scholarly journals Spatial variability in channel and slope morphology within the Ardennes Massif, and its link with tectonics

2010 ◽  
Vol 7 (5) ◽  
pp. 6981-7006 ◽  
Author(s):  
N. Sougnez ◽  
V. Vanacker

Abstract. Geomorphic processes that produce and transport sediment, and incise river valleys are complex; and often difficult to quantify over longer timescales of 103 to 105 years. Morphometric indices that describe the topography of hill slopes, valleys and river channels have commonly been used to compare morphological characteristics between catchments and to relate them to hydrological and erosion processes. This work focuses on a wide range of slope and river channel morphometric indices to study their behavior and strength in regions affected by low to moderate tectonic activity. We selected 10 catchments of about 150 to 250 km2 across the Ardennes Massif that cover various tectonic domains with uplift rates ranging from about 0.06 to 0.20 mm year−1 since mid-Pleistocene times. The morphometric analysis indicates that the slope and channel morphology of third-order catchments is not yet in topographic steady-state, and exhibits clear convexities in slope and river profiles. Our data indicate that the fluvial system is the main driver of topographic evolution and that the spatial pattern of uplift rates is reflected in the distribution of channel steepness and convexity. The spatial variation that we observe in slope and channel morphology between the 10 third-order catchments suggests that the response of the fluvial system was strongly diachronous, and that a transient signal of adjustment is migrating from the Meuse valley towards the Ardennian headwaters.

2011 ◽  
Vol 15 (4) ◽  
pp. 1095-1107 ◽  
Author(s):  
N. Sougnez ◽  
V. Vanacker

Abstract. Geomorphic processes that produce and transport sediment, and incise river valleys are complex; and often difficult to quantify over longer timescales of 103 to 105 y. Morphometric indices that describe the topography of hill slopes, valleys and river channels have commonly been used to compare morphological characteristics between catchments and to relate them to hydrological and erosion processes. This study aims to analyze the link between tectonic uplift rates and landscape morphology based on slope and channel morphometric indexes. To achieve this objective, we selected 10 catchments of about 150 to 250 km2 across the Ardennes Massif (a Palaeozoic massif of NW Europe, principally located in Belgium) that cover various tectonic domains with uplift rates ranging from about 0.06 to 0.20 mm yr−1 since mid-Pleistocene times. The morphometric analysis indicates that the slope and channel morphology of third-order catchments is not yet in topographic steady-state, and exhibits clear convexities in slope and river profiles. Our analysis indicates that the fluvial system is the main driver of topographic evolution and that the spatial pattern of uplift rates is reflected in the distribution of channel steepness and convexity. The spatial variation that we observe in slope and channel morphology between the 10 third-order catchments suggests that the response of the fluvial system was strongly diachronic, and that a transient signal of adjustment is migrating from the Meuse valley towards the Ardennian headwaters.


2021 ◽  
Vol 13 (11) ◽  
pp. 2233
Author(s):  
Rasa Janušaitė ◽  
Laurynas Jukna ◽  
Darius Jarmalavičius ◽  
Donatas Pupienis ◽  
Gintautas Žilinskas

Satellite remote sensing is a valuable tool for coastal management, enabling the possibility to repeatedly observe nearshore sandbars. However, a lack of methodological approaches for sandbar detection prevents the wider use of satellite data in sandbar studies. In this paper, a novel fully automated approach to extract nearshore sandbars in high–medium-resolution satellite imagery using a GIS-based algorithm is proposed. The method is composed of a multi-step workflow providing a wide range of data with morphological nearshore characteristics, which include nearshore local relief, extracted sandbars, their crests and shoreline. The proposed processing chain involves a combination of spectral indices, ISODATA unsupervised classification, multi-scale Relative Bathymetric Position Index (RBPI), criteria-based selection operations, spatial statistics and filtering. The algorithm has been tested with 145 dates of PlanetScope and RapidEye imagery using a case study of the complex multiple sandbar system on the Curonian Spit coast, Baltic Sea. The comparison of results against 4 years of in situ bathymetric surveys shows a strong agreement between measured and derived sandbar crest positions (R2 = 0.999 and 0.997) with an average RMSE of 5.8 and 7 m for PlanetScope and RapidEye sensors, respectively. The accuracy of the proposed approach implies its feasibility to study inter-annual and seasonal sandbar behaviour and short-term changes related to high-impact events. Algorithm-provided outputs enable the possibility to evaluate a range of sandbar characteristics such as distance from shoreline, length, width, count or shape at a relevant spatiotemporal scale. The design of the method determines its compatibility with most sandbar morphologies and suitability to other sandy nearshores. Tests of the described technique with Sentinel-2 MSI and Landsat-8 OLI data show that it can be applied to publicly available medium resolution satellite imagery of other sensors.


