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The Skaftafellsjökull is an outlet glacier in southern Iceland that has been retreating since 1890. While multiple studies have examined primary succession on the foreland of this glacier, no study has examined the distribution of woody biomass on the outwash plain. We investigated the distribution of one species, Betula pubescens, that grows on the foreland moraines and outwash plain of this glacier. The topography of the outwash plain is heterogeneous, consisting of broad bars of outwash gravel and boulders that are separated by narrow incised channels and broader swales. Vegetation on the outwash plain is primarily a moss–heath community. Birch are sparse on the outwash bar tops, but are more abundant and larger in the channels and swales between the bars. Although the area of the channels on the outwash plain is much less than that of the bar surfaces, the woody biomass of the outwash plain is dominated by the birch within these channels. Consequently, the mean woody biomass of the outwash plain exceeds that of the moraines. We propose that the microhabitat of the outwash plain channels provides a favorable environment for the growth of birch, primarily by providing a fine-grained substrate that promotes successful seeding and growth.

Glacierized alpine catchments are rapidly evolving due to glacier retreat and consequent geomorphological and ecological changes. As more terrain becomes ice-free, reworking of exposed terrain by the river as well as thawing of the top layer may lead to an increase in surface and subsurface water exchanges, leading to potential changes in water storage and release, which in turn may impact ecological, geomorphological and hydrological processes. In this study, we aim to understand the current and future hydrological functioning of a typical outwash plain in a Swiss Alpine catchment. As with many other fluvial aquifers in alpine environments, this outwash plain is located at the valley bottom, where catchment-wide water and sediment fluxes tend to gather from multiple sources, may store water and provide specific habitats for alpine ecosystems. Their dynamics are however rarely studied in post Little Ice Age proglacial zones. Based on geophysical investigations as well as year-round stream and groundwater observations, we developed a simplified physically based 3D MODFLOW model and performed an optimized automatic calibration using PEST HP. We highlight the strong interactions between the upstream river and the aquifer, with stream infiltration being the dominant process of recharge. Groundwater exfiltration occurs in the lower half of the outwash plain, balancing out the amount of river infiltration at a daily timescale. We show that hillslope contributions from rain and snowmelt have little impact on groundwater levels. We also show that the outwash plain acts as a bedrock-dammed aquifer and can maintain groundwater levels close to the surface during dry periods lasting months, even in the absence of glacier meltwater, but may in turn provide only limited baseflow to the stream. Finally, we explore how new outwash plains may form in the future in this catchment due to glacier recession and discuss from a hydrological perspective which cascading impacts the presence of multiple outwash plains may have. For this case study, we estimate the total dynamic storage of future outwash plains to be about 20 mm, and we demonstrate their limited capacity to provide more stream water than that which they infiltrate upstream, except for very low river flows ( to 200 L s−1). Below this limit, they can provide limited baseflow on timescales of weeks, thus maintaining moisture conditions that may be beneficial for proglacial ecosystems. Their role in attenuating floods also appears limited, as less than 0.5 m3 s−1 of river water can be infiltrated. The studied outwash plain appears therefore to play an important role for alpine ecosystems but has a marginal hydrological effect on downstream river discharge.

This article presents the results of studies on aeolian processes in the Oświęcim Basin in southern Poland. There are only a few large dunes in the western part (Woszczyce area) of the vast area of the Basin (about 1800 km2), and several dozen small forms (1–3 m high) in the central part (Świerczyniec area) All these forms are located on the outwash plain from the Odra Glaciation – dunes in the proximal part of sandur and small forms in the distal part. Grain size indices were determined for all samples taken at 17 sites, and quartz grain abrasion was examined using mechanical graniformametric and morphoscopic methods. The study found that the fluvioglacial deposits are not very diverse in grain size but significantly differentiated in terms of the degree of aeolization. In the proximal part of the outwash plain, deposits are characterized by very poor abrasion of quartz grains, two-three times worse than those from the distal part. Aeolian sands, in terms of grain size, do not differ essentially from fluvioglacial deposits, and in the distal part of sandur, there are no differences in the abrasion of the quartz grains. Conversely, in the proximal part, there was a significant increase in the degree of aeolization of the dune deposits compared to the source fluvioglacial deposits.

Abstract Most of the Earth's surface has now been modified by humans. In many countries, natural and semi‐natural ecosystems mostly occur as islands, isolated by land converted for agriculture and a variety of other land‐uses. In this fragmented state, long‐distance dispersal may be the only option for species to adapt their ranges in response to changing climate. The order of arrival of species may leave a lasting imprint on community assembly. Although mostly studied at and above the species level, such priority effects also apply at the intraspecific level. We suggest that this may be particularly important in subarctic and arctic ecosystems. Mountain birch (Betula pubescens ssp. tortuosa) is characterized by great intraspecific variation. We explored spatio‐temporal patterns of the first two mountain birch generations on a homogeneous, early successional glacial outwash plain in SE Iceland that was the recipient of spatially extensive long‐distance dispersal ca. 30 years ago. We evaluated the decadal progress of the young population by remeasuring in 2018, tree density and growth form, plant size, and reproductive effort on 30 transects (150 m2) established in 2008 at four sites on the plain and two adjacent sites ca. 10 km away. All measured variables showed positive increases, but contrary to our predictions of converging dynamics among sites, they had significantly diverged. Thus, two of the sites (only 500 m apart) could not be distinguished in 2008, but by 2018, one of them had much faster growth rates than the other, a higher growth form index reflecting more upright tree stature, greater reproductive effort, and much greater second‐generation seedling recruitment. We discuss two hypotheses that may explain the diverging dynamics, site‐scale environmental heterogeneity, and legacies of intraspecific priority effects.

