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Journal articles on the topic 'Concave landforms'
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1
Gomes, João Henrique Gaia, Marcos Gervasio Pereira, Fabiana da Costa Barros, Cristiane Figueira da Silva, Vanessa Aparecida Freó, and Alexandre dos Santos Medeiros. "Edaphic attributes in pedoforms of gullies, in the Southeast region of Brazil." Revista em Agronegócio e Meio Ambiente 14, no. 4 (2021): 1–13. http://dx.doi.org/10.17765/2176-9168.2021v14n4e7687.
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Water erosion acts as the main form of soil degradation, promoting the release of particles that associated with factors such as climate, relief, soil vegetation and use and occupation favor this process. This study aimed to evaluate whether gullies are more likely to be present in a specific type of landform and how physical and chemical soil characteristics vary between the internal and external environments of concave and convex gullies. The study was performed in the Cachimbal River sub-basin, Pinheiral (RJ). Gullies were mapped and the quantitative and qualitative evaluations (occurrence in concave or convex surface). For each type of landform, one gully was selected. Soil samples (disturbed and undisturbed) were collected from the internal and external surfaces of each gully at a depth of 0-10 cm and soil chemical and physical characteristics were determined. More gullies were present in convex landforms and differences in soil characteristics were observed between the internal and external gully surfaces, but not between different landforms. Ca+2, S value, H+Al, T value, Mg+2, TOC and K+ were associated with the external surface, and P, Al+3, aluminum saturation, V%, and pH with the internal surface. Natural and total clay content, and soil and particle density were the physical characteristics associated with the external surface, and total and fine sand content, porosity, degree of flocculation, and silt content with the internal surface.
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Gudowicz, Joanna, and Renata Paluszkiewicz. "MAT: GIS-Based Morphometry Assessment Tools for Concave Landforms." Remote Sensing 13, no. 14 (2021): 2810. http://dx.doi.org/10.3390/rs13142810.
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The rapid development of remote sensing technology for obtaining high-resolution digital elevation models (DEMs) in recent years has made them more and more widely available and has allowed them to be used for morphometric assessment of concave landforms, such as valleys, gullies, glacial cirques, sinkholes, craters, and others. The aim of this study was to develop a geographic information systems (GIS) toolbox for the automatic extraction of 26 morphometric characteristics, which include the geometry, hypsometry, and volume of concave landforms. The Morphometry Assessment Tools (MAT) toolbox in the ArcGIS software was developed. The required input data are a digital elevation model and the form boundary as a vector layer. The method was successfully tested on an example of 21 erosion-denudation valleys located in the young glacial area of northwest Poland. Calculations were based on elevation data collected in the field and LiDAR data. The results obtained with the tool showed differences in the assessment of the volume parameter at the average level of 12%, when comparing the field data and LiDAR data. The algorithm can also be applied to other types of concave forms, as well as being based on other DEM data sources, which makes it a universal tool for morphometric evaluation.
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Haeberli, Wilfried, Lukas U. Arenson, Julie Wee, Christian Hauck, and Nico Mölg. "Discriminating viscous-creep features (rock glaciers) in mountain permafrost from debris-covered glaciers – a commented test at the Gruben and Yerba Loca sites, Swiss Alps and Chilean Andes." Cryosphere 18, no. 4 (2024): 1669–83. http://dx.doi.org/10.5194/tc-18-1669-2024.
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Abstract. Viscous-flow features in perennially frozen talus/debris called rock glaciers are being systematically inventoried as part of the global climate-related monitoring of mountain permafrost. In order to avoid duplication and confusion, guidelines were developed by the International Permafrost Association to discriminate between the permafrost-related landform “rock glacier” and the glacier-related landform “debris-covered glacier”. In two regions covered by detailed field measurements, the corresponding data- and physics-based concepts are tested and shown to be adequate. Key physical aspects which cause the striking morphological and dynamic differences between the two phenomena/landforms concern the following: tight mechanical coupling of the surface material to the frozen rock–ice mixture in the case of rock glaciers, contrasting with essential non-coupling of debris to the glaciers they cover; talus-type advancing fronts of rock glaciers exposing fresh debris material from inside the moving frozen bodies, as opposed to massive surface ice exposed by increasingly rare advancing fronts of debris-covered glaciers; and increasing creep rates and continued advance of rock glaciers as convex landforms with structured surfaces versus predominant slowing down and disintegration of debris-covered glaciers as often concave landforms with primarily chaotic surface structure. Where debris-covered surface ice is or has recently been in contact with thermally controlled subsurface ice in permafrost, complex conditions and interactions can develop morphologies beyond simple either–or-type landform classification. In such cases, the remains of buried surface ice mostly tend to be smaller than the lower size limit of “glaciers” as the term is applied in glacier inventories and to be far thinner than the permafrost in which they are embedded.
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Mendonça, Victória Maria Monteiro, Gilsonley Lopes Santos, Marcos Gervasio Gervasio Pereira, and Carlos Eduardo Gabriel Menezes. "LITTER CONTRIBUTION ON DIFFERENT GEOMORPHOLOGICAL CONDITIONS IN THE ATLANTIC FOREST – STATE OF RIO DE JANEIRO, BRAZIL." FLORESTA 49, no. 3 (2019): 373. http://dx.doi.org/10.5380/rf.v49i3.51657.
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The deposition of leaf litter on the forest floor is influenced by biotic and abiotic factors where forest fragments are inserted, which is a major source of nutrients to the soil. The objective of this study was to evaluate the influence of the change in relief conditions (landform) in leaf litter contribution and nutrient content in a Submontane Seasonal Semi-deciduous Forest in Pinheiral (state of Rio de Janeiro, Brazil). It was selected two adjacent landforms with convex and concave relief type and they divided into small sites (SS), obeying the variation of the slope and topographic gradient. Five conic collectors with an area of 0.2834 m² were installed in each SS, totaling 30 collectors. The collections of leaf litter were carried out every 30 days during a year. The material retained in the traps was separated as the fractions; leaves, twigs, reproductive and other material to assess the proportion of each fraction in the leaf litter production and nutrient content of the fraction leaves. The contribution and nutrient content of litter are influenced by the type of landform and seasons of the year. The highest contribution was observed in the dry season, in the lower and middle SS of the landforms, and the highest nutrient levels occurred in the convex landform during the rainy season.
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Lima, Julião Soares de Souza, Samuel Assis Silva, Daniel Pena Pereira, and Marcelo Soares Altoé. "PROBABILITY OF PARTICLE-SIZE FRACTIONS OCCURRENCE IN DIFFERENT LANDFORMS." REVISTA ENGENHARIA NA AGRICULTURA - REVENG 26, no. 4 (2018): 352–59. http://dx.doi.org/10.13083/reveng.v26i4.823.
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Knowing the variation of particle-size fractions, considering the relief forms, contributes for understanding the variation of other soil attributes. This work aimed to study the spatial distribution of the probability of particle-size fractions occurrence (clay, silt, very fine sand, fine sand, coarse sand, and total sand) in a clayey Oxisol with predominance of concave and convex curvatures. A sampling grid with 94 sampling points in 33x33m spacing at a depth of 0–0.20 m was built using a GPS. The spatial analysis was performed through indicator kriging. The spherical model was fit for all soil fractions, with ranges varying from 130 m to 280 m. In the region of convex curvature, the clay fraction presented the highest probability of occurrence (0.75 to 1.00), whereas in the concave region the coarse sand and total sand fractions presented the highest probability of occurrence. The very fine sand fraction and the silt did not present pattern of distribution in relation to the dominant curvatures of the relief.
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Sacramento, José Augusto Amorim Silva do, Ana Caroline de Moraes Araújo, Maria Eugenia Ortiz Escobar, Francisco Alisson da Silva Xavier, Ana Clara Rodrigues Cavalcante, and Teógenes Senna de Oliveira. "Soil carbon and nitrogen stocks in traditional agricultural and agroforestry systems in the semiarid region of Brazil." Revista Brasileira de Ciência do Solo 37, no. 3 (2013): 784–95. http://dx.doi.org/10.1590/s0100-06832013000300025.
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In the semiarid region of Brazil, inadequate management of cropping systems and low plant biomass production can contribute to reduce soil carbon (C) and nitrogen (N) stocks; therefore, management systems that preserve C and N must be adopted. This study aimed to evaluate the changes in soil C and N stocks that were promoted by agroforestry (agrosilvopastoral and silvopastoral) and traditional agricultural systems (slash-and-burn clearing and cultivation for two and three years) and to compare these systems with the natural Caatinga vegetation after 13 years of cultivation. The experiment was carried out on a typical Ortic Chromic Luvisol in the municipality of Sobral, Ceará, Brazil. Soil samples were collected (layers 0-6, 6-12, 12-20, 20-40 and 40-60 cm) with four replications. The plain, convex and concave landforms in each study situation were analyzed, and the total organic C, total N and densities of the soil samples were assessed. The silvopastoral system promoted the greatest long-term reductions in C and N stocks, while the agrosilvopastoral system promoted the smallest losses and therefore represents a sustainable alternative for soil C and N sequestration in these semiarid conditions. The traditional agricultural system produced reductions of 58.87 and 9.57 Mg ha-1 in the organic C and total N stocks, respectively, which suggests that this system is inadequate for these semiarid conditions. The organic C stocks were largest in the concave landform in the agrosilvopastoral system and in the plain landform in the silvopastoral system, while the total N values were highest in the concave landform in the native, agrosilvopastoral and silvopastoral systems.
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Baranowski, Jarosław, and Stanisław Kędzia. "Air temperature as a determinant of the forest line in the Tatras." Folia Forestalia Polonica 63, no. 3 (2021): 203–13. http://dx.doi.org/10.2478/ffp-2021-0021.
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Abstract The forest line has been widely studied by a number of scientists representing various research disciplines. Changes in its position are an indicator of climate change. However, despite numerous studies, it is not always known what has the greatest influence on the position of the forest line. In the Tatras, which are Alpine moun-tains, the position of the forest line in places not disturbed by human activity or slope processes mainly depends on the annual mean air temperature and the number of days with negative temperature and its value in the warm season. The most unfavourable thermal conditions are found at the bottoms of concave landforms, just above the forest line. This thermal barrier effectively limits the upward movement of the forest line, even if the average annual temperature increases. Small concave landforms may have a higher vertical temperature gradient and lower air temperature values at their bottoms than larger and higher-lying forms.
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Jarosław, Baranowski, and Kędzia Stanisław. "Air temperature as a determinant of the forest line in the Tatras." FOLIA FORESTALIA POLONICA, SERIES A – FORESTRY 63, no. 3 (2021): 203–13. https://doi.org/10.2478/ffp-2021-0021.
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The forest line has been widely studied by a number of scientists representing various research disciplines. Changes in its position are an indicator of climate change. However, despite numerous studies, it is not always known what has the greatest influence on the position of the forest line. In the Tatras, which are Alpine mountains, the position of the forest line in places not disturbed by human activity or slope processes mainly depends on the annual mean air temperature and the number of days with negative temperature and its value in the warm season. The most unfavourable thermal conditions are found at the bottoms of concave landforms, just above the forest line. This thermal barrier effectively limits the upward movement of the forest line, even if the average annual temperature increases. Small concave landforms may have a higher vertical temperature gradient and lower air temperature values at their bottoms than larger and higher-lying forms.
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Kruhlov, Ivan, Anatoliy Smaliychuk, and Yurii Svatko. "Hybrid delineation of landforms: Case of Bystrytsia-Pidbuzka drainage basin." PROBLEMS OF GEOMORPHOLOGY AND PALEOGEOGRAPHY OF THE UKRAINIAN CARPATHIANS AND ADJACENT AREAS, no. 17 (December 15, 2024): 148–59. https://doi.org/10.30970/gpc.2024.2.4563.
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Landforms, together with geological substrate and geomorphic processes, are essential for delineation of geoecosystems, which are indispensable for environmental management at landscape and regional levels. Geomorphometry is a geographic information system technology, which affords quantitative land-surface analysis and landform delineation using digital elevation models (DEM). Application of geomorphometry has been fostered by the emergence of free global high-resolution DEMs. However, automated geomorphometric extraction of landforms for flat areas, like wide river valleys, may be problematic owing to insufficient accuracy of the DEM. We selected the Bystrytsia-Pidbuzka drainage basin of 500 km², which has a transitional location between low flysch External Carpathian Mountains and wavy denudation-alluvial plains of the Fore-Carpathian Upland in Lviv Oblast (Ukraine), to test a hybrid methodology of landform delineation – manual and automated geomorphometric. We considered regional landforms as orotectonic units (morphostructures), which are used to characterize ecoregions, and morpholithotopes as the smallest local landforms – mesorelief elements together with surface deposits and current geomorphic processes. FABDEM V1-2 with a resolution of 30*30 m was used as a primary geodataset of elevation data. Ecoregions and morpholithotopes of wide flat valley bottoms were delineated via manual interpretation of the DEM and ancillary data, while the morpholithotopes of the hilly and mountainous interfluves were delineated automatedly using three topographic variables: topographic position index, slope, and flow accumulation. Within the study area, we singled-out six microecoregions and four mesoecoregions: Upper Dnister Depression, Upper Dnister Upland, Marginal Beskydy, and Dnister Beskydy. There are 21 classes of morpholithotopes distinguished belonging to flat valley bottoms with alluvial and lacustrine deposits, narrow valleys and big gullies, as well as lower concave and upper convex slopes formed by colluvial and eluvial-colluvial deposits respectively, divided into four inclination categories, and two lithological groups. Each morpholithotope class is attributed with a drainage status and probable current geomorphic processes. The obtained dataset is oriented on further ecological application. Key words: morpholithotope; ecoregion; geomorphometry; FABDEM; the Carpathian Mountains; the Fore-Carpathian Upland.
