Biogeomorphic effects of woody vegetation on bedrock streams

2019 ◽  
Vol 43 (6) ◽  
pp. 777-800 ◽  
Author(s):  
Tasnuba Jerin
Keyword(s):  
The Other ◽  
Woody Vegetation ◽  
Alluvial Channels ◽  
Dynamic Interactions ◽  
Fluvial Systems ◽  
Stream Bank ◽  
Alluvial Streams ◽  
Tree Uprooting ◽  
Fluvial Environments ◽  
Bedrock Channels

The dynamic interactions between fluvial processes and vegetation vary in different environments and are uncertain in bedrock settings. Bedrock streams are much less studied than alluvial in all aspects, and in many respects act in qualitatively different ways. This research seeks to fill this lacuna by studying bedrock streams from a biogeomorphic perspective. It aims to identify the impacts of woody vegetation that may be common to fluvial systems and rocky hillslopes in general, or that may be unique to bedrock channels. A review of the existing literature on biogeomorphology – mostly fluvial and rocky hillslope environments – was carried out, and field examples of biogeomorphic impacts (BGIs) associated with fluvial systems of various bedrock environments were then examined to complement the review. Results indicate that bedrock streams exhibit both shared and highly concentrated BGIs in relation to alluvial streams and rocky hillslopes. Bedrock streams display a bioprotective geomorphic form – root banks (when the root itself forms the stream bank) – which is distinctive, but not exclusive to this setting. On the other hand, shared biogeomorphic impacts with alluvial streams include sediment and wood trapping, and bar and island development and stabilization (i.e. bioconstruction/modification and protection). Shared impacts with rocky hillslopes also include bioprotection, as well as displacement of bedrock due to root and trunk growth, and bedrock mining caused by tree uprooting (i.e. bioweathering and erosion). Two BGI triangles were developed to graphically display these relationships. Finally, this paper concludes that bedrock streams exhibit some BGIs that also occur in either alluvial channels or on rocky hillslopes. Therefore, no BGIs were identified that are absolutely unique to bedrock fluvial environments.

scholarly journals THE GRASS IS ALWAYS GREENER ON THE OTHER SIDE OF THE FENCE: THE FLORA IN URBAN BACKYARDS OF DIFFERENT SOCIAL CLASSES

2017 ◽  
Vol 20 (1) ◽  
pp. 1-20 ◽  
Author(s):  
FABIO ANGEOLETTO ◽  
JUAN PEDRO RUIZ SANZ ◽  
RICARDO MASSULO ALBERTIN ◽  
FREDERICO FONSECA DA SILVA
Keyword(s):  
Biodiversity Conservation ◽  
Plant Species ◽  
Plant Diversity ◽  
The Other ◽  
Social Classes ◽  
Metropolitan Region ◽  
Woody Vegetation ◽  
Endangered Plant ◽  
Diversity Patterns ◽  
Flora Diversity

Abstract Home gardens have considerable biodiversity conservation potential. However, these spaces are unplanned, and there is little information about the flora diversity in the backyards of different social classes. The current study has quantified and compared plant diversity in the backyards of two neighborhoods located in the metropolitan region of Maringá - RMM (Paraná, Brazil), namely, Conjunto Triangulo and Zona 02. The diversity patterns were markedly different when the neighborhoods were compared. Therefore the present study has set some planning guidelines aiming at increasing the presence of woody vegetation, as well as at contributing to biodiversity conservation, including the conservation of endangered plant species, in the backyards of the RMM.

Depositional Environments of Plant Bearing Sediments

1988 ◽  
Vol 3 ◽  
pp. 1-13 ◽  
Author(s):  
Scott L. Wing
Keyword(s):  
Mass Flow ◽  
Depositional Environments ◽  
Fluvial Systems ◽  
Volcanic Origin ◽  
Sedimentary Environments ◽  
Plant Remains ◽  
Mass Flow Deposits ◽  
Fluvial Environments

