Small River Valley Research Articles

Sediment generation and soil mound denudation in areas of high-density tree throw along a river valley in the Jura Mountains, Switzerland

A preliminary field-based investigation was undertaken in a small (< 10 km2) river valley located in the mountainous Jura region of northwest Switzerland. The aims of the work were to assess sediment generation and annual sediment transport rates by tree throw on forested hillslopes, and to document surface hydrology characteristics on four fresh soil mounds associated with recent tree throws over a 24-day monitoring period. For the soil mounds, average sediment recovery ranged from 7.7–28.2 g (dry weight), equivalent to a suspended sediment concentration of 145.2–327.8 g L−1, and runoff coefficients ranged from 1.0%–4.2%. Based on a soil bulk density value of 1,044 kg m−3, upslope runoff generation areas were denuded by an average 0.14 mm by the end of the 24-day monitoring period, representing an erosion rate equivalent to 2.1 mm yr−1. A ca. 50 cm high soil mound could therefore feasibly persist for around 200–250 years. For tree throw work, the dimensions of 215 individual tree throws were measured and their locations mapped in 12 separate locations along the river valley representing a cumulative area equivalent to 5.3 ha (av. density, 43 per ha). Tree throws generated a total of 20.1 m3 of fine-sediment (< 2 mm diameter), or the equivalent of 3.8 × 10−4 m3 m−2. The process of tree throw was originally attributed to two extreme weather events that occurred in west and central Europe in late December 1999. Taking the 18-year period since both storms, this represents an annual sediment transport rate of 2.7 × 10−5 m3 m−1 yr−1. Exploring the relationship with wind on fall direction, 65.5% of tree throws (143) generally fell in a downslope direction irrespective of hillslope aspect on which they were located. This infers that individual storms may not have been responsible for the majority of tree throws, but instead, could be associated with root failure. Given the high density of tree throws and their relative maturity (average age 41 years), we hypothesise that once trees attain a certain age in this river valley, their physiognomy (i.e. height, mass and centre of gravity) compromises their ability to remain securely anchored. We tentatively attribute this possibility to the presence of bedrock close to the surface, and to the shallow soil profile overlaying steep hillslopes.

Elemental composition of biogenic sediments reveals palaeoclimatic changes during the Late Weichselian in a Central European river valley: A statistical approach

Five sections of sediment from mire infillings located in different part of the catchment small river valley in central Europe were studied by lithological and geochemical analysis in order to examine the response of aquatic ecosystems to the environment changes during Late Weischselian (LW). Differentiation of geochemical composition and grain-size properties in biogenic deposits is being considered as a result of change hydroclimatic conditions and geology structure in individual parts of the catchment. The principal component analysis (PCA) and clustered by hierarchical method (HCA) were chosen to create the lithogeochemical facies and their chronostratigraphy variability. Biogenic sediments of the studied river mires, regardless of the location in a given reach of the valley, are represents mainly by mineral or organic-mineral lithogeochemial facies with increased of lithophilic elements (Na, K and Mg). Similar chemical composition of gyttja and peat sediments in almost all periods of LW, indicate the strongly mechanical denudation processes in the Grabia River valley. The major process, conditioning the development of the mires (in it type and rate sedimentation), was the variable terrigenous material input which are related to its variable dynamic of floods. The higher than expected chemical denudation probably a result of specific groundwater flow direction and dissolving vari-grained sands and silts, which build plains in the central part of the study catchment. The number and thickness of individual lithogeochemical facies are caused by differences in the potential volume of the hydrologically active zone and geological conditions of the emerge or disappear permafrost.

Трансформация водосборных бассейнов центра Москвы под влиянием градостроительства

The center of Moscow has a lengthy and complex evolution. One of its characteristics is a dense network of underground communications of different ages (including manifolds of small rivers). Comparison between the “Leveling plan of the Moscow city” (1888) and the topographic map of Moscow (1984) doesn’t show significant changes of the city center’s relief whose absolute level’s rise hasn’t exceed 0.6 m at an average. Studying small underground rivers, such as Neglinnaya, Presnya, Chichera and Zolotoy Rozhok reveals that since the late 19th century till present time, anthropogenic changes have reduced the density of the drainage network nearly to zero and enlarged the subhorizontal surfaces. Geomorphologic processes have ceased in small urban river valleys on the surface, but suffusion-subsidence phenomena, flooding and deformation of buildings and structures intensify around rivers hidden in collectors, which causes significant damage to the urban economy. The structure and morphometry of watersheds has been simplified, and a significant part of their area has become impermeable. Therefore, despite the reduction in the slope of the terrain, flow velocity, power of the streams, and their erosive potential increased. A threat of rainfall floods still remains.

