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Hot spring geochemistry from the Cordillera Blanca and Cordillera Huayhuash, Peru, reveal the influence of crustal‐scale structures on geothermal fluid circulation in an amagmatic region located above a flat‐slab subduction zone. To test the influence of contrasting modes of faulting in these regions, springs were targeted along the Cordillera Blanca detachment fault, within its hanging wall, in the footwall of the detachment, and in the Cordillera Huayhuash. Hot springs along the Cordillera Blanca detachment fault zone are associated with recent extension and normal faulting, and those in its footwall and the Cordillera Huayhuash are located in the Marañon fold and thrust belt where compressional structures dominate. Springs along and in the hanging wall of the Cordillera Blanca detachment fault yield brackish‐saline, alkaline‐chloride waters, with oxygen, hydrogen, carbon, and chlorine stable isotope values that suggest mixing between meteoric groundwater and saline brine affected by high water‐rock interaction. Geothermometry reservoir temperature estimates (RTEs) of 91–226°C indicate maximum flow path depths of 8.7 or 11 km, depending on geothermal gradient, associated with the Cordillera Blanca detachment fault. In contrast, springs in the footwall and in the Cordillera Huayhuash exhibit a wide range of water types with an isotopic affinity to meteoric water, suggesting a greater influence from shallow groundwater and less water‐rock interaction. For these springs, RTEs of 40–98°C correspond to much shallower circulation (1.6–4 km). Results indicate that the Cordillera Blanca detachment system accommodates significantly deeper circulation of crustal fluids compared to other regional compressional structures. Key Points: The Cordillera Blanca detachment hosts a hydrothermal system and deep flow pathsHot spring aqueous and isotope geochemistry reveal crustal fluid sources, temperatures, and mixingContrasting structural styles in the Cordillera Blanca and Cordillera Huayhuash influence water‐rock interaction and groundwater chemistry [ABSTRACT FROM AUTHOR]

Saline intrusion (SI) is increasing at an accelerating rate in the coastal zones of the Vietnamese Mekong Delta (VMD). This challenges various crop production practices in these areas. Using ecological and social approaches, this paper aims to explore farmers' perceptions of SI occurring in Tra Vinh and Kien Giang provinces, and their adaptation measures to deal with the situation. A mixed-method approach was used, including in-depth interviews, focus group discussions, and household surveys. The results demonstrated that farmers have implemented various adaptation measures in tackling SI impacts. High market demand for shrimp also contributed to farmers' decisions in shifting farming practices. The study underscores the important role of the integrated shrimp-rice system as a more comparatively sustainable model to the intensive shrimp culture in the face of SI. Qualitative analysis revealed water conflicts occurring in mixed rice and shrimp farming areas driven by the poor performance of combined irrigation and drainage systems together with the undefined water demarcation zones between rice and shrimp farmers. The paper provides better insights into how farmers' adaptation strategies could facilitate decision-making processes with regard to water management and adaptation policies in the coastal areas. It calls for local governments' attention to modifying water infrastructure to better address water-related issues. [ABSTRACT FROM AUTHOR]

Because of the importance of the Asmari Formation in Lurestan zone (north of the Zagros basin), Jahangirabad section with a total thickness of 179 meters consist of mixed limestone-evaporites have been studied in order to interpretfacies, paleoenvironment, sequence stratigraphy and diagenetic processes. Based on lithostratigraphic classification in Lurestan zone by Adams studies, the Asmari Formation (Late Oligocene – early Miocene deposits) in study area has been divided into 3 units (including 5 sub-units). According to the field studies and laboratory works, 13 microfacies in 5 facies association were recognized, which belong to open marine, shoal, lagoon, intertidal environments. By considering the Lower Kalhur evaporites (with observed micro-texture), which are located in the lower part of this formation, it seems that the precipitation of these evaporates has occurred in the restricted basin during fall of sea level in saline environments. The precipitation of limestone with pelagic fauna has occurred over basal anhydrite during the rise of sea level. The main recognized diagenetic processes are dissolution and dolomitization which has influence on Asmari formation in this region. Three depositional sequences were identified based on facies distribution and sequence boundary. [ABSTRACT FROM AUTHOR]

