Transport Stream Research Articles

Energetically efficient behaviour may be common in biology, but it is not universal: a test of selective tidal stream transport in a poor swimmer

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 584:161-174 (2017) - DOI: https://doi.org/10.3354/meps12352 Energetically efficient behaviour may be common in biology, but it is not universal: a test of selective tidal stream transport in a poor swimmer Sergio Silva1,2,*, Consuelo Macaya-Solis1, Martyn C. Lucas1 1Department of Biosciences, University of Durham, South Road, Durham DH1 3LE, UK 2Departamento de Zooloxía, Xenética e Antropoloxía Física, Facultade de Bioloxía, Campus Vida, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain *Corresponding author: sergio.silva@usc.es ABSTRACT: Selective tidal stream transport (STST) is a common migration strategy for a wide range of aquatic animals, facilitating energetically efficient transport, especially of species considered poor swimmers. We tested whether this mechanism applies during the upstream migration of a poor swimmer, the European river lamprey Lampetra fluviatilis, in a macrotidal estuary. Lamprey (n = 59) were acoustically tagged and tracked in a 40 km section of the River Ouse estuary (NE England) in autumn 2015. Against expectations, lamprey did not use STST and migrated upstream during flood, ebb and slack tide periods. Lamprey also migrated during both day and night in most of the study area, probably due to the high turbidity. The global migration speed (all individuals, over the entire track per individual) was (mean ± SD) 0.15 ± 0.07 m s-1. The migration speed varied significantly between tidal periods (0.38 ± 0.04 m s-1 during flooding tides, 0.12 ± 0.01 m s-1 during ebbing tides and 0.28 ± 0.01 m s-1 during slacks). It was also higher in areas not affected by tides during periods of high freshwater discharge (0.23 ± 0.08 m s-1) than in affected areas (0.17 ± 0.14 m s-1). If the energetic advantages of STST are not employed in macrotidal environments, it is likely that the fitness costs of that behaviour exceed potential energy savings, for example due to increased duration of exposure to predation. In conclusion, STST is evidently not universal in relatively poor swimmers; its use can vary between species and may vary under different conditions. KEY WORDS: Energy efficiency · Selective tidal stream transport · Fish migration · Telemetry · Estuary · Anadromous · River lamprey · Lampetra fluviatilis Full text in pdf format Supplementary material PreviousNextCite this article as: Silva S, Macaya-Solis C, Lucas MC (2017) Energetically efficient behaviour may be common in biology, but it is not universal: a test of selective tidal stream transport in a poor swimmer. Mar Ecol Prog Ser 584:161-174. https://doi.org/10.3354/meps12352 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 584. Online publication date: December 07, 2017 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2017 Inter-Research.

Stream transport of iron and phosphorus by authigenic nanoparticles in the Southern Piedmont of the U.S.

Authigenic nanoparticles containing iron (Fe) and phosphorus (P) have been identified at the anoxic/oxic interface of various aquatic ecosystems, forming upon the oxidation of reduced Fe. Little is known about the prevalence of these authigenic nanoparticles in streams, their impact on biogeochemical fluxes, or the bioavailability of P associated with them. In this paper we used transmission electron microscopy to document the presence of authigenic (amorphous) nanoparticles, rich in Fe and P, in baseflow of streams in the Southern Piedmont region of the U.S. We used a simple centrifugation and ultrafiltration technique to separate authigenic nanoparticles from truly dissolved (<1 kDa) and crystalline mineral/coarse organic fractions in baseflow, employing three different quality control methods to verify a successful separation: X-ray diffraction, electron microscopy, and stoichiometry of Fe and aluminum. This allowed us to quantify the amount of Fe and P in three different fractions of baseflow: truly dissolved, authigenic nanoparticles, and crystalline mineral/coarse organic particles. For the rural and urban stream in our study, on average, authigenic nanoparticles in baseflow transport 66% of Fe, with baseflow concentrations ranging from 80 μg/L to 650 μg/L. Authigenic nanoparticles also transport an average of 38% of reactive P, depending upon seasonality and time elapsed since the last storm event.