The Skaftafellsjökull is an outlet glacier in southern Iceland that has been retreating since 1890. While multiple studies have examined primary succession on the foreland of this glacier, no study has examined the distribution of woody biomass on the outwash plain. We investigated the distribution of one species, Betula pubescens, that grows on the foreland moraines and outwash plain of this glacier. The topography of the outwash plain is heterogeneous, consisting of broad bars of outwash gravel and boulders that are separated by narrow incised channels and broader swales. Vegetation on the outwash plain is primarily a moss–heath community. Birch are sparse on the outwash bar tops, but are more abundant and larger in the channels and swales between the bars. Although the area of the channels on the outwash plain is much less than that of the bar surfaces, the woody biomass of the outwash plain is dominated by the birch within these channels. Consequently, the mean woody biomass of the outwash plain exceeds that of the moraines. We propose that the microhabitat of the outwash plain channels provides a favorable environment for the growth of birch, primarily by providing a fine-grained substrate that promotes successful seeding and growth. [ABSTRACT FROM AUTHOR]

High mountain environments have shown substantial geomorphological changes forced by rising temperatures in recent decades. As such, paraglacial transition zones in catchments with rapidly retreating glaciers and abundant sediments are key elements in high alpine river systems and promise to be revealing, yet challenging, areas of investigation for the quantification of current and future sediment transport. In this study, we explore the potential of semi-automatic image analysis to detect the extent of the inundation area and corresponding inundation frequency in a proglacial outwash plain (Jamtal valley, Austria) from terrestrial time-lapse imagery. We cumulated all available records of the inundated area from 2018–2020 and analyzed the spatial and temporal patterns of flood flows. The approach presented here allows semi-automated monitoring of fundamental hydrological/hydraulic processes in an environment of scarce data. Runoff events and their intensity were quantified and attributed to either pronounced ablation, heavy precipitation, or a combination of both. We detected an increasing degree of channel concentration within the observation period. The maximum inundation from one event alone took up 35% of the analyzed area. About 10% of the observed area presented inundation in 60–70% of the analyzed images. In contrast, 60–70% of the observed area was inundated in less than 10% of the analyzed period. Despite some limitations in terms of image classification, prevailing weather conditions and illumination, the derived inundation frequency maps provide novel insights into the evolution of the proglacial channel network.

Glacierized alpine catchments are rapidly evolving due to glacier retreat and consequent geomorphological and ecological changes. As more terrain becomes ice-free, reworking of exposed terrain by the river as well as thawing of the top layer may lead to an increase in surface and subsurface water exchanges, leading to potential changes in water storage and release, which in turn may impact ecological, geomorphological and hydrological processes. In this study, we aim to understand the current and future hydrological functioning of a typical outwash plain in a Swiss Alpine catchment. As with many other fluvial aquifers in alpine environments, this outwash plain is located at the valley bottom, where catchment-wide water and sediment fluxes tend to gather from multiple sources, may store water and provide specific habitats for alpine ecosystems. Their dynamics are however rarely studied in post Little Ice Age proglacial zones. Based on geophysical investigations as well as year-round stream and groundwater observations, we developed a simplified physically based 3D MODFLOW model and performed an optimized automatic calibration using PEST HP. We highlight the strong interactions between the upstream river and the aquifer, with stream infiltration being the dominant process of recharge. Groundwater exfiltration occurs in the lower half of the outwash plain, balancing out the amount of river infiltration at a daily timescale. We show that hillslope contributions from rain and snowmelt have little impact on groundwater levels. We also show that the outwash plain acts as a bedrock-dammed aquifer and can maintain groundwater levels close to the surface during dry periods lasting months, even in the absence of glacier meltwater, but may in turn provide only limited baseflow to the stream. Finally, we explore how new outwash plains may form in the future in this catchment due to glacier recession and discuss from a hydrological perspective which cascading impacts the presence of multiple outwash plains may have. For this case study, we estimate the total dynamic storage of future outwash plains to be about 20 mm, and we demonstrate their limited capacity to provide more stream water than that which they infiltrate upstream, except for very low river flows (<150 to 200 L s -1). Below this limit, they can provide limited baseflow on timescales of weeks, thus maintaining moisture conditions that may be beneficial for proglacial ecosystems. Their role in attenuating floods also appears limited, as less than 0.5 m 3 s -1 of river water can be infiltrated. The studied outwash plain appears therefore to play an important role for alpine ecosystems but has a marginal hydrological effect on downstream river discharge. [ABSTRACT FROM AUTHOR]