Author(s):  
Valeriy Demidov ◽  
Oleg Makarov

The monograph summarizes the information over the past 20 years on the currently widely used. The textbook is intended for students of higher educational institutions, studying in the specialty of soil science, as well as specializing in erosion and soil protection. The textbook describes the physical basis and mechanism of erosion processes, based on some sections of hydraulics, hydrology, hydro-and aeromechanics, knowledge of which is necessary to understand the mechanism of water, wind and irrigation soil erosion. The main mathematical models and principles of forecasting the values of soil losses as a result of erosion processes are considered. The textbook will be useful not only for students and postgraduates studying in the specialty of soil science, but also for geographers, ecologists and a wide range of specialists interested in the problems of soil cover conservation and environmental protection.


Water ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2221
Author(s):  
Qihua Ran ◽  
Feng Wang ◽  
Jihui Gao

Rainfall patterns and landform characteristics are controlling factors in runoff and soil erosion processes. At a hillslope scale, there is still a lack of understanding of how rainfall temporal patterns affect these processes, especially on slopes with a wide range of gradients and length scales. Using a physically-based distributed hydrological model (InHM), these processes under different rainfall temporal patterns were simulated to illustrate this issue. Five rainfall patterns (constant, increasing, decreasing, rising-falling and falling-rising) were applied to slopes, whose gradients range from 5° to 40° and projective slope lengths range from 25 m to 200 m. The rising-falling rainfall generally had the largest total runoff and soil erosion amount; while the constant rainfall had the lowest ones when the projective slope length was less than 100 m. The critical slope of total runoff was 15°, which was independent of rainfall pattern and slope length. However, the critical slope of soil erosion amount decreased from 35° to 25° with increasing projective slope length. The increasing rainfall had the highest peak discharge and erosion rate just at the end of the peak rainfall intensity. The peak value discharges and erosion rates of decreasing and rising-falling rainfalls were several minutes later than the peak rainfall intensity.


Author(s):  
Cristina ZEPA ZEPA CORADINI ◽  
Valeriu TABÄ‚RÄ‚ ◽  
Doru PETANEC ◽  
Lavinia MICU ◽  
Irina PETRESCU ◽  
...  

Marigolds have an important economic value which let to an increase production and cultivation being thus used in a wide range of fields. One of the basic elements regarding marigolds production is represented by anthodia with flowers and seeds determined by the blossom and the number of anthodium on the plant. The plant’s blossom is determined by the n umber of lingulate flowers from the external side of the anthodium where seeds grow. Calendula is a polymorphic species, forming during its evolution not only flowering, but also semi-flowering anthodia and simple flowers. In the experimental field of UASVM Timisoara we performed a series of research regarding the morphological features of six local population of marigold from the western part of the country. Flowers’ blooming proved to have a different evolution due to the influence manifested by the local population and also by the harvest results. This blooming phenomenon proved to highly influence the production elements. Blooming influence upon anthodia mass of seeds proved to be as similar as in case of anthodia with flowers. At the beginning of the harvest period, the anthodia mass of seeds proved to be maxim. According to the information collected during research, anthodia flowering fails to reestablish during harvest. The flowering process influences the number and the size of the seeds. Moreover, flowers blooming process may lead to the formation of homogenous seeds, not only in size, but also as regards their morphological aspect. The seeds from the flowering anthodia proved to be homogenous in comparison with other anthodia and had even better technological qualities.


Author(s):  
O. P. Yermolaev ◽  
V. N. Golosov ◽  
M. V. Kumani ◽  
L. F. Litvin ◽  
I. I. Rysin ◽  
...  

Abstract. Quantitative assessments of soil loss from cultivated land and sediment redistribution along pathways from cultivated fields to river channels have been undertaken using a range of different methods and techniques, including erosion models, detailed studies of sediment redistribution in representative catchments, monitoring of gully head retreat and evaluation of sediment deposition in ponds and small reservoirs. Most of the sediment eroded from arable land is deposited between the lower portions of the cultivated slopes and the river channels. Less than 15% of the eroded sediment is delivered to the river channels. Sediment redistribution rates in the upper parts of the fluvial system have declined during the last 25 years in both the western and eastern parts of the Russian Plain, because of a major reduction of surface runoff during snowmelt and a reduction of the area of arable land in some parts of the study area.


