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1
Huang, Shu You, Zhi Gang Yin, Jin Guang Zhang, Yu Shan Ren, and Jing Hai Zhou. "Research the Problem about the Silted Deposition of the Broken Model." Applied Mechanics and Materials 204-208 (October 2012): 279–83. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.279.
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On the foundation of the item that the residence flood controlled technique and standard tested and the analysis according to the formation of the sediment and the regulation of the sedimentation in the actual river. In the process of the studied item, design a kind of a new sedimentation basin in order to lower the sand carrying capacity of the down water in the limited distance and the biggest limit. Through the model experiment of this kind of the sedimentation basin and find out the result of the sink the sand under the different discharge, in order to guide the actual engineering application.
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Stollhofen, Harald. "Karoo synrift-deposition and its tectonic control at the evolving continental margin of Namibia." Zeitschrift der Deutschen Geologischen Gesellschaft 149, no. 4 (March 19, 1999): 519–632. http://dx.doi.org/10.1127/zdgg/149/1999/519.
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Stovin, Virginia R., and Adrian J. Saul. "Sedimentation in Storage Tank Structures." Water Science and Technology 29, no. 1-2 (January 1, 1994): 363–72. http://dx.doi.org/10.2166/wst.1994.0684.
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Although storage tanks provide an effective means of reducing the magnitude and frequency of combined sewer overflow discharges, and thereby of alleviating urban watercourse pollution, poorly designed storage structures frequently suffer from maintenance problems arising from sedimentation. The development of design guidelines that optimise the self-cleansing operation of storage structures is clearly a priority for urban drainage research. This paper describes a system that has been developed to study sediment deposition in laboratory model-scale storage structures. The patterns of deposition resulting from a selection of flow regimes are described, and the need for time-varying and time series storm tests is highlighted. Sedimentation patterns are shown to predominantly depend on the flow field, and the critical bed shear stresses for deposition and erosion in the model situation are identified. Hence, the potential application of numerical models to the design problem is discussed.
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Srivastava, Pradeep, George A. Brook, Eugene Marais, P. Morthekai, and Ashok K. Singhvi. "Depositional environment and OSL chronology of the Homeb silt deposits, Kuiseb River, Namibia." Quaternary Research 65, no. 3 (May 2006): 478–91. http://dx.doi.org/10.1016/j.yqres.2006.01.010.
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AbstractPrevious studies suggest that the Homeb silts of the Kuiseb valley, Namibia (i) accumulated in a dune-dammed lake, (ii) are end-point deposits, (iii) represent an aggrading river bed, and (iv) are slackwater deposits. Thus, they have been used alternatively as evidence of past drier conditions or past wetter conditions. Lithostratigraphic analysis of two sediment sequences at Homeb indicates sedimentation by aggradation of the Kuiseb River triggered by a transition from an arid to humid climate. OSL ages for the sequences were obtained by the SAR protocol on aliquots of 9.6-mm and 4.0-mm diameter and on single grains. Four-millimeter aliquot minimum ages closely approximate the single-grain minimum ages and are younger than 9.6-mm aliquot minimum and central ages. Based on these results, the small-aliquot (4-mm) approach appears to provide ages comparable to those obtained by the more laborious and time-consuming single-grain method. Minimum ages indicate rapid deposition of the Homeb Silts in at least two episodes centered at ∼15 ka and ∼6 ka during climate transitions from arid to humid. Flash floods eroded the valley fills during slightly more arid conditions.
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Darquenne, C., K. L. Zeman, R. C. Sá, T. K. Cooper, J. M. Fine, W. D. Bennett, and G. K. Prisk. "Removal of sedimentation decreases relative deposition of coarse particles in the lung periphery." Journal of Applied Physiology 115, no. 4 (August 15, 2013): 546–55. http://dx.doi.org/10.1152/japplphysiol.01520.2012.
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Lung deposition of >0.5-μm particles is strongly influenced by gravitational sedimentation, with deposition being reduced in microgravity (μG) compared with normal gravity (1G). Gravity not only affects total deposition, but may also alter regional deposition. Using gamma scintigraphy, we measured the distribution of regional deposition and retention of radiolabeled particles (99mTc-labeled sulfur colloid, 5-μm diameter) in five healthy volunteers. Particles were inhaled in a controlled fashion (0.5 l/s, 15 breaths/min) during multiple periods of μG aboard the National Aeronautics and Space Administration Microgravity Research Aircraft and in 1G. In both cases, deposition scans were obtained immediately postinhalation and at 1 h 30 min, 4 h, and 22 h postinhalation. Regional deposition was characterized by the central-to-peripheral ratio and by the skew of the distribution of deposited particles on scans acquired directly postinhalation. Relative distribution of deposition between the airways and the alveolar region was derived from data acquired at the various time points. Compared with inhalation in 1G, subjects show an increase in central-to-peripheral ratio ( P = 0.043), skew ( P = 0.043), and tracheobronchial deposition ( P < 0.001) when particles were inhaled in μG. The absence of gravity caused fewer particles to deposit in the lung periphery than in the central region where deposition occurred mainly in the airways in μG. Furthermore, the increased skew observed in μG likely illustrates the presence of localized areas of deposition, i.e., “hot spots”, resulting from inertial impaction. In conclusion, gravity has a significant effect on deposition patterns of coarse particles, with most of deposition occurring in the alveolar region in 1G but in the large airways in μG.
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Isdarmanto, Isdarmanto, and Oentoeng Soebyanto. "ANALISIS POTENSI PANTAI GLAGAH SEBAGAI EKOWISATA UNGGULAN DI KABUPATEN KULONPROGO." Kepariwisataan: Jurnal Ilmiah 12, no. 02 (May 31, 2018): 1–12. http://dx.doi.org/10.47256/kepariwisataan.v12i02.82.