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Jeldes, Isaac A., Daniel C. Yoder, and Eric C. Drumm. "Sustainable Slopes: Satisfying Rainfall-Erosion Equilibrium and Mechanical Stability." Transactions of the ASABE 61, no. 4 (2018): 1323–33. http://dx.doi.org/10.13031/trans.12713.
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Abstract. While manmade slopes are traditionally constructed with planar cross-sections, natural stable slopes are usually curvilinear with significant concavity of the profile. This concavity occurs as a result of evolutionary processes in which rain-driven erosion and sediment transport are balanced through slope shape adjustments. At the point of equilibrium, a relatively steady concavity with a uniform erosion rate is observed over time. Nevertheless, a true equilibrium state is possible only if mechanical stability is satisfied. In this study, concave profiles in rainfall erosion equilibrium were found based on the principles of the well-known RUSLE2 model. Results showed the existence of a family of steady shapes satisfying the condition of uniform normalized erosion rate. Those steady concave shapes that also satisfied long-term mechanical stability were then investigated. The overall results suggest that concave slopes can be constructed to achieve both minimal steady-state erosion equilibrium and mechanical stability, leading to more natural and sustainable landforms with minimal sediment delivery during initial slope adjustments. Keywords: Concave slopes, Erosion, Sustainable design, Slope stability.
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Camacho Orozco, Sebastian, and Alfonso Mariano Ramos-Cañón. "Failure potential index for slopes conditioned by landforms." Boletín de Ciencias de la Tierra, no. 40 (July 1, 2016): 39–45. http://dx.doi.org/10.15446/rbct.n40.53658.
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The paper contributes to the understanding of the effect of three-dimensional landforms in the slope stability through to the analysis of nine models, which result from the combination of three different landforms in plant and profile view (straight, convex and concave). The analysis is based on the calculation of a failure potential indexwhich represent a unified way a stability value for each model. The procedure was performed by mean of finite element numerical simulations with a Mohr-Coulomb elastoplastic model applied to each geometry in homogeneous solis. We take into account permanent flow and partial saturation above of the flow surface within the slope. Finally, it is quantified the failure susceptibility of the nine models by mean of the assignation of a failure potential index. With this assignation, it is possible to stablish an order of priority of the susceptibility of the slopes in function of geomorphology of each model.
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Filipiak, Maciej. "Distribution of silver-fir (Abies alba Mill.) in the Sudeten Mts." Biodiversity: Research and Conservation, no. 3-4 (December 30, 2006): 294–99. https://doi.org/10.14746/biorc.2006.3-4.21.
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This paper presents the assessments concerning the vertical distribution, exposure, slope inclination and land relief of silver-fir localities. The current distribution of fir trees suggest that in the past, Abies alba was widespread in the Sudety Mts. at the altitude range 350-800 m. At altitudes of up to 800 m, the number of localities in each zone is often proportional to the total forest area in the zone. Above 800 m, fir trees are now very rare. The studied species is in general similarly frequent in localities with various exposure and degree of slope. It prefers concave landforms (valleys, concave slopes). It can be concluded that the studied species occurs in a wide range of habitats in the Sudeten Mts. This suggests that its withdrawing from the Sudetes is not of natural origin. Main cause of this process is related rather with strong interference of man in forest stand composition.
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Yang, Wu, Ning Yu, Mingxing Yang, Jun Yan, Min Zhang, and ShiQiang Yang. "Sustainable development of geological resources: the Characteristics of Red Karst Landscape and Tourism Development in Tongren, Guizhou." AIMS Geosciences 10, no. 1 (2024): 141–71. http://dx.doi.org/10.3934/geosci.2024009.
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<abstract> <p>China is rich in karst resources and famous for its karst landscape. As a part of karst, the popularity of red karst is obviously low and has received little attention; moreover, the related scientific research and tourism development are relatively immature. Therefore, this paper takes the red karst in Tongren, Guizhou as the research object, analyzes the characteristics and causes of the red karst, comprehensively evaluates its landscape value, and puts forward development strategies and protection suggestions. Through the above research, the following three research results are obtained. (1) On the basis of a field investigation and a literature review, the geographical situation, background, and landscape characteristics of the red karst landform and its surrounding areas in Tongren City were investigated in detail. It forms isolated peaks, rock walls, protruding rocks, stone pillars, and other forms. The most prominent features of the red karst landscape in Tongren City are that the color is red and white, and the shape is concave and convex in order. (2) Geochemical test and structural data collection and analyses of the collected samples were performed. The obtain concave layer rock is dolomitic limestone, and that convex lay rock is argillaceous dolomitic limestone. Because the convex layer rock sample is high in silicon element content, the convex layer rock sample is not easy to be weathered, is rich in clay mineral, and is not easy to be corrode; the convex layer rock sample gradually protrudes with the passage of time to form an uneven shape. The red karst landform is developed in either the rock stratum or tectonic zone with moderate tectonic deformation intensity. First, the formation of a single-layer honeycomb morphology requires that the rock stratum is subjected to a sufficient horizontal compressive stress at a certain burial depth. Second, it is necessary to widely exist in areas with relatively gentle rock formation occurrence; too strong of a structural deformation will make the rock formation occurrence steep, which is not conducive to the occurrence of differential dissolution between adjacent strata. (3) Through the construction of an evaluation index system, the red karst in Tongren City is evaluated, and it is concluded that the geological heritage value is high, and the development and utilization conditions are weak. The conclusion of this article is a supplement to the geological and geomorphological system characteristics of southern karst. From the perspective of world natural heritage, the study enriches the academic evidence of red karst and enables its exemplary role to be well played. From the perspective of the tourism development value, more people should be made aware of the diverse types of karst landforms, which provide experience and suggestions for the value of landforms, tourism resources, and tourism development in similar areas.</p> </abstract>
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Choudhury, Taniya. "An Overview of Geomorphological Mapping: A Case Study of Rimbi Chhu River Basin, Sikkim, India." Journal of Geography, Environment and Earth Science International 28, no. 3 (2024): 65–84. http://dx.doi.org/10.9734/jgeesi/2024/v28i3758.
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Geomorphology is the primary science which demonstrates the basic understanding and mapping of terrain features. A geomorphological map consists of scientific data and dynamic source of information on characteristics of landforms, their origin and evolution, which can be recorded in a map form. Basin hydrology also gets impacted by the terrain features of a basin as overland flow, stream flow and through flow is largely determined by the underneath surface. The configuration of the basin topography reflects the nature of the interaction between process and form. Profound understanding and in depth analysis of geomorphological features of a river basin can provide beneficial information for predicting, preventing and mitigating natural hazards; managing natural resources sustainably for future generation. Implementation of remote sensing and GIS techniques have fostered incredible improvements in landform recognition and accelerated the growth of geomorphological research. The river Rimbi Chhu has been selected as the study area in order to determine terrain configuration in relation with geomorphological features of the basin area. Visual representation of terrain (such as aspect, slope, channel networks, different river profiles, shaded relief and flow direction) and geomorphological (saddle, ridge line, convex-concave slope, rounded hills, fault for instance) derivatives is therefore illustrated, as well as a description of the challenges and crisis that can occur in this context.
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Brocard, Gilles, Jane K. Willebring, and Fred N. Scatena. "Shaping of topography by topographically-controlled vegetation in tropical montane rainforest." PLOS ONE 18, no. 3 (2023): e0281835. http://dx.doi.org/10.1371/journal.pone.0281835.
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Topography is commonly viewed as a passive backdrop on which vegetation grows. Yet, in certain circumstances, a bidirectional feedback may develop between the control of topography and the spatial distribution of vegetation and landform development, because vegetation modulates the erosion of the land surface. Therefore, if reinforcing feedbacks are established between erosion and land cover distribution over timescales relevant to landform development, then the interactions between vegetation and topography may create distinctive landforms, shaped by vegetation. We expose here a strong correlation between the spatial distribution of vegetation, erosion rates, and topography at a characteristic length scale of 102-103m (mesoscale topography) in the Luquillo Experimental forest (LEF) of Puerto Rico. We use high-resolution LiDAR topography to characterize landforms, satellite images to classify the vegetation into forest types, and in-situ produced cosmogenic 10Be in the quartz extracted from soils and stream sediments to document spatial variations in soil erosion. The data document a strong correlation between forest type and topographic position (hilltop vs. valleys), and a correlation between topographic position and 10Be-derived erosion rates over 103−104 years. Erosion is faster in valleys, which are mostly covered by monocot Palm Forest, and slower on surrounding hills mostly covered by the dicot Palo Colorado Forest. Transition from one forest type to the next occurs across a break-in-slope that separates shallowly convex hilltops from deeply concave valleys (coves). The break-in-slope is the consequence of a longer-lasting erosional imbalance whereby coves erode faster than hills over landscape-shaping timescales. Such a deepening of the coves is usually spurred by external drivers, but such drivers are here absent. This implies that cove erosion is driven by a process originating within the coves themselves. We propose that vegetation is the primary driver of this imbalance, soil erosion being faster under Palm forest than under Palo Colorado forest. Concentration of the Palm forest in the deepening coves is reinforced by the better adaptation of Palm trees to the erosive processes that take place in the coves, once these develop steep slopes. At the current rate of landscape development, we find that the imbalance started within the past 0.1–1.5 My. The initiation of the process could correspond to time of settlement of these mountain slopes by the Palm and Palo Colorado forests.
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Anjos, Paloma A. P., Victor F. Velázquez, José M. Azevedo Sobrinho, and Rodrigo F. Lucena. "Granite Weathering, Denudation Processes, and Associated Landforms in the Itu-Cabreúva Region, São Paulo, Brazil." European Journal of Environment and Earth Sciences 4, no. 3 (2023): 14–23. http://dx.doi.org/10.24018/ejgeo.2023.4.3.407.
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The Itu-Cabreúva region is located about 90 km northwest of the São Paulo city center. The geological setting is characterized by the expressive occurrence of Neoproterozoic granitic rocks. These intrusive rocks form large plutons that have given rise to flattened hills, valleys with concave-convex slopes, and superficial drainage systems. As part of this larger framework, several smaller landforms with unique appearances occur, which can be categorized into six groups: nubbin, boulder, balanced rock, castle koppie, cave, and minor form. Although these reliefs were formed under similar weathering conditions, the research results show that the physical properties of the lithology and the nature and density of the joints strongly influenced the shape and size of the blocks. These geoforms have exceptional scenic value and are situated in a geographically advantageous location for a range of educational and recreational activities that can be adapted to different levels of knowledge. The implementation of such proposals in the context of understanding the physical environment would result in a number of benefits, including (i) greater community involvement in the environment, (ii) valorization of the local landscape as a historical record of the planet's evolution, and (iii) improvement of urban geological risk prevention programs. Finally, these landforms are fascinating and offer conclusive evidence that can be observed on a wide range of scales, illustrating how the brittle deformation and magmatic fabric of the granite massifs influenced the development of the local landscape.
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Nikolova, Valentina, Veselina Gospodinova, and Asparuh Kamburov. "Impact of Data Processing and DTM Resolution on Determining of Small Erosional Landforms." IOP Conference Series: Earth and Environmental Science 906, no. 1 (2021): 012127. http://dx.doi.org/10.1088/1755-1315/906/1/012127.
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Abstract Small erosional landforms are characterised by a dynamics closely related to the occurrence and changes in precipitation and water flowing down the slopes. Triggered by water, the erosion processes are controlled by the other environmental conditions like slope gradient, lithology, land cover and land use. Studying the changes in the topography gives information about the spatiotemporal dynamics of erosion and can contribute to a more effective assessment of erosion susceptibility and mitigation measures at the earliest stage of the process development. Usually in the initial stages, the changes in the topography are hardly noticeable and using high resolution digital terrain models (DTMs) is of high importance. In this relation, the aim of the current research is to determine to what extent the resolution of the models influences the results of delineating the flow lines, rills and gullies. For this purpose, a terrain survey was carried out and data was acquired by UAS (uncrewed aerial system) DJI Phantom 4RTK. DTMs in horizontal resolution of 0.05, 0.1, 0.2, 0.5 and 1 m are created and analysed. Special attention is given to the analysis of surface curvature as an indicator for flow convergence and divergence. The research is done on a slope area covered mainly by grass and some rare bushes and trees. Despite the observed variations, the results show a general trend of decrease in the flow length with decreasing DTMs resolution. Considering the plan curvature and concave areas, the differences are smallest between the models with cell size 0.1 and 0.2 m.
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Nonglait, Jonestar Lyngdoh. "Morphometric Analysis of Umtung River Basin using GIS and Remote Sensing." Current World Environment 20, no. 1 (2025): 488–500. https://doi.org/10.12944/cwe.20.1.36.
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An investigation of morphometric parameter for the Umtung River basin, situated in Meghalaya, India, employing advanced GIS and remotely sensed data. Various morphometric parameters were quantified, including basin area (224.91 km²), length (24.32 km), perimeter (147.04 km), and drainage density (1.34 km/km²). With 255 streams overall, the research showed a clearly defined stream order system up to the fifth order. Key findings indicate that the basin exhibits low stream frequency (1.13 stream/km²) and a bifurcation ratio (Rb) averaging 4.03, suggesting a complex, interconnected hydrological system with significant tributary contributions. The sinuosity index (SI) of 1.32 indicates a moderately sinuous channel morphology. An extended basin shape that is advantageous for flood management is suggested by a low form factor (0.38) and elongation ratio (0.39). With a ruggedness number (Rn) of 1.18, a relief ratio (Rr) of 35.85, and a basin relief of 872 m, relief metrics show notable topographical diversity driven by tectonic activity and differential erosion. Hypsometric analysis indicates a mature landscape characterized by concave slopes, underscoring the erosion-dominated landforms formed over geological time.