Most of the Earth's surface has now been modified by humans. In many countries, natural and semi‐natural ecosystems mostly occur as islands, isolated by land converted for agriculture and a variety of other land‐uses. In this fragmented state, long‐distance dispersal may be the only option for species to adapt their ranges in response to changing climate. The order of arrival of species may leave a lasting imprint on community assembly. Although mostly studied at and above the species level, such priority effects also apply at the intraspecific level. We suggest that this may be particularly important in subarctic and arctic ecosystems. Mountain birch (Betula pubescens ssp. tortuosa) is characterized by great intraspecific variation. We explored spatio‐temporal patterns of the first two mountain birch generations on a homogeneous, early successional glacial outwash plain in SE Iceland that was the recipient of spatially extensive long‐distance dispersal ca. 30 years ago. We evaluated the decadal progress of the young population by remeasuring in 2018, tree density and growth form, plant size, and reproductive effort on 30 transects (150 m2) established in 2008 at four sites on the plain and two adjacent sites ca. 10 km away. All measured variables showed positive increases, but contrary to our predictions of converging dynamics among sites, they had significantly diverged. Thus, two of the sites (only 500 m apart) could not be distinguished in 2008, but by 2018, one of them had much faster growth rates than the other, a higher growth form index reflecting more upright tree stature, greater reproductive effort, and much greater second‐generation seedling recruitment. We discuss two hypotheses that may explain the diverging dynamics, site‐scale environmental heterogeneity, and legacies of intraspecific priority effects. [ABSTRACT FROM AUTHOR]

Glaciated alpine catchments are rapidly evolving due to glacier retreat and consequent geomorphological and ecological changes. As more terrain becomes ice free, the interactions between surface and subsurface waters become gradually more significant, leading to potential changes in water storage and release, which in turn may impact ecological, geomorphological and hydrological processes. In this study, we aim to understand the hydrological functioning of outwash plains as glaciers retreat. These constitute a fluvial aquifer which appears as a focal point for water storage and alpine ecology and their dynamics have only rarely been studied. Based on geophysical investigations as well as year-round stream and groundwater observations, we developed a simplified physically-based 3D MODFLOW model and performed an optimized automatic calibration using PEST HP. By comparing the model results to field observations, we highlight the strong interactions between the upstream river and the aquifer, with stream infiltration being the dominant process of recharge. Groundwater exfiltration occurs in the lower half part of the outwash plain, balancing out the amount of river infiltration at a daily time scale. We show that hillslope contributions from rain and snow-melt have little impact on groundwater levels. We also show that outwash plain aquifers can maintain groundwater levels close to the surface even during long dry periods. From a hydrological perspective, we finally explore how new outwash plains may form in the future due to glacier recession and discuss what cascading impact the presence of multiple outwash plains may have in such catchments. We estimate the total dynamic storage of future outwash plains to be about 20 mm and we demonstrate their limited capacity to produce more stream water than what they infiltrate upstream, except for very low river flows (< 150 to 200 L s−1). Below this limit, they can provide limited baseflow on timescales of weeks, thus maintaining some moisture conditions potentially beneficial for proglacial ecosystems. Their role in attenuating floods also appears limited, as less than 0.5 m3 s−1 of river water can be infiltrated. Outwash plains appear therefore to play an important role for alpine ecosystems but have marginal hydrological effects on downstream river discharge. [ABSTRACT FROM AUTHOR]

Estimation of groundwater recharge is one of the most challenging subjects in hydrogeology. It is a critical factor influencing the pollution migration, assessment of aquifer vulnerability to contamination, small-scale groundwater budget calculation, modeling of nutrient cycling and detailed flow path calculations. In Poland an infiltration rate method is widely used, which depends on a system of rate coefficients referring to the type of soil in the vadose zone and shows which part of the precipitation actually reaches the water table. The paper presents results of numerical simulations of vertical flow in unsaturated zone of an experimental site located on Brda outwash plain. Two simulations for varying vegetative cover (pine forest and grass) were performed. The results were compared with five infiltration rates classifications.

Successional changes of pine forests were studied in outwash areas characterised by topography with ridges and depressions. The spatial series of pine forests of different stand ages and those that have not experienced the impact of human activities were analyzed. Pine forests in outwash areas form two successional series depending on the different ecotopes. The following successional series occurs at the tops of ridges: boreal green moss pine forest à boreal green moss – dwarf shrub forests à boreo-nemoral pine forest with admixture of birch, oak, spruce à nemoral polydominant spruce broad-leaved forest. Another successional series is formed on gentle ridge slopes: boreal polytric pine forest à boreal bilberry-polytric pine forest à boreo-nemoral pine forest with admixture of birch, oak, spruce à nemoral polydominant spruce broad-leaved forest. We show that ecotope has the leading role in the organisation of cenoses at the early stages of succession: green moss pine forests are formed at high and relatively dry relief sites (ridges) and polytric pine forests are formed on relatively wet ridge slopes. The ecotopic mosaic is complicated by the vegetation pattern created by animals (e.g., seed hawkers) at the intermediate stages of succession. Zoochoric species appear in the community: Vaccinium vitis-idaea, Convallaria majalis, Sorbus aucuparia and Quercus robur more often take root at the top of ridges; Vaccinium myrtillus, Frangula alnus and Picea abies grow on the slopes. The mosaic created by trees is imposed on a mosaic caused by ecotopes and animals at the final stages of succession: tree-fall gaps appear in the place of old dead trees with tree undergrowth. As a result, a heterogeneous community with a number of asynchronously developing gaps is formed in place of homogeneous pine forest