Interaction of Se up to 8 mg kg−1 soil and Cd at 5 and 15 mg kg−1 soil in wheat at different salinities was evaluated. Se concentrations in wheat shoots were progressively increased in parallel to Se in soil but decreased by addition of Cd. With increasing salinity, Cd concentrations increased and Se decreased. At low salinity, low addition of Se to the soil reduced Cd accumulation. At moderate and high salinities, only high Se amendment led to decline in Cd uptake, at the expense of reduction in biomass yield. Se at 0.5 mg kg−1 soil alleviated the negative effect of Cd on shoot yield. [ABSTRACT FROM AUTHOR]

Because highly saline groundwaters are found at potential repository sites for nuclear waste, geochemical models should predict the speciation of relevant radionuclides in brines, including their complexation with substances such as humic acids (HA). In this study, available experimental radionuclide-HA complexation data in high 1:1 background electrolyte solutions (0.01 < m NaCl / NO 3 / ClO 4 < 4 molal, m) are reviewed. Discrepancies in the amplitude of ionic strength effects on radionuclide-HA complexation are observed, which might depend on the nature of the interacting radionuclide or on the origin of HA. However, significant differences in the experimental conditions and calculations applied to determine conditional metal ion-HA complexation constants hamper direct comparison between these datasets. To clarify whether metal ion-HA binding in saline solutions can be described, two sophisticated humic-ion binding models (Model VII and NICA-Donnan) are presently used. This is the first time that Model VII and NICA-Donnan are applied to predict metal ion-HA binding at high ionic strength ( I > 1 m). The advantage of these models, compared to more simple ones (e.g., the polyelectrolyte or the charge neutralization models), is that both electrostatic and chemical contributions to the overall metal ion-HA binding are explicitly taken into account. Model VII and NICA-Donnan are shown to produce very similar results. Trends in conditional metal ion-HA binding constants and in the maximum metal ion uptake by HA (e.g., the loading capacity) with I agree with experiments. The present data evaluation suggests that most of the apparent discrepancies between various experimental datasets arise from differences in the experimental conditions. Both Model VII and NICA-Donnan predict that the specific ion interaction theory (SIT) parameters for metal ion-HA systems, which are required for high ionic strength with more simple models, vary with pH and metal loading. Overall, Model VII and NICA-Donnan are able to account for various mechanisms involved in metal ion-HA complexation, including the metal loading effects and cation competition, and might be helpful predictive tools for performance safety assessment up to highly saline conditions. [ABSTRACT FROM AUTHOR]

Liquid level measurement is an important requirement in many industrial applications. Previously, an inductance method was developed for liquid with an infinite surface area; but the technique is not suitable for liquid with a small surface area, in which case, the analytical approach we developed previously is no longer valid. In this paper, we present a novel approach based on the high frequency electromagnetic induction technique for the measurement of liquid level with a small surface area. To understand the electromagnetic interaction between the proposed sensor and the liquid under measurement, a FEM solver in the thick skin regime is developed for the modeling. The developed 3D solver has the capability to simulate liquid with an arbitrary surface area. An FPGA based instrument has been developed for this measurement application and experiments were conducted in our laboratory. Sensitivity analysis and error analysis have been carried out for selecting optimal coil configurations. Experiment results have shown that under optimal conditions, the level accuracy is within 0.5 mm. This confirmed the validity and effectiveness of our proposed approach based on the high frequency electromagnetic sensing principle. [ABSTRACT FROM AUTHOR]