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Glagah Beach is one of the most potential beaches and has the uniqueness as the charm and excellence of other southern seas. Glagah Beach located in Kulon Progo Regency is the only beach in Java that has a breakwater and has a lagoon on the edge of the sea separated by the sea so that large waves do not reach the lagoon. According to the typology of Glagah beach it self can be included in the classification of marine deposition coast. This is because the beach is formed due to the deposition deposition of river sedimentation material to the sea. This condition can be indicated by the emergence of a barrier coast emerging due to sedimentation from the river that empties into the location, then subject to marine effects that result in the formation of the lagoon. The process of sedimentation that occurs due to the flow and sedimentation of the river mouth that causes sedimentation in the coastal area. Qualitative research methods used with data collection techniques in the form of observation, interviews, documents, and various sources of data so it can be more clearly known geographical aspects of Glagah Beach, tourism profile, tourist visit conditions, tourism potential Glagah Beach, and to know the constraints which faced Glagah Beach tourism object and how the development strategy of Glagah Beach tourist attraction area in the future. Glagah Beach is a natural attraction that has the privilege and excellence compared to other beaches in Yogyakarta that need to keep the sustainability and need to be managed more effectively by the community and the local government as a policy holder so Glagah Beach became one of the leading ecotourism object which is interesting in Kulon Progo Regency Yogyakarta.
Keywords: Glagah Beach; Sea Lagoon; Barrier Coast
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de Sousa, Lateiro Salvador, Raphael Muli Wambua, James Messo Raude, and Benedict Mwavu Mutua. "Assessment of Water Flow and Sedimentation Processes in Irrigation Schemes for Decision-Support Tool Development: A Case Review for the Chókwè Irrigation Scheme, Mozambique." AgriEngineering 1, no. 1 (March 6, 2019): 100–118. http://dx.doi.org/10.3390/agriengineering1010008.
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Water flow and sedimentation processes have been significantly erratic at the Chókwè Irrigation Scheme (CIS) and have affected its hydraulic performance. Given its expansion there is need to understand these processes taking place on-site and along the channels of the scheme. CIS being the biggest project of its kind in Mozambique requires proper management of water flow and sedimentation processes. Therefore, the effect of water flow, sediment transport and deposition parameters on the performance of the CIS is needed. In order to determine the effect of spatial and temporal water flow and sediment distribution trends along the irrigation canals, there is need to establish a correlation between these parameters. Determining the influence of water flow velocity on sediment settling rate at different depths along the canal reaches is important in managing the CIS. In addition, a developed decision-support tool to predict sediment deposition is required. For this reason, it is therefore crucial to carry out a timely assessment of water flow and sedimentation processes in CIS in a review concept. From the current review, some gaps that exist for more focused research on Chókwè Irrigation Scheme have been identified. In this regard therefore, there is need to develop an effective support tool for managing water flow and sediment deposition along the canal reaches with a view to increasing crop production in CIS.
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A. AL-Mafraji, Ekram, and Haider A. Al-Mussawy. "ENVIRONMENTAL AND HYDRAULIC MONITORING USING CATIONIC DYES TO INVESTIGATE THE BARRIERS EFFECT ON KAOLIN DEPOSITION." Journal of Engineering and Sustainable Development 25, no. 5 (September 1, 2021): 103–12. http://dx.doi.org/10.31272/jeasd.25.5.11.
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Dyes are used in hydraulic fields such as hydraulic tracking to show the flow path, monitor flow lines within a ground dam, or track the spread of contaminated water within horizontal pipes and environmental fields as environmental indicators in titrations, such as titration of precipitate composition. Some environmental experiments dispense with the dye's use because it interferes with other compounds, such as interfering with the turbidity readings even if non-reactive dyes, but the present study transformed this problem into a positive phenomenon to benefits from the dye in both fields. The research methodology includes a laboratory analysis using different parameters such as discharge of suspension, the volume of dye, and the percentage of initial water depth at maximum water depth also theoretical analysis of the previous research methodology. The experimental results show that cationic dyes' absorption (methylene blue dye, MB and crystal violet, CV) is directly proportional to the percentage of kaolin deposition in the sedimentation tank areas. Finally, MB and CV dyes are used in both fields in one trial(such as tracking flow movement, monitoring the vortices formed using baffles, and inter between the amount of kaolin precipitated in each zone the sedimentation). However, MB is the best compare to CV.
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Ehrbar, Daniel, Lukas Schmocker, Michael Doering, Marco Cortesi, Gérald Bourban, Robert Boes, and David Vetsch. "Continuous Seasonal and Large-Scale Periglacial Reservoir Sedimentation." Sustainability 10, no. 9 (September 12, 2018): 3265. http://dx.doi.org/10.3390/su10093265.
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Sustainable reservoir use is globally threatened by sedimentation. It has been generally recognized that inadequate consideration of reservoir sedimentation has caused the worldwide decline of net storage. Numerical models are useful tools to simulate sedimentation processes and can be used to derive efficient counter-measures and sediment management strategies. They can be applied to both existing and potential future reservoirs to predict long-term sedimentation. In this study, an application of a simple, robust, and stable numerical 1D model to Gebidem reservoir in Switzerland accompanied by field measurements is presented. It focusses on seasonal and large-scale reservoir sedimentation processes that occur continuously throughout the whole deposition season, while episodic events like turbidity currents are not taken into account. The model simulates both the delta formation of coarse sediments and the lake-wide sedimentation from homopycnal flows. The model is used to assess the effects and significance of varying boundary conditions like inflow, suspended sediment concentration, particle size distribution (PSD), or reservoir operation. It will be demonstrated that future reservoir operation and PSD are as important as future runoff evolution. Based on these findings, implications on future reservoir operation, also considering climate change, are discussed. Finally, an outlook on pending research topics is given.
