that hydrogeological characteristics, the fresh-saline interface position, and freshwater demands are considered. The transitional zone between freshwater agriculture and brackish water aquaculture in Bac Lieu, Soc Trang, Tra Vinh and Ben Tre provinces is optimal for implementing an aquifer recharge/freshwater barrier scheme. [ABSTRACT FROM AUTHOR]

Flooding and salinization triggered by storm surges threaten the survival of coastal forests. After a storm surge event, soil salinity can increase by evapotranspiration or decrease by rainfall dilution. Here we used a 1D hydrological model to study the combined effect of evapotranspiration and rainfall on coastal vegetated areas. Our results shed light on tree root uptake and salinity infiltration feedback as a function of soil characteristics. As evaporation increases from 0 to 2.5 mm/day, soil salinity reaches 80 ppt in both sandy and clay loam soils in the first 5 cm of soil depth. Transpiration instead involves the root zone located in the first 40 cm of depth, affecting salinization in a complex way. In sandy loam soils, storm surge events homogeneously salinize the root zone, while in clay loam soils salinization is stratified, partially affecting tree roots. Soil salinity stratification combined with low permeability maintain root uptakes in clay loam soils 4/5‐time higher with respect to sandy loam ones. When cumulative rainfall is larger than potential evapotranspiration ETp (ETp/Rainfall ratios lower than 1), dilution promotes fast recovery to pre‐storm soil salinity conditions, especially in sandy loam soils. Field data collected after two storm surge events support the results obtained. Electrical conductivity (a proxy for salinity) increases when the ratio ETp/Rainfall is around 1.76, while recovery occurs when the ratio is around 0.92. In future climate change scenarios with higher temperatures and storm‐surge frequency, coastal vegetation will be compromised, because of soil salinity values much higher than tolerable thresholds. Key Points: Evapotranspiration and rainfall affect post‐storm surge soil salinity in the root zone of coastal forestsIn clay loam soils, post‐storm surge salinity stratification is beneficial for root uptakeTime to recover to pre‐storm soil salinity values depends on evapotranspiration and rainfall ratios and soil properties [ABSTRACT FROM AUTHOR]

Saltwater intrusion (SWI) is a well‐studied phenomenon that threatens the freshwater supplies of coastal communities around the world. The development and advancement of numerical models has led to improved assessment of the risk of salinization. However, these studies often fail to include the impact of surface waters as potential sources of aquifer salinity and how they may impact SWI. Based on field‐collected data, we developed a regional, variable‐density groundwater model using SEAWAT for east Dover, Delaware. In this location, major users of groundwater from the surficial aquifer are the City of Dover and irrigation for agriculture. Our model includes salinized marshland and tidal streams, along with irrigation and municipal pumping wells. Model scenarios were run for 100 years and included changes in pumping rates and sea‐level rise (SLR). We examined how these drivers of SWI affect the extent and location of salinization in the surficial aquifer by evaluating differences in chloride concentration near surface waters and the subsurface freshwater‐saltwater interface. We found the presence of the marsh inverts the typical freshwater‐saltwater wedge interface and that the edge of the interface did not migrate farther inland. Additionally, we found that tidal streams are the dominant pathways of SWI at our site with salinization from streams being exacerbated by SLR. Our results also show that spatial distribution of pumping affects both the magnitude and extent of salinization, with an increase in concentrated pumping leading to more intensive salinization than a more widely distributed increase of the same total pumping volume. Key Points: Presence of a saltmarsh inverts the freshwater‐saltwater interface in our study locationTidal streams contribute substantially to salinization of inland groundwaterConcentrated pumping led to more intensive salinization than widespread pumping [ABSTRACT FROM AUTHOR]