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Pogorelov, Anatoly, Andrey Laguta, and Petr Netrebin. "Morphometric analysis of the bottom topography of a large valley reservoir during its evolution." InterCarto. InterGIS 29, no. 1 (2023): 465–81. http://dx.doi.org/10.35595/2414-9179-2023-1-29-465-481.
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Until now, the study of the morphology of the bottom of large reservoirs, subject to gradual siltation, received little attention. Morphometric descriptions of reservoirs are limited by the type, shape, altitude position, size of the bed, and the volume of water in them. The article presents the results of the analysis of the bottom relief of the Krasnodar Reservoir and the transformations of this relief for 2005–2021. The analysis was performed based on the materials of bathymetric surveys for the regulated volume of the reservoir on an area of 224 km2 with the construction of the corresponding digital relief models. The relief of the bottom of the reservoir is represented by flat areas of a flooded accumulative plain with prevailing slopes of about 0.2–0.4°, dissected by river channels of lower order tributaries. The transformation of the relief is caused by gradual siltation. The total volume of deposits for the specified area in 2005–2021 amounted to 127 million m3 with an average silt layer of 0.4 m. To describe the morphological properties of the bottom topography, we used geomorphometric techniques with the calculation of the BPI (Bathymetric Position Index) and the classification of mesoscale landforms based on it. For the bed, relief forms have been established related to three types of surfaces: flat (lower bank shelf), concave (depressions, deep depressions) and convex (reef crests, back reefs, mid-slope reefs). The constructed maps reflect the differentiated morphology of the bed surface, the evolution of landforms under conditions of continuous transformation of the basin, and also make it possible to judge the prevailing processes of morphogenesis. The coastal zone and the shallow part of the bed are the most complex in morphological terms. Here, along with reefs of different genesis, deep depressions and depressions in the form of underwater channels in advanced deltas can form on the accumulative shoal.
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Neff, Brian P., Donald O. Rosenberry, Scott G. Leibowitz, et al. "A Hydrologic Landscapes Perspective on Groundwater Connectivity of Depressional Wetlands." Water 12, no. 1 (2019): 50. http://dx.doi.org/10.3390/w12010050.
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Research into processes governing the hydrologic connectivity of depressional wetlands has advanced rapidly in recent years. Nevertheless, a need persists for broadly applicable, non-site-specific guidance to facilitate further research. Here, we explicitly use the hydrologic landscapes theoretical framework to develop broadly applicable conceptual knowledge of depressional-wetland hydrologic connectivity. We used a numerical model to simulate the groundwater flow through five generic hydrologic landscapes. Next, we inserted depressional wetlands into the generic landscapes and repeated the modeling exercise. The results strongly characterize groundwater connectivity from uplands to lowlands as being predominantly indirect. Groundwater flowed from uplands and most of it was discharged to the surface at a concave-upward break in slope, possibly continuing as surface water to lowlands. Additionally, we found that groundwater connectivity of the depressional wetlands was primarily determined by the slope of the adjacent water table. However, we identified certain arrangements of landforms that caused the water table to fall sharply and not follow the surface contour. Finally, we synthesize our findings and provide guidance to practitioners and resource managers regarding the management significance of indirect groundwater discharge and the effect of depressional wetland groundwater connectivity on pond permanence and connectivity.
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Olvmo, Mats, Karna Lidmar-Bergström, and Göran Lindberg. "The glacial impact on an exhumed sub-Mesozoic etch surface in southwestern Sweden." Annals of Glaciology 28 (1999): 153–60. http://dx.doi.org/10.3189/172756499781821869.
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AbstractAlong the northern part of the western coast of Sweden, the landscape is characterized by joint-aligned valleys with intervening rock hills. Precambrian bedrock is exposed over large areas and the Quaternary cover is mainly restricted to the bottom of narrow valleys. The well-exposed bedrock exhibits many glacial forms, but recently the major landforms have been interpreted as exhumed sub-Mesozoic etch forms. To gain insight into the relative roles of different processes in shaping the present forms, we studied a granite area where the rock hills contain fractures and narrow clefts with weathering forms and saprolite remnants. Marks of glacial erosion are found only in the upper parts of the clefts, where erosion by subglacial meltwater has exploited weathered preglacial sheeting structures to form furrows with concave cross profiles (p forms). On the summit surfaces, glacial erosion has been of greater importance, but the roche moutonnees found here are also structurally controlled. The main impact of glacial erosion is plucking on the order of tens of metres. Thus, landscapes labelled “areally scoured glacial terrain” can, at some locations, also be described as stripped and slightly incised etch surfaces.
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Çöltekin, A., V. Rautenbach, S. Coetzee, and T. Mokwena. "LANDFORM PERCEPTION ACCURACY IN SHADED RELIEF MAPS: A REPLICATION STUDY CONFIRMS THAT NNW LIGHTING IS BETTER THAN NW AGAINST THE RELIEF INVERSION EFFECT." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-4 (September 19, 2018): 101–6. http://dx.doi.org/10.5194/isprs-archives-xlii-4-101-2018.
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<p><strong>Abstract.</strong> Relief inversion effect is a perceptual phenomenon that leads to an inverted perception of convex and concave shapes. This perceptual inversion occurs in scenes where the shading/shadows act as the main depth cue. In visuospatial displays, such as shaded relief maps, the positioning of the shadows in the northern slopes, thus when light source placed broadly in south, mislead the cognitive system based on the ‘light from above prior’ assumption (Mamassian and Goutcher 2001). Thus, assuming the light must come from above, our mind creates an illusion, and we perceive the landforms incorrectly. To judge the 3D spatial relationships in terrain representations correctly, the relief inversion effect must be avoided. Cartographic convention against this effect is to place the light source at northwest (NW), whereas a recent study demonstrated that north-north-west (NNW), or even north yields more precise results (Biland and Çöltekin, 2016). Since this finding goes against decades of convention, to establish its validity further, we attempted replicating the results with a different sample in South Africa. In this paper, we present our findings, which broadly confirm that the NNW (or also N) is better than NW against the relief inversion effect.</p>
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Fagherazzi, Sergio, Luca Baticci, Christine M. Brandon, and Maria Cristina Rulli. "Bedrock erosion in subglacial channels." PLOS ONE 16, no. 9 (2021): e0253768. http://dx.doi.org/10.1371/journal.pone.0253768.
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The Labyrinth in the McMurdo Dry Valleys of Antarctica is characterized by large bedrock channels emerging from beneath the margin of Wright Upper Glacier. To study the morphodynamics of large subglacial channels cut into bedrock, we develop herein a numerical model based on the classical theory of subglacial channels and recent results on bedrock abrasion by saltating bed load. Model results show that bedrock abrasion in subglacial channels with pressurized flow reaches a maximum at an intermediate distance up-ice from the glacier snout for a wide range of sediment grain sizes and sediment loads. Close to the snout, the velocity is too low and the sediment particles cannot be mobilized. Far from the snout, the flow accelerates and sediment is transported in suspension, thus limiting particle impacts at the channel bottom and reducing abrasion. This non-monotonic relationship between subglacial flow and bedrock abrasion produces concave up bottom profiles in subglacial channels and potential cross-section constrictions after channel confluences. Both landforms are present in the bedrock channels of the Labyrinth. We therefore conclude that these geomorphic features are a possible signature of bedrock abrasion, rather than glacial scour, and reflect the complex interplay between transport rate, sediment load, and transport capacity in subglacial channels.
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Mendonça, Patrícia Gabarra, João Fernandes da Silva Júnior, Ismênia Ribeiro de Oliveira, et al. "SPATIAL UNCERTAINTY OF NUTRIENT LOSS BY EROSION IN SUGARCANE HARVESTING SCENARIOS." Revista Brasileira de Ciência do Solo 39, no. 4 (2015): 1181–89. http://dx.doi.org/10.1590/01000683rbcs20140432.
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The assessment of spatial uncertainty in the prediction of nutrient losses by erosion associated with landscape models is an important tool for soil conservation planning. The purpose of this study was to evaluate the spatial and local uncertainty in predicting depletion rates of soil nutrients (P, K, Ca, and Mg) by soil erosion from green and burnt sugarcane harvesting scenarios, using sequential Gaussian simulation (SGS). A regular grid with equidistant intervals of 50 m (626 points) was established in the 200-ha study area, in Tabapuã, São Paulo, Brazil. The rate of soil depletion (SD) was calculated from the relation between the nutrient concentration in the sediments and the chemical properties in the original soil for all grid points. The data were subjected to descriptive statistical and geostatistical analysis. The mean SD rate for all nutrients was higher in the slash-and-burn than the green cane harvest scenario (Student’s t-test, p<0.05). In both scenarios, nutrient loss followed the order: Ca>Mg>K>P. The SD rate was highest in areas with greater slope. Lower uncertainties were associated to the areas with higher SD and steeper slopes. Spatial uncertainties were highest for areas of transition between concave and convex landforms.
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Kuroki, Takahito. "Landform mapping of Okinoshima island and sea bed of Munakata city." Abstracts of the ICA 1 (July 15, 2019): 1–2. http://dx.doi.org/10.5194/ica-abs-1-199-2019.
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<p><strong>Abstract.</strong> Munakata city is compiling its city history now. Then, in March 2019, the natural environment part edition of "Umi, Yama, Kawa" is scheduled to be published. I had to do landform mapping of Okinoshima island and sea bed in this project. In this abstract, the geography of Okinoshima, the process of mapping and some of the results are described.</p><p>The Sacred Island of Okinoshima and Associated Sites in the Munakata Region was registered as a World Heritage in July 2017. Okinoshima island is located about 70 km northwest of Kyushu main island. The island consists of a steep cliff and gentle slope and the area of the plain is small. It consists of shale, quartz porphyry, and talus deposit.</p><p>Fig.1 shows the landscape of Okinoshima island from the south. The highest peak is Mt. Ichinotake, the rock on the left is Mikadobashira and the rock on the right is Tengu-iwa. There is a holy place, Okitsu-miya of Munakata Taisha at the foot of the island. Residents have unwritten taboos that forbid actions such as removing anything from the island, or revealing anything seen or heard there.</p><p>Maps of land and sea bed were made by various kinds of geographic information by using GIS. They are ground elevation map, slope map, relief map and 3D image. Fundamental geospatial data of GSI (Geospatial Information Authority of Japan), map information related to isobaths of JHA (Japan Hydrographic Association) and airborne laser scanner data of Munakata city are used as the geographic information.</p><p>Landform classification map was made by interpretation of each map and field survey. Classified landforms are crest， dissected valley，steep cliff，landslip lobe，talus cone， seaside and man-made land. Farthermore, geologic and topographic lineaments were interpreted.</p><p>Fig.2 shows the 3D image of Okinoshima from the east. It can be identified that the height of Okinoshima is about 340 m above the flat sea bed. The topography between Okinoshima and Koyajima under the sea surface, is a shallow flat table in the west side and a concave area inclining to the east in the east side. The shape of the set of islands is like a horseshoe-shaped caldera.</p><p>In this poster presentation, I would like to introduce that we can understand the landform and its formative process of Okinoshima where access is restricted from the analysis and reference of such maps by GIS.</p>
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Biswas, Mery, Adrija Raha, Soumyajit Mukherjee, and Vinit Shailesh Kotak. "Geomorphic Imprints of Active Tectonics of the Bikaner-Nagaur Petroliferous Rift Basin and its Surroundings (Western Rajasthan, India)." Journal of the Geological Society of India 100, no. 3 (2024): 377–90. http://dx.doi.org/10.17491/jgsi/2024/173844.
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Abstract Geology of sedimentary rift-basins require strong geomorphic input for a proper interpretation of active tectonics. Rift-related sedimentation took place in western Rajasthan of the Indian shield, which includes the Bikaner-Nagaur basin (BNB) and a few other adjacent basins. The sedimentation history of the BNB includes Proterozoic, Cambrian, Permo-Carboniferous and from Paleocene to the Recent. This study analyses river profiles with the best-fit curve (R2) model for the BNB and the surrounding regions. The research shows that the watershed 3 within the study area is most active tectonically, through which multiple faults and lineaments pass. Hypsometric Curves (HCs) of watersheds 1, 2 and 3 indicate that these watersheds are tectonically active. This inference is based on the concave profiles of HCs at the head, and convex profiles of HCs at the body and toe sections. Clustering of sixty segments (S) of the considered rivers based on linear-scale morphometric parameters, e.g., sinuosity index (SI), stream length gradient index (SL) and concavity (θ) enabled segment-wise comparison of river profiles with similar values. These segments were compared pair-wise, and Euclidean-based dissimilarity (dR) values were calculated between each such pair. The findings too imply that tectonic activeness exists in parts of watersheds 1, 2 and 3. The channel flow lines are controlled by faults/lineaments as per the micro-scale examination of the drainage network and faults/ lineaments analysis. Under structural control, nine major geomorphic units emerged with distinct erosional surfaces, denudational hillocks, dissected hills and inselbergs. Detailed geomorphic map with micro-scale studies revealed a slope retreat process that resulted in landforms viz., pediment, pediment slope and active flood plains.