Anhand von zwei Dünenprofilen wird die Art, Dauer und Intensität von spätglazialen und holozänen Flugsand- und Bodenbildungen innerhalb des Pommerschen Sandergebietes dargestellt. Hierfür wurde ein interdisziplinärer Ansatz aus Sedimentologie, Pedologie, Palynologie und Geochronologie verwendet. Während des Spätglazials kommen auf den Sanderhochflächen flache Flugsanddecken zur Ablagerung, unterbrochen durch die Bildung des Finowbodens. Durch die Ausbreitung einer geschlossenen Vegetationsdecke im Frühholozän, erfolgt eine Stabilisierung der Reliefoberfläche mit anschließender Bodenbildung. Nach intensiven mittelalterlichen Rodungen werden die Oberflächen erneut destabilisiert. Es kommt zur partiellen Aufarbeitung der Flugsande resultierend in Dünenbildungen und einem kuppigen Relief. Eine der untersuchten Dünen wurde dabei komplett im späten Subatlantikum gebildet. Diese Studie unterstreicht die zeitlich-räumliche Variabilität äolischer Aktivität, wobei Umlagerungen entsprechender Korngrößen während verschiedener Phasen nach der Deglaziation ermöglicht wurden.

One of the more visible consequences of anthropogenic climate change is the ongoing retreat of glaciers worldwide. Rates of primary succession in the resulting glacial forelands are commonly calculated from a single measurement set using a single set of measurements across a landscape of varying age, but repeated measurements over decadal scales may be a more effective means of examining the rates and trends of colonization and community development. Repeated measurements of vegetation groups in a glacial foreland in southern Iceland demonstrate that successional changes are measurable, as shown by the calculation of the dissimilarity index at sites over a 15 year interval. Inter-site dissimilarity validates the essential paradigm of primary succession, where vegetative coverage increases in the glacial foreland as a function of time and supports earlier interpretations saying that species richness decreases on older surfaces, even as the total vegetation cover increases. However, successional processes are subject to major abiotic factors, such as aspect, which is controlled by landscape topography, and the substrate composition. The glacial moraines and outwash plain are underlain by different substrates which produce separate successional trajectories. Succession on the moraines ultimately produces a birch-shrub-heath community, while the outwash deposits promote development of a moss-heath community.

Little is known about the ecological implications of high-magnitude, low frequency jökulhlaup events in proglacial systems. This study highlights how kettle lakes produced by jökulhlaups in proglacial areas create short-lived ecosystems and increase biodiversity. This research also demonstrates that as ice-margins retreat, creating new proglacial lakes and aquatic habitats, these sites may be increasingly important as sites of biogeochemical cycling and carbon fixing. Using diatoms from the base of former kettle hole lakes formed during the November 1996 jökulhlaup on Skeiðarársandur, south-east Iceland, we investigate the record of changing conditions of these lakes over their short (∼15 year) life span. Diatom assemblages were investigated in sediment sections up to 0.36m deep from the base of two kettle holes, and across a profile of surface sediments in one kettle hole. The diatom assemblages across all kettle holes are dominated by small benthic species (e.g. Achnanthes, Navicula, Nitzschia and Fragilaria spp.), with planktonic species (Cyclostephanos, Stephanodiscus spp.) present in only one kettle hole. The diatom assemblages are characterized by species with high nutrient and alkalinity optima. The variation in the diatom assemblages between different sedimentary units in the kettle holes' basal stratigraphy reflect changes in the proportion of available habitat type (e.g. benthic, planktonic and littoral) resulting from changes in water levels, and changes in water chemistry relating to variations in sediment input (e.g. aeolian accumulation, slumping and re-working) and source of water (e.g. precipitation, ground water, snow melt). A conceptual model for typical kettle lake development in proglacial environments is also presented. [ABSTRACT FROM AUTHOR]

Throughout much of eastern North America, quantitative records of historical fire regimes and interactions with humans are absent. Annual resolution fire scar histories provide data on fire frequency, extent, and severity, but also can be used to understand fire-climate-human interactions. This study used tree-ring dated fire scars from red pines (Pinus resinosa) at four sites in the Northern Sands Ecological Landscapes of Wisconsin to quantify the interactions among fire occurrence and seasonality, drought, and humans. New methods for assessing the influence of human ignitions on fire regimes were developed. A temporal and spatial index of wildland fire was significantly correlated (r = 0.48) with drought indices (Palmer Drought Severity Index, PDSI). Fire intervals varied through time with human activities that included early French Jesuit missions, European trade (fur), diseases, war, and land use. Comparisons of historical fire records suggest that annual climate in this region has a broad influence on the occurrence of fire years in the Great Lakes region.