Ecological zonation in coastal forests is driven by sea level rise and storm‐surge events. Mature trees that can survive moderately saline conditions show signs of stress when soil salinity increases above its tolerance levels. As leaf burn, foliar damage, and defoliation reduce tree canopy cover, light gaps form within the crown. At the forest‐marsh edge, canopy cover loss is most severe; trunks of dead trees without canopies form "ghost forests." Canopy thinning and light from the edge alter conditions for understory vegetation, promoting the growth of shrubs and facilitating establishment and spread of invasive species that were previously limited by light competition. In this research, we present an analysis of illuminance and temperature in a coastal forest transitioning to a salt marsh. Light sensors above the ground surface were used to measure light attenuation of trees and understory vegetation and to observe the effect of reduced canopies at the forest‐marsh edge. Farther from the marsh, where salinity is lower and trees are healthy, dense canopies attenuate light. We estimate that during the growing season, tree canopies intercept 50% of illuminance on average. Closer to the marsh, canopy thinning, and tree death allow greater light penetration from above, as well as from the adjacent marsh. These illuminance values are further increased by light penetration from the forest‐marsh edge (edge effect). Here, higher illuminance may permit Phragmites australis expansion. At intermediate locations, trees intercept between 32% and 49% of light and the understory shrub Morella cerifera intercepts a further 45% of penetrating light based on comparisons of illuminance above and below shrub canopies. Light penetration from the edge can also be felt. The presence of M. cerifera reduces the air temperature close to the soil surface, creating a cooler summer microclimate. The tree health state is reflected in the canopy size. The canopy patterns and the edge effect are responsible for light availability distribution along forest‐marsh gradients, consequently affecting the understory vegetation biomass. We conclude that during forest retreat driven by sea level rise, tree dieback increases light availability favoring the temporary encroachment of Ph. australis and M. cerifera in the understory. [ABSTRACT FROM AUTHOR]

The southern Gabès aquifer in southeastern Tunisia faces significant stress due to unsustainable groundwater extraction. This study employs a SEAWAT model to evaluate groundwater losses, salinization mechanisms, and the interaction between the confined aquifer and the Mediterranean Sea. The model, incorporating well pumping rates, regional freshwater inflows from the Matmata Mountain Range, and the Mediterranean Sea boundary, demonstrated high accuracy in simulating hydraulic heads. Findings reveal that regional inflow is only half of the current pumping rate, indicating unsustainable groundwater use. The study also assessed salinity dynamics by modeling the Mediterranean Sea as a constant head and salinity boundary. Results suggest limited exchange between the aquifer and the sea, challenging previous assumptions. While the immediate risks of salinization are low, continued over-extraction could compromise the aquifer's long-term sustainability. This research highlights the need for stricter local groundwater management, offers insights into regional coastal aquifer interactions, and contributes to global discussions on managing stressed aquifer systems. [ABSTRACT FROM AUTHOR]

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

Salinization is an ever-increasing problem that severely affects crop performance and finally agricultural production worldwide. This adverse effect of salinity on crop plants occurs in two phase i.e. ionic and osmotic phase. Plants accumulate osmolytes to combat with the osmotic phase of salinity. Osmolytes are polar, non-toxic, uncharged organic compatible solutes that are easily soluble in nature and do not cause any disturbance in normal cellular functions. Osmotic adjustment is crucial to maintain cell turgidity and membrane stability. Osmolytes also regulates the protein folding essential for mediating stress signalling mechanisms or pathways responsible for tolerance. Additionally, they help maintain thylakoid membrane stability, keeping the plants in photosynthetically active phase under stressed conditions. Osmolytes are broadly classified into three groups: ammonium containing compounds (polyamines and betaines), sugars, amino acids and sugar alcohols. In consideration of immense potential of plant osmolytes under salinity, the present review emphasized on the biosynthesis of various reported osmotically active substances and their involvement in different mechanisms or pathways responsible for salinity tolerance in crop plants. [ABSTRACT FROM AUTHOR]