Seeking a potential erosion control method for saline-sodic soil slopes under coastal reclamation is essential. We investigated the effect of rock fragment covers ( RC ) on the rainfall partitioning, infiltration and runoff processes, and the erosion processes for saline-sodic slopes of 15° and 30° subjected to a 50-min simulated rainstorm with an intensity of 92 mm h − 1 . Six rock fragment covers (0%, 10%, 20%, 40%, 60% and 80%) were investigated. Soil was packed in 200 cm × 100 cm × 30 cm flumes, divided into two to create two replicates for each treatment. Two sequential soil erosion events, E1 followed by E2 , were induced under two rainstorms that were 24 h apart. Results showed that, in general, RC had a positive effect on the runoff rate for both slopes. A logarithmic relationship existed between the steady-state infiltration rate and the RC . For the gentler slopes, an RC between 40% and 60% could protect the soil from erosion for E2 and E1 + E2 events, but did not do so for the E1 events alone. For the steeper slopes, the RC had no effect on soil losses for the E2 and E1 + E2 events, but increased the soil losses for the E1 events. As the situation of rock fragment changed from Situation 1: well embedded into the soil surface to Situation 4: submerged in water , the relationship between RC and soil loss became more complex and might change over time from a positive to a negative one. The results suggested that the effect of RC on runoff and soil losses was influenced by the change of rock fragment situations over time during individual rainstorms. The benefits of RC might be augmented by using them in combination with another protective measure. [ABSTRACT FROM AUTHOR]

Chloride (Cl − ) is an essential plant nutrient but under saline conditions it can accumulate to toxic levels in leaves; limiting this accumulation improves the salt tolerance of some crops. The rate-limiting step for this process – the transfer of Cl − from root symplast to xylem apoplast, which can antagonize delivery of the macronutrient nitrate (NO 3 − ) to shoots – is regulated by abscisic acid (ABA) and is multigenic. Until recently the molecular mechanisms underpinning this salt-tolerance trait were poorly defined. We discuss here how recent advances highlight the role of newly identified transport proteins, some that directly transfer Cl − into the xylem, and others that act on endomembranes in ‘gatekeeper’ cell types in the root stele to control root-to-shoot delivery of Cl − . [ABSTRACT FROM AUTHOR]

Water management in agricultural lands largely depends on quantity and quality of available soil and water resources. In arid and semi arid regions, scarcity of fresh water and soil salinity are two main important limiting factors for crop production. Under such limiting conditions, one practical alternative for crop production is the use of unconventional or brackish water. If used, the quantitative response of plants to salinity must be carefully analyzed by means of modeling. On the other hand, plant response to salinity varies under different growth stages. Durum wheat ( Triticum turgidum L.) is an important crop cultivated in some arid and semi-arid areas across the world such as Middle East and North Africa. This study was aimed to quantitatively characterize the Durum wheat response to salinity under different productive growth stages. Consequently, a large experiment in natural saline sandy loam soil (Typic Toriorthent) with five natural saline water treatments including 2, 4, 6, 8 and 10 dS/m each with three replicates was conducted. Furthermore, four predictive linear and nonlinear models of Maas and Hoffman, van Genuchten and Hoffman, Dirksen et al. and Homaee et al. were evaluated to predict relative transpiration and relative yield of durum wheat under heading and ripening growth stages. Three statistics including modified coefficient efficiency (E'), modified index of agreement (d') and coefficient of residual mass (CRM) were used to compare the used models and to assess their performances. Results indicated that among the examined models, the macroscopic model of Homaee et al. can provide more reasonable predictions at heading stage, while the piece-wise linear model of Maas and Hoffman provided slightly better prediction at ripening growth stage. The obtained threshold value and slope of reduction yield were quite different from those previously reported in the literature. These findings reveal that the widely cited tables describing the relationship between relative yield and electrical conductivity of saturated extract, averaged over the root zone as well as the entire growing season, are quite approximate and carry significant uncertainty. More experimental studies are still needed to obtain reliable data under different growth stages. [ABSTRACT FROM AUTHOR]

Natural polluted insulator surfaces are always coated with various kinds of soluble constituents, and those constituents affect flashover performance differentially. Currently, this fact is not considered either in laboratory experiments or field pollution degree measurements, causing the existing insulation selection method to be deficient. In this paper, a systematic study on insulator flashover voltage gradient correction involving different types of soluble pollution constituents is presented. Using a typical type glass insulator as the sample, its flashover tests, polluted by typical soluble chemicals (NaCl, NaNO3, KNO3, NH4NO3, MgSO4, Ca(NO3)2 and CaSO4), were carried out. Then, the flashover gradient correction was made by combining the flashover performance of each soluble constituent, the equivalent salt deposit density (ESDD) contribution of the seven constituents, and the saturation performance of CaSO4. The correction agreed with the flashover test results of insulator polluted by three types of soluble mixture. Research results indicate that the flashover gradient correction method proposed in this paper performs well in reducing the calculating error. It is recommended to carry out component measurements and flashover gradient correction to better select outdoor insulation configuration. [ABSTRACT FROM AUTHOR]