We report on a silt-rich mantle, generally 35-45 cm thick, on a section of the Outer Port Huron outwash plain in northwest Lower Michigan, known locally as the Buckley Flats. Below the mantle (cap) are coarse, sandy outwash sediments. The study examines various hypotheses on the origin of the silt-rich sediment. The silty cap was sampled at 67 sites across the Buckley Flats; data derived from these sites were kriged to create smoothed surfaces of cap thickness and various textural attributes. The silty cap thins progressively from south to north, away from the Manistee River valley. The cap also becomes progressively siltier and finer-textured, and contents of medium and coarser sands diminish, toward the north, away from the presumed source. We suggest that, during the latter phases of the Port Huron advance, while the Manistee River was carrying glacial meltwater, the Buckley Flats would have been a high, dry, stable landscape, relatively near to the river. Silty sediment probably was transported by wind, out of the Manistee flood-plain, just as it was with larger meltwater rivers in the Midwest, and deposited on nearby uplands. Eolian sediment deposited on the Buckley Flats, however, was more likely to have been preserved than was sediment on nearby, less stable landscapes, or on landscapes much farther away. Thus, we conclude that the silty mantle on the Buckley Flats is loess, making our study the first to document and characterize an extensive loess sheet in Lower Michigan. [ABSTRACT FROM AUTHOR]

The Late Weichselian Tinglev outwash plain in southwestern Denmark slopes gently from east to west, but certain areas of the topography show unusual irregularities. Analysis of LiDAR data reveals a mosaic of smaller areas with pronounced changes in slope magnitude and orientation between neighbouring areas. The outwash plain also features notable changes in elevation across kilometre-long lineaments and areas lying lower and higher than the expected level. The depressions in the area have previously been interpreted as the result of melting dead-ice blocks left by the Late Weichselian ice sheet. However, borehole samples from Lake Tinglev on the outwash plain show that lake sedimentation did not start until the early Holocene (9000 years ago), which is more than 9000 years after the ice sheet had retreated. The topographical irregularities are located above the Tønder Graben structure, and we interpret these as the result of Holocene strike-slip movements along the graben faults resulting in areas of both subsidence and uplift. The deformations of the outwash plain are interpreted as the effect of deglaciation tectonics acting within a limited time frame at the beginning of the Holocene. As the event can be related to stress release from the weight of the Scandinavian Ice Sheet, we expect that other fault zones in northern Europe would be equally prone to reactivation. Tectonic events related to deglaciation would most likely be recurrent, and the stress changes appear to have been able to induce short-lived tectonic instability to areas normally considered tectonically stable. We conclude that this type of tectonics has had a significant impact on topography and sedimentation throughout the Quaternary. [ABSTRACT FROM AUTHOR]

The study area near Chelm in Western Pomerania, NW Poland, is located between the end moraine and outwash plain of the glaciomarginal zone of the Pomeranian Phase (Weichselian glaciation). Four assemblages of deposits are exposed in the Chem pits: gravelly diamictons derived from debrisflows, sandy diamictons derived from hyperconcentrated flows, alternating sand and gravel deposited by sheetflows and sandy deposits filling shallow, braided-stream channels. The first facies association predominates in the proximal part of the transition zone and the last one in the distal part. This spectrum of facies associations, some resembling those of the end moraines and others those of the adjacent outwash plain, is considered to be unique, and is attributed to the formation of an array of coalescent ice-contact fans (‘transition’ fans). Architectural element analysis highlights the southwards change from debrisflow processes accompanied by sheetflows to hyperconcentrated flows and further to channelized streamflow. This transition zone in the present case is c . 1-km wide. It is suggested that analogous transitional zones, with similar or different widths, may have been developed in other glaciomarginal belts and remain to be recognized. [ABSTRACT FROM AUTHOR]

The area under study in this paper was subject to landscape transformations, including changes in hydrographical networks. These changes were especially intense in the second half of the 19th century during the Prussian partition, when extensive hydrotechnical works were conducted. Based on a comparison of cartographic materials at a scale of 1:25,000, Prussian topographic maps from 1874, and Polish maps from the second half of the 20th century, it was found that the hydrographic network has changed significantly. A characteristic anthropogenic pattern of water structures was observed that correlates with certain individual morphological units. In the bottoms of the valleys and hollows there is a dense irrigation network, and in the moraine areas, numerous reservoirs of anthropogenic origin were found that are characterized by a rather small size and circular shape. The drainage density in the area under study has increased from 0.7 to 1.95 km⋅km-2, but the lake percentage has only increased from 1.81 to 1.93%. However, the number of reservoirs has increased from 36 to 675. The anthropogenic water reservoirs were found first and foremost in the area of the uplands, where the reservoir frequency has increased from 0.3 km⋅km-2 to 7.7 km⋅km-2. The results of the conducted research can be used to perform an automatic analysis of the transformations of the water network in Tuchola Forest and other areas of the last glacial extent. The results of the study presented in this paper should also be used when taking any decisions and actions that may lead to changes in water network and water management. The discussed "anthropogenic lakeland" located in the area of poor industrial and urban development, the Tuchola Forest, may also be the premise for verifying views on a large number of lakes situated in kettle holes within the Polish Lowland (Niż Polski). [ABSTRACT FROM AUTHOR]