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Erawan, Muhammad Trial Fiar, Tri Prartono, and Ali Arman. "Characteristics of Sediments Deposition in Karimata Strait." ILMU KELAUTAN: Indonesian Journal of Marine Sciences 23, no. 2 (June 21, 2018): 93. http://dx.doi.org/10.14710/ik.ijms.23.2.93-98.
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Karimata strait connects South China Sea and Indonesia territorial seas where the strait current pattern is affected by west and east monsoon. This condition influences particles depositing sedimentation process in the strait. Lack information about sediment depositing rate at the straits dozens years ago makes this research is important to be conducted. This research was to estimate sediment depositing rate in the strait in two areas, near shore and off shore of Borneo. The research was conducted on June to September 2015 used coring sediment samples. Those samples were derived from Baruna Jaya VIII Ship Cruise on June 2015 that was collaborative research between Ministry of Marine and Fisheries Affairs of Indonesia and National Nuclear Center of Indonesia (BATAN).Samples were analyzed in the laboratory of Chemical and Ocean, Department of Environmental and Natural Resources, Center of Radiation and Isotope, National Nuclear Center of Indonesia (BATAN). Estimation of sediment depositing rate used natural isotope 210Pb. The study shows that the depositing rate of the nearest to Borneo area is about 0.92 kg.m-2.y-1 (1965) and increases to be 3.31 kg.m-2.y-1 (2009). The other area is about 0.08 kg.m-2.y-1 (1840) and increases to be 1.78 kg.m-2.y-1 (2010). This result implies that the sediment depositing rate at the nearest area to Borneo is higher than the off shore. Keywords: Near shore, off shore, Natural Isotop 210Pb, CRS (Constant Rate of Supply) model
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Ashley, R. M., D. J. J. Wotherspoon, M. J. Goodison, I. McGregor, and B. P. Coghlan. "The Deposition and Erosion of Sediments in Sewers." Water Science and Technology 26, no. 5-6 (September 1, 1992): 1283–93. http://dx.doi.org/10.2166/wst.1992.0571.
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The problems caused by sediments in sewers are now universally acknowledged. A number of countries have set up comprehensive programmes to study all aspects of sewer sediments; their occurrence, nature and movement. In the UK the Water Research centre and others have funded a comprehensive study of the sediments in the Dundee sewer system. The rate of sedimentation and the yield strength of the sediments have been investigated and considered in terms of the subsequent erosion by increasing flows. The sediments have been found to be cohesive in nature and highly resistant to erosion in the main interceptor sewer, whereas in the trunk sewers the sediments are more granular and less cohesive in nature. A sewer classification system is suggested which is based on physical characteristics, and also relates to the nature of the sediments deposited, and the bed-load material conveyed close to the bed.
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Maiden, Kenneth J., and Gregor Borg. "The Kalahari Copperbelt in Central Namibia: Controls on Copper Mineralization." SEG Discovery, no. 87 (October 1, 2011): 1–19. http://dx.doi.org/10.5382/segnews.2011-87.fea.
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ABSTRACT The Kalahari Copperbelt stretches discontinuously for 800 km from central Namibia to northern Botswana (Figure 1; Borg, 1988; Borg and Maiden, 1989). In central Namibia, copper mineralization, hosted by slate and phyllite, is intermittently developed over more than 60 km of strike of the Kagas Member of the Klein Aub Formation. The strata-bound nature of copper occurrences led early explorers to the conclusion that copper was either syngenetic, i.e., emplaced during deposition of the host strata, or diagenetic, i.e., emplaced into the host strata during burial and compaction. As a result, initial exploration largely focused on “favorable” stratigraphic units as target horizons and for the most part ignored structurally controlled target areas of significant economic potential. Subsequent research at the (presently inactive) Klein Aub Mine and elsewhere in the Namibian part of the belt showed that, although copper concentrations are broadly strata-bound, the structural associations (e.g., the relation to a late reverse fault at Klein Aub) and detailed textural features (e.g., copper in veins, brittle fractures, cleavage-parallel lenticles, and tectonic breccia zones) indicate that copper mineralization was emplaced into structurally controlled sites late in the deformation history of the region. The conclusion of the present review is that economically viable copper accumulations resulted predominantly from one or more regionally extensive but locally structurally controlled hydrothermal events, mostly subsequent to formation of the dominant cleavage. As a result, modern exploration should focus primarily on favorable structures, particularly potential dilatant sites in tectonically complex zones.
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Gurmu, Zerihun Anbesa, Henk Ritzema, Charlotte de Fraiture, Michel Riksen, and Mekonen Ayana. "Sediment Influx and Its Drivers in Farmers’ Managed Irrigation Schemes in Ethiopia." Water 13, no. 13 (June 24, 2021): 1747. http://dx.doi.org/10.3390/w13131747.
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Excessive soil erosion hampers the functioning of many irrigation schemes throughout sub-Saharan Africa, increasing management difficulties and operation and maintenance costs. River water is often considered the main source of sedimentation, while overland sediment inflow is overlooked. From 2016 to 2018, participatory research was conducted to assess sediment influx in two irrigation schemes in Ethiopia. Sediment influx was simulated using the revised universal soil loss equation (RUSLE) and compared to the amount of sediment removed during desilting campaigns. The sediment deposition rate was 308 m3/km and 1087 m3/km, respectively, for the Arata-Chufa and Ketar schemes. Spatial soil losses amounts to up to 18 t/ha/yr for the Arata-Chufa scheme and 41 t/ha/yr for the Ketar scheme. Overland sediment inflow contribution was significantly high in the Ketar scheme accounting for 77% of the deposited sediment, while only 4% of the sedimentation at the Arata-Chufa scheme came from overland flow. Feeder canal length and the absence of canal banks increased the sedimentation rate, however, this was overlooked by the stakeholders. We conclude that overland sediment inflow is an often neglected component of canal sedimentation, and this is a major cause of excessive sedimentation and management problems in numerous irrigation schemes in sub-Saharan Africa.