Saline coastal wetlands, such as mangrove and coastal salt marsh, provide many ecosystem services. In Australia, large areas have been lost since European colonization, particularly as a result of drainage, infilling and flood-mitigation works, often starting in the mid-19th century and aimed primarily towards converting land to agricultural, urban or industrial uses. These threats remain ongoing, and will be exacerbated by rapid population growth and climate change in the 21st century. Establishing the effect of wetland loss on the delivery of ecosystem services is confounded by the absence of a nationally consistent approach to mapping wetlands and defining the boundaries of different types of coastal wetland. In addition, climate change and its projected effect on mangrove and salt marsh distribution and ecosystem services is poorly, if at all, acknowledged in existing legislation and policy. Intensifying climate change means that there is little time to be complacent; indeed, there is an urgent need for proper valuation of ecosystem services and explicit recognition of ecosystem services within policy and legislation. Seven actions are identified that could improve protection of coastal wetlands and the ecosystem services they provide, including benchmarking and improving coastal wetland extent and health, reducing complexity and inconsistency in governance arrangements, and facilitating wetland adaptation and ecosystem service delivery using a range of relevant mechanisms. Actions that build upon the momentum to mitigate climate change by sequestering carbon – ‘blue carbon’ – could achieve multiple desirable objectives, including climate-change mitigation and adaptation, floodplain rehabilitation and habitat protection. [ABSTRACT FROM AUTHOR]

Multiple betaine surfactant PSDA (penta sodium N, N′, N′′-dodecyl diethylene triamine pentaacetic acid) is a kind of Zwitterionic Gemini surfactants with three dodecyls, five carboxylic acid groups and three quaternary ammonium. It has higher surface activities such lower cmc, lower γ cmc , lower IFT and better foaming properties than single chain surfactants, so, as foaming agent, it is used in foam flooding to displace oil in harsh reservoirs. Systematic experiments of foam flooding after water flooding had been performed for saline reservoirs. The foaming ability, stability and FCI (foam composite index) were the key factors to ensure high performance of oil recovery. The foam flooding formula was optimized by good performance of foaming ability, stability and FCI . The co-injection of foam was the most effective mode and the alternative injection of gas and solution was the poorest. The gas liquid ratio could also affect the flooding efficiencies greatly. The optimized gas liquid ratio was proposed as 4:1 for co-injection mode at the reservoirs condition. Results of single cores flooding experiments indicated that the resistance coefficient of the foam flooding was very high and the residual resistance coefficient was very low. Results of dual cores flooding experiments indicated that foam flooding with polymer could contribute 11–20% OOIP (original oil in place) recovery and had excellent profile control ability. Results of pilot test showed recovery oil of foam flooding was very considerable. [ABSTRACT FROM AUTHOR]

The coastal ecosystems of the northwestern Arabian Gulf mostly consist of low lying tidal flats backed by hyper saline marsh (sabkha) and desert. As populations increased, much of this coast has been subject to infill and seaward extension for housing, recreation and industrial development. This has led to degradation of the highly productive intertidal and shallow subtidal marine ecosystems upon which fisheries depend. Further degradation can be expected with future sea level rise, as high evaporation rates will induce hyper saline conditions. Rather than building out into the sea using dredging and infill, an alternative approach is to construct cities on land, safely above future high water levels, by excavating saline desert of low productivity to create marine waterways. Sabah Al-Ahmad Sea City in Kuwait was first connected to the sea in 2004 and, with 3 phases completed, now has 84 km of shoreline in the desert. The waterway system was modeled before excavation and relies solely upon tides and wind for seawater circulation. To date seawater quality has been excellent, meeting all criteria demanded by the Environment Public Authority. Within the waterways, a full range of man-made marine habitats have been created. These include intertidal beaches, tidal flats, mangrove and salt marshes on islands, together with subtidal sand and rock benthic habitats. These have been monitored with daily physical and annual biological surveys. Importantly, this data provides new information on the natural colonization rates and development of Gulf soft substrate intertidal and subtidal marine communities. Within 5 years of opening to the sea, all artificially created marine habitats have a species richness and abundance close to, or exceeding, that of similar open sea natural habitats in Kuwait. Over 1000 species of macrobiota now exist within the desert waterways including 100 species of fish and shellfish. Present work describes the development of these marine communities and provides a baseline for recruitment rates of Gulf marine fauna into non-polluted habitats. [ABSTRACT FROM AUTHOR]