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Łupikasza, Ewa, and Tadeusz Niedźwiedź. "Synoptic climatology of fog in selected locations of southern Poland (1966–2015)." Bulletin of Geography. Physical Geography Series 11, no. 1 (2016): 5–15. http://dx.doi.org/10.1515/bgeo-2016-0010.
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Abstract This paper investigates fog frequency in southern Poland in relation to various topography (concave and convex forms) and atmospheric circulation types. It also discusses long-term variability in the annual and seasonal number of days with fog. Daily information on fog occurrence was taken from three high quality synoptic stations representing various landforms: Kraków-Balice (bottom of the hollow), Katowice-Muchowiec (Silesian Upland) and Bielsko-Aleksandrowice (summit of Carpathian Foothill). In the central part of southern Poland during the last 50 years (1966-2015) fog occurred on average during 53-67 days a year. The annual number of foggy days in Kraków (67 days) located in a structural basin was by 14-15 days higher than in Bielsko (53 days) situated in the Silesian Foothills. In the annual course, high fog occurrence (above 6 days per month) was observed from September to January, with the maximum in Kraków (10 days in October). At every station the monthly minimum of fog occurrence fell in July (2 days). In summer and spring the highest probability of fog occurrence was found on days with anticyclonic types and air advection from the northeastern (Na, NEa) and eastern (Ea, SEa) sectors. In autumn, a high probability was also found for the anticyclonic types with advection of air mass from the eastern and southern sectors. In the Carpathian Foothills (Bielsko) the probability of fog occurrence in winter was significantly enhanced only for the cyclonic types with air advection from the eastern sector (NEc, Ec, SEc) and nonadvective types Cc (cyclone centre) and Bc (cyclonic trough). Trends in the fog frequency were mostly insignificant. The only significant decreasing trend was found in Kraków on the annual scale and in summer when fog frequency was low.
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Cappadonia, Chiara, Pierluigi Confuorto, Diego Di Martire, et al. "Geomorphological Insights to Analyze the Kinematics of a DSGSD in Western Sicily (Southern Italy)." Remote Sensing 16, no. 21 (2024): 4040. http://dx.doi.org/10.3390/rs16214040.
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Deep-Seated Gravitational Slope Deformations (DSGSDs) are common in many geological environments, and due to their common limited displacement rate, they can remain unrecognized for a long time. Among the most significant events in Sicily is the Mt. San Calogero DSGSD. To contribute to a better understanding of its characteristics, including the geologic setting promoting its development, ongoing kinematics, and mechanism, a specific analysis was completed. In this paper, the results of this analysis, based on a three-folded strategy, are provided and interpreted in the context of DSGSD predisposing conditions and controlling factors. Especially, field observations associated to visual interpretation of aerial imagery were used for the identification and mapping of main geological features and landforms, high-resolution X-Band DInSAR data enabled researchers to fully characterize the deformational behavior of the slope, while a reduced complexity slope stability analysis allowed them to reconstruct the deep geometry of the DSGSD. Results from the analysis indicate that the DSGSD of Mt. San Calogero is composed of three blocks corresponding to fault-bounded tectonic elements and characterized by a specific kinematics and sensitivity to external forcing (i.e., rainfall), multiple landslides are associated to the DSGSD in the area and the deep geometry of the DSGSD is concave upward and resemble the characteristics of a rotational slide. The interpretation of the results suggests that the formation and the deformation of the Mt. San Calogero DSGSD are linked with the local and regional fault systems related to the Sicilian orogen, while shallow landslides are triggered, in clayey terrains, mostly by rainfalls. In addition, the integrated approach reveals that active tectonics and rainfalls in the San Calogero massive relief are the main driving forces of its different deformation behavior.
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Pantel, A., J. T. Romo, and Y. Bai. "Above-ground net primary production of plains rough fescue [Festuca hallii (Vasey) Piper] after a single defoliation on five landform elements." Canadian Journal of Plant Science 91, no. 4 (2011): 689–96. http://dx.doi.org/10.4141/cjps2010-030.
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Pantel, A., Romo, J. T. and Bai, Y. 2011. Above-ground net primary production of plains rough fescue [ Festuca hallii (Vasey) Piper] after a single defoliation on five landform elements. Can. J. Plant Sci. 91: 689–696. Above-ground net primary production (ANPP) was determined for plains rough fescue [Festuca hallii (Vasey) Piper] following a single defoliation to 7.5 cm stubble height on five landform elements in the Northern Mixed Prairie. The landform elements included north aspect-concave slopes, north aspect-convex slopes, south aspect-concave slopes, south aspect-convex slopes, and level uplands. Above-ground net primary production was determined for 2 yr after defoliating plants in May through November. Above-ground net primary production after defoliation was not dependent on landform elements in the first (P=0.23) and second years (P=0.22) after defoliation. In the first year after June through September defoliation, ANPP was reduced 29 to 41% (P <0.01), whereas May, October, or November defoliation had no significant effect on ANPP. Above-ground net primary production did not vary significantly (P=0.61) among months of defoliation in the second year after defoliation. Less ANPP in the first year after June through September defoliation indicates the need for ≥1 yr of deferred use to allow plants to regain their production potential. Unaffected ANPP after May, October, or November defoliation suggests plains rough fescue can be grazed annually. Recuperation of ANPP after defoliation depends on the month of the year in which plains rough fescue is defoliated, but not on landform elements in the Northern Mixed Prairie.
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Hoxha, Andri. "IMPACT OF TECTODYNAMIC AND MORPHODYNAMIC FACTORS ON THE SUSTAINABLE DEVELOPMENT OF THE SHPAT MOUNTAINOUS RIDGE." Knowledge International Journal 34, no. 3 (2019): 695–700. http://dx.doi.org/10.35120/kij3403695h.
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Shpat mountainous ridge represents a morphological unit with extremely prominent natural borders and rich natural resources. This abstract presents the natural potentials of Shpat mountainous ridge and a synthesized analysis of key aspects of tourism, mineral and water resources, forests and pastures management, etc. Shpat unit, is integral part of Bukanik ultrabasic massive, where are explorated cooper resources. The geological content of this mountain, contribues the mesozoic ultrabasic and flysch, calcareous rocks and quaternary deposition are also present. The morphologic and morphogenetic complex of the relief was created during the tectogenic period, especially during the tecto-orogenesis, where as consequence diverse magmatic, terrigenous and carbonates rocks were created. Structural relief landforms, are structural benches, flat surfaces formed in the aclinal structure, structural surfaces, denudational surfaces and concave fragment of front of the cuestas. The karstic surface forms were developed on limestones of different age and character. There is a conspicuously small number of dolines on the surface of the hardly dissolvable crystalline limestone, and the debris covering the surface is high enough for agriculture. The water infiltrating on the plateau surfaces in the karst springs. The knowledge of present morphodynamics implies features concerning the positive and restrictive role of each factor, which, by association, defines the potential of some gropus of processes and state of morphologic hazards in certain area. Such analyses multiplied in the last couple of years, when the occurrence of some mass wastings determined many geomorphologic risk situations allover Shpat mountainous ridge. The climate by regional and local differences of the weathering elements favorable to the development of morphological processes. In periglacial environments solifluction frequently occurs in association with permafrost or seasonally frozen ground, and under these circumstances it is more specifically described as gelifluction. Snow provides both and as ground insulation. The erosional potential of nivation is controlled primarily snow thickness or absence underlying permafrost. Cryoplanation terraces (also known as altiplanation terraces) are level or gently sloping surfaces found in the periglacial zone which are cut into bedrock on hill summits or upper peaks. The natural potentials of Shpat mountainous ridge have been analyzed as key elements of this area for sustainable development. The effects of the use of the natural resources and their influence on the economic structure have been analyzed defining the directions of the development on perspective of the rural area. The current developments at the agricultural rural area have produced changes to the physical-geographical elements, accelerating the pace of slope processes, where the predominant part of the settlements is established on the terrace levels, causing environmental degradation.
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Carvalho, Tarciane Clemente de, Eliane Maria Vieira, José Augusto Costa Gonçalves, and Gabriel Andrade Viterbo. "Análise das classes de vertentes e sua relação com o processo erosivo: Uma visão integrada da Bacia Hidrográfica do Rio Piracicaba-MG (Analysis of the classes of slopes and their relation with the erosive process in the Piracicaba-MG River Basin)." Revista Brasileira de Geografia Física 12, no. 4 (2019): 1619. http://dx.doi.org/10.26848/rbgf.v12.4.p1619-1634.
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O presente trabalho tem como objetivo apresentar uma análise das formas do terreno da bacia hidrográfica do rio Piracicaba, no estado de Minas Gerais, verificando as características morfológicas das curvaturas vertical e horizontal das vertentes, fruto das relações tectogenéticas e morfodinâmicas, que representam os fatores endógenos e exógenos. Fazendo uma avaliação das vertentes estabeleceu-se uma relação direta associada à fragilidade e suscetibilidade de perda de solo por arraste e carreamento de partículas, que causam assoreamento nos rios, além da associação do fluxo de escoamento superficial da água como sendo fator que acelera este processo. Foram empregados dados do Shuttle Radar Topography Mission (SRTM), utilizando o Sistema de Informações Geográficas (SIG) ArcGis 10.2.2, onde foram delimitadas as curvaturas vertical e horizontal do terreno. Os resultados atingidos foram os formatos do perfil das vertentes classificados como côncavo, retilíneo e convexo, e quanto a análise do direcionamento dos fluxos de escoamento da água foram classificados como convergente, planar e divergente e a suas sub-associações. A área de estudo apresenta seu maior território com curvatura Convergente, que corresponde à uma classe de vulnerabilidade forte, visto que esta tende a concentrar o fluxo de água favorecendo a erosão linear, seguida pela classe Divergente, que possui um enquadramento como baixa vulnerabilidade. A espacialização destas classes permitem a adoção de técnicas de manejo direcionadas para as áreas mais vulneráveis. A B S T R A C TThe present work aims to present an analysis of the landforms of the Piracicaba river basin in the state of Minas Gerais, verifying the morphological characteristics of the vertical and horizontal curvatures of the slopes, as a result of the tectogenetic and morphodynamic relationships that represent the endogenous factors and exogenous. An assessment of the slopes established a direct relationship associated with the fragility and susceptibility of soil loss by drag and particle haulage, which cause silting in the rivers, in addition to the association of the flow of surface water flow as a factor that accelerates this process. Data from the Shuttle Radar Topography Mission (SRTM) were used, using the ArcGis 10.2.2 Geographic Information System (GIS), where the vertical and horizontal curvatures of the terrain were delimited. The results obtained were the profile profiles of the slopes classified as concave, rectilinear and convex, and the analysis of the direction of flow flows were classified as convergent, planar and divergent and their sub-associations. The study area presents its largest territory with a convergent curvature, which corresponds to a strong vulnerability class, since it tends to concentrate water flow favoring linear erosion, followed by the Divergent class, which has a low vulnerability. The spatialization of these classes allows the adoption of management techniques directed to the most vulnerable areas. Keywords: profile of the slopes, vulnerability of terrain, thematic maps.
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Davydov, O. V., I. M. Kotovskyi, Yu Yu Onoyko, and S. V. Simchenko. "SURFACE MORPHOLOGY AND DYNAMICS COASTLINE OF THE DZHARYLHACH SPIT DISTAL END." Odesa National University Herald. Geography and Geology 27, no. 2(41) (2023): 11–27. http://dx.doi.org/10.18524/2303-9914.2022.2(41).268697.