THE GEOTOURIST ATTRACTIVENESS OF ŁAGOWICA RIVER VALLEY (HOLY CROSS MOUNTAINS, POLAND) – A PROJECT OF A GEOTOURIST TRAIL

Geotourist evaluation of thirteen small geological, geomorphological and mining heritage objects was carried out in a small v alley of the Upper Łagowica River and in its surroundings (Holy Cross Mountains, Poland). The point grading method was used, which is functional in the case of evaluation of small geotourist objects. It was shown that the analysed objects are characterized by high and medi um geotourist attractiveness. When analysed together, they strengthen their own individual values. They are suited to mark out geotourist trails ( geotrail), and additionally become a source of information about spatial changes of geodiversity. They also determine the uniqueness of this type of small river valleys of the Holy Cross Mountains on a regional and supra-regional scale. The evaluation of these objects and the proposal of a geotourist trail in the Upper Łagowica River valley may contribute to the activation of local communities and government authorities in the promotion of geoeducation and geotourism, draw their attention to the need for preservation and protection of the geodiversity of small va lleys of the Holy Cross Mountains, and, what is especially important, may give information about the investment attractiveness of the area.

Forest communities of the Salair ridge as habitats of protected lichen species

For a comprehensive assessment of the habitats of rare and vulnerable lichen species, four key sites inthe Eltsovsky, Togulsky and Zarinsky districts of the Altai territory were studied, which described plant communities –spruce forests, forests with spruce and cedar pine, as well as fir-aspen forests. In total, 20 geobotanical descriptionswere performed, each with an area of 400 sq. m; the vertical and horizontal structure and composition of species weredescribed. Fir-aspen forests and their derivatives are distributed along the peaks and slopes and are dominant in the axialpart of the ridge. They are significantly disrupted by logging. Spruce forests occupy low relief elements – river valleys,small in area. Despite the good development of spruce trees in these forests, they do not have any significant economicsignificance, as they are located in hard-to-reach places, often swampy. However, they can also be transformed as a resultof fires. The main threat to their existence is the process of gold mining in the valleys of small rivers, which destroys notonly spruce forests, but also the entire complex of environmental conditions necessary for their existence. Five species oflichens listed in the Red data book of the Altai territory were found in the studied forests.

Approaches to anthropogenic loads on landscapes in heavily developed regions (On the example of the Chuvash Republic)

Economic activity led to significant transformations of natural landscapes of the Chuvash Republic. There is a change in certain components of geosystems and naturalterritorial complexes as a whole. In order to rationalize environmental management, the analysis of the types and degree of anthropogenic load was carried out. The ratio of different lands was taken as parameters of the analysis. It was based on the share of farmlands, settlement zone, forests and natural landscapes. On the example of the model region of the Chuvash Republic 5 main types of areas were analyzed: upland, slope, terrace, floodplain and valley-river (valleys of small rivers). The factor of different stability of terrain types was taken into account. For uplands it is taken as a unit, and decreases in other types of terrain. On the basis of the analysis of the state of geosystems, the groups of districts were identified and measures were developed to reduce the anthropogenic load on landscapes.

Development of the Solonchak Process in Soils of Small River Valleys in the Taiga-Forest Zone in Relation to the Production of Potassium Salts

Secondary saline alluvial soils formed under conditions of the taiga-forest zone within the Verkhnekamsk salt deposit have been studied. The results of this study indicate that continuous soil salinization is caused by mineralized water filtering from the stored waste products of potash production. The influence of surface and ground waters of chloride–sodium and potassium–sodium composition results in the formation of solonchakous soils and secondary solonchaks. The specific features of these soils—acidity neutralization, gypsum formation, the appearance of carbonates, the entering of sodium and potassium into the soil adsorption complex, and an increase in its base saturation—are described, and further technogenic evolution of alluvial soils is predicted. It is suggested that qualifiers Salictechnic, Chlordictechnic, Gypsictechnic, and Sodictechnic should be added to the system of the World Reference Base for Soil Resources for better characterization of the specific technogenic salinization of soils, which have preserved the main morphological features of the natural profile.