Modeling of Ethylene Absorption from an Ethylene–Ethane Mixture by Silver Nitrate Aqueous Solution in a Hollow-Fiber Membrane Contactor

Convection–diffusion mass transfer in a gas–liquid membrane contactor based on porous polysulfone hollow fiber membranes with a mesoporous (dpore ~ 2 nm) structure of the separation layer has been studied. The characteristics of the membrane contactor have been investigated in the recovery of ethylene from its mixture with ethane using an aqueous silver nitrate solution as the absorption liquid. A procedure based on the method of lines is proposed for calculating a mass transfer in hollow fiber contactor with a longitudinal laminar flow in an array of parallel fibers. An ethylene flux, depending on the process conditions, has been found by solving numerically a set of convection–diffusion equations with allowance for both the chemical reaction in the liquid stream and transmembrane transport.

Transport Stream Files Assembling and Analysis of BER Performance into ISDB-Tb Standard

Transport Stream Files Assembling and Analysis of BER Performance into ISDB-Tb Standard

TCT-259 PERSPECTIVE Trial: Procedural, Clinical and Health Status Outcomes Among Patients Undergoing Chronic Total Occlusion Percutaneous Revascularization

In many plant species only a small proportion of buds yield branches. Both the timing and extent of bud activation are tightly regulated to produce specific branching architectures. For example, the primary shoot apex can inhibit the activation of lateral buds. This process is termed apical dominance and is dependent on the plant hormone auxin moving down the main stem in the polar auxin transport stream. We use a computational model and mathematical analysis to show that apical dominance can be explained in terms of an auxin transport switch established by the temporal precedence between competing auxin sources. Our model suggests a mechanistic basis for the indirect action of auxin in bud inhibition and captures the effects of diverse genetic and physiological manipulations. In particular, the model explains the surprising observation that highly branched Arabidopsis phenotypes can exhibit either high or low auxin transport.

Sex that moves mountains: The influence of spawning fish on river profiles over geologic timescales

A key component of resilience is to understand feedbacks among components of biophysical systems, such as physical drivers, ecological responses and the subsequent feedbacks onto physical process. While physically based explanations of biological speciation are common (e.g., mountains separating a species can lead to speciation), less common is the inverse process examined: can a speciation event have significant influence on physical processes and patterns in a landscape? When such processes are considered, such as with ‘ecosystem engineers’, many studies have focused on the short-term physical and biological effects rather than the long-term impacts. Here, we formalized the physical influence of salmon spawning on stream beds into a model of channel profile evolution by altering the critical shear stress required to move stream bed particles. We then asked if spawning and an adaptive radiation event (similar to the one that occurred in Pacific salmon species) could have an effect on channel erosion processes and stream profiles over geological timescales. We found that spawning can profoundly influence the longitudinal profiles of stream beds and thereby the evolution of entire watersheds. The radiation of five Pacific salmon from a common ancestor, additionally, could also cause significant geomorphic change by altering a wider section of the profile for a given distribution of grain sizes. This modeling study suggests that biological evolution can impact landscape evolution by increasing the sediment transport and erosion efficiency of mountain streams. Moreover, the physical effects of a species on its environment might be a complementary explanation for rapid radiation events in species through the creation of new habitat types. This example provides an illustrative case for thinking about the long- and short-term coupling of biotic and abiotic systems.

Structural characteristics of supersonic mixing enhanced by introducing streamwise vortices

The characteristics of structural evolution and mixing process of supersonic flow downstream a lobed mixer are experimentally investigated using nanoparticle-based planar laser scattering technique. The development and evolution of Kelvin-Helmholtz vortices, large-scale streamwise vortices, and transverse structures are clearly exhibited. The interaction of Kelvin-Helmholtz vortices and streamwise structures accelerates the momentum transport of upper and lower streams in the flow transition region. The streamwise vorticity engulfs transverse structures, causing them to deform so that they are bulged at the lobe trough, which can favor molecular mixing. The emergence of small-scale streamwise structures and horseshoe vortex in the interfacial area of the two streams plays an important role in entraining the surrounding fluid from both sides of the interface into mixing region.