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Olshtynska, O. P., G. M. Ivanova, and I. I. Pustovoit. "BIOGENIC SILICA SEDIMENTATION ON THE SHELF AND CONTINENTAL SLOPE OF THE BLACK SEA." Geological Journal, no. 2 (July 15, 2021): 79–89. http://dx.doi.org/10.30836/igs.1025-6814.2021.2.226856.
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Investigation of the marine sediments processes, regularities of their accumulation in the inland seas is one of the main tasks of marine geology and sedimentology. Biogenic sedimentation is extremely important in the general sediment deposition cycle in the Black Sea basin. This article provides an overview of the literature and analysis of our own research of the distribution of biogenic siliceous deposits in Holocene bottom sediments on the shelf and continental slope of the Black Sea. The composition and conditions of biosilicates formation, their relationship with coccolithic silts and sapropels in sedimentary strata, sources and forms of siliceous biogenic matter input, the dynamics of transformation of modern bottom sediments, as well as the influence of various environmental factors on the process of sedimentary accumulation of silica in the Black Sea basin in the late quarter are considered. The relevance of the topic is caused by insufficient coverage of a number of issues regarding the sources of mobilization and the nature of material input, the features of the origin and deposition of silicate biogenic matter in the basin, paleogeoecological factors that influenced on sedimentogenesis in the late Quarter. The study of the formation processes of modern bottom sediments in a wide range of facies conditions is of undoubted practical importance for diverse geological, sedimentological and facies research, both fundamental and applied, related to prospecting, exploration and exploitation of minerals, as well as for using the results obtained in the development of marine water area.
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Stovin, Virginia R., and Adrian J. Saul. "Efficiency prediction for storage chambers using computational fluid dynamics." Water Science and Technology 33, no. 9 (April 1, 1996): 163–70. http://dx.doi.org/10.2166/wst.1996.0202.
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Research was undertaken in order to identify possible methodologies for the prediction of sedimentation in storage chambers based on computational fluid dynamics (CFD). The Fluent CFD software was used to establish a numerical model of the flow field, on which further analysis was undertaken. Sedimentation was estimated from the simulated flow fields by two different methods. The first approach used the simulation to predict the bed shear stress distribution, with deposition being assumed for areas where the bed shear stress fell below a critical value (τcd). The value of τcd had previously been determined in the laboratory. Efficiency was then calculated as a function of the proportion of the chamber bed for which deposition had been predicted. The second method used the particle tracking facility in Fluent and efficiency was calculated from the proportion of particles that remained within the chamber. The results from the two techniques for efficiency are compared to data collected in a laboratory chamber. Three further simulations were then undertaken in order to investigate the influence of length to breadth ratio on chamber performance. The methodology presented here could be applied to complex geometries and full scale installations.
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Wulandari, Dyah Ari, Desyta Ulfiana, and Priyo Nugroho Parmantoro. "Analysis of Application of Sediment Trap in Rivers as An Effort Reservoir Sedimentation Control." MEDIA KOMUNIKASI TEKNIK SIPIL 26, no. 2 (February 2, 2021): 229–36. http://dx.doi.org/10.14710/mkts.v26i2.28691.
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Reservoir sedimentation can be overcome by reducing the amount of sediment that enters the reservoir, by building check dam. The check dam has more deposited coarse sediment load than fine sediment load. Fine sediment that escapes the check dam will flow further and eventually enter the reservoir pond. Therefore it is necessary to build a building that can capture fine sediments. Construction is planned as a system of sediment trap in irrigation channels. The purpose of this study is to analyze the possibility of applying the sediment trap in the river to deposit sediments that escape the check dam. The analysis begins with the selection of the location of the sediment trap, then calculate the dimensions of the sediment trap and the amount of sediment that has settled. Based on the analysis of the selected dimensions with several combinations of gradation of sediment grains, sediment deposition that occurs ranges from 42 - 68%. So it can be concluded making the sediment trap in the river can be done. However, for the application of these sediment traps further research is needed regarding the dimensions of sediment traps that are most optimal for sediment deposition.
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Jiang, Hao, Jian Liang Rui, Hai Lin Li, De Hua Zhao, Jing Jing Fu, and Shu Qing An. "Research on Algal Bloom Control for Environment Engineering." Applied Mechanics and Materials 340 (July 2013): 971–74. http://dx.doi.org/10.4028/www.scientific.net/amm.340.971.
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Aquatic plants inhibit algae through nutrient competition, sludge sedimentation and the release of allelochemicals in three ways. Investigating Pistia stratiotes L in East Lake, Shao (2001) observed removal rate of the BOD5 achieved more than 70%; the total nitrogen removal efficiency was 60%, the total phosphorus removal efficiency was approximately 70% or more, and this biochemical inhibitory effect may promote algal settlement. Ho Pool (1999) found that the Rhizoma AcoriGraminei could cause a water total nitrogen (TN) removal rate of 87.4%, a total phosphorus (TP) removal rate of 43.9%, and a dissolved oxygen (DO) increase of 26.6%. These studies suggest that through the promotion of the lake TN and TP, aquatic plants influence bio-deposition into sediments, in addition to their role in the nutrient cycling of lakes. Furthermore, many studies have shown that aquatic macrophytes can produce allelochemicals that could inhibit the growth of algae (Donk & Bund, 2002; A. Gross & Boyd, 1998; Elisabeth M. Gross, 2003; E. M. Gross & Sütfeld, 1994; Mulderij, Smolders, & Van Donk, 2006; Mulderij, Van Nes, & Van Donk, 2007).