Soil salinization seriously affects soilmicrobial diversity, and crop yield and quality worldwide. Microorganisms play a vital role in the process of crop yield and quality. Traditional Chinese medicine Glycyrrhiza uralensis Fisch. (licorice) can grow tenaciously in the heavily salinized land. However, the relationship between licorice plants and soilmicroorganisms is not clear. A field experiment was carried out to explore the effects of three different degrees of salinized soils on (i) licorice crop performance indicators, (ii) soil physical and chemical properties, and (iii) the changes in soil bacterial community structure and functional diversity in a semi-arid area of northwest China. The results showed that with the aggravation of soil salinization, the licorice yield, soil nutrients, and the bacterial abundance of Gemmatimonadetes and Myxococcota showed a downward trend, while the concentration of glycyrrhizic acid and liquiritin, and the bacterial abundance of Actinobacteria and Firmicutes showed an upward trend. The change of licorice yield mainly depended on the soil physical and chemical properties (e.g., EC and alkaline hydrolysable nitrogen). The change of licorice quality was more closely related to the change of bacterial diversity. The effect of bacterial diversity on liquiritin was greater than that on glycyrrhizic acid. Among them, Gemmatimonadetes were significantly negatively correlated with liquiritin and glycyrrhizic acid. These findings suggest that the increased soil Actinobacteria and Firmicutes or reduced Gemmatimonadetes and Myxococcota may provide a healthy and suitable living condition for the sustainable development of medicinal plant crops in a salinized soil ecosystem. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) are universally distributed in soils, including saline soils, and can form mycorrhizal symbiosis with the vast majority of higher plants. This symbiosis can reduce soil salinity and influence plant growth and development by improving nutrient uptake, increasing plant antioxidant enzyme activity, and regulating hormone levels. In this study, rhizosphere soil from eight plants in the Songnen saline-alkaline grassland was used to isolate, characterize, and screen the indigenous advantageous AMF. The promoting effect of AMF on alfalfa (Medicago sativa L.) under salt treatment was also investigated. The findings showed that 40 species of AMF in six genera were identified by highthroughput sequencing. Glomus mosseae (G.m) and Glomus etunicatum (G.e) are the dominant species in saline ecosystems of northern China. Alfalfa inoculated with Glomus mosseae and Glomus etunicatum under different salt concentrations could be infested and form a symbiotic system. The mycorrhizal colonization rate and mycorrhizal dependence of G.m inoculation were significantly higher than those of G.e inoculation. With increasing salt concentration, inoculation increased alfalfa plant height, fresh weight, chlorophyll content, proline (Pro), soluble sugar (SS), soluble protein (SP), peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) activity while decreasing the malondialdehyde (MDA) content and superoxide anion production rate. The results highlight that inoculation with G.m and G.e effectively alleviated salinity stress, with G.m inoculation having a significant influence on salt resistance in alfalfa. AMF might play a key role in alfalfa growth and survival under harsh salt conditions. [ABSTRACT FROM AUTHOR]

Introduction: Salinity negatively affects maize productivity. However, calcium lignosulfonate (CLS) could improve soil properties and maize productivity. Methods: In this study, we evaluated the effects of CLS application on soil chemical properties, plant physiology and grain quality of maize under salinity stress. Thus, this experiment was conducted using three CLS application rates, CLS0, CLS5, and CLS10, corresponding to 0%, 5%, and 10% of soil mass, for three irrigation water salinity (WS) levels WS0.5, WS2.5, and WS5.5 corresponding to 0.5 and 2.5 and 5.5 dS/m, respectively. Results and discussion: Results show that the WS0.5 × CLS10 combination increased potassium (K 0.167 g/kg), and calcium (Ca, 0.39 g/kg) values while reducing the sodium (Na, 0.23 g/kg) content in soil. However, the treatment WS5.5 × CLS0 decreased K (0.120 g/kg), and Ca (0.15 g/kg) values while increasing Na (0.75 g/kg) content in soil. The root activity was larger in WS0.5 × CLS10 than in WS5.5 × CLS0, as the former combination enlarged K and Ca contents in the root while the latter decreased their values. The leaf glutamine synthetase (953.9 µmol/(g.h)) and nitrate reductase (40.39 µg/(g.h)) were higher in WS0.5 × CLS10 than in WS5.5 × CLS0 at 573.4 µmol/(g.h) and 20.76 µg/(g.h), leading to the improvement in cell progression cycle, as revealed by lower malonaldehyde level (6.57 µmol/g). The K and Ca contents in the leaf (881, 278 mg/plant), stem (1314, 731 mg/plant), and grains (1330, 1117 mg/plant) were greater in WS0.5 × CLS10 than in WS5.5 × CLS0 at (146, 21 mg/plant), (201, 159 mg/plant) and (206, 157 mg/plant), respectively. Therefore, the maize was more resistance to salt stress under the CLS10 level, as a 7.34% decline in yield was noticed when salinity surpassed the threshold value (5.96 dS/m). The protein (13.6 %) and starch (89.2 %) contents were greater in WS0.5 × CLS10 than in WS5.5 × CLS0 (6.1 %) and (67.0 %), respectively. This study reveals that CLS addition can alleviate the adverse impacts of salinity on soil quality and maize productivity. Thus, CLS application could be used as an effective soil amendment when irrigating with saline water for sustainable maize production. [ABSTRACT FROM AUTHOR]