Streaming transport of two dimensional electron gas in AlGaN/GaN/AlGaN double heterostructures

Streaming transports of the two-dimensional electron gas (2DEG) in AlGaN/GaN/AlGaN double heterostructures (DHs) are investigated by using the ensemble Monte Carlo simulation method. The dependence of streaming transport on basic parameters of DHs, such as Al composition, GaN channel width, interface roughness, and temperature, is obtained. It is demonstrated that streaming transports of 2DEG in DHs only can be realized by careful choice of those basic parameters and the externally applied electric field parallel to the interface. Weak alloy disorder (ADO) and interface roughness (IFR) scatterings, which can be obtained by using low Al compositions and wide GaN channels, are of benefit to streaming transport in DHs. On the other hand, it is found that dislocation scattering does not play an obvious influence on the transient drift velocity, compared to ADO and IFR scatterings.

Ethylene promotes pollen tube growth by affecting actin filament organization via the cGMP-dependent pathway in Arabidopsis thaliana

Ethylene and cGMP are key regulators of plant developmental processes. In this study, we demonstrate that ethylene or cGMP promote pollen tube growth in a dose-dependent manner. The etr1-1 mutant was found to be insensitive to ethylene with regard to pollen tube growth, while the growth-promoting effect of ethylene in etr2-2, ein4-4, or ein4-7 did not change, suggesting that ethylene signaling was mainly perceived by ETR1. However, the function of cGMP was not inhibited in etr1-1 and pollen tubes became insensitive to ethylene when the endogenous cGMP level was artificially decreased. This shows that cGMP is necessary for the control of pollen tube growth and that it might be a downstream component of ETR1 in the ethylene signaling pathway. Our study also found that ethylene or cGMP increase the actin bundles and elevated the percentage of relative amount of F-actin, while removal of cGMP decreased actin bundles abundance and altered the ratio of F-actin in the tip and base regions of pollen tubes. In conclusion, our data suggests that ethylene functions as the upstream signal of cGMP, and that both signals promote pollen germination and tube growth by regulating F-actin, which is essential for vesicular transport and cytoplasmic streaming.

Bouldery slope landforms on Mt. Biseul, Korea, and implications for paleoclimate and slope evolution

AbstractIdentification of bouldery landforms in mountains and correctly understanding their formative processes play an important role in reconstructing the geomorphic history of a region. We propose that blocks were liberated by frost cracking and wedging of cliff walls during the last glacial period. However, we further suggest and test four hypotheses comprising different scenarios for preconditioning by chemical weathering and subsequent block transport using terrain analysis, characterization of boulders, and10Be exposure dating. Frost shattering from the backing cliff produced the boulders since the beginning of the last glacial period (~80 ka), and gelifluction transported them downslope throughout the last glacial period. Their activity then entered a dormant phase at the beginning of the Holocene. Distribution patterns of exposure ages of tors and block streams are similar to those of previous studies, implying that bouldery landscapes in the southern Korean Peninsula were likely to be formed by similar processes under periglacial conditions. The timing of active periods in transport of block streams corresponds well with the cold periods identified in regional and global climate proxy records. Interestingly, the activity of block streams in the study area reached a maximum during Marine Oxygen Isotope Stage 3 to 2 when the growth rate of nearby speleothems was lowest.

Surface air quality implications of volcanic injection heights

Air quality implications of volcanic eruptions have gained increased attention recently in association with the 2010 Icelandic eruption that resulted in the shut-down of European air space. The emission amount, injection height and prevailing weather conditions determine the extent of the impact through the spatio-temporal distribution of pollutants. It is often argued that in the case of a major eruption in Iceland, like Laki in 1783–1784, that pollutants injected high into the atmosphere lead to substantially increased concentrations of sulfur compounds over continental Europe via long-range transport in the jet stream and eventual large-scale subsidence in a high-pressure system. Using state-of-the-art simulations, we show that the air quality impact of Icelandic volcanoes is highly sensitive to the injection height. In particular, it is the infinitesimal injections into the lower half of the troposphere, rather than the substantial injections into the upper troposphere/lower stratosphere that contribute most to increased pollutant concentrations, resulting in atmospheric haze over mainland Europe/Scandinavia. Besides, the persistent high pressure system over continental Europe/Scandinavia traps the pollutants from dispersing, thereby prolonging the haze.