n ongoing project monitors saline dust transportation and accumulation in the Western Junggar Basin to determine the rate and chemical composition of dust inputs to soils and their impact on snow/ice melt and vegetation degradation of the surrounding areas. The 1-year record from ten dust trap sites in the Ebinur region of northwest China reveals that yearly deposition rates fluctuate strongly between different sampling sites. The mass accumulation rates (fluxes) of the dust, including water-soluble solutes and trace element, range from 79 to 381 g m year. With increasing distance from the dry lake bed, dust deposition gradually decreases. The salinity of the dust ranges from about 43 to 185 g kg and the mass-soluble salt fluxes range from 4 to 61 g m year. The types of water-soluble salt are different at different sampling sites. In all samples, the major types of water-soluble salts in the dust are sulfates and chlorides. Sulfate and chloride are the major anions while sodium and calcium are the main cations, and nitrate was not found in any dust samples. Potentially toxic trace elements such as Cd, Cr, Pb, Mn, As, Cu, and Ni are present in all samples, with high levels of Cr, Pb, Mn, Cu, and Ni. The dust is a chemical dust in that it consists of dense fine sulfates, chlorides and potentially toxic elements, and causes serious air pollution, resulting in soil salinization and vegetation degradation and accelerating snow/ice melt. [ABSTRACT FROM AUTHOR]

Abstract: Geological storage of CO2 is a viable option for the mitigation of greenhouse gas emissions. Two main reservoir types exist; porous formations such as saline aquifers or depleted oil or gas reservoirs and, of lesser importance in terms of storage capacity, coal or shale reservoirs. These reservoirs have distinct storage mechanisms; in the porous formations the CO2 is stored within the porosity by compression and/or dissolution in the formation fluid, whereas in coal or shale, the CO2 is primarily stored by adsorption. Geological storage scenarios exist where these two reservoir types could be present within a geological sequence and come into contact with migrating CO2. In order to simulate this situation simulators are required which represent the mechanisms operating for both reservoir types. One aspect of the work presented in this paper involves further development of the coal seam gas reservoir simulator, SIMED II, to include CO2 dissolution in formation waters and a more accurate Equation of State, the Span and Wagner model, to describe CO2 density. The modified model is first tested through a code comparison study with TOUGH2 for CO2 storage in a saline aquifer with dissolution in formation water, which finds that the two simulators are in close agreement. The second component of this paper involved investigating the potential impact that coal seams could have on CO2 storage in saline formations. A series of hypothetical cases are constructed to investigate the impact of coal seams as (1) a layer within the target aquifer above the injection point, (2) two layers separated by an aquifer above the injection point, (3) a layer in the target aquifer below the point of injection, and (4) a layer in the overburden. The results show that coal seams can have a significant impact on CO2 storage and migration behaviour by providing extra storage capacity and influencing the CO2 flow path both vertically and horizontally. The potential impact of coal seams in these scenarios is related to a range of factors but key ones are the adsorption capacity and the permeability. The results also demonstrate that coal seam permeability decrease due to CO2 adsorption induced coal swelling, although regarded as a technical obstacle to CO2 injection in the deep unminable coal seams to enhance coalbed methane recovery and for CO2 storage in coal, would further influence the CO2 flow path, helping to reduce the upward CO2 flow due to buoyancy and pressure. This could act to reduce CO2 contact with cap rocks and lower the risk of CO2 leakage. [Copyright &y& Elsevier]