Previous studies were mostly conducted based on sparse time series and different phenological images, which often ignored the dramatic changes in salinization evolution throughout the year. Based on Landsat and moderate-resolution-imaging spectroradiometer (MODIS) images from 2000 to 2020, this study applied the Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model (ESTARFM) algorithm to obtain similar phenological images for the month of April for the past 20 years. Based on the random forest algorithm, the surface parameters of the salinization were optimized, and the feature space index models were constructed. Combined with the measured ground data, the optimal monitoring index model of salinization was determined, and then the spatiotemporal evolution patterns of salinization and its driving mechanisms in the Yellow River Delta were revealed. The main conclusions were as follows: (1) The derived long-time-series and similar phenological-fusion images enable us to reveal the patterns of change in the dramatic salinization in the year that we examined using the ESTARFM algorithm. (2) The NDSI-TGDVI feature space salinization monitoring index model based on point-to-point mode had the highest accuracy of 0.92. (3) From 2000 to 2020, the soil salinization in the Yellow River Delta showed an aggravating trend. The average value of salinization during the past 20 years was 0.65, which is categorized as severe salinization. The degree of salinization gradually decreased from the northeastern coastal area to the southwestern inland area. (4) The dominant factors affecting soil salinization in different historical periods varied. The research results could provide support for decision-making regarding the precise prevention and control of salinization in the Yellow River Delta. [ABSTRACT FROM AUTHOR]

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

Salinization threatens freshwater resources and freshwater‐dependent wetlands in coastal areas worldwide. Many research efforts focus on gradual or chronic salinization, but the phenomenon is also episodic in nature, particularly in small streams and artificial waterways. In surface waters, salinization events may coincide with storms, droughts, wind tides, and other episodic events. A lack of standardized quantitative methods and metrics for describing and discussing episodic salinization hinders cross‐disciplinary efforts by scientists and others to analyze, discuss, and make recommendations concerning these events. Here, we present a set of metrics that use statistics which describe flow characteristics in rivers and streams as a template for empirically describing and characterizing salinization events. We developed a set of metrics to quantify the duration, magnitude, and other characteristics of episodic salinization, and we apply the metrics to extensive time‐series data from a field site in coastal North Carolina. We then demonstrate the utility of these metrics by coupling them with ancillary data to perform an unsupervised classification that groups individual salinization events by their primary meteorological driver. We provide simple and flexible code needed to compute metrics in any environment experiencing salinization events in hopes that it will facilitate more standardized approaches to the quantification and study of widespread freshwater salinization. [ABSTRACT FROM AUTHOR]

Irrigated agricultural lands in arid and semi-arid regions are prone to soil degradation. Remote sensing technology has proven useful for mapping and monitoring the extent of this issue. To accurately discern soil salinity, it is essential to choose appropriate spectral wavelengths. This study evaluated the potential of the land degradation index (LDI) using the visible and near infrared (VNIR) and the short wavelength infrared (SWIR) spectral bands compared to that of soil salinity indices by integrating only the VNIR wavelengths. Landsat-OLI and Sentinel-MSI data, acquired 2 weeks apart, were rigorously preprocessed and used. This research was conducted over irrigated agricultural land in Morocco, which is well known for its semi-arid climate and moderately saline soil. Furthermore, a field soil survey was conducted and 42 samples with variable electrical conductivity (EC) were collected for index calibration and validation of the results. The results showed that the visual analysis of the derived maps based on the examined indices exhibited a clear spatial pattern of gradual soil salinity changes extending from the elevated upstream plateau to the downstream of the plain, which limits agricultural activities in the southwestern sector of the study area. The results of this study show that LDI is effective in identifying soil salinity, as indicated by a coefficient of determination (R2) of 0.75 when using Sentinel-MSI and 0.72 with Landsat-OLI. The R2 value of 0.89 and root mean square error (RMSE) of 0.87 dS/m for soil salinity maps generated from LDI with Sentinel-MSI demonstrate high accuracy. In contrast, the R2 value of 0.83 and RMSE of 1.24 dS/m for maps produced from Landsat-OLI indicate lower accuracy. These findings indicate that high-resolution Sentinel-MSI data significantly improved the prediction of salinity-affected soils. Furthermore, this study highlights the benefits of using VNIR and SWIR bands for precise soil salinity mapping. [ABSTRACT FROM AUTHOR]