Geomorphology of the urban area of Palermo (Italy)

ABSTRACT The results of a geomorphological study carried out in the urban area of Palermo are summarized in a thematic map. Field survey, analysis of aerial photographs and topographic maps, consultation of historical documents and maps, stratigraphic and topographic reconstruction from numerous wells and subsoil data, and bibliographic search were performed, in order to display the geomorphological changes produced by man over time in a densely populated area and to define the Anthropocene of the study area. Palermo town rises along large marine terrace surfaces cut by small river valleys and bordered by wide degraded and abandoned coastal cliffs. Over the last 2700 years, this area was affected by remarkable man-made changes to topographic surface and underground, exposing large areas of the city to hydraulic, sinkhole, and landslide risks, and increasing the levels of seismic susceptibility. In light of these results, the produced map is useful for urban planning studies.

Comparing Trophic Niches of Sympatric Raptors in Agricultural Landscape in Central Poland

According to basic ecological principle, species that share the same niche do not occupy the same environment for a long time, and sympatry of two or more such species provides an interesting field for the analysis of their trophic niche differentiation. To examine the potential differences in the dimensions of the trophic niche we studied the diet of three sympatric avian predators that prey on colonial Microtus rodents. The study area in central Poland is located in an agricultural landscape, composed of crop fields, as well as meadows and pastures located within a small river valley. The pellets of long-eared owl (Asio otus), barn owl (Tyto alba) and kestrel (Falco tinnunculus) were collected from the 750 m2 study site including church building and its surrounding in the spring of 2016 and 2017. The analysis of pellets provided data on a total of 4128 vertebrate prey individuals (1914 from barn owl, 1749 from long-eared owl, and 465 from kestrel). The most important prey group of all three predators were small mammals (90%, 14 species) and the most frequently preyed species was Microtus arvalis (making up 72% of vertebrate prey of long-eared owl, 59% of kestrel and 53% of barn owl). Despite the general similarity in the diet composition, there were differences in the contribution of several prey species (e.g. Soricomorpha, M. arvalis, Mus musculus, Rattus norvegicus, and Apodemus spp.) and the diversity of the diet between the predators. We conclude that the trophic niches of the studied sympatric species differ in several dimensions, including diel activity, prey size and taxon-specific feeding preferences.

&lt;span lang="EN-GB"&gt;Communities of the Bidentetea class of small coastal river valleys of the Western Pomerania (Poland)&lt;/span&gt;

The aim of work was to investigate the diversification, structure, physiognomy and floristic richness of riverside terophytes from Bidentetea tripartitae class in selected coastal river valleys. The investigates area encompassed the lower and middle section of the river valleys of Rega, Parsęta, Wieprza, Słupia, Łupawa in the Western Pomerania (Poland). 68 phytosociological records were made according to the system of Braun-Blanquet. A database was created with the help of the software Turboveg for Windows.The hierarchy classification with the MVSP package was used in order to arrange and group the collected phytosociological data and to single out the types of plant communities. In order to evaluate similarity of samples with respect to species composition the Bray Curtis was calculated and the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) was applied. Three plant communities belonging to one alliance Bidention tripartitae were identified: Bidenti-Polygonetum hydropiperis (Miljan 1933) Lohmeyer in R.Tx. 1950 nom invers., Bidentetum cernui Kobendza 1948, community with Polygonum minus, and one plant community belonging to the alliance Chenopodion glauci: Chenopodietum rubri Timar 1947.Given the natural origin of most of the patches, their structure, and the relatively small share of synanthropic species, including alien species, it should be emphasized that they constitute a spontaneous stage of succession of riparian vegetation. The presence of therophyte communities in the valleys of the coastal rivers, as well as their structure and physiognomy, testify to the preservation of their natural character.

Geological and geomorphological characteristics of the Paleolithic sites of the northern foothills of the Ile Alatau ridge

In recent years, specialists of the laboratory of "geoarcheology" of the faculty of history, archeology and ethnography of the Kazakh National University named after al-Farabi, together with the staff of the geographical faculty within the northern foothills of the Ile Alatau ridge, conducted geoarchaeological research. The study revealed several Paleolithic sites, the study of which is of great importance for solving the problem of the settlement of the territory of south-eastern Kazakhstan by primitive people of the Stone Age. Materials from the sites Kastek, Kyzylauz-2, Temirlik and Sharyn give an idea of the ways and times of settlement of one of the interesting regions of Kazakhstan - Zhetysu. The variety of geomorphological positions and the finding of artifacts in different layers of quaternary sediments, allows the use of geological and geomorphological methods to highlight the age of sites of ancient human.. Paleolithic sites were found on the valleys of small rivers when they left the mountains in the foothill plans, on the removal cones of temporary watercourses. Stone tools found in the Kyzylaus and Maybulak sites were mainly made of porphyrite. Their sources are the effusive errays of the Lower Carboniferous, widely delevoped in the western spurs of the watershed of the Ile Alatau ridge. The products of destruction of effusive rocks, which formed as a result of their weathering, were activety washed away by mountain rivers into the foothill zones, where they were deposited in the mouth of small rivers and on cones removal of temporary streams.