Plants can become incorporated into the sediments of virtually any environment, from the oozes of abyssal plains to the silts and sands of delta fronts to brecciated mudflows of volcanic origin. However there is a much narrower range of sedimentary environments in which identifiable plant remains are found in abundance. Generally speaking these are the very shallow or subaerial portions of deltas and estuaries, the channels and floodplains of fluvial systems, lakes of all sizes, ash-falls, and mass-flow deposits such as mudflows. For the purposes of this paper peat swamps are considered as unusual subtypes of deltaic and fluvial environments in which clastic input is low relative to organic accumulation.

scholarly journals The Potential Use of Osl Properties of Quartz in Investigating Fluvial Processes on the Catchment of River Mureş, Romania

2021 ◽  
Vol 14 (1-2) ◽  
pp. 58-67
Author(s):  
Tamás Bartyik ◽  
Cristian Floca ◽  
Elemér Pál-Molnár ◽  
Petru Urdea ◽  
Diaa Elsayed Hamed ◽  
...  
Keyword(s):  
Large River ◽  
Luminescence Properties ◽  
Sediment Provenance ◽  
Fluvial Systems ◽  
Fluvial Erosion ◽  
Main River ◽  
Fluvial Environments ◽  
Compound Surface ◽  
Quartz Grains ◽  
Numerical Dating

Abstract To understand the functioning of fluvial systems it is important to investigate dynamics of sediment transport and the source of sediments. In case of reconstructing past processes these studies must be accompanied by the numerical dating of sediment samples. In this respect optically stimulated luminescence is a widely used technique, by which the time of sediment deposition can be directly dated. Recently, in various fluvial environments it has been shown that certain luminescence properties of minerals, and especially that of quartz, can be applied as indicators of fluvial erosion and/or sediment provenance. These properties are residual luminescence (or residual dose) and luminescence sensitivity of quartz grains. However, the values of the parameters above are affected by various factors, the importance of which is under debate. The present study therefore aims to assess these factors along a ~560 km long reach of River Mureş (Maros) a relatively large river with a compound surface lithology on its catchment. The research focused on the sandy fraction of modern sediments, collected from the main river and from three tributaries alike. This way not only longitudinal downstream changes, but the influence of tributaries could also be studied. Based on the data, both investigated parameters show a great variation, which can be attributed to the lithological differences of subcatchments and geomorphological drivers, such as erosional activity and potential number of sedimentary cycles, and human activity. However, relationships are not entirely clear and are influenced by the maximum grain size of the samples investigated, and the recycling of previously laid deposits with different properties. Still, when performing detailed dating studies, and tracing sediments from certain parts of the catchment luminescence properties can be a useful tool in the future.

Effects of lithology on bedrock channel occurrence: an examination from the Seogang River in South Korea

2021 ◽  
Author(s):  
Hui Chen ◽  
Jongmin Byun
Keyword(s):  
South Korea ◽  
Rock Type ◽  
The Other ◽  
Joint Density ◽  
Transport Capacity ◽  
Stream Power ◽  
Granitic Gneiss ◽  
Bedrock Channel ◽  
Basin Scale ◽  
Bedrock Channels