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Introduction. Dzharylhach spit is the largest accumulative form within the Black Sea coast. Erosion processes have appeared along the front of the spit, which in certain local areas (“hot spots”) are quite dangerous and can cause the spit’s body breaks. Within Dzharylgach, “hot spots” are located in the proximal and distal parts. The Dzharylhach distal end is an important recreational facility that hosts tens of thousands of vacationers every year. The breach formation within the distal end will make its recreational use impossible, which in turn will lead to significant negative changes in the economic sector of the southern region of Ukraine. That is why the study of the morphological and morphodynamic conditions of the Dzharylhach distal end is relevant and has a very important economic emphasis. Research aim is to determine the modern morphological and morphodynamic conditions of the Dzharylgach spit distal part development, based on the materials of field and remote studies. Following research objectives would facilitate the achievement of this aim: a) to define the distal end concept and to describe the morphodynamic diversity of the accumulative forms’ corresponding component; b) to analyze the morphological conditions of the Dzharylhach spit distal end and to determine its constituent parts; c) to determine the quantitative parameters of the coast’s dynamics within the distal end based on the materials of field research, GPS‑fixation of coastal landforms and analysis of satellite images of different ages; d) to compare the results of remote sensing with the materials of the Global monitoring of beaches and determining the morphodynamic trends of the Dzharylhach spit distal end development. Research object is the Dzharylhach spit distal end. Research subject is the morphological and morphodynamic conditions of the Dzharylhach distal end development. Research methodology. A comprehensive approach was used to study the morphological and morphodynamic features of the Dzharylhach distal end, which was based on the analysis, comparison, and systematization of field geomorphological leveling materials, GPS‑fixation of the coastal landforms position, analysis of satellite images and Global remote monitoring of beaches. 27 ISSN 2303-9914 Вісник ОНУ. Сер.: Географічні та геологічні науки. 2022. Т. 27, вип. 2(41) Research results. The distal end of any free coastal accumulative form is its morphological component, which is as far as possible from the place where the form leaned against the bedrock coast. From the outside, the distal end has the appearance of a cape with an adjacent shoal, which protrudes towards the seawater area. In dynamic terms, the distal end is the most active component, which is an indicator of the modern conditions of the entire coastal form development. According to the features of coastal processes taking place within the distal end, they are divided into progradational, dynamic-stable and retrogradational. The Dzharylhach distal end represents the extreme eastern part of the spit, which has the shape of a hook on the outside and consists of coastal landforms of different genesis and age. An underwater shaft of small size is spread along the distal end front, which passes into a shoal, characterized by a significant drop in depth, which indicates the progradation of the spit’s body. According to the morphological structure, three components are distinguished within the distal end: a triangular base, an isthmus, and an expanded headland. Offshore bars of different ages are located within the triangular base. The ancient offshore bars are oriented from the southeast to the north-northwest, that is, they have a diametrically opposite direction with similar forms of the wide part of Dzharylhach. The distal isthmus and expanded headland are new Dzharylhach generations, which were formed over the last hundred years. The surface of the isthmus has a concave character, which is due to the presence of fans of overwashes and splashes. Arcshaped generations of modern offshore bars and swales, as well as lakes of lagoon origin represent the extended distal end. The quantitative parameters of the distal end dynamics presented in the work indicate the specific conditions of its development, under which the narrow part is actively eroded, and the expanded part increases and moves towards the sea. It should be noted that similar conditions also took place in the areas of the distal extremities of the Bakalska (the Black Sea) and Obytichna (the Sea of Azov) spits. Because of the narrowing, breaches were formed at the site of the isthmus, and the headlands turned into islands. Conclusions. Morphological features and morphodynamic trends of the distal end testify to the transformation of lithodynamic conditions within its limits. The presented studies allow us to state that the indicated distal end is not the discharge zone of a single alongshore flow of sediments directed from west to east. This is primarily evidenced by the morphology of the distal end underwater slope, within which there is only one local offshore bar, which is not connected with similar formations spread along the front of the spit. The Dzharylhach spit distal end development is due to the interaction of alongshore and transverse sediments transport, which are manifested against the background of human-complicated conditions of the coastal zone. In our opinion, there are two local lithodynamic cells within the distal: frontal and rear. The front one is characterized by the transport of debris material from the front of the isthmus to the loop-shaped spit, and the rear one is from the back side of the isthmus towards the leaned spit. According to the morphological structure, three components are distinguished in the distal part: a triangular base, an isthmus, and an expanded head. The presented materials allow us to assert that the development of the distal Dzharylgach Spit is caused by the interaction of alongshore and transverse transport of sediments, which are manifested against the background of human-complicated conditions of the coastal zone.
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Priyono, Kuswaji Dwi, and P. Priyono. "Analisis Morfometri dan Morfostruktur Lereng Kejadian Longsor di Kecamatan Banjarmangu Kabupaten Banjarnegara." Forum Geografi 22, no. 1 (2008): 72. http://dx.doi.org/10.23917/forgeo.v22i1.4926.
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The aims of this research are: (a) to study and classify the landslide hazard level, and (b) to analysis morphometry and morphostructure slope at occurrence slides in the research area. The sampling method applied in this research was stratified sampling, landform units were applied as strata. The sample within strata was determined according the landslide hazard based factor that caused landslides. Analysed of morphometry and morphostructure conducted in described of landform units. The landslide location was mapped by determining landslide point with Global Position System (GPS), and morphometry slope analysis in three images with Digital Elevation Model (DEM) analysis. The results showed that the degree of landslide hazard in the research area could be classified into 9 units landform with 5 landslide hazard level, from very low until very high. At very high landslide hazard existed occurrence landslides at most, whereas at very low landslide hazard existed occurrence at least. From slope morphometry aspect, the point of the most landslide case is in mountain midle slope (11), lower slope (9), and upper slope (5). Flows type, soil fall, and rockfall all happen in lower slope. Landslide types almost (80%) happen in lower slope, whereas slump type happen in upper, middle, and lower slope. From slope form aspect, 70% landslide cases happen in concave slope position and slope classes 3-5 (>9%). From morphostructure aspect, the research area hasn’t difference because of weathering level and litology structure condition which is relatively similar. Concave and aslant slope condition become the concentration point of surface flow water and under surface which are predicted be the most influence factor that cause landslide.
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VO, Hoang Cong, Hitoshi TANAKA, and Yuta MITOBE. "THEORETICAL STUDY ON THE RECOVERY PROCESS OF THE CONCAVE LANDFORM AFTER THE TSUNAMI." Journal of Japan Society of Civil Engineers, Ser. B1 (Hydraulic Engineering) 71, no. 4 (2015): I_31—I_36. http://dx.doi.org/10.2208/jscejhe.71.i_31.
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Fagundes, Gabriel Cunha Linhares, and Cláudia Maria Sabóia de Aquino. "IDENTIFICAÇÃO, CLASSIFICAÇÃO E ESPACIALIZAÇÃO DE DEPÓSITOS E FEIÇÕES TECNOGÊNICAS DE SUB-BACIAS URBANAS DO RIO POTI EM TERESINA/PI." REVISTA GEONORTE 12, no. 39 (2021): 108–30. http://dx.doi.org/10.21170/geonorte.2021.v.12.n.39.108.130.
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Este trabalho objetiva analisar como o tecnógeno se concebe na cidade de Teresina, bem como com quais impactos se relaciona. Os depósitos tecnogênicos identificados foram classificados como Úrbicos, Espólicos, Construídos, Gárbicos e Dragados estando ligados a impactos ambientais (alagamento, assoreamento de riachos e aterramento de lagoas), socioambientais (insalubridade, desabamentos) e urbanos (especulação imobiliária, ocupações). A pesquisa aponta que tais materiais necessitam de manejo adequado pelo poder público e população, de modo a melhorar a qualidade de vida nas áreas onde os mesmos foram identificados.
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Pennock, D. J. "Multi-site assessment of cultivation-induced soil change using revised landform segmentation procedures." Canadian Journal of Soil Science 83, no. 5 (2003): 565–80. http://dx.doi.org/10.4141/s03-010.
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The range of soil properties associated with soil taxonomic class results from natural soil formation and soil-changing effects of human activity. My goal was to assess cultivation effects on soil formation and soil organic carbon (SOC) at four cultivated and two native hummocky till sites from the same climatic region of Saskatchewan. A revised landform segmentation procedure was used for comparisons across sites. Neither A horizon thickness nor SOC was related to topographical attributes at the native sites, but both had significant relationships (P = 0.001) with profile curvature (Pearson r= −0.53 and −0.57 for A horizon thickness and SOC, respectively), specific dispersal area (r = −0.40 and −0.54) and plan curvature (r = −0.24 and −0.34) at the cultivated sites. The greatest decreases in A horizon thickness (16 cm) and SOC (56 Mg ha-1) at the cultivated sites occurred in divergent shoulder elements, which have high rates of tillage-induced soil loss. Increases in soil thickness (including depth to calcium carbonate) occurred in concave footslope and depressional elements, but in situ losses of SOC outweighed the effects of SOC deposition. Soil thinning caused increases in the proportion of Orthic Regosols and decreases in the proportion of Calcareous Chernozems, but horizonation changes in the dominant Orthic Chernozems were minor. The self-terminating nature of the horizonation changes and improved conservation measures suggest that the future rate of soil change in these landscapes may be lower than in the past. Key words: organic carbon, topography, landscape-scale, erosion, tillage redistribution, digital elevation model, cesium
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Wu, Jun Feng, Yun Sheng Wang, and Yong Hong Luo. "The Characteristics and Mechanism of Large Scale Landslides between Huangjinping and Detuo in Daduhe River." Advanced Materials Research 243-249 (May 2011): 3211–16. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.3211.
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Daduhe River is in western Sichuan Basin which is across the Songpan-Ganzi geosynclinal fold system and the Yangtze para-platform. There are some complex geological backgrounds in this region, such as active new tectonic movements, frequent earthquakes and high seismic intensity. Remote sensing interpretation shows that there are lots of large-scale landslides existing between Huangjinping and Detuo in the upper reaches of Daduhe River. It has been shown by the research that the reason why large-scale landslides happened frequently in this region has a close relationship with its special fault structure, landform and strata distribution. Landslides always develop along the concave bank, free face of mountain or the thin mountain ridge and they all have close connection with fault in different degrees. Although the lithology of this section is constituted by ancient Kangding complex, yet the adverse rock mass discontinuity and free face combination lay a foundation for slope’s deformation and progressive failure. The earthquake force, however, is the key factor triggering landslides.
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Webb, TH, and SJ Burgham. "Catenary relationships of downland soils derived from loess, South Canterbury, New Zealand." Soil Research 32, no. 1 (1994): 1. http://dx.doi.org/10.1071/sr9940001.
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Very limited information is available on soil variability within the large soil map units of the loess-mantled downlands of the east coast of South Island, New Zealand. In this study eight profiles were sampled in a catenary transect across a valley to assess the morphological, chemical and particle-size changes both within and between soil profiles for both sunny and shady aspects. Profiles from each landform element had similar sequences of horizons but thickness of horizons varied. Profiles on shoulder slopes had thinnest topsoil and subsoil horizons above underlying fragipans. There was a rapid thickening of topsoils and depth to fragipans immediately below the point of slope inflection between planar midslopes and concave lower slopes. The most striking difference in soil morphology was the overthickened topsoil horizons in footslope sites. This was attributed to effects of cultivation, either directly, through mechanical movement of soil material during cultivation operations, or indirectly, through the promotion of soil erosion. There was no indication of the expected catenary relationship involving translocation of exchangeable bases from upper to lower slopes. Differences in P-retention, KCl-extractable aluminium and clay content were identified in soils with different aspects but were not attributed to climatic differences.
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Gärtner-Roer, Isabelle, Nina Brunner, Reynald Delaloye, Wilfried Haeberli, Andreas Kääb, and Patrick Thee. "Glacier–permafrost relations in a high-mountain environment: 5 decades of kinematic monitoring at the Gruben site, Swiss Alps." Cryosphere 16, no. 5 (2022): 2083–101. http://dx.doi.org/10.5194/tc-16-2083-2022.
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Abstract. Digitized aerial images were used to monitor the evolution of perennially frozen debris and polythermal glacier ice at the intensely investigated Gruben site in the Swiss Alps over a period of about 50 years. The photogrammetric analysis allowed for a compilation of detailed spatio-temporal information on flow velocities and thickness changes. In addition, high-resolution GNSS (global navigation satellite system) and ground surface temperature measurements were included in the analysis to provide insight into short-term changes. Over time, extremely contrasting developments and landform responses are documented. Viscous flow within the warming and already near-temperate rock glacier permafrost continued at a constant average but seasonally variable speed of typically decimetres per year, with average surface lowering limited to centimetres to a few decimetres per year. This constant flow causes the continued advance of the characteristic convex, lava-stream-like rock glacier with its oversteepened fronts. Thawing rates of ice-rich perennially frozen ground to strong climate forcing are very low (centimetres per year) and the dynamic response strongly delayed (timescale of decades to centuries). The adjacent cold debris-covered glacier tongue remained an essentially concave landform with diffuse margins, predominantly chaotic surface structure, intermediate thickness losses (decimetres per year), and clear signs of down-wasting and decreasing flow velocity. The former contact zone between the cold glacier margin and the upper part of the rock glacier with disappearing remains of buried glacier ice embedded on top of frozen debris exhibits complex phenomena of thermokarst in massive ice and backflow towards the topographic depression produced by the retreating glacier tongue. As is typical for glaciers in the Alps, the largely debris-free glacier part shows a rapid response (timescale of years) to strong climatic forcing with spectacular retreat (>10 m a−1) and mass loss (up to >1 m w.e. specific mass loss per year). The system of periglacial lakes shows a correspondingly dynamic evolution and had to be controlled by engineering work for hazard protection.
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Anenkhonov, O. A., and B. B. Naidanov. "Syntaxonomy of steppe plant communities on the permafrost soils on the Vitimskoye Plateau (Transbaikalia region)." Vegetation of Russia, no. 48 (2024): 117–27. http://dx.doi.org/10.31111/vegrus/2024.48.117.