System-wide organization of actin cytoskeleton determines organelle transport in hypocotyl plant cells

The actin cytoskeleton is an essential intracellular filamentous structure that underpins cellular transport and cytoplasmic streaming in plant cells. However, the system-level properties of actin-based cellular trafficking remain tenuous, largely due to the inability to quantify key features of the actin cytoskeleton. Here, we developed an automated image-based, network-driven framework to accurately segment and quantify actin cytoskeletal structures and Golgi transport. We show that the actin cytoskeleton in both growing and elongated hypocotyl cells has structural properties facilitating efficient transport. Our findings suggest that the erratic movement of Golgi is a stable cellular phenomenon that might optimize distribution efficiency of cell material. Moreover, we demonstrate that Golgi transport in hypocotyl cells can be accurately predicted from the actin network topology alone. Thus, our framework provides quantitative evidence for system-wide coordination of cellular transport in plant cells and can be readily applied to investigate cytoskeletal organization and transport in other organisms.

Plastic litter in streams: The behavioral archaeology of a pervasive environmental problem

Plastic deposition in hydrological systems is a pervasive problem at all geographic scales from loci of pollution to global ocean circulation. Much attention has been devoted to plastic deposition in marine contexts, but little is known about inputs of plastics into local hydrological systems, such as streams. Attempts to prevent plastic litter must incorporate the role of people's behaviors, so we employ a behavioral archaeological framework to distinguish between various cultural inputs (e.g., littering) and noncultural forces (e.g., stream transport and wind) that affect litter patterns on the landscape. Four sites with varying cultural uses were surveyed monthly for eight months along a creek in Texas, and analysis of the data included chi-square and Kruskal Wallis tests, and abundance indices comparing material types across sites. We found that sites have drastically different distributions in plastic litter, and these patterns appear to align with the cultural uses (hiking, fishing, roadway) and presence or absence of noncultural forces at each site. This information can be used to inform efforts to reduce littering at these and potentially other locations with similar characteristics. This study illustrates that an archaeological framework provides an efficient and accurate way to generate local data on littering behaviors.

URBAN STREAM RESTORATION AND APPLIED PRACTICES IN NORTHEAST ILLINOIS

INTRODUCTION: In-stream and watershed dynamics in urban and urbanizing areas have significant impacts on local property and infrastructure, as well as the quality of the stream itself including: water quality, habitat, physical characteristics, and biodiversity. As land development occurs, natural vegetation and exposed soils are converted to buildings, pavement and other impervious surfaces. This leads to increased runoff during storm events as well as decreasing the time that it takes that stormwater to reach streams, wetlands, and other stormwater storage and conveyance systems. These hydrologic changes in a watershed often occur at a rapid pace which results in rapid destabilization and degradation of streams and rivers. Rivers and streams are naturally dynamic systems. They naturally erode and reshape themselves based on changes to the watershed or the stream itself. Erosion and deposition are natural processes that have always been important components of stream systems and in and of themselves are not undesirable. When natural stream dynamics are rapidly accelerated, however, an entire series of negative impacts to the stream and the biological systems that are depended on the stream occur. Rapid destabilization of streams often leads to significant bank and bed erosion that negatively impact stream health and frequently leads to negative impact to property, buildings and structures, as well as public infrastructure. Past approaches to stream bank and bed stabilization often involved channelization, armoring, and other gray infrastructure techniques to protect public and private property in the effected reaches of streams and rivers without taking into account the overall stream system dynamics. Early stabilization efforts frequently led to other unintended consequences by accelerating the rate of bank and bed erosion in untreated reaches, inadvertent flooding, and other infrastructure impacts. The complex nature of stream dynamics and fluvial geomorphology when applied to urban stream systems and significantly modified watersheds require the need for detailed analysis of the morphology of the stream. Consideration of the complex factors and processes that make up fluvial morphology are critical when selecting practices or methods of stream restoration. Many agencies and cooperative partners work to accumulate and analyze case studies and detailed research in order to develop a method of evaluating and prescribing different stream restoration techniques based on the morphologic conditions in the stream reach (Lyn D.A., and Newton J.F., 2015). An accumulation of case studies, research, and scholarly work on stream restoration techniques and practices helps shape and inform designers across multiple agencies in order to effectively select and design restoration practices. Ultimately, in urban streams, the designer is working to establish a condition of dynamic equilibrium in the treated stream reach. Dynamic equilibrium is defined as a stream reach that is in balance with sediment transport, aggradation, degradation, and bank and bed erosion. When those characteristics are in balance based on the inputs of sediment within the watershed, the bed load and sediments the stream transports, and discharge rate and volume, then the stream is considered to be in a relatively stable state (FISRWG, 1998). The selection then of stream restoration and stabilization practices in urban areas is dependent on not only the reach being treated, but also on the overall watershed dynamics. In addition to the physics of the actual practices implemented, including resistance to shear stresses and velocity of the water flow within the stream channel being treated, the practices must also take into account the larger picture of stream dynamics including sediment delivery and transport, within the watershed and not just within the treated reach. Successful urban stream restoration and stabilization techniques mimic the structures found in more undisturbed systems through the utilization of similar materials in an engineered configuration. In many streams the use of a combination of hard and soft armorment and stabilization solutions including stone, woody debris materials, modern geosynthetic reinforcement devices and native vegetation to stabilize and naturalize stream channels, thereby provided enhanced habitat, better water quality, and protecting property and infrastructure.