Climate change, driven by anthropogenic activities, profoundly impacts ecosystems worldwide, particularly aquatic environments. This review explores the multifaceted effects of climate change on the phytoremediation capabilities of aquatic plants, focusing on the physiological responses to key environmental factors such as temperature, carbone dioxide (CO2) and ozone (O3) levels, pH, salinity, and light intensity. As global temperatures rise, moderate increases can enhance photosynthesis and biomass production, boosting the plants' ability to absorb and detoxify contaminants, such as metals, pharmaceuticals, and nutrients. However, extreme temperatures and salinity levels impose stress, disrupting metabolic processes and reducing phytoremediation efficiency. Elevated CO2 levels generally stimulate growth and nutrient uptake, enhancing phytoremediation, but can also lead to nutrient imbalances and water acidification, complicating these benefits. Conversely, increased O3 levels cause oxidative stress, damaging plant tissues and undermining phytoremediation efforts. This review also highlights the critical role of light intensity and pH in regulating plant growth and contaminant uptake. Optimal light conditions and moderate pH changes can significantly enhance phytoremediation, while reduced light due to increased water turbidity and extreme pH fluctuations pose significant challenges. The interplay between these factors and the microbial communities associated with aquatic plants is explored, revealing complex interactions that influence overall remediation efficiency. By synthesizing current research, this review provides a comprehensive understanding of how climate change influences the physiological processes of aquatic plants and their phytoremediation capacity. The findings underscore the need for adaptive management strategies to harness the benefits of phytoremediation in mitigating water pollution under changing climatic conditions. This review calls for further research into the synergistic and antagonistic interactions between climate variables to develop resilient phytoremediation systems that effectively address environmental contaminants in a warming world. [ABSTRACT FROM AUTHOR]

Freshwater lenses and their freshwater–saltwater transition zones are affected by climate change. Both sea-level rise and groundwater recharge influence freshwater volume and transition zone thickness. This study used a semi-generic approach to investigate climate change effects on freshwater lenses: a hypothetical island cross-section was combined with real-world boundary conditions. Sea-level projections including tides and storm surges, annual mean sea-level rise data, and monthly recharge projections of several climate models of the German barrier island Norderney in the North Sea were used to evaluate changes in freshwater lens and transition zone size between 1971–2000 and 2071–2100. Firstly, impacts of sea-level and recharge boundary conditions were investigated on islands of different widths. Secondly, a multi-parameter study was conducted focussing on variations of several relevant hydrogeological parameters. Results showed that it is very likely but not certain that freshwater lens volume and depth will decrease and transition zone thickness increase as a consequence of climate change. Model predictions revealed a strong dependency on the employed climate models and to a lesser extent on the hydrogeological parameters, at least for the parameter ranges used in this study. Of all hydrogeological parameters tested, the largest effects were caused by the hydraulic conductivity and its anisotropy. Furthermore, the study showed that boundary conditions have larger impacts on smaller islands. These results illustrate the importance of using projections from climate models in a sufficiently high resolution. Furthermore, their uncertainties and changes in variability of boundary conditions should be considered in studies about climate change impacts on freshwater lenses. [ABSTRACT FROM AUTHOR]

Anthropogenic factors such as over-pumping and natural events such as earthquakes impact coastal aquifers by reducing freshwater recharge, aquifer water budgets, and increasing saltwater intrusion (SWI). This study investigates the impact of hydrodynamic forces induced by earthquakes on SWI in one hypothetical case, namely, the Henry problem, and a real case of the Biscayne aquifer located in Florida, USA. The analysis was carried out using the analytical solution of estimating the earthquake's induced hydrodynamic pressure and applying the SEAWAT code to investigate the SWI for the base case and three scenarios, namely for the horizontal acceleration (αh) by 0.10 g, 0.20 g, and 0.30 g. The results show that earthquakes might considerably increase the SWI in coastal aquifers. Moreover, the rise in salinity across expansive land areas significantly threatens agricultural productivity and jeopardizes food security. Namely, in the case of Biscayne aquifer, salinity was increased by 12.10%, 21.90%, and 45.70% for the horizontal seismic acceleration of 0.1 g, 0.20 g, and 0.30 g, respectively. Hence, the conclusions drawn from this study underscore the need for carefull consideration of earthquake impacts in future planning and water management strategies for coastal regions. This proactive approach is crucial to preemptively address and mitigate the groundwater salinization hazard associated with SWI fluctuations due to earthquakes. [ABSTRACT FROM AUTHOR]