<div> <p>Bedrock river is rock-bound, its bed and banks are composed mainly of in-place bedrock. Bedrock channel reaches, commonly short and intermittent, often occur where transport capacity exceeds bedload sediment flux. Despite the abundant research on the typical patterns of alluvial channel reaches, the distribution of bedrock channels has not been well studied. Rock type may affect the occurrence of bedrock channels because the strength, joint density, and erosion process of bedrock vary depending on the rock type. Previous studies have viewed the bedrock channel occurrence in the aspect of the excessive sediment transport capacity, but the influence of lithology has not been considered in the literature. To understand the influence of lithology on bedrock channel occurrence in a drainage basin-scale, we investigated the distribution of bedrock channels in relation to varying lithology and unit stream power along the Seogang River in South Korea. We used satellite images with high resolution for the identification of bedrock channel reaches and then verified them through field surveys. Geological maps and 1 arc-second SRTM DEMs were used to analyze lithological effects and calculate unit stream power.  As a result of the analysis, we identified 94 bedrock channels in the studied river, varying depending on lithologies. The frequency of bedrock channels in granitic gneiss areas (0.73/km) is much higher than those in the other rock type areas (granite areas, 0.57/km; limestone areas, 0.16/km). In the more frequent granitic gneiss areas, the bedrock channels are steepened (average channel slope: 0.0074 m/m) and narrow (average channel width: 65 m) and mainly reside within steepened and narrow (average valley width: 123 m) rock-bound valleys so that their occurrence is mainly associated with high unit stream power. In contrast, the bedrock channels over the other lithologies are wider (89 m) and lower-gradient (0.0056 m/m) and occur along flat and broad valleys (391 m). Consequently, the bedrock channels in the studied river were divided into two types: confined and unconfined bedrock channels. The confined bedrock channels are within the steepened and narrow valleys composed of resistant granitic gneiss and show the evidence for recent bedrock incision processes. However, the unconfined bedrock channels are mainly within the broad and flat valleys of weak saprolites and limestone with high joint density have lower unit stream power and don't show any marker for bedrock incision. In conclusion, high-relief landscape mainly composed of more resistant rocks generates steep and narrow valleys, which leads to the formation of continuous and actively incising bedrock channels. However, low-relief landscape underlain by non-resistant rocks shows wider and lower-gradient channels, with intermittent bedrock channels due to locally more resistant rock bodies.</p> </div>

scholarly journals Complementary mesoscale dynamics of spectrin and acto-myosin shape membrane territories during mechanoresponse

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Andrea Ghisleni ◽  
Camilla Galli ◽  
Pascale Monzo ◽  
Flora Ascione ◽  
Marc-Antoine Fardin ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Cell Adhesion ◽  
Membrane Trafficking ◽  
Cell Mechanics ◽  
Membrane Skeleton ◽  
The Other ◽  
Cell Cortex ◽  
Dynamic Interactions ◽  
Mesoscale Dynamics ◽  
Dynamic Interplay

Abstract The spectrin-based membrane skeleton is a major component of the cell cortex. While expressed by all metazoans, its dynamic interactions with the other cortex components, including the plasma membrane or the acto-myosin cytoskeleton, are poorly understood. Here, we investigate how spectrin re-organizes spatially and dynamically under the membrane during changes in cell mechanics. We find spectrin and acto-myosin to be spatially distinct but cooperating during mechanical challenges, such as cell adhesion and contraction, or compression, stretch and osmolarity fluctuations, creating a cohesive cortex supporting the plasma membrane. Actin territories control protrusions and contractile structures while spectrin territories concentrate in retractile zones and low-actin density/inter-contractile regions, acting as a fence that organize membrane trafficking events. We unveil here the existence of a dynamic interplay between acto-myosin and spectrin necessary to support a mesoscale organization of the lipid bilayer into spatially-confined cortical territories during cell mechanoresponse.

scholarly journals Summer Water Temperatures in Alluvial and Bedrock Channels of the Olympic Peninsula

2009 ◽  
Vol 24 (2) ◽  
pp. 103-108 ◽  
Author(s):  
Mark A. Hunter ◽  
Timothy Quinn
Keyword(s):  
The Other ◽  
Low Flow ◽  
Olympic Peninsula ◽  
Channel Changes ◽  
Bedrock Channel ◽  
Stream Geomorphology ◽  
Alluvial Channel ◽  
Daily Water ◽  
The Individual ◽  
Bedrock Channels

Abstract To better understand how stream geomorphology may affect water temperature, we recorded water temperatures along two channels, one with deep alluvium and the other composed of bedrock and shallow alluvium. Study channels were located in managed forestlands on the Olympic Peninsula. Water temperatures were recorded hourly at 75-m intervals along 1.6 and 1.4 km of the alluvial and bedrock channels, respectively, during the summers of 2003 and 2004. Seasonal maximum and minimum daily water temperatures (i.e., season-long means for individual temperature dataloggers) in the alluvial channel tended to vary less over the course of the summer than temperatures in the bedrock channel. In addition, the means of all the individual dataloggers' daily maximums for each stream (reach mean maximum) and, similarly, the daily minimums (reach mean minimum) varied less for the alluvial channel. Changes in temperature from the upstream to downstream were greater for the bedrock channel, but only at low flow.