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Shahidi, Sheila, Azadeh Jafari, Sanaz Dalal Sharifi, and Mahmood Ghoranneviss. "Deposition of Nano Tungsten Oxide on Glass Mat Using Hot Filament Chemical Vapor Deposition for High Catalytic Activity." High Temperature Materials and Processes 35, no. 5 (May 1, 2016): 515–21. http://dx.doi.org/10.1515/htmp-2015-0051.
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AbstractDifferent properties of nanostructured materials such as physical, chemical and catalytic properties based on metal nanoparticles for various applications have been studied extensively on account of their attraction these days. Nanocrystalline tungsten oxide (WO2) can chemically break down adsorbed organic contaminants in sunlight. In this research work, a novel photocatalyst of WO2/glass mat nanocomposite has been prepared by hot filament chemical vapor deposition (HFCVD) method, which is used for the degradation of dyestuff from dyes wastewater. Morphology of treated mat was observed using a scanning electron microscope (SEM). The amounts of tungsten oxide on glass mat were examined using the energy dispersive X-ray (EDX) method. Electrical surface resistivity was also measured. It is concluded that oxidant sedimentation has been done physically without any structural changes and increasing of reaction time led to an increase in deposition of tungsten oxide and finally led to a decrease in the electrical resistance of glass mat. The photocatalytic activities of tungsten-oxide-deposited glass mat were assessed by analyzing the decrease in concentration of the methylene blue (MB) as a colorant after exposure to ultraviolet (UV) irradiation. The MB concentration decreases continuously, concomitant with the UV irradiation time up to 240 min. The results show that the WO2/glass mat nanocomposite exhibits high photocatalytic activity and provides a good way in the degradation field of dyes wastewater.
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Barrera Crespo, Pedro D., Erik Mosselman, Alessio Giardino, Anke Becker, Willem Ottevanger, Mohamed Nabi, and Mijail Arias-Hidalgo. "Sediment budget analysis of the Guayas River using a process-based model." Hydrology and Earth System Sciences 23, no. 6 (June 28, 2019): 2763–78. http://dx.doi.org/10.5194/hess-23-2763-2019.
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Abstract. The equatorial Daule and Babahoyo rivers meet and combine into the tidal Guayas River, which flows into the largest estuary on the Pacific coast of South America. The city of Guayaquil, located along the Guayas, is the main port of Ecuador but, at the same time, the planet's fourth most vulnerable city to future flooding due to climate change. Sedimentation, which has increased in recent years, is seen as one of the factors contributing to the risk of flooding. The cause of this sedimentation is the subject of the current research. We used the process-based Delft3D FM model to assess the dominant processes in the river and the effects that past interventions along the river and its estuary have had on the overall sediment budget. Additionally, a simulation including sea level rise was used in order to understand the possible future impact of climate change on the sediment budget. Results indicate an increase in tidal asymmetry due to land reclamation and a decrease in episodic flushing by river floods due to upstream dam construction. These processes have induced an increased import of marine sediment potentially responsible for the observed sedimentation. This is in contrast with the local perception of the problem, which ascribes sedimentation to deforestation in the upper catchment. Only the deposition of silt and clay in connected stagnant water bodies could perhaps be ascribed to upstream deforestation.
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Estigoni, Marcus Vinicius, Renato Billia Miranda, and Frederico Fabio Mauad. "Hydropower reservoir sediment and water quality assessment." Management of Environmental Quality: An International Journal 28, no. 1 (January 9, 2017): 43–56. http://dx.doi.org/10.1108/meq-07-2015-0153.
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Purpose Finer sediment particles (silt and clay) transported by rivers carry the major part of nutrient loads by absorption; thus, sediment settling can remove nutrients from the water column. The purpose of this paper is to analyze the relation between reservoir sedimentation and water quality by assessing the reservoir sedimentation process and the sediments’ characteristics. Design/methodology/approach Bathymetric surveys from 2004 to 2014 were analyzed to assess the sedimentation process. Core samples provided information on a layer-by-layer basis of the sediment deposits, and water samples near the surface and near the bottom provided information on sediment concentration, and adsorbed and dissolved nutrients. Findings The upstream region of a reservoir is already silted. From 2004 to 2014, the delta evoluted approximately 500 m downstream and the deposits were mainly composed of clay. An area of approximately 1,000 m between the delta and the dam should still be able to continue allowing sediment deposition in the coming years. Most of the nutrients were absorbed into the sediment particles, except for the nitrogen measured in the dry season. Research limitations/implications Although analyses of the full cycle of the nutrients were not carried out, the constant sediment trapping of finer sediments and the high rate of absorbed nutrients in the suspended sediment support the hypothesis that the reservoir has removed nutrients from aqueous media by adsorption into sediments. Practical implications In the studied case, reservoir sedimentation has led to better water quality downstream. Originality/value It is shown in this study that reservoir sedimentation may have positive effects on river water quality.
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Khakzad, Hamid. "OWA operators with different Orness levels for sediment management alternative selection problem." Water Supply 20, no. 1 (October 18, 2019): 173–85. http://dx.doi.org/10.2166/ws.2019.149.
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Abstract The importance of reservoir sedimentation management as a multi criteria problem in practice with multiple decision makers is evident when one considers that the cost of replacing storage lost annually due to sediment deposition throughout the world is in the order of US$13 billion. If sedimentation can be managed successfully, as it has been in some reservoirs, the loss in reservoir storage space due to this phenomenon can be lowered significantly. The purpose of this research is to develop the ordered weighted averaging (OWA) algorithm and apply it and to select the most preferred alternative with different Orness levels for sediment management in dam reservoirs to satisfy the technical and executive requirements, economic factors, social welfare, and environmental impacts. In this way, we present analytic forms of OWA operator weighting functions, each of which has properties of rank-based weights and a constant level of Orness, irrespective of the number of objectives considered. The model are successfully applied to the Dez hydropower reservoir, which has faced serious sedimentation problems. Results of this study provide a general class of parameterized aggregation operators that include the min, max, and average and have shown themselves to be useful for modeling many different kinds of aggregation problems.