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There is a lot of studies concerning steppe vegetation in the Transbaikalia region, though detailed floristic classification has been developed recently (Korolyuk, 2017, 2019). However, some of the specific types of steppe communities are still out of that classification so far. In particular, meadow steppe communities on permafrost soils at the northern part of the forest-steppe subzone on the Vitimskoye Plateau (Transbaikalia) still are not classified. The paper aims to design the syntaxonomic position and brief characteristics of this particular vegetation. Rather similar communities are known as cryoxerophytic steppes from more northern regions (Yurtsev, 1978). Taking into account that studied area is slightly less cold we call Tranbaikalian meadow steppe communities on permafrost soils as hemicryomesoxerophytic steppe. Our studies have been carried out within the Eravninskaya depression (Fig. 1) in the southwest of the Vitimskoye Plateau (Transbaikalia). The depression of hollow-concave shape with flat relief extends for about 80 km to the northeast, while the width is about 63.5 km, and elevation is about 950 m a. s. l. The climate is sharply continental, with frosty snowless winters and short and warm summers. The permafrost is common throughout the depression. The mean annual precipitation is 250–400 mm, with 60 % of the total amount falls in July–August. The main types of soils are represented by permafrost chernozem and turf soil (Badmayev et al., 2006). Meadow steppe in combination with the Gmelin larch and white birch coppices form the forest-steppe landscape. Field studies have been conducted in 2009 and 2018, and 26 relevés (of 100 m2) of steppe communities were collected. The Braun-Blanquet approach for the classification of vegetation has been applied, and the nomenclature of syntaxa follows to ICPN (Theurillat et al., 2021). Steppe vegetation of the south-west of Vitimskoye Plateau belongs to the class of Cleistogenetea squarrosae Mirkin et al. ex Korotkov et al. 1991, order Helictotrichetalia schelliani Hilbig 2000, and alliance Helictotrichion schelliani Hilbig 2000. Habitats of hemicryomesoxerophytic steppe communities differ from those of suballiances described within the Helictotrichion schelliani in relation to position across landforms and the soil profile pattern. Differences are noticeable contrast to habitats of the Thymenion baicalensis Korolyuk 2017 communities, and are less pronounced compare to those of the Stipenion baicalensis Korolyuk 2017. The special peculiarity of the floristic composition of hemicryomesoxerophytic steppes is imparted by the presence of Kobresia filifolia, K. myosuroides and Thalictrum alpinum, indicating the cryophilic habitats. Moreover, there is a set of montane-steppe species also evidencing the same environment situation. Based on the floristic composition (Table) and ecological specificity we describe a new suballiance of steppe vegetation, containing 2 new associations. The suballiance Leontopodio conglobati–Caricenion pediformis Anenkhonov suball. nov. Nomenclatural type of the suballiance (holotypus) — ass. Kobresio filifoliae–Festucetum lenensis Anenkhonov et Naidanov. Diagnostic species (d. s.): Bistorta alopecuroides, Bupleurum sibiricum, Festuca lenensis, Gentiana decumbens, Leontopodium conglobatum, Lychnis sibirica, Rumex acetosa, Salix kochiana, Tephroseris integrifolia, Thalictrum alpinum. The suballiance represents hemicryomesoxerophytic steppe communities confined to the permafrost soils in the cold and sharply continental climate in the northern part of the forest-steppe subzone of the Transbaikalia region. The suballiance communities occupy flatland habitats and produce the forest-steppe landscape in combination with larch (Larix gmelinii) or birch (Betula platyphylla) coppices. Less often these communities are confined to the southern slopes when forest dominates in the landscape. The floristic composition of the hemicryomesoxerophytic steppes is significantly different from that of the cryophytic steppes described in other regions. Particularly, there are sufficient differences comparing to cryoxerophytic steppe of the Altai mountains, the subalpine montane steppe and kobrezian communities of Mongolia, and meadow-steppe communities in northern areas of Yakutia and West Chukotka. All of this support establishing the new syntaxon to integrate the hemicryomesoxerophytic steppe of Vitimskoye Plateau into the syntaxonomy of steppe vegetation. Defining the rank of the Transbaikalian hemicryomesoxerophytic steppes was based on the specificity of habitats, especially confinement to permafrost soils. Such criterion clearly separates these communities from steppes of the alliance Stipenion baicalensis, which are developed on seasonally frozen soils. The suballiance includes 2 associations: (1) Kobresio filifoliae–Festucetum lenensis — relatively more cryophytic; (2) Orostachyo malacophyllae–Festucetum lenensis — relatively more thermophytic. Ass. Kobresio filifoliae–Festucetum lenensis Anenkhonov et Naidanov ass. nov. (Table, rel. 1–15, Fig. 2). Nomenclatural type (holotypus hoc loco): Table, rel. 4 (field number nb18-23), Republic of Buryatia, Eravninskiy district, 43 km NE Sosnovo-Ozerskoye village, 52.82825° N, 111.93925° E, Varioherbosae-Sedge-Kobresia meadow steppe, 10.07.2018. Authors — B. B. Naidanov, O. A. Anenkhonov. D. s.: Artemisia rupestris, Equisetum arvense, Galatella dahurica, Heteropappus altaicus, Ixeridium gramineum, Kobresia filifolia, K. myosuroides, Potentilla anserina, P. arenosa. The association represents hemicryomesoxerophytic steppe communities on meadow-chernozem permafrost soils. The habitats are relatively more cryophytic (comparing to the 2nd association). Communities usually occupy open flatlands or slightly concaved surfaces of various configurations, and also cover shady (the most often northerly and easterly) sites close to coppices. Ass. Orostachyo malacophyllae–Festucetum lenensis Anenkhonov et Naidanov ass. nov. (Table, rel. 16–26; Fig. 3). Nomenclatural type (holotypus): Table 1, rel. 20 (field number nb18-22), Republic of Buryatia, Eravninskiy district, 36 km NE Sosnovo-Ozerskoye village, 3.3 km SSE Khorga settlement, 52.78897° N, 111.84138° E, Varioherbosae-Fesque-Pasqueflower meadow steppe, 10.07.2018. Authors — B. B. Naidanov, O. A. Anenkhonov. D. s.: Aconogonon angustifolium, Achillea asiatica, Campanula glomerata, Dianthus versicolor, Orostachys malacophylla, Schizonepeta multifida, Silene jeniseensis, Veronica incana. This association, like a previous one, represents hemicryomesoxerophytic steppe communities, however, it is relatively more thermo- and xerophytic. Communities occur on slightly elevated flat surfaces, hillocks, sites on well–warmed forest edges – most often from the southern and western sides of coppices, and on southern and south-western slopes of hills. To resume, hemicryomesoxerophytic steppe communities of Eravninskaya depression on the south-west of Vitimskoye Plateau represent a peculiar type of steppe vegetation, originated due to special habitats on the permafrost soils at the northern part of the main area of steppe vegetation in Transbaikalia region. These steppe communities belong to the new suballiance (with two new associations) of steppe vegetation.
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Frassi, Chiara, Alessia Amorfini, Antonio Bartelletti, and Giuseppe Ottria. "Popularizing Structural Geology: Exemplary Structural Geosites from the Apuan Alps UNESCO Global Geopark (Northern Apennines, Italy)." Land 11, no. 8 (2022): 1282. http://dx.doi.org/10.3390/land11081282.
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Popularizing endogenic geological processes that act deep on the Earth during geologic time producing orogenic belts requires a great effort. Consequently, geosites dealing with structural geology are surveyed with a lower frequency. Geological structures, however, may strongly control and model the territory and/or trigger the exogenous processes responsible for a specific landform/landscape. We describe here three geosites in the Apuan Alps UNESCO Global Geopark (Tuscany, Italy) to highlight their geoheritage values. We used the classical methods applied in structural geology to conceive and design three new interpretative panels of structural geosites using simple language and graphic schemes that facilitate the understanding of geological structures. The three selected structures were produced by different deformation regimes and at different structural depths. The first geosite is the boundary between the metamorphic and non-metamorphic rocks and represents the boundary of the Apuan Alps tectonic window. The second geosite is the spectacular Mt. Forato natural arch and the third represents a beautiful example of folds. Each panel is characterized by QR codes that allow the reader to access a short geological glossary, the Apuan Alps Geopark website, and a short evaluation survey on the quality of the interpretative panel.
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NASUTION, RATNA HUSIN, Triyatno ., and Endah Purwaningsih. "PEMETAAN TINGKAT BAHAYA LONGSOR DI JALAN LINTAS KECAMATAN LEMBAH GUMANTI - KECAMATAN PANTAI CERMIN KABUPATEN SOLOK." JURNAL BUANA 2, no. 5 (2018): 488. http://dx.doi.org/10.24036/student.v2i5.256.
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ABSTRAK
 Penelitian ini bertujuan untuk mengetahui kondisi karakteristik lahan dan tingkat bahaya longsor di daerah penelitian. Hasil penelitian sebagai berikut: 1. Karakteristik lahan: a) iklim: curah hujan 2.224 mm/tahun, b) geologi: struktur lapisan batuan dengan bentuk miring dan miring bergelombang, c) geomorfologi: bentuklahan pegunungan dan perbukitan, satuan bentuklahan lereng kaki gunung api, kemiringan lereng yang sangat curam 43% dan curam 40% dengan panjang lereng yang sedang 45 m, panjang 100 m, sangat panjang 210 m, bentuk lereng lurus, cembung, cekung, bervariasi cembung cekung, d) tanah: tekstur tanah lempung berpasir dan pasir berdebu, struktur tanah remah, gumpal, bukit tunggal, konsistensi tanah sangat gembur, lepas-lepas, permeabilitas tanah sangat cepat 21 cm/jam dan cepat 7,09 cm/jam e) hidrologi: kedalaman muka air tanah <500 cm f) penggunaan lahan: semak belukar/alang-alang, tegalan/kebun campuran dan pemukiman. 2. Tingkat bahaya longsor: a) sedang: Pada daerah Batang Hari, Aia Dingin, Cubadak, Lolo. b) Tinggi: Pada daerah Aia Ampu.
 
 Kata kunci : lahan, longsor.
 
 
 ABSTRACT
 This research of aims are determine the condition of land characteristics and the level of landslide hazard in the research area. The sample of this research is purposive sampling, the sample is taken in accordance with the research objectives. The research show as follows: 1. Land characteristics: a) climate: rainfall 2.224 mm / year, b) geology: rock layer structure with an oblique shape and tilted wavy, c) geomorphology: form of mountainous and hilly land, landform unit of the foot slope volcano, very steep slope of 43% and steep 40% with medium slope length 45 m, length 100 m, very long 210 m, and the shape of the slope is straight, convex, concave, irregular. d) soil: soil texture sandy loam, and dusty sand, structure of land crumb,lumpy, single hill, consistency of land very loose, loose , soil permeability very fast 21 cm/h and fast 7,09 cm/h e) hydrology: groundwater depth <500 cm f) land use: shrubs / reeds and moor / seasonal gardens and settlement 2. the level of landslide hazard: a) medium: At Batang Hari, Aia Dingin, Cubadak, Lolo. b) high: At Aia Ampu.
 
 Keyword: land, hazard.
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Capoane, Viviane, Danilo Rheinheimer Dos Santos, and Tatiana Mora Kuplich. "Efeito do Uso da Terra e Relevo na Distribuição Espacial e Vertical de Carbono do Solo em uma Bacia Hidrográfica Agrícola (Effect of land use and landform on soil spatial and vertical carbon distribution in an agricultural watershed)." Revista Brasileira de Geografia Física 9, no. 6 (2016): 1629. http://dx.doi.org/10.26848/rbgf.v9.6.p1629-1643.
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Neste trabalho foram investigadas as relações entre o uso da terra e relevo com os teores de carbono orgânico total (COT) do solo, a fim de entender os padrões de distribuição espacial e vertical de C em uma bacia hidrográfica agrícola da região central do estado do Rio Grande do Sul. Amostras de solo foram coletadas em 57 pontos, em cinco camadas: 0-5, 5-10, 10-20, 20-40, 40-60 cm, totalizando 285 amostras. A grade de amostragem foi distribuída em diferentes classes de uso da terra (mata, área úmida, lavoura, campo antrópico) e de declividades (0-3, 3-8, 8-20%). O teor do COT foi estimado pelo método de digestão úmida. Os resultados mostraram que as áreas antropizadas apresentaram os menores teores de COT dentre os usos avaliados. Nas lavouras os menores teores de COT foram encontrados na meia encosta com declive entre 8-20% e as maiores em vertentes côncavas convergentes na posição inferior da encosta, a média entre os pontos de amostragem na camada 0-5 cm foi de 15,10,58 g kg-1. As áreas de campo apresentaram os menores teores de COT dentre os usos avaliados (χ ̅ 122,61 g kg-1). Já os maiores teores foram obtidos em área úmida (χ ̅ 43,14,53g kg-1), comprovando o grande potencial desses locais no sequestro de carbono. Os resultados obtidos sugerem que os processos de erosão, redistribuição e deposição de COT são grandemente influenciados pelo uso da terra e pelas formas do relevo e, essas informações podem ser utilizadas para avaliar a dinâmica do carbono do solo na paisagem. A B S T R A C T In this work was investigate the relationship between land use and relief to the levels of total organic carbon (TOC) in order to understand its spatial and vertical distribution patterns in an agricultural watershed from the central region of Rio Grande do Sul State. Soil samples were collected at 57 points in five layers: 0-5, 5-10, 10-20, 20-40, 40-60 cm, totalizing 285 samples. A sampling grid was distributed in different land use classes (forest, wetland, tillage, field) and slope (0-3, 3-8, 8-20%). The TOC content was estimated by wet digestion method. The results indicated that the anthropic areas of watershed had the lowest TOC among all of evaluated land uses. On tillage smaller TOC were found in middle hillside slope between 8-20% and higher in converging concave sections at the bottom of the hillside position and the average of the sampling points in the layer 0-5 cm was 15.1±0.58 g kg-1. The areas of field had the lowest TOC among the evaluated uses ( 12±2.61 g kg-1). In contrary, the highest ( 43.1±4.53 g kg-1) TOC contents were recorded in wetland, demonstrating the great potential of these locations in carbon sequestration. The result suggests that erosion, redistribution and deposition of TOC are greatly influenced by land use and relief forms. These findings can be useful tool to evaluate the soil carbon dynamics in the landscape. Keywords: Water erosion, Agriculture, Distribution, Deposition.
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Khan, A. A., and A. C. Chaterjee. "GEOMORPHOLOGY, TERRACES OF VARIOUS DOMINE OF ALAKNANDA ITS TRIBUTARIES AND NEOTECTONISAM, GARHWAL HIMALAYA PARTS OF CHAMOLI TEHRI UTTAKASHI & PAURI UTTAR PRADESH (UTTRARKHAND) INDIA." International Journal of Advanced Research 11, no. 05 (2023): 523–62. http://dx.doi.org/10.21474/ijar01/16908.