scholarly journals Managing clastic reservoir heterogeneity I: Sedimentology and sequence stratigraphy of the Late Triassic Minjur Sandstone at the Khashm al Khalta type locality, Central Saudi Arabia

GeoArabia ◽  
2012 ◽  
Vol 17 (2) ◽  
pp. 17-56 ◽  
Author(s):  
Benoît Issautier ◽  
Yves-Michel Le Nindre ◽  
Abdullah Memesh ◽  
Saleh Dini ◽  
Sophie Viseur
Keyword(s):  
Sequence Stratigraphy ◽  
Depositional Environments ◽  
Coarse Grained ◽  
Late Triassic ◽  
Fluvial Systems ◽  
Remarkable Case ◽  
Sand Bars ◽  
Fluvial Environments ◽  
Maximum Flooding Surface

ABSTRACT The Late Triassic (Norian–Rhaetian) Minjur Sandstone provides a remarkable case study for understanding and modelling the spatial distribution of sand bodies in a fluvial-deltaic system. As such it has been studied in connection with the geological storage of CO2 in complex heterogeneous formations. Detailed sedimentological mapping of the formation’s vertical and lateral variations in and around the type section at Khashm al Khalta (Khashm al Minjur), which is the area of interpreted maximum inlet/outlet activity, has provided a relatively detailed picture of the sequence stratigraphy. As originally described, shallow-marine flooding with the development of tidal mud flats and carbonate facies occurred near the middle of the formation, splitting it into a lower member dominated by subtidal, brackish and scattered fluvial environments, and an upper member marked by the appearance of meandering point bars capped upward by very proximal deposits forming thick (20 m) coarse-grained sandstone bars that can be followed over several kilometers. The general trend at formation scale is thus upward thickening and coarsening sedimentation related to an increasing clastic influx and the development of fluvial systems, with the fluvial upper member being dominated by amalgamated sand bars. The sequence stratigraphy indicates nine depositional sequences involving four depositional environments: sabkha, tidal, estuarine and fluvial-continental. The lower Minjur is a transgressive tract of four sequences of which Sequence 4 reflects maximum flooding and correlates with maximum flooding surface (MFS) Middle Norian Tr80. Sequence 5 corresponds to a meander system at the base of the upper Minjur, and is followed by sequences 6 to 9 reflecting an increasing clastic influx generating amalgamated coarse-grained bars. The upper Minjur thus represents a highstand systems tract.

scholarly journals El Césped del Vecino es más Verde: Flora de Patios a Través de un Gradiente Social

2015 ◽  
Vol 8 (Ed.esp.) ◽  
pp. 159
Author(s):  
Fábio Angeoletto ◽  
Juan Pedro Ruiz Sanz ◽  
Frederico Fonseca Da Silva ◽  
Ricardo Massulo Albertin ◽  
Aline Pradeiczuk ◽  
...  
Keyword(s):  
Food Security ◽  
Biodiversity Conservation ◽  
Plant Diversity ◽  
Metropolitan Area ◽  
Biological Diversity ◽  
Diversity Indices ◽  
The Other ◽  
Woody Vegetation ◽  
Endangered Plant ◽  
Considerable Potential

Patios urbanos tienen un potencial considerable para la conservación de la biodiversidad y refuerzo de la seguridad alimentaria. Sin embargo, estos espacios no están bien planificados, existe poca información sobre la diversidad de la flora presente en los patios de las diferentes clases sociales. Hemos cuantificado y comparado la diversidad vegetal de los patios de dos barrios de la región metropolitana de Maringá, mediante el cálculo de índices de diversidad, correlaciones bivariadas y del potencial de plantíos, y trazamos directrices de planificación, con el objetivo de aumentar la presencia de la vegetación arbórea, fortalecer la seguridad alimentaria y contribuir a la conservación de la diversidad biológica, incluyéndose la preservación de especies de plantas en peligro de extinción. The Grass is Always Greener on the Other Side of the Fence: Flora of Backyards Through a Social Gradient Urban backyards have considerable potential for biodiversity conservation and the enhancement of food security. However, these spaces are poorly planned, there is little information on the diversity of flora present in the backyards of different social clases. We quantified and compared plant diversity of the backyards of two neighborhoods in the metropolitan area of ​​Maringa, by calculating diversity indices, bivariate correlations, the planting potencial, and outline planning guidelines, with the goal of increasing the presence of woody vegetation, strengthen the food security and contribute to the conservation of biological diversity, including the preservation of endangered plant species. KEYWORDS: Urban Ecology, Backyards, Biodiversity, Food Security