Outwash plains, such as Skeidararsandur, serve as prototypes for braided river facies and analogs for the Mars Pathfinder and Viking 1 landing sites on the margins of the Chryse Basin. Glacier outburst floods jokulhlaups) have generated some of the largest known terrestrial freshwater flows and recent studies suggest that the stratigraphy of outwash plains sandur) is dominated by sedimentary sequences laid down during jokulhlaups, rather than by braided river facies produced by an ablation-related flow regime. The modern point-source drainage configuration on Skeidararsandur evolved from a diffuse, multipoint distributary system during glacier retreat, when meltwater began to be routed parallel to the ice front. The contemporary pattern of water and sediment dispersal across Skeidararsandur differs from the conditions that prevailed when the ice front was coupled to the sandur, and the November 5-6 1996 outburst flood from Skeidararjokull had little impact on the proximal surface of Skeidararsandur beyond the confines of the entrenched channels that traverse it. Thus, the point-source dispersal system on Skeidararsandur may not provide an exact analogue for the pattern of meltwater dispersal responsible for the sediment assemblage laid down during past jokulhlaups, and caution may be required when comparing conditions on Skeidararsandur to those presumed to have been experienced during massive outburst floods elsewhere. [ABSTRACT FROM AUTHOR]

In the Kaluxung River catchment of the southeastern Tibetan Plateau in China, we identified three Ephedra gerardiana communities on different soils and glacial landforms from 4842 to 4899 m above sea level: a moraine community located on constantly collapsing sandy gravel alpine steppe slopes with exposed bedrock on the outer slope of the terminal moraine of the Qiangyong Glacier on Mt. Kaluxung; an outwash plain community located on a gentle alpine steppe slope with exposed bedrock at the terminal end of the outwash plain in the glacial valley of the southeast side of Mt. Noijinkangsang; and a river terrace community located in an alpine meadow on a rock-scattered flat river terrace along a glacier-fed river in the outwash plain in the glacial valley of the southeast side of Mt. Noijinkangsang. Based on the finding of identical DNA sequences of the intergenic spacers of chloroplast trnT–trnF and trnS–trnfM regions for all Ephedra specimens examined in this study, the E. gerardiana in this study were considered to comprise a genetically homogeneous population. Analysis of the relationship between ephedrine alkaloid profiles of these three communities and soil characteristics showed that the river terrace community in wet alpine meadow had significantly lower ephedrine content than did the moraine and outwash plain communities in dry alpine steppe (moraine community, 1.52 ± 0.44; outwash plain community, 1.42 ± 0.68; river terrace community, 0.33 ± 0.65%DW), but pseudoephedrine content showed the reverse pattern (moraine community, 0.86 ± 0.30; outwash plain community, 0.73 ± 0.60; river terrace community, 1.50 ± 0.71%DW). In addition, total alkaloid (ephedrine and pseudoephedrine) content in the river terrace community (1.83 ± 0.24%DW) was significantly lower than that in the moraine community (2.38 ± 0.64%DW) and outwash plain community (2.15 ± 0.55%DW). [ABSTRACT FROM AUTHOR]