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The Geological and Geomorphological study in Upper Ganga basin has been attempted in parts of de Uttarkashi,Chamoli, Pauri and Tehri districts, an area of 10000 Sq.kms in parts of QA sheet 53J and 53 N on 1:50000 scale of Garhwal Himalaya U.P has been covered presently known as Uttrakhand State of Union of India. Out of total area of study, an area about 3500 sq.Kms (1:50000 scale) has been selected for detailed Geological, Geomorphological and Sedimentological study. The area of Upper Ganga basin consisting of Alaknanda, Bhagirathi, Bhilangna, Nandakini, Mandakini, Pindar, Dhauli- Ganga Bal- Ganga, Madhmeshwar Ganga and Berhi Ganga. The Alaknanda is chracterised by six terraces followed by Bhagirathi with five terraces, Bhilangna Nandakini four terraces, Mandakini /Pindar/Dhauli-Ganga /Balganga three terraces, Madhmshwar Ganga two terraces and Berhi Ganga one terrace, amidst these Alaknanda is trunk stream and others are tributaries. Geomorphologically, the area is divided in to seven geomorphic units viz High relief formerly glaciated area, Structural hills, Denudational hills, Area of mass wasting, High level dissected fans River Terraces and Present day flood plain of Alaknanda and its tributaries. These units area developed in response to lithology to erosional land depositional activities and tectonic in which they are embedded. Each unit is characterized by distinct drainage, diagnostic geomorphic landform elements and features, photo charcters and morphogenetic expression. The other geomorphic features and elements identified in the area are point bar, channel bar, alluvial fans ,talus cone , rock cut terraces fan cut terraces , abandoned and fossil channel courses,epigenetic gorges, strant lines landslides, rock fall scree and scree slope, retreating scarp, abandoned cirque, cirque morines, arêtes, threshold, horn peak and glacial lake. The area genetically comprised of terraces of three domains, viz. glacial, fluvio-glacia and fluvial which represent distinct environment of sedimentation of Pleistocene, late Pleistocene and Holocene time during Quaternary period. The glacial terraces are identified at an average elevation of 1150 m above m.s.l. the fluvio-glacial terraces at an average elevation of 975 m above m.s.l. and fluvial terraces at an average elevation between 650 to 900 m above m.s.l. The Badrinath temple is situated in glaciated trough valley of Alaknanda, which comprise of, four levels of the glacial terraces (lateral moraine), cirque moraine on mountain flanks and the terminal moraine at the base of valley. whereas Kedarnath in the upstream of Mandakini, where number of well developed cirques were identified on high mountain, they are mostly arm chair shaped hollows with a steep to vertical head walls, concave floor and a threshold, these cirques are noticed at an average height of about 4500 m. The Kedarnath temple is situated in glaciated trough valley on quaternary platform formed by coalescing of cirque, lateral moraine and terminal moraine. The-Himalayan thrust like Central thrust Srinagar thrust, Alaknanda fault, Tons thrust show flattening dip suggesting that they lie at comparatively at shallow depth at short distance, down dip from their out crops, recent movements along the trace of these thrust/ faults are not of high and longer magnitude but have considerably affected Quaternary terraces of glacial, fluvio-glacial and fluvial domain of Alaknanda and its tributaries. Beside drainage, river bed profile, landscape architect and over all morphogenetic expression of the area, this bears the adverse impact of tectonic activity. The imprints of neotectonisam associated in the area indicate that these thrust /faults are active and have, signatures of sinking of landscape, mass wasting activities and posed neosiemic hazards and tectano-ecological problems, bears signatures of sinking of the area, mass wasting activities and neosiemic hazards. The geomophological study of the area, overall morphogenetic illustration, imprints of neotectonisam, disposition of terrces of different domains, mass wasting activities, drainage net, channel morphology, landform elements of glacial, fluvioglacial and fluvial domain of Alaknanda and its tributaries indicate that tectonically the area is active and slow movements are taking plae along thrust, faults and lineament. In the area North of Wazri in Jamuna valley, North of Uttarkashi around Sainj in Bhagirathi valley, around Tugnath and Chamoli and South of Joshimuth in Alaknanda valley revealed that there is sharp persistent curvilinear break in topography, which has geothermal manifestation at Wazri Gagnani anda Tugnath in the form of emitation of hot springs. This curvilinear line has further reconfigurated the neo stream net works system and affected morphogenetic expression it appears to be due to horizontal movement of sub - tectonic plate towards south, which, is sole collective and cumulative causative factor in dislocation of tectonic ecology of the area and has resulted micro earthquake shocksand and segmental sinkiking of area. The overall study revealed that the the area is sensitive active and is vulnerable to any techtono- seismic event it is matter of serious concerned and needs further attention.
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Korolyuk, A. Yu. "Syntaxonomy of steppe vegetation of the Republic of Buryatia." Vegetation of Russia, no. 31 (2017): 3–32. http://dx.doi.org/10.31111/vegrus/2017.31.3.
Full textAbstract:
Transbaikalia is the vast region in Southern Siberia withnumerous mountain ridges within the upper basins of the three big rivers, the Amur (Pacific Ocean basin), the Yenisei and the Lena (Arctic Ocean basin). The most part of Transbaikalia territory is covered by woodlands, however, the steppes are an inherent component in the southern part of the region. Steppe communities occur throughout the broad range of habitats varying in humidity, edaphic conditions, and anthropogenic disturbance. The main aims of presented study are: (1) to develop a phytosociological classification of transbaikalian steppes and to characterize the syntaxa distinguished, (2) to reveal principal ecological factors that have an influence on regional syntaxonomical patterns of the steppe vegetation. From 2005 to 2013, the field studies were carried out in the territory of the Republic of Buryatia. During this period we collected the data set of 829 steppe relevйs. Supplementary characteristics were followed by every relevй: geographical coordinates (measured by GPS); altitude; inclination and exposition; rock outcrops, large stone and debris cover; sand content in the soil. For each relevй climatic parameters from the WorldClim web-database were determined. Plant species indicator values for southern Siberia have been applied (Korolyuk, 2006); the average indicator value for moisture at every relevй was calculated. The data set was stored and managed in the IBIS 6.2 software. To analyze the data structure, a canonical correspondence analysis (CCA) was used. As a result 11 associations were distinguished, all of them belong to the class Cleistogenetea squarrosae Mirkin et al. ex Korotkov et al. 1991. The class represents main dry grassland diversity of the East Siberian–Central Asian sector of Palaearctic (Korolyuk, 2002). The continuous range coincides with the steppe and forest-steppe zones and mountain belts, encompassing Southern Siberia in Russia, as well as the significant part of People’s Republic of Mongolia and Inner Mongolia province in China. Under conditions of the ultracontinental climate, the steppe communities penetrate far to the North in North-Eastern Asia. This class consists of two orders: Stipetalia krylovii (typical bunchgrass steppes of the steppe zone and mountain steppe belt) and Helictotrichetalia sсhelliani (meadow steppes and rich-in-species bunchgrass steppes of mountain forest-steppe). The order Stipetalia krylovii Kononov, Gogoleva et Mironova 1985 represents the central order of the class. It comprises typical steppes predominated by bunch grasses as usual. The order is diagnosed by the same species like those of the class. N. Ermakov (2012) attempted to narrow this order. In his understanding (see below underlined), the order combines typical steppes of Yakutia and is characterized by following features. Communities are extremely poor — 4–9 species per 100 м2. I think that this statement is incorrect. In original publication (Mirkin et al., 1985), wh ere the new association Stipetum krylovii has been described, authors plotted the releve at the size of 1 м2 only. Therefore I can assume that species richness of these steppe communities has been wrongly estimated in regard of 100 м2 plots. According to my own data from the Lena River valley in vicinities of the city of Yakutsk the richness of 20 species (in average) per 100 м2 plot is typical for xerophytic steppes. Yakutian steppes of Stipetalia krylovii are differentiated by meadow steppe species (mesoxerophytes): Artemisia commutata, Festuca lenensis, Poa transbaicalica with a high constancy and many species with a low constancy. From my data, in Transbaikalia such species as Artemisia commutata and Festuca lenensis are common in petrophytic steppes both typical and meadow. In Yakutia, Poa botryoides is typical (d. s. Stipetalia krylovii) instead of Poa transbaicalica. Participation of numerous mesoxerophytes with the low constancy is common for typical steppes from different regions of Southern Siberia and Mongolia (Hilbig, 1995; Namzalov, 2015; Makunina, 2016). Yakutian steppes of Stipetalia krylovii are differentiated by halotolerant plants, namely Saussurea amara and Puccinellia tenuiflora. According to results of my studies as well as literature data, presence of the both species is characteristic for steppe communities in the alases only. Alases are formed as shallow depressions among the taiga landscapes in Central Yakutia, maded by thermokarst, and covered by the meadow or steppe vegetation (Troeva et al., 2010). In such landscapes steppes are spatially patterned into combination with halophytic communities. In well-drained landscapes halotolerant plants are absent. In the definition of Stipetalia krylovii N. Ermakov (2012) based on publications devoted to alases, when steppes from drained terrains were omitted. Thus, none of the three criteria suggested by N. Ermakov (2012) and mentioned above is not acceptable for distinguishing typical steppes of Yakutia from analogue communities of Southern Siberia, including Transbaikalia. This means that the attempt to validate the order Cleistogenetalia squarrosae Mirkin et al. ex Ermakov 2012 was superfluous (Art. 29c, ICPN). Consequently, this order is a synonym of Stipetalia krylovii. Also, the alliance Poo attenuatae–Cleistogenion squarrosae Mirkin et al. ex Ermakov 2012 is to be recognized as a synonym of the alliance Stipion krylovii. The alliance Stipion krylovii Kononov, Gogoleva et Mironova 1985 is the central alliance of the order Stipetalia krylovii. It includes non-petrophytic steppes which are common mainly in the mountain steppe belt and the steppe zone. In Western Transbaikalia the alliance is represented by two associations: Cymbario dahuricae–Stipetum krylovii Hilbig (1987) 1990 (the central association of the alliance) and Cleistogeno squarrosae–Festucetum dahuricae Dulepova et Korolyuk 2015 (sandy steppes). Alliance Thymion gobici Mirkin et al. ex Hilbig 2000 comprises xerophytic petrophyte steppes of Transbaikalia, Central and Eastern Mongolia, the Inner Mongola province (China). In Buryatia it is represented by three associations. Ass. Eremogone capillaris–Festucetum lenensis Mirkin et al. 1988 — the central association of the alliance. Petrophytic communities are common both on convex windswept slopes and ridge tops in the forest-steppe and steppe belts. Physiognomy of communities is determined by small cushion-forming species and dwarf semishrubs. Communities of the ass. Selaginelletum rupestris–sanguinolentae ass. nov. are often confined to ridge-top parts of north-facing slopes with outcrops or screes in the Selenga river basin. Community physiognomy is determined by predomination of the low-growing trailing perennial Selaginella sanguinolenta which makes communities noticeably darker as compared to the surrounding steppes. Ass. Selaginello rupestris–Artemisietum subviscosae ass. nov. — the endemic association found in the Barguzin depression. The communities occur on fine gravel soils on river terraces, deluvial foreslopes and convex slopes in the mountain lower belt. Order Helictotrichetalia schelliani Hilbig 2000 comprises meso-xerophytic grasslands, mainly meadow steppes of East Siberian–Central Asian sector of Palaearctic. It unites the most widespread non-forest plant communities of forest-steppe landscapes. The area of the order extends considerably to the north in comparison with the order Stipetalia krylovii. In Transbaikalia, the meso-xerophytic grasslands predominate in the mountain forest-steppe belt up to the heights of 900–1000 m a. s. l. Alliance Helictotrichion schelliani Hilbig 2000 — the central alliance distributed in Altai-Sayan mountains, Western Transbaikalia, northern mountains of Central and Western Mongolia. In the study area we distinguished two suballiances. Suballiance Stipenion baicalensis suball. nov. — the central suballiance representing meadow steppes on fine soils. Communities are found at gentle straight slopes, sometimes occupying slightly concave sites of mountain ridge slopes. The suballiance consists of three associations. The central association is Veronico incanae–Stipetum baicalensis Peterson ex Hilbig 2000. It occurs in the steppe and forest-steppe belts, occupying gentle slopes and piedmont foreslopes. Ass. Carici pediformis–Spiraeetum aquilegifoliae ass. nov. represents meadow steppes with well developed shrub layer. The communities usually occupy steep south-exposed slopes with large stones or outcrops, often of concave shape. By their physiognomy and species composition, the described communities look like the association Amygdalo pedunculatae–Spiraeetum aquilegifoliae, which substituted by them in more humid forest-steppe landscapes. Ass. Thalictro foetidi–Koelerietum cristatae ass. nov. unites the more moist type of the suballiance. The communities are found in the forest-steppe landscapes, usually along gentle straight or concave slopes. Often they occupy steeper parts of slopes along the edges of larch and birch forests. Suballiance Thymenion baicalensis represents petrophyte meadow steppes of Western Transbaikalia. The communities are common in the forest-steppe and steppe landscapes on stony, often convex slopes, ridge tops, sometimes on screes. Ass. Potentillo acaulis–Thymetum baicalensis Chytry et al. 1993 — one of the most widespread steppe plant communities. Ass. Selaginello rupestris–Artemisietum monostachyae ass. nov. comprises rich meadow petrophytic steppes. The communities are found in forest-steppe landscapes in the Uda and the Barguzin rivers basins. Ass. Sedo aizoi–Festucetum lenensis ass. nov. includes the more moist variants of meadow petrophytic steppes. The communities are rich and polydominant, mainly with predomination of mesoxerophytic meadow steppe species. They are confined to stony slopes and ridge tops, usually at the forest margins in the Selenga river basin. Strong ecological gradients have been revealed by the numerical analysis of associations. The first axis of CCA-ordination is correlated with humidity which is determined by precipitation, and the soil moisture that depends on landform features as well. The second axis represents edaphic conditions — stones and sand content in the soil. The third axis is the most likely of complex character, however it is especially related with temperature and solar radiation. Due to interlacement of various environmental gradients a high variability of habitats and consequent complicated vegetation patterns within the studied region occured. Further development of the dry grassland syntaxonomy of Inner Asia could be advanced by the involvement of the data from the territories of Eastern Transbaikalia, People’s Republic of Mongolia (Outer Mongolia) and the province of Inner Mongolia in China. This will allow to delineate the distribution of syntaxa, as well as to make a general revision of the class Cleistogenetea squarrosae all over its area of distribution.