Fluvial geomorphology of Indian rivers: an overview

2002 ◽  
Vol 26 (3) ◽  
pp. 400-433 ◽  
Author(s):  
Vishwas S. Kale
Keyword(s):  
Fluvial Geomorphology ◽  
Sediment Load ◽  
Dynamic Environment ◽  
Alluvial Channels ◽  
Indian Peninsula ◽  
Behavioural Characteristics ◽  
Extreme Variability ◽  
Channel Patterns ◽  
Bedrock Channels ◽  
Large Floods

The rivers of India reveal certain special characteristics because they undergo large seasonal fluctuations in flow and sediment load. The rivers are adjusted to an array of discharges, and most rivers exhibit morphologies that are related to high-magnitude floods. In the last 100 years primarily hydraulic engineers have contributed to the understanding of the fluvial forms and processes. Though this trend has continued even today, in recent decades some interesting fluvial research has also been carried out by earth scientists. Four large rivers, namely Brahmaputra, Kosi, Indus and Narmada, have received greater attention from fluvial geomorphologists. The major themes in Indian fluvial geomorphology include the hydrology of monsoonal rivers; forms and processes in alluvial channels; causes of avulsion, channel migration; and anomalous variations in channel patterns; dynamics of suspended sediment; and the geomorphic impacts of floods. Studies of bedrock channels are far less than similar studies in alluvial channels. Only a few rivers have been investigated in this respect. Studies indicate that the Himalayan rivers are different in many respects from those of the Indian Peninsula. The former occupy a highly dynamic environment with extreme variability in discharge and sediment load. Earthquakes and landslides also have a great impact on these rivers from time to time. Consequently, the rivers are characterized by frequent changes in shape, size, position and planform. In comparison, the adjustments in Peninsular rivers are less frequent and of a much smaller magnitude. An inescapable conclusion is that in the tropical monsoonal environment, large floods are important geomorphic agents that temporarily affect the forms and behavioural characteristics of some rivers, but leave a lasting effect on others. In magnitude-frequency terms, large floods are major formative events in many rivers of the Indian region in general and the Indian Peninsula in particular.

The Ecology and Management of Wood in World Rivers

2003 ◽  
Keyword(s):  
Riparian Forest ◽  
Wood Structures ◽  
Fluvial Systems ◽  
South Wales ◽  
The World ◽  
Natural Wood ◽  
Bank Stabilization ◽  
World Rivers ◽  
Fluvial Environments ◽  
River Valleys

<em>Abstract.</em>—Wood induces hydraulic, morphologic, and textural complexity into fluvial systems in forested regions around the world. Snags and logjams can create complex networks of channels and wetlands across entire river valleys and historically posed a significant obstacle to navigation. The clearing of wood from channels and riparian forest land reduced or eliminated the quantity and supply of wood into rivers in many regions of the world. Ecological restoration of fluvial environments increasingly includes the placement of wood. But few guidelines exist on appropriate methods for emulating natural wood accumulations, where and how to place wood, its longevity, the hydraulic and geomorphic consequences of wood, and how to manage systems where wood is reintroduced. Important factors to understand when placing wood in rivers include the watershed and reach-scale context of a project, the hydraulic and geomorphic effects of wood placements, possible changes in wood structures over time, and how it may impact human infrastructure and safety. Engineered logjams constructed in Washington, USA and New South Wales, Australia offer examples of how wood reintroduction can be engineered without the use of artificial anchoring to form stable instream structures as part of efforts to rehabilitate fluvial ecosystems and provide ecologically sensitive means to treat traditional problems such as bank stabilization and grade control.

Sign in / Sign up

Export Citation Format

Share Document