Zonal evolution of Alaskan Stream structure and transport quantified with Argo data

The Alaskan Stream (AS) flows west-southwestward along the south side of Alaska and the Aleutian Island Arc; a western boundary current at the northern edge of the North Pacific subpolar gyre. The Argo float array has improved sampling of the Gulf of Alaska, allowing quantification of the AS's zonal evolution from 140°W to 175°W. Geostrophic alongshore transport of the AS in the upper 1000 dbar referenced to an assumed level of no motion at 1000 dbar shows little change from east to west. However, alongshore absolute geostrophic transports in the top 2000 dbar (obtained by combining mean absolute 1000-dbar velocities from float displacements with the geostrophic velocity fields) generally increase to the west. We estimate full-depth transports by fitting a barotropic and the first two baroclinic modes calculated from a climatology to the absolute geostrophic velocities in the upper 2000 dbar and applying the velocities from these fits from 2000 dbar to the seafloor. Flowing west from its formation region at 140°W–145°W the full-depth AS becomes stronger, more barotropic, and also narrower once it reaches ∼160°W, with along-shore transports increasing from −16.4 ± 4.9 Sv (1 Sv = 106 m3 s−1) at 140°W to −32.6 ± 5.2 Sv at 175°W. Mean concentrations of relatively warm, salty, oxygen-poor, and nutrient-rich Pacific Equatorial Water (PEW) in the AS decrease from 17.8% ± 0.3% to 8.5% ± 0.5% between 140°W and 175°W. However, the volume transport of PEW by the AS exhibits little change over the PEW density range between these longitudes.

Analytical model of stream transported media

For transmission of packetised media, real-time communications rely on the real-time protocol (RTP). RTP traffic, however, is transmitted over datagram-based transport that allows fast delivery of media. Internet firewalls are typically configured to allow web friendly traffic that uses stream-based transport instead and, simultaneously as security measure, reject any other type of transport. A mechanism to overcome this limitation is by switching transport such that media frames that would be rejected by firewalls are transmitted on top of stream transport. In this study, a novel mathematical model that links application layer packet loss to bursty network packet loss in the context of fading channels characteristic of wireless communications is presented for both, datagram and stream transport. This model is compared with experimental scenarios applied to state-of-the-art speech codecs in order to obtain quality scores that can be correlated against theoretical loss probabilities.

Performance Evaluation of the Emerging Media-Transport Technologies for the Next-Generation Digital Broadcasting Systems

Moving pictures experts group (MPEG) media transport (MMT) and MPEG-dynamic adaptive streaming over hypertext transfer protocol (MPEG-DASH) are emerging as the content-delivery technologies for the next-generation broadcasting systems, as they seamlessly utilize various underlying delivery networks to provide hybrid multimedia services in any location. In this paper, we present an empirical analysis of the channel-zapping time, which is an important metric in the measurement of the quality of experience (QoE) of broadcast services, regarding the MMT and MPEG-DASH technologies. During this process, we also clarify the important factors that determine the channel-zapping time of the individual technologies. In addition, we propose a simple yet effective method that enables fast channel zapping for the MMT technology.

A dissipative particle dynamics study of a flexible filament in confined shear flow.