Functional role of rivers in the ecological structure of the region (the case of the Chuvash Republic)

The article discusses the role of valleys of small rivers in the formation of the ecological structure of the territory. We studied the functional features of small rivers as part of the ecological structure of the region and analysed their ecological status and their ecological role. In this article we identified and described the valleys of the rivers serving as green corridors. In conclusion, we propose strategies to optimize their ecological status.

Development of Pleistocene Fluvial Terraces on the Eastern Frontal Sector of the Southern Apennines Chain, Italy

The investigation of Pleistocene fluvial terraces in the small river valley of the Pescogrosso Stream and surrounding areas has shown a complex and positive location for the study of a fluvial catchment development. The Pescogrosso Stream is a left tributary of the Sinni River and is placed on the eastern front of the fold-and-thrust belt of the southern Apennine chain of Italy. Sedimentological and geomorphological analyses of eight fluvial terraced units revealed that their formation and evolution were strictly controlled by regional tectonic uplift of the Ionian arc, by climatic changes, and by sea-level variations. In particular, the Ionian sea-level oscillations, as a factor in controlling the short-term fluvial terrace development, was the main factor responsible for the three older terraces’ evolutions. Conversely, the evolution of the five younger terraces seems to have been controlled by the base-level variations of the Sinni River. Finally, the matching of much information derived from regional and local tectonics, the plot of longitudinal terrace profiles, and the application of a sequence-stratigraphic approach to fluvial depositional sequences allowed the recognition of three evolutionary stages of development in the Pescogrosso fluvial incised-valley system during Pleistocene times.

The environmental and landscape values of the small lowland river valley and their threats on the example of the Kraska river (Masovian Voivodeship)

The environmental and landscape values of the Kraska River Valley as the typical example of small lowland water flow path were analysed. The WULS-SGGW method, allowing to the estimation of whole valley reach as well as its peculiar eco-morphological zones, was used. The unregulated, regulated in the years 1990– –2012 and continuously maintained from the year 2015 reaches are present in the valley. It was stated that the unregulated reaches characterise themselves by higher environmental values and biological diversity, especially in the case of invertebrate fauna. The invertebrates, as the key element of the river community, quickly rebuild their structure after the termination of maintenance works. The vertebrate fauna, even unconnected strictly with the riverbed, shows higher values on the unmaintained valley reaches.

Mowing may bring about vegetation change, but its effect is strongly modified by hydrological factors

We assessed the effect of long-term (11 years) mowing with a hand scythe on the distributions of plant species and species turnover within meadow communities dominated by Carex acutiformis and C. acuta in a small lowland river valley subjected to annual flooding. We hypothesized that mowing would trigger the process of species exchange toward multispecies communities according to the abiotic environmental gradients, as has been reported for traditionally used wet meadows. We found that mowing had a much greater impact on the increase in plant species abundance in wetter, subjected to deeper and longer flooding, zone of the valley than in its drier part. The treatment and hydrology had no substantial effect on the sedges and cryptogams while the graminoids and the forbs were the least stable components of the plant communities. We found that annual management was conducive to the appearance of numerous seedlings of Alnus glutinosa in the part of wetland situated close to the valley edge. Surface flooding was found to be a driving force modifying the impact of mowing on sedge meadows. This “hydrological resetting impulse” created a specific floristic reset of the community, bringing it to the more simplified forms. Mowing every 4–5 years at the beginning of August is advisable to protect sedge meadows distributed in flooded small lowland river valleys.

Water mites (Acari, Hydrachnidia) of riparian springs in a small lowland river valley: what are the key factors for species distribution?