Author(s):  
Anil Gill ◽  
Akash John ◽  
Neelam Iqbal ◽  
Tallat Anwar Faridi ◽  
Sofia Noor

Bakery items are a vital element of a well-balanced diet, and supermarket shelves now stock a wide range of them. Bakery items are the most popular ready-to-eat foods (REF).Objective:To assess the microbial quality of bakery foods (Bread, Cake and patties) and check the total plate count (TPC), bacterial and yeast count Methods:The analysis of the microbial quality of bakery products was determined for three different bakery products (bread, cake and patties) at ten different locations collected from a renowned bakery in Lahore, Pakistan. The samples were assessed under complete hygienic conditions by standardized plate count (TPC) and MPN method. Micro-organisms (Coliform, Fecal Coliform and Yeast) were lately confirmed by their morphological characteristics and biochemical tests Results: Among the three commodities, bread was found to be highly contaminated by micro-organisms and the total plate count recorded was 4.7 x 105cfu g-1collected from sector I9 which is not consumable. Whereas Patties showed the number of TPC as 1.6 x 105 cfu g-1also collected from sector I9. Cake was revealed as least infected bakery product i.e., 5.7 x 104 cfu g-1. The above results showed that sector I9 is highly contaminated and a threat for health. Bacterial plate count (Coliform and Fecal Coliform count) was highly measured in bread as 460 MPN g-1 taken from sector I5 where as it remains under the permissible limit determined by WHO, 1994 in remaining sectors Conclusions:In conclusion the bakery food is contaminated by the use of un-hygienic water, miss handled during the process after baking i.e., slicing, serving and packaging. To avoid a possible epidemic of food borne illness, competent authorities should conduct a stricter and more stringent inspection of  REFs sold to clients in bakeries.


Author(s):  
Roberto Maciel-Flores ◽  
José Rosas-Elguera ◽  
Laura Peña-García ◽  
Celia Robles-Murguía

Conserving the geological heritage in Jalisco implies, identifying, classifying and substantiating the importance of geosites in Jalisco and its subsequent dissemination through geotourism. The above can contribute to the creation of geo-park (s), according to the definition and methodology of UNESCO, with the consequent economic benefit to the inhabitants of these regions. The disclosure of geological information encourages an appreciation and care of abiotic resources (rocks, minerals, fossils, morphology, soil and water), especially prior to productive activities, minimizing their damage or avoiding building in areas with geological hazards. Jalisco has a great geodiversity, compared to other states, its history begins approximately 200 million years ago, recorded in the Sierra Madre del Sur and in the Jalisco Block, the most recent volcanic and tectonic activity is recorded in the Volcanic Belt Mexican. The previous provinces, together with the Sierra Madre Occidental and the Central Plateau, contain a wide range of rocks, fossil areas of economic and cultural importance (most of 70 places) and relate the geological history and its dynamics. Geothermal activity, is present in 400 locations.


2009 ◽  
Vol 13 (02) ◽  
pp. 275-282 ◽  
Author(s):  
Ning Sheng ◽  
Jing Sun ◽  
Yongzhong Bian ◽  
Jianzhuang Jiang ◽  
Dong Xu

Novel heteropentameric porphyrins-pyrene arrays, in which four meso-tetraphenyl porphyrins are linked to the center unit of pyrene by four acetylenyl bonds, were designed and synthesized. The newly synthesized heteropentameric compounds have been characterized by a wide range of spectroscopic methods. The third-order nonlinear optical (NLO) properties of both the metal-free and zinc compounds of the three-dimensional arrays were investigated by Z-scan experiments, showing enhanced NLO properties compared with that of the porphyrin and pyrene monomers.


2014 ◽  
Vol 47 (1) ◽  
pp. 384-390 ◽  
Author(s):  
Martin Etter ◽  
Robert E. Dinnebier

Parametric refinement is used for the simultaneous modeling of a series of diffraction data, replacing single independent parameters with physical or empirical equations that are valid for the full sequence of data. For the parametric treatment of diffraction data at high pressure, pressure-dependent constraints can be introduced in the form of an equation of state (EoS). However, the parameterization needs inverse functions of the EoS and most of them are not analytically invertible. In order to overcome this drawback, Taylor series expansions of different orders of the Vinet EoS were calculated and analytically inverted. It is shown that the inverted third-order Vinet EoS approximation, in its volume and linearized version, is applicable to a wide range of materials under high pressure.


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