In this paper, we investigate the dynamics of a tethered flexible filament due to fluid flow inside a microchannel. We use the finite sized dissipative particle dynamics (FDPD) approach to model this problem. The flexible filament is modeled as a bead-spring system with both extensional and flexural rigidity. The influence of flow rate and bending stiffness on the filament dynamics is studied in terms of the different conformational modes obtained. The competing effects of the hydrodynamic force and elastic force in the presence of Brownian thermal effects of comparable order influence the mode shapes of the filament. The dynamics of the filament motions are further analyzed using proper orthogonal decomposition. An important consequence of the dynamics of the filament is that it causes cross-flow in the micro-channel, which could potentially be exploited in micro-mixing and pumping applications. The cross stream fluid transport is observed to be more pronounced for higher bending stiffness.

THE MODEL OF MANAGEMENT OF TRANSPORT FLOWS IN MODERN CONDITIONS

This article discusses a new model of traffic management through an integrated analysis of transport and passenger flows, which will reduce the load on the road network (UDS). Thus solves the following main tasks: justification of the indicators and criteria of the system of transport service of the population of the city is the development of algorithm of calculation and download of UDS city. The technique for managing the transport network by optimizing the composition of the transport stream and use a new criterion of load factor of road network of UDS from different types of passenger transport, including individual. Based on the proposed algorithm of calculation of the load on the main network of the city, given the volume of passenger transportation, presents a quantitative assessment of the options for the development of urban passenger transport (ATG) in the cities of the Russian Federation.

Chemical weathering trends in fine-grained ephemeral stream sediments of the McMurdo Dry Valleys, Antarctica

We investigated chemical weathering trends within the fine-grained (<63μm; silt and clay) fraction of sediments collected from meltwater streams emanating from glaciers in the McMurdo Dry Valleys (MDV; Wright and Taylor Valleys) by integrating grain size, BET surface area, and whole-rock geochemistry. While both valleys currently host cold-based glaciers, the sediment underlying the ephemeral glacial streams was deposited under differing glacial conditions. In Wright Valley (Clark Glacier stream), Brownworth and Trilogy drifts were deposited via cold-based glaciation, whereas the Ross Sea drift that underlies Delta Stream in Taylor Valley likely reflects contributions from wet-based ice. Wright Valley stream sediments are typically coarser grained and have a higher silt content as compared to Taylor Valley sediments. These sediments consist primarily of pyroxenes, quartz, and feldspars, with the percentages of pyroxenes and quartz systematically increasing downstream. The percentage of phyllosilicates ranges from 4 to 18% and decreases with downstream distance. In contrast, Taylor Valley sediments (Delta Stream) are finer-grained and exhibit lower percentages of both pyroxene and quartz and a significantly higher percentage of phyllosilicates (30–43%). Concentrations of all mineral phases remain relatively consistent in abundance with downstream transport in the Delta Stream transect as compared to Clark Glacier stream sediments. Standard chemical weathering indices, such as the Chemical Index of Alteration (CIA), indicate that chemical weathering is occurring within the silt and clay fractions of Antarctic stream sediments and is particularly pronounced in Delta Stream sediments that have BET surface area measurements >40m2/g. Utilization of MFW (mafic-felsic-weathered) and A-CN-K (Al2O3-CaO+Na2O-K2O) plots, however, are more effective in discerning the extent and nature of chemical weathering in these stream systems. Ca and Na depletion observed within the sediments exhibiting the highest surface area in Delta Stream suggest that chemical weathering may result in pitting and/or incongruent dissolution of pyroxenes and feldspars, as well as the development of amorphous and/or nanophase weathering products. In contrast, Clark Glacier stream sediments do not have similar leaching trends in the fine-grained sediment fraction and exhibit minimal weathering overall. This may suggest that fine-grained material is being trapped on top of the Clark Glacier surface and has not yet been transported into the weathering environment of the hyporheic zone due to timing of sampling. Alternatively, complete dissolution of very fine-grained sediment could be occurring in this stream transect, and is therefore not preserved in the fine sediment fraction. Overall, the magnitude of chemical weathering observed between the two stream systems is ultimately related to the nature of the underlying drift (cold and wet-based drift deposition), dispersal patterns of eolian fines, and variable stream discharge rates. Thus, incorporation of local fine-grained sediment derived from the underlying glacial drift deposits and distributed via the varying wind regimes within the hyper-arid climate into active stream channels may facilitate incongruent mineral dissolution and development of weathering products, and ultimately influence the composition and concentration of meltwater stream solutes.