Summary: This study explores the pathways of salt and water movement from the landscape to the stream across major landforms, in dryland areas of south eastern Australia. It was conducted at the Livingstone Creek catchment (∼43km2) a sub catchment of the Kyeamba catchment, NSW, Australia. An extensive stream salinity field monitoring network between major landforms was developed and data capture occurred from 2002 to 2004. Additional measurements of surface water isotopes were also taken to independently assess responses observed from the detailed monitoring network and assist in determining the sources of water. Flow and salt mass balances were calculated across four gauging stations for each event. The stream monitoring found patterns of salt delivery to streams were consistent during four monitored stream events. In the hill slope and colluvial fill, lower sloped, meta-sediment landforms, stream salinity responses showed the classical salinity response to an event: an initial increase of salinity at the beginning of an event (due to first flush) which then diminished as a consequence of dilution. The main difference between these landforms was that the colluvial fill lower sloped meta-sediments had sodic, low permeability soils near the stream edge. This lead to (1) less variation in stream salinities during event conditions and (2) during low base flow increases in stream salinity occurred as concentrated salts from the stream banks dissolved. For the flatter, alluvial landforms, the salinity response showed quite a different and contrasting temporal pattern: salinity continued to increase and vary directly with flow during events. For all the landforms, base flow salinity increases as flow diminished after a event although salinity responses were more lagged in the alluvial landform. This different salinity pattern in the alluvial landform is attributed to (1) for event flow, the increased contributions of more saline subsurface lateral flow of soil water from the alluvial landform compared to very fresh direct surface runoff sourced from hillslope landforms upstream and (2) for base flow, seepage of near stream alluvial groundwater through the stream banks that was less saline then the base flow water sourced upstream from the hillslope landforms. The stream water isotope values confirm the above findings by showing that, in the alluvial landforms soil water contributions are important during events and that direct surface runoff with little interaction of soil water occurs from the hill slope landforms during events. Conceptual models describing salt and water movement through the different landforms and under different antecedent catchment wetness conditions are presented. These conceptual models develop our understanding of water and solute (salt) pathways through the landscape to the stream. To date, this is one of the few experimental studies in Australia connecting landscape and stream salinisation. [Copyright &y& Elsevier]

Saline-alkaline stress is a universal abiotic stress that adversely affects plant growth and productivity. Saline-alkaline conditions results in plant abnormal transcriptome expression finally manifesting as defective phenotypes. Considerable research has revealed the active role of microRNA in various stress conditions. This study was aimed to identify novel miRNAs and the miRNA expression patterns in the leguminous model plant R108 (Medicago truncatula). The miRNA contained in the total RNA extracted from Medicago truncatula seedlings (72 h) that had been treated with solutions mimicking saline and alkaline soils was subjected to miRNA deep sequencing. The Illumina HiSeq sequencing platform was used to analyze nine small RNA libraries of three treatment groups: distilled water, 20 mM NaCl + Na2SO4 and 5 mM Na2CO3 + NaHCO3. Sequencing revealed that 876 miRNAs including 664 known miRNAs and 212 potential novel miRNAs were present in all the libraries. The miR159 family, miR156 family, miR2086-3p, miR396, miR166, miR319, miR167, miR5213-5p, miR1510 and miR2643 were among the most expressed miRNAs in all libraries. The results of miRNAs expression under treatments were validated by reverse-transcription quantitative PCR (RT-qPCR). Target gene prediction through computational analysis and pathway annotation analysis revealed that the primary pathways affected by stress were related to plant development, including metabolic processes, single-organism processes and response to the stimulus. Our results provide valuable information towards elucidating the molecular mechanisms of salt/alkali tolerance in Medicago truncatula and provide insight into the putative role of miRNAs in plant stress resistance. [ABSTRACT FROM AUTHOR]

An abstract of the article "Saline Lacustrine Source Rocks and their Generated Gas Composition," by Liu Chenglin and colleagues is presented.