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Dyuryagina, Antonina, and Aida Lutsenko. "Development of sedimentation resistant water-acrylic titanium dioxide dispersions." Eastern-European Journal of Enterprise Technologies 4, no. 6(112) (August 31, 2021): 51–59. http://dx.doi.org/10.15587/1729-4061.2021.239208.
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According to the results of the research, the effect of stabilization of dispersions of titanium dioxide in water-acrylic compositions was established. It was proved that in aqueous-acrylic suspensions at all variations of film-forming agent (from 0 to 5 g/dm3), the maximum of stabilizing activity of the surfactants under study is achieved at CSAS=0.25 g/dm3. The minimum deposition rate of titanium dioxide dispersions at a dosing of 0.25 g/dm3 of sodium polyacrylate was at the level of 0.097 10-3 g/s at any content of film-forming agent (Cff=0.5÷5 g/dm3) in suspensions. At the introduction of the same concentration (CSAS=0.25 g/dm3) of the polyether siloxane copolymer, a decrease in sedimentation rate to 0.053 10-3 g/s in suspensions with a limited acryl content (C≤1 g/dm3) was recorded. At an increase in the concentration of a film-forming agent (C>1 g/dm3) in suspensions, sedimentation stability decreased, which is proved by an increase in the sedimentation rate of TiO2 to 0.110∙10-3 g/s at Cff=5.0 g/dm3. It was found that in aqueous-acrylic suspensions with the film-forming content from 0.5 to 1 g/dm3, the minimum average diameter was 2.64÷3.1 μm CSAS=0.25 g/dm3. Further concentration of acryl (Cff=4÷5 g/dm3) at the same dosage of polyether siloxane copolymer was accompanied by an increase in the average particle size up to 4.30÷4.61 μm. The maximum of wedging activity of sodium polyacrylate (CSAS=0.25 g/dm3) corresponds to the same minimum of the average diameter (2–3 μm).
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Shotbolt, L. A., A. D. Thomas, and S. M. Hutchinson. "The use of reservoir sediments as environmental archives of catchment inputs and atmospheric pollution." Progress in Physical Geography: Earth and Environment 29, no. 3 (September 2005): 337–61. http://dx.doi.org/10.1191/0309133305pp452ra.
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Lakes and reservoirs act as sinks for both catchment and atmospherically derived particulates and so their sediments can provide valuable information on temporal changes in these inputs. While the use of lake sediments as environmental archives is well established, reservoir sediments have less frequently been used as temporal records. Yet, for investigating pollution histories, reservoirs are ostensibly of greater interest: they are generally located close to urban and industrial sources of pollution and accumulate sediment rapidly and over similar time periods to major emissions of pollutants. The lack of interest in reservoir sediments stems from the perception that fluctuating water levels are likely to result in significant sediment disturbance. This perception is sustained, perhaps mistakenly, by a lack of research into reservoir sedimentary systems. There is, therefore, a need to review the available published research on reservoir sedimentation processes and patterns, the relatively few studies that have used reservoir sediments and relevant studies from the lake-sediment literature, and thus critically evaluate the potential and problems of using reservoir sediments as temporal records of pollution. Current understanding of the processes of sedimentation and resulting distributions are reviewed. Some significant differences between sedimentation in lakes and reservoirs are highlighted and the implications for sampling and interpretation of sedimentary records discussed. It is suggested that, at present, a valuable resource is being underutilized and it is demonstrated that, where sediment deposition patterns are taken into account, reservoir sedimentary records can provide important data for reconstructing past atmospheric and catchment pollutant inputs.
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Zhang, Yunlong, Zhidong Bao, Luxing Dou, Li Jiang, Mingyang Wei, and Li Zhang. "Hydrodynamics and deposition in lacustrine shallow-water delta front: A combination of numerical simulations and modern sedimentation measurements." Interpretation 8, no. 3 (August 1, 2020): SM39—SM52. http://dx.doi.org/10.1190/int-2019-0176.1.
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With the exploration of tight oil and gas, shallow-water deltaic reservoirs have been attracting more and more attention. The sedimentary architecture of a shallow-water delta shows distinctive differences with that of a deep-slope delta. These differences may be associated with the mechanism and characteristics of the deposition in the area where the sediments unloaded. Based on modern sedimentary research of the Poyang Lake in China, this paper focuses on the processes of river flow entering a lake with a low dip angle. We conducted six sets of numerical simulations with different initial sedimentary flow velocities using Fluent software for analyzing the hydrodynamics and the sediment transportation in the shallow-water delta. We combined the simulation results with an analysis of the geomorphology of the Gangjiang Delta to reveal the deposition along the shoreline of the lacustrine shallow-water delta. The numerical simulation shows that the shallow-water delta is dominated by bed friction with an extensive hydrodynamical boundary layer. The bed shear stress, which varies with the changes in river flux, dominated the sediment transport and deposition at the shallow-water delta front, where the effluent flow mixes with lake water. The distributary channels show characteristics of repeatedly occurred erosion, scouring, filling, and reoccupation. We argue that the depositional characteristics are associated with the changes in bed shear stress controlled by variation of flow velocity. Mouth bars are less likely to grow to a reasonable scale because of the seasonal scouring of extreme floods. Moreover, the lake flow potentially reworks the mouth bars. Consequently, mouth bar deposits were difficult to preserve as hydrocarbon reservoirs in ancient shallow-water delta.