Cultivating edible salt-tolerant plants (halophytes) for human consumption is increasingly important due to climate change and soil salinization, and offers sustainable agricultural solutions. Optimizing seed germination, the crucial initial stage of crop growth, is essential for enhancing crop production. This study aimed to optimize the germination of edible halophytes under greenhouse conditions, focusing on select soil (salinity and substrate) and non-soil-related factors (chemical and mechanical treatments). The target species were selected for their commercial value and included Mesembryanthemum crystallinum L. (crystalline iceplant), Salicornia ramosissima J. Woods (sea asparagus), Medicago marina L. (sea medick), Ammophila arenaria (L.) Link (European beachgrass), Portulaca oleracea L. (common purslane), and Atriplex halimus L. (Mediterranean saltbush). Salinity negatively impacted germination rates (GRs) and delayed mean germination time (MGT) across species. P. oleracea had the highest GR (95.6%) in coco peat under freshwater irrigation, and the shortest MGT (5.2 days). A. halimus did not germinate under the tested conditions. Scarification with sulfuric acid improved the GR of M. marina by 42.2%, while scarification with ultrasounds improved the GR of A. arenaria by 35.5%. Our results indicate that the choice of substrate and the application of specific treatments like scarification can significantly improve the germination of certain halophyte species under variable saline conditions. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of the impact of contaminants on organisms requires consideration of magnitude, duration, frequency, and life-history stage of exposure. Government guidelines provide a benchmark to evaluate exposure magnitude, but solely assessing magnitude does not consider duration and frequency of exposure. High-frequency sampling of data enables better integration of temporal patterns of potential environmental stressors and can inform research about habitat suitability. We develop and demonstrate an approach to examine temporal dynamics of abiotic conditions using high-frequency sampling data to assess water quality in the habitat of a Canadian federally listed endangered fish species, the Redside Dace (Clinostomus elongatus). Urban stressors, including chloride and non-point source pollutants, are considered contributing factors to the decline of Redside Dace in Canada. We collected and analyzed conductivity/chloride data from nine Redside Dace sites with varying degrees of upstream urbanization in the Greater Toronto Area to understand spatial and temporal variation in chloride exposure. Chloride loading in the region is largely driven by application of winter de-icing salt contributing to year-round elevated chloride concentrations. We highlight chloride patterns during critical early life stages of Redside Dace (spring spawning through summer; ‘non-salting season’), when sensitivity to stressors may be heightened. We assessed our data against the federal Canadian and American guidelines and found that at six out of nine sites, critical early life stages were exposed to chloride concentrations that exceeded the magnitude threshold of Canadian guidelines. We found instances of chronic duration threshold exceedance at six out of nine sites. Future research can leverage our approach to identify areas of concern where magnitude and duration thresholds are exceeded, and our results can be used to inform the duration of stressor exposure to critical life-history stages during ecologically relevant laboratory-based ecotoxicology studies. We emphasize that our approach can be used for any environmental parameter sampled with high frequency to better understand temporal regimes of ecological stressors.

In the fight against emerging pathogens, an important management strategy is to identify host refuges to prevent extinctions. Fungal pathogens (Batrachochytrium) are decimating amphibians around the world, but researchers have discovered that coastal amphibians living in high-salt water bodies can experience a refuge because the pathogens have lower survival outside the host in these conditions. This has led to the recommendation that managers should create disease refuges for amphibians by adding salt to water bodies. We review this literature and highlight that while some populations of coastal amphibians have evolved increased salt tolerance, most amphibian populations around the world have not. The relatively high concentrations of salt that are needed to kill the pathogens would cause widespread direct and indirect harm on amphibians and would kill most other aquatic taxa. Thus, intentionally salinizing freshwater habitats is a well-intentioned management strategy, but it is not a well-advised strategy.