Szumińska Danuta. Uwarunkowania powstania i funkcjonowania torfowiska przejściowego w dolinie Wilczej Strugi w zlewni Wdy = Determinant factors regarding the development and functioning of transition peatland in the Wilcza Struga valley of the Wda catchment area. Journal of Education, Health and Sport. 2015;5(5):165-172. ISSN 2391-8306. DOI 10.5281/zenodo.17489 http://ojs.ukw.edu.pl/index.php/johs/article/view/2015%3B5%285%29%3A165-172 https://pbn.nauka.gov.pl/works/559350 http://dx.doi.org/10.5281/zenodo.17489 Formerly Journal of Health Sciences. ISSN 1429-9623 / 2300-665X. Archives 2011 – 2014 http://journal.rsw.edu.pl/index.php/JHS/issue/archive Deklaracja. Specyfika i zawartość merytoryczna czasopisma nie ulega zmianie. Zgodnie z informacją MNiSW z dnia 2 czerwca 2014 r., że w roku 2014 nie będzie przeprowadzana ocena czasopism naukowych; czasopismo o zmienionym tytule otrzymuje tyle samo punktów co na wykazie czasopism naukowych z dnia 31 grudnia 2014 r. The journal has had 5 points in Ministry of Science and Higher Education of Poland parametric evaluation. Part B item 1089. (31.12.2014). © The Author (s) 2015; This article is published with open access at Licensee Open Journal Systems of Kazimierz Wielki University in Bydgoszcz, Poland and Radom University in Radom, Poland Open Access. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited. The authors declare that there is no conflict of interests regarding the publication of this paper. Received: 15.02.2015. Revised 27.04.2015. Accepted: 08.05.2015. Uwarunkowania powstania i funkcjonowania torfowiska przejściowego w dolinie Wilczej Strugi w zlewni Wdy Determinant factors regarding the development and functioning of transition peatland in the Wilcza Struga valley of the Wda catchment area Danuta Szumińska Instytut Geografii, Wydział Kultury Fizycznej, Zdrowia i Turystyki, Uniwersytet Kazimierza Wielkiego w Bydgoszczy, email: dszum@ukw.edu.pl Słowa kluczowe: sandr Wdy, warunki hydrogeologiczne, torfowisko przejściowe. Key words: the Wda outwash plain, hydrogeological conditions, transition peatland. STRESZCZENIE. Badania przeprowadzono w obrębie niewielkiego torfowiska, zlokalizowanego w środkowej części zlewni Wdy, w strefie przejściowej pomiędzy sandrem Wdy a Wysoczyzną Świecką. Obszar ten charakteryzuje się niewielką jeziornością, natomiast znaczną liczbą torfowisk. Analizowane torfowisko położone jest w niewielkiej dolince, odwadnianej w kierunku Wdy przez ciek, któremu nadano na potrzeby artykułu nazwę Wilcza Struga. Wypływa on z mokradła, wykształconego w rynnie, która rozcina powierzchnię morenową Wysoczyzny Świeckiej. Na podstawie analizy budowy geologicznej torfowiska i jego otoczenia stwierdzono, że powstało ono w zagłębieniu zlokalizowanym na linii odpływu fluwioglacjalnego, możliwe że na linii wcześniejszej rynny glacjalnej lub subglacjalnej. Przetrwanie zagłębienia było możliwe dzięki konserwacji martwym lodem. Świadczy o tym obecność pod serią fluwioglacjalną iłów w otoczeniu zagłębienia i brak tych osadów w jego dnie. Bryła była prawdopodobnie przykryta osadami, które zostały później zniszczone w trakcie odpływu fluwioglacjalnego. Złoże torfu o maksymalnej miąższości 4,5 m wypełnia zagłębienie, którego dolna części rozcina osady morenowe, a górna fluwioglacjalne piaski i żwiry. W odległości 100 metrów w kierunku zachodnim przebiega koryto Wilczej Strugi, które znajduje się 0,5 metra niżej niż spąg torfu w zagłębieniu. Torfowisko oddzielone jest od cieku progiem zbudowanym z gliny, który stanowi lokalny dział wód gruntowych. Na podstawie przeprowadzonych obserwacji składu gatunkowego roślinności stwierdzono, że torfowisko reprezentuje aktualnie typ przejściowy. Udział gatunków świadczących o mezotroficznym i oligotroficznym zasilaniu jest większy w centralnej i zachodniej części torfowiska. Gatunki świadczące o zasilaniu wodami eutroficznymi przeważają w części północnej i południowej. Przebieg powierzchniowego działu wodnego zlewni bezpośredniej zagłębienia wyznacza znacznie większą powierzchnię wschodniej części zlewni, przy czym dopływ podziemny z tej strony obejmuje zapewne jeszcze większy obszar. Powoduje to występowanie szerszej strefy eutroficznej poniżej tego zbocza oraz na północnym i południowym krańcu torfowiska – w strefach progów, przez które następuje ucieczka wody w kierunku dna doliny. ABSTRACT. The study was conducted at a minor peatland located in the middle part of the Wda catchment area, in the transitional zone between the Wda outwash plain and Wysoczyzna Świecka (Fig. 1). The area is characterized by a low lake density index and a significant number of peatlands. The peatland under analysis is found in a small valley drained by a watercourse, for the purpose of the article referred to as Wilcza Struga, towards the Wda river. The watercourse has its source in the wetland formed in a postglacial channel which cuts through the moraine surface of Wysoczyzna Świecka. The geological structure analysis of peatland and the adjacent areas indicates that the peatland had been formed in a depression located along the line of fluvioglacial runoff. It may have been formed over the former glacial or subglacial channel. The depression was preserved with dead ice, as can be concluded from the presence of loam under fluvioglacial series found in its surroundings and lack of these deposits in its bottom. The dead ice block was likely covered with deposits that were later on eroded by fluvioglacial runoff. The hollow is filled with peat having a maximum thickness of 4.5 m. Its upper part cuts through the moraine deposits whereas the lower part incises into fluvioglacial sands and gravels (Fig. 1 and 3). The Wilcza Struga watercourse runs at a distance of 100 m to the west. Its channel lies 0.5 m below the lower-most layer of peat in the depression. The peatland is separated from the water course by a clayey sill, which constitutes a local groundwater divide. Observations of vegetation species composition indicated that the peatland is currently transition. The percentage of species which point at a mesotrophic and oligotrophic supply is higher in the central and western part of the peatland. Species which indicate a eutrophic supply are prevalent in the northern and southern parts of the area. Surface water divide of the depression catchment area overlaps with a significant surface area of the eastern part of the catchment (Fig. 2), whereas the underground water supply coming from that direction may well cover even larger area. This results in the occurrence of a wider eutrophic zone below the slope and in the northern and southern part of the peatland – in the areas of sills, through which water escapes towards the valley floor.