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Letourmy, Yohan, Steven G. Driese, and Justin R. Sims. "Absence of evidence of climate-driven cycles in Carboniferous deposits of Joggins, Nova Scotia, Canada: influence of salt withdrawal tectonics on deposition and pedogenesis." Journal of Sedimentary Research 91, no. 2 (February 28, 2021): 167–85. http://dx.doi.org/10.2110/jsr.2020.78.
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ABSTRACT During the Late Paleozoic Ice Age, the fault-bounded equatorial Cumberland Basin of Nova Scotia experienced rapid subsidence, accumulating kilometer-thick fluvial sedimentary units derived from two highlands to the northwest and southeast. Major variations are recorded in the paleosols exposed at the Joggins Fossil Cliffs, ranging from oxidized and well-drained paleosols with recognizable vertic features to highly reduced organic-rich paleosols. These different soil lithologies suggest alternating conditions between well-drained floodplain environments and water saturation associated with overall poor soil development. Although halokinetic subsidence of the Cumberland Basin is known to have been operative during deposition of these units, previous research favored glacio-eustatic processes as the primary forcing mechanism of sedimentation. A total of 474 fluvial aggradational cycles were identified within a kilometer-thick interval and show a fluctuating accommodation history with a very abrupt nature. The series of fluvial aggradational cycles was used to develop threshold autoregressive models based on 1) their thickness, 2) their paleosol thickness, 3) their sandstone content, and 4) their paleosol-to-sandstone ratio. For each model, results suggest no evidence of statistically significant cyclicity, contradicting the hypothesis that fluvial sedimentation was mainly driven by glacio-eustatic cyclothems. Additionally, a total of 7 lithologies were recognized through 1,655 beds. Evaluation of 8 spherical semivariograms suggests no evidence for cyclicity in the frequency, order, or distribution of the data based on lithologies, although some covariance was found at distances between 550 and 750 m suggesting similar processes controlling sedimentation in the lower and upper Joggins Formation. The Cumberland Basin is known to have been rapidly subsiding, mainly because of ductile deformation of salt deposits in the deeper basinal units. Our results suggest that Joggins records tectonically induced ponding of a part of the sedimentary basin, allowing more extensive preservation of abundant coal and organic-rich units, as well as still-standing fossil forests exposed along the cliffs. These new results suggest that tectonic subsidence of the Cumberland Basin during the Late Paleozoic Ice Age was a more important driver of fluvial sedimentation than previously thought. This novel application of the TAR methodology provides a mathematical description of the sediment accumulation history of terrestrial basins when applied to conformable sedimentary successions, along with the means of linking paleosol development to climatic processes.
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Wang, Jiayi, Yitian Li, Li Pan, Zhiqiang Lai, and Shengqi Jian. "Study of the Sediment Transport Law in a Reverse-Slope Section of a Pressurized Pipeline." Water 12, no. 11 (October 29, 2020): 3042. http://dx.doi.org/10.3390/w12113042.
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This article reveals the change law of the head loss and critical deposition velocity during hydraulic transmission of a solid–liquid two-phase pipeline. This article also establishes a physical test model. A single variable is used to conduct the experimental research by changing the conditions of the pipeline flow rate, the sediment concentration, and the reverse slope degree. Based on an analysis of the test process, a new formula is proposed to determine the critical sedimentation rate of the pipeline that considers a change in the adverse slope. By analyzing the variation rule of the hydraulic slope of the pipeline sediment in different states and comparing the hydraulic slope of the horizontal pipeline and reverse pipeline in different states, different factors that influence head loss are revealed. Finally, the measured value of this test is compared with the Durand equation and the Worster equation. It was found that the measured value of this test was more similar to the Durand equation. This study not only provides theoretical support for sand removal in pipelines but also promotes sedimentation in reservoirs.
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Asnor, Asri S., Rahimi A. Rahman, and Saffuan W. Ahmad. "Causal Factors in Implementing Environmental Regulation: Evidence from the Erosion and Sediment Control Plan in Malaysia." International Journal of Engineering Technology and Sciences 7, no. 1 (January 14, 2021): 1–10. http://dx.doi.org/10.15282/http://dx.doi.org/10.15282/ijets.7.1.2020.1001.
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Erosion, and sedimentation can have a significant impact on the environment. Therefore, the Erosion and Sediment Control Plan (ESCP) is necessary to reduce those processes' adverse effects. Even though implementing ESCP is compulsory, we still have implementation issues in practice. This study aims to investigate the causal factors that are affecting ESCP implementation in Malaysia. To achieve that objective, data are collected through individual interviews with industry practitioners related to ESCP implementation. Then, the data are analyzed using thematic analysis. The challenges for implementing ESCP can be divided into two (2) internal and external challenges. Internal challenges consist of lack of competency, lack of knowledge, communication, attitude, awareness, planning, design, installation, and maintenance. In contrast, external challenges include management, financial, enforcement, and communication medium. This research contributes to the body of knowledge by providing insights into ESCP implementation, which could help develop policies and strategies to tackle the challenges. The findings of this research will help both researchers and practitioners to develop strategies that contribute to the sustainability of earth resources by reducing detachment of a portion of soil profiles from soil surfaces into soil particles (i.e., erosion); and transportation and deposition of soil particles (i.e., sedimentation) in construction projects.
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Fedor, Ferenc, Zoltán Máthé, Péter Ács, and Péter Koroncz. "New results of Boda Claystone research: Genesis, mineralogy, geochemistry, petrophysics." Geological Society, London, Special Publications 482, no. 1 (December 7, 2018): 75–92. http://dx.doi.org/10.1144/sp482.13.