This paper examines the impact of disturbance factors—flooding and intermittency—on the distribution of water mites in the riparian springs situated in the valley of a small lowland river, the Krąpiel. The landscape factors and physicochemical parameters of the water were analysed in order to gain an understanding of the pattern of water mite assemblages in the riparian springs. Three limnological types of springs were examined (helocrenes, limnocrenes and rheocrenes) along the whole course of the river and a total of 35 water mite species were found. Our study shows that flooding influences spring assemblages, causing a decrease in crenobiontic water mites in flooded springs. The impact of intermittency resulted in a high percentage of species typical of temporary water bodies. Surprisingly, the study revealed the positive impact of the anthropogenic transformation of the river valley: preventing the riparian springs from flooding enhances the diversity of crenobiontic species in non-flooded springs. In the conclusion, our study revealed that further conservation strategies for the protection of the riparian springs along large rivers would take into account ongoing climatic changes and possible the positive impact of the anthropogenic transformation of river valleys.

Records on Anthropogenic Environmental Changes in Small River Valleys in the Vicinity of Łowicz (Central Poland): Their Significance for the Reconstruction of Late Holocene Settlement Tendencies

Based on palaeobotanical analyses of organic deposits, as well as geomorphological and geological studies at four sites in various geomorphological locations in relation to tributaries of the Bzura River, the presence of traces of human activity, its intensiveness, and classification to cultural levels were analysed. A pattern of later and later settlement in areas remote from the axis of the Warsaw–Berlin streamway was observed along with the gradual introduction of settlement from river valley bottoms to watershed zones.

Formation and evolution of back‐barrier perched lakes in rocky coasts: An example of a Holocene system in north‐west Spain

AbstractCoastal back‐barrier perched lakes are freshwater bodies that are elevated over sea‐level and are not directly subjected to the inflow of seawater. This study provides a detailed reconstruction of the Doniños back‐barrier perched lake that developed at the end of a small river valley in the rocky coast of the north‐west Iberian Peninsula during the Holocene transgression. Its sequence stratigraphy was reconstructed based on a core transect across the system, the analyses of its lithofacies and microfossil assemblages, and a high‐resolution radiocarbon‐based chronology. The Doniños perched lake was formed ca 4·5 ka bp. The setting of the perched lake was favoured by Late Holocene sea‐level stabilization and the formation of a barrier and back‐barrier basin, which was contemporaneous with the high systems tract period. This basin developed over marine and lagoonal sediments deposited between 10·2 ka bp and 8·0 ka bp, during rapidly rising sea‐level characteristic of the transgressive systems track period. At 1·1 ka bp, the barrier was breached and the perched lake was partially emptied, causing the erosion of the back‐barrier basin sediments and a significant sedimentary hiatus. Both enhanced storminess and human intervention were likely to be responsible for this event. After 1 ka bp, the barrier reclosed and the present‐day lake was reformed, with the water level reaching as high as 5 m above mean sea‐level. The depositional evolution of the Doniños system serves as a model of coastal back‐barrier perched lakes in coastal clastic systems that have developed over gently seaward‐dipping rugged substrates at small distances from the shoreline and under conditions of rising sea‐level and high sediment supply. A review of estuaries, back‐barrier lagoons, pocket beaches and back‐barrier perched lakes in the rocky coast of north‐west Spain shows that the elevation of the bedrock is the main factor controlling the origin and evolution of these systems.

A Late Medieval motte‐and‐bailey settlement in a lowland river valley landscape of Central Poland

AbstractThe Rozprza motte‐and‐bailey residence in Central Poland was inhabited from the third decade of the 14th century up to the 15th century A.D. and functioned as a seat of a noble family. It was situated in the place occupied previously by an Early Medieval open settlement and a later ring‐fort. The motte was constructed on the river terrace remnant adjoining a strongly expanding flood plain in the central part of the mid‐Luciąża River valley. The immediate surroundings of the stronghold were studied by means of archaeological excavations, detailed geological mapping (hand‐auger transects and trenching), and large‐scale aerial photography, as well as geochemical and geophysical (magnetic gradiometry and soil electrical resistance) prospection. All the results have been integrated within a GIS and supported by a set of 14C dates that allow for a detailed geomorphological reconstruction of the stronghold situation, including former river patterns, the local flood plain development, and the history of the Medieval fortress site with its moats. Our research provides insights into the late Holocene evolution of a small river valley and confirms the favorable conditions for the location of the motte on a terrace remnant protected by the system of moats and surrounding paleochannels and swampy areas within the valley floor.

Пойменные крупнотравные леса острова Сахалин (класс Salicetea sachalinensis Ohba 1973)

Пойменные крупнотравные леса острова Сахалин (класс Salicetea sachalinensis Ohba 1973)