High mountain environments have shown substantial geomorphological changes forced by rising temperatures in recent decades. As such, paraglacial transition zones in catchments with rapidly retreating glaciers and abundant sediments are key elements in high alpine river systems and promise to be revealing, yet challenging, areas of investigation for the quantification of current and future sediment transport. In this study, we explore the potential of semi-automatic image analysis to detect the extent of the inundation area and corresponding inundation frequency in a proglacial outwash plain (Jamtal valley, Austria) from terrestrial time-lapse imagery. We cumulated all available records of the inundated area from 2018–2020 and analyzed the spatial and temporal patterns of flood flows. The approach presented here allows semi-automated monitoring of fundamental hydrological/hydraulic processes in an environment of scarce data. Runoff events and their intensity were quantified and attributed to either pronounced ablation, heavy precipitation, or a combination of both. We detected an increasing degree of channel concentration within the observation period. The maximum inundation from one event alone took up 35% of the analyzed area. About 10% of the observed area presented inundation in 60–70% of the analyzed images. In contrast, 60–70% of the observed area was inundated in less than 10% of the analyzed period. Despite some limitations in terms of image classification, prevailing weather conditions and illumination, the derived inundation frequency maps provide novel insights into the evolution of the proglacial channel network. [ABSTRACT FROM AUTHOR]

Plants typically experience great losses from their reproductive potential represented by ovule production to the post-dispersal crop of viable seed. We examined seed density and viability in a founder population of mountain birch (Betula pubescens ssp. tortuosa), aiming to quantify losses at different stages and examine potential selection forces on the reproduction success of the founder generation of an isolated population. At the time of the study (2017–2020), the population had recently reached reproductive maturity, following its colonization around 1990 through long-distance dispersal onto an early successional outwash plain in southeast Iceland. Seed densities were high, but 89% of apparently intact seeds did not contain an embryo, despite being visually indistinguishable from filled seeds. Externally evident losses amounted to about 45% of the total seed crop and were mostly due to predation by the gall midge Semudobia betulae. When all losses were accounted for, 2.7% of the seed crop remained viable and germinated. Pollen limitation may partially explain the high incidence of empty seeds. Excessive flower production is compatible with the predator satiation hypothesis but cannot explain pre-dispersal losses. Another adaptation to predation, masting, appears poorly developed in Iceland. Our results suggest the presence of constraints on the reproduction potential of the new island population, that are more limiting than in neighbouring populations, and we discuss their developmental, ecological, and environmental correlates. [ABSTRACT FROM AUTHOR]

Recent anthropogenic climate change has caused both glacial retreat and increased vegetative growth on Arctic and subarctic tundra landscapes resulting in changing albedo and energy budgets. Glacial forelands are topographically and ecologically heterogeneous landscapes comprising ice-contact and outwash deposits subject to primary succession. The most recent moraines on the foreland of the Skaftafellsjökull in southern Iceland are mostly unvegetated, but vegetation cover increases with the age in a general sense. Vegetated outwash channel terraces occur between the moraines, and a broad vegetated outwash plain occurs distal to the oldest moraine. Variations in albedo were measured at ground level to determine the specific role of vegetation types and varying substrates. Albedo and coverage by major plant groups were measured along transects established on moraines ranging in age from 20 to 130 years and the terrace of one outwash channel and three locations on the outwash plain. Total vegetation cover and coverage by mosses increases on the glacial moraines largely as a function of time but is subject to strong aspect effects. Total vegetation cover and moss cover are highest on outwash deposits, possibly due to a sheltered aspect and greater uniformity of the outwash surface. Measured albedo exhibits a modest positive correlation with total vegetation cover and a modest negative correlation with rock and soil exposure. The strongest positive correlation was found between albedo and moss cover. The differences in brightness between moraines and outwash deposits are evident visually at the landscape scale on satellite photographs and quantifiable by image-processing software. [ABSTRACT FROM AUTHOR]

Throughout much of eastern North America, quantitative records of historical fire regimes and interactions with humans are absent. Annual resolution fire scar histories provide data on fire frequency, extent, and severity, but also can be used to understand fire-climate-human interactions. This study used tree-ring dated fire scars from red pines (Pinus resinosa) at four sites in the Northern Sands Ecological Landscapes of Wisconsin to quantify the interactions among fire occurrence and seasonality, drought, and humans. New methods for assessing the influence of human ignitions on fire regimes were developed. A temporal and spatial index of wildland fire was significantly correlated (r = 0.48) with drought indices (Palmer Drought Severity Index, PDSI). Fire intervals varied through time with human activities that included early French Jesuit missions, European trade (fur), diseases, war, and land use. Comparisons of historical fire records suggest that annual climate in this region has a broad influence on the occurrence of fire years in the Great Lakes region. [ABSTRACT FROM AUTHOR]