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Li, Qihang, Yunmin Wang, Jiawen Wang, Bin Gong, and Xiaoshuang Li. "Numerical Simulation of Overburden Deformation Mechanism and Surface Settlement Characteristics Induced by Underground Coal Mining: A Case Study." Geological Journal, January 22, 2025. https://doi.org/10.1002/gj.5149.
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ABSTRACTUnderground mining in mountainous regions presents a significant geological hazard, characterised by the occurrence of land subsidence and movement of overlying strata. To aggrandise the theory of mine rock mechanics, we conducted a systematic investigation into the deformation and failure mechanisms of overlying strata as well as the patterns of surface subsidence in mountainous regions. With the method of engineering mechanics and theoretical analysis, supplemented by the universal distinct element code (UDEC) numerical simulation, the mining status of Songzao mine was simulated effectively. Herein, the results revealed that the nonlinearity of the overlying strata failure field occurred during mining, as evidenced by an increase in the failure field when the coal approached the seam roof. The subsidence curve of the underlying lower strata exhibits an inverted trapezoid pattern, while that of the overlying upper overburden displays a funnel‐shaped trend. Additionally, the upward transmission displacement velocity was significantly attenuated due to the shielding effect exerted by the key stratum in the overburden, resulting in a greater spatial separation from the underlying strata. The critical stratum fractures as the working face advanced to 120 m, subsequently leading to an increase in vertical displacement and cessation of surface subsidence. The surface subsidence value and speed, however, exhibited a gradual increase as the coal seam mining progressed. Due to the influence of mountain surface landforms, the subsidence value of convex landforms surpasses that of concave landforms, thereby expediting the rate of subsidence and resulting in geological hazards.
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Lenart, Jan. "Vliv historické těžby železných rud v Podbeskydské pahorkatině a Moravskoslezských Beskydech na současný reliéf." Geologické výzkumy na Moravě a ve Slezsku 24, no. 1-2 (2017). http://dx.doi.org/10.5817/gvms2017-1-2-21.
Full textAbstract:
Although relatively extensive extraction of the pelocarbonate iron ore in the Podbeskydská pahorkatina Upland and the Moravskoslezské Beskydy Mts. have terminated until the end of the 19th century, the remnants are rarely preserved in the recent relief as collapsed shafts, mining pits, dumps or their combinations. The adits are occurring infrequently, because the majority of them are completely collapsed or at least the entrance is filled up with rocks. Similarly, the shafts formerly many meters deep, are recently reflected only as shallow concave hollows. Distinct post-mining landforms are still preserved e.g. in Chlebovice, Libotín near Štramberk, Čeladná or Kozlovice villages. The causes of wrong preservation of these forms, which stood at the beginning of the Ostrava industrial agglomeration, are as: (i) mining in the incoherent fine flysch rocks, (ii) primitive mining methods without wooden setts, and (iii) intensive anthropogenic activities after the mining termination in the landscape. Some of the localities with preserved free underground spaces are remnants after the mining of the other or the related materials, or even crevice type caves. Because of the historical importance of the iron ore mining in the wider area, I would recommend consideration of at least some basic protection of preserved landforms. Otherwise, at the present rate of the landscape changes intensity, they would shortly vanish.
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Paškauskas, Stasys, and Irena Vekeriotienė. "Hypsometric assessment of the pre-last Glaciation (Late Saalian) topography, the south-east Lithuania." Baltica, 2013, 105–14. http://dx.doi.org/10.5200/baltica.2013.26.11.
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The article deals with the hypsometric assessment of the pre-last Glaciation (Late Saalian) topography which represents a glaciogenic landforms of the Medininkai stadial in south-east Lithuania. The study area belongs to two elevations as orographic units: the Lyda Plateau and the Ašmena Upland. Cartometric topography analysis has been performed in nine reference areas based on large-scale (1:25 000) cartographic maps. The topographic relative height varies from 11.8 m to 30.6 m and depends on the surface altitude (correlation coefficient R = 0.85). The correlation links between the base and top surfaces (R = 0.74–0.92), concave-convex graph of hypsometric curves and value of hypsographic integrals (0.45–0.58) indicate that in general pre-last Glaciation topography of south-east Lithuania at the present stays in equilibrium conditions.
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Hoxha, Andri. "THE ROLE OF THE GEOLOGICAL COMPOSITION IN THE STRUCTURAL MORPHOLOGY OF THE TERRITORY OF ALBANIA." KNOWLEDGE - International Journal, March 20, 2019, 613–18. http://dx.doi.org/10.35120/kij3003613h.
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In the context of geological composition, the territory of Albania closely depends on the geographic position. The presence of our country in the alpine-Mediterranean fold belt and the geological structures, called Albanide, have determined the intense development of the internal tectonic processes, as well as the external processes. The tectonic regime of the geological structures during the Miocene epoch to the Quaternary period, was accompanied by reverse faults and thrust faults one over the other of the tectonic areas of Albania. The morphologic and morphogenetic complex of the relief was created during the tectogenic period, especially during the tecto-orogenesis, where as consequence diverse magmatic. terrigenous and carbonates rocks were created. The highly pronounced character of the differential tectonic movements during morphotectonic evolution, especially during the plio-quaternary period, has created the actual morphological features of the relief of Albania.In the context of geological composition, the territory of Albania closely depends on the geographic position. The presence of our country in the alpine-Mediterranean fold belt and the geological structures, called Albanide, have determined the intense development of the internal tectonic processes, as well as the external processes. The tectonic regime of the geological structures during the Miocene epoch to the Quaternary period, was accompanied by reverse faults and thrust faults one over the other of the tectonic areas of Albania. The morphologic and morphogenetic complex of the relief was created during the tectogenic period, especially during the tecto-orogenesis, where as consequence diverse magmatic. terrigenous and carbonates rocks were created. The highly pronounced character of the differential tectonic movements during morphotectonic evolution, especially during the plio-quaternary period, has created the actual morphological features of the relief of Albania.The migration of orogenesis from east to west is conditioned by the dominance of mountainous ranges and ridges in the eastern and central parts, as well as in the fields and lowlands of the western part of Albania. The relief is distinguished by its diversified morphogenetic traits, due to the highly complex morphotectonic evolution, a large number of carbonate, terrigenous and magmatic rocks, as well as the significant influence of the outward processes. Due to the existence of composition of the large number of tectonic faults as well as the high values of tectonic uplift and downlift, the genetic composition of the structural relief was also created. Each of the sub-types within the structural relief is closely related to the presence of complex geological structures such as anticlinal, synclinal, monoclinal and aclinal structures. An important role have the structural landforms formed in the structures of faulting type, thus in the horst and graben structures, which are associated with very large morphological contrasts of the relief.A part of the horst and graben structures during the last period of pliocene and during the quaternary was involved by intense tectonic lifting movements, resulting to a fragmentation of flat bottom of ex-former depressions, and consequently they were transformed into depressions with fragmented bottom. A large part of structural relief landforms, such as structural benches, flat surfaces formed in the aclinal structure, structural surfaces, denudational surfaces and concave fragment of front of the cuestas, have been used for the construction of rural and urban settlements, for the road infrastructure network, the construction of human buildings, as well farmlands for the country's economy. The detailed analysis of the structural relief features, based on the characteristics of geological construction, enables prospects for taking measures against geomorphological, seismic and hydrological hazards.
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A., A. Khan, and Chaterjee A.C. "GEOMORPHOLOGY, TERRACES OF VARIOUS DOMINE OF ALAKNANDA ITS TRIBUTARIES AND NEOTECTONISAM, GARHWAL HIMALAYA PARTS OF CHAMOLI TEHRI UTTAKASHI & PAURI UTTAR PRADESH (UTTRARKHAND) INDIA." May 17, 2023. https://doi.org/10.5281/zenodo.8001454.
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The Geological and Geomorphological study in Upper Ganga basin has been attempted in parts of de Uttarkashi,Chamoli, Pauri and Tehri districts, an area of 10000 Sq.kms in parts of QA sheet 53J and 53 N on 1:50000 scale of Garhwal Himalaya U.P has been covered presently known as Uttrakhand State of Union of India. Out of total area of study, an area about 3500 sq.Kms (1:50000 scale) has been selected for detailed Geological, Geomorphological and Sedimentological study. The area of Upper Ganga basin consisting of Alaknanda, Bhagirathi, Bhilangna, Nandakini, Mandakini, Pindar, Dhauli- Ganga Bal- Ganga, Madhmeshwar Ganga and Berhi Ganga. The Alaknanda is chracterised by six terraces followed by Bhagirathi with five terraces, Bhilangna Nandakini four terraces, Mandakini /Pindar/Dhauli-Ganga /Balganga three terraces, Madhmshwar Ganga two terraces and Berhi Ganga one terrace, amidst these Alaknanda is trunk stream and others are tributaries. Geomorphologically, the area is divided in to seven geomorphic units viz High relief formerly glaciated area, Structural hills, Denudational hills, Area of mass wasting, High level dissected fans River Terraces and Present day flood plain of Alaknanda and its tributaries. These units area developed in response to lithology to erosional land depositional activities and tectonic in which they are embedded. Each unit is characterized by distinct drainage, diagnostic geomorphic landform elements and features, photo charcters and morphogenetic expression. The other geomorphic features and elements identified in the area are point bar, channel bar, alluvial fans ,talus cone , rock cut terraces fan cut terraces , abandoned and fossil channel courses,epigenetic gorges, strant lines landslides, rock fall scree and scree slope, retreating scarp, abandoned cirque, cirque morines, arêtes, threshold, horn peak and glacial lake. The area genetically comprised of terraces of three domains, viz. glacial, fluvio-glacia and fluvial which represent distinct environment of sedimentation of Pleistocene, late Pleistocene and Holocene time during Quaternary period. The glacial terraces are identified at an average elevation of 1150 m above m.s.l. the fluvio-glacial terraces at an average elevation of 975 m above m.s.l. and fluvial terraces at an average elevation between 650 to 900 m above m.s.l. The Badrinath temple is situated in glaciated trough valley of Alaknanda, which comprise of, four levels of the glacial terraces (lateral moraine), cirque moraine on mountain flanks and the terminal moraine at the base of valley. whereas Kedarnath in the upstream of Mandakini, where number of well developed cirques were identified on high mountain, they are mostly arm chair shaped hollows with a steep to vertical head walls, concave floor and a threshold, these cirques are noticed at an average height of about 4500 m. The Kedarnath temple is situated in glaciated trough valley on quaternary platform formed by coalescing of cirque, lateral moraine and terminal moraine. The-Himalayan thrust like Central thrust Srinagar thrust, Alaknanda fault, Tons thrust show flattening dip suggesting that they lie at comparatively at shallow depth at short distance, down dip from their out crops, recent movements along the trace of these thrust/ faults are not of high and longer magnitude but have considerably affected Quaternary terraces of glacial, fluvio-glacial and fluvial domain of Alaknanda and its tributaries. Beside drainage, river bed profile, landscape architect and over all morphogenetic expression of the area, this bears the adverse impact of tectonic activity. The imprints of neotectonisam associated in the area indicate that these thrust /faults are active and have, signatures of sinking of landscape, mass wasting activities and posed neosiemic hazards and tectano-ecological problems, bears signatures of sinking of the area, mass wasting activities and neosiemic hazards. The geomophological study of the area, overall morphogenetic illustration, imprints of neotectonisam, disposition of terrces of different domains, mass wasting activities, drainage net, channel morphology, landform elements of glacial, fluvioglacial and fluvial domain of Alaknanda and its tributaries indicate that tectonically the area is active and slow movements are taking plae along thrust, faults and lineament. In the area North of Wazri in Jamuna valley, North of Uttarkashi around Sainj in Bhagirathi valley, around Tugnath and Chamoli and South of Joshimuth in Alaknanda valley revealed that there is sharp persistent curvilinear break in topography, which has geothermal manifestation at Wazri Gagnani anda Tugnath in the form of emitation of hot springs. This curvilinear line has further reconfigurated the neo stream net works system and affected morphogenetic expression it appears to be due to horizontal movement of sub - tectonic plate towards south, which, is sole collective and cumulative causative factor in dislocation of tectonic ecology of the area and has resulted micro earthquake shocksand and segmental sinkiking of area. The overall study revealed that the the area is sensitive active and is vulnerable to any techtono- seismic event it is matter of serious concerned and needs further attention.