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AbstractBoda Claystone is a very tight clayey rock with extreme low porosity and permeability, nano-size pores and small amounts of swelling clays. Due to this character it is ideal as a potential host rock for research into the possibilities of high-level waste deposition in geological formation. Though the research started more than 30 years ago, the genesis, the geotectonic history of the Boda Claystone Formation (BCF) and the geology of surrounding areas has only been sketched out recently. On the basis of research of the past few years the process of sedimentation of different blocks was able to be reconstructed. Equipment and methodological developments were needed for the investigation of reservoir geological and hydrodynamic behaviour of this rock, which began in the early 2000s. Based on them the pore structure and reservoir could be characterized in detail. Only theoretical approaches were available for the chemical composition of free porewater. Traditional water-extracting methods were not adaptable because of excessively low porosity and nano-scale pore size distribution. Hence, new ways have to be found for getting enough water for analysis. These new results of BCF research help to prepare more sophisticated and directed experiments, in which there is a great interest internationally.
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Giraudi, Carlo, Giulia Bodrato, Marianna Ricci Lucchi, Nicola Cipriani, Igor M. Villa, Biagio Giaccio, and Giovanni M. Zuppi. "Middle and late Pleistocene glaciations in the Campo Felice Basin (central Apennines, Italy)." Quaternary Research 75, no. 1 (January 2011): 219–30. http://dx.doi.org/10.1016/j.yqres.2010.06.006.
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AbstractThe present paper refers to research conducted in the tectonic-karst depression of Campo Felice in the central Apennines (Italy), in which glacial, alluvial and lacustrine sediments have been preserved. Stratigraphic interpretations of sediments underlying the Campo Felice Plain are based on evidence obtained from nine continuous-core boreholes. The boreholes reach a depth of 120 m and provide evidence of five sedimentation cycles separated by erosion surfaces. Each cycle is interpreted as an initial response to a mainly warm stage, characterized by low-energy alluvial and colluvial deposition, pedogenesis, and limited episodes of marsh formation. In turn, a mainly cold stage follows during which a lake formed, and glaciers developed and expanded, leading to deposition of glacial and fluvioglacial deposits. The chronological framework is established by eleven accelerator mass spectrometer 14C ages and three 39Ar–40Ar ages on leucites from interbedded tephra layers. These age determinations indicate five glacial advances that respectively occurred during marine oxygen isotope stages 2, 3–4, 6, 10 and 14.
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Aznury, Martha, Jaksen M. Amin, Abu Hasan, and Triadi Utomo. "The Digester Modification for Biogas Production from Palm Oil Mill Effluent by Batch System." MATEC Web of Conferences 156 (2018): 03037. http://dx.doi.org/10.1051/matecconf/201815603037.
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The purpose of this research is to determine the optimum production of biogas produced from the tuncated pyramid-shaped modification digester equipment on sedimentation tank and shaped beams on the tank fermentation batch. Pyramid-shaped sedimentation tank aiming for optimal deposition process, While the fermentation tank with beam-shaped used to produce biogas that is optimal. The raw material used is Palm Oil Mill Effluent. In the early stages of process is carried out the sedimentation in the first digester tank at a flow rate of 6 liters/minute and then observing the time stayed for 24 hours. POME flowed into the second digester tank to run into fermentation process by adding active microbial seed to produce biogas. After fermentation is complete, streamed to third digester tank to experience water treatment stage before being released into the environment. COD content test value obtained after the processing of 100 mg/l, while the BOD value is 30.9 mg/l. The percentage of methane gas obtained from starter concentration of 30%, ie 9.82% mol for fermentation time of 10 days, while the fermentation period of 20 days is 15.8 mol%. The production of methane gas obtained for the optimum fermentation period of 30 days ie 33.19% mol. For days 31 through 40, the production of biogas run into highs and caused due to the substrate in the digester began to run out and most of the substrate has not been fermented.
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Tsekhovskii, Yu G., В. А. Bogatyrev, and V. V. Zhukov. "Lithogenesis on peneplaned сontinented platform of Kazakhstan and Siberia during the Cretaceous-Paleogene boundary epoch." LITOSFERA, no. 1 (March 17, 2019): 5–29. http://dx.doi.org/10.24930/1681-9004-2019-19-1-5-29.
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Research subject. The inner structure, composition, and genesis of the poorly studied formation of weathering crusts are studied with reference to peneplaned platform territories in Kazakhstan and Siberia during the Cretaceous-Paleogene boundary epoch. This formation hosts many valuable minerals, such as bauxite, iron ores, refractory clays, etc., thereby attracting much research attention. Materials and methods. The results were obtained following a series of long-term studies and a review of available data recently obtained on the weathering crust formation in the territories of Kazakhstan and Siberia. The methods of lithological facies and formation analysis were used, along with the separate studies of the eluvial material – weathering crusts in erosion areas and intra-formation weathering horizons in accumulation areas. Results. The weathering crust formation in the study area is shown to comprise two kinds of rock mass: siliceous-kaolinite ones forming erosion-tectonic depressions and kaolinite-bauxite ones forming karst depressions. The inner structure, composition, and genesis of both rock mass units are studied in detail, with all their sedimentation stages being analyzed. The sedimentation process is traced from the preparation of the material in weathering crusts at erosion areas to the deposition of this material and its post-sedimentation transformations (mostly with the involvement of subaerial diagenesis) in depressions. Detailed information is presented on subaerial diagenesis, which deserves further studies. Conclusions. This publication is the frst to present detailed information on the inner structure, composition and genesis of the ancient formation of weathering crusts produced in hot humid climate on peneplaned land territories. It is confrmed that the processes underpinning this formation – starting with the preparation of the material and ending with its accumulation in depressions – were different from those typical of modern orogenic environments. This conclusion extends the current understanding of the forms and nature of ancient lithogenetic processes.
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Ruban, Dmitry A. "The siliciclastics/carbonates shift in the Jurassic of the Western Caucasus (central northern Neo-Tethys): reconsidering research over the last 50 years." Geologos 25, no. 2 (August 1, 2019): 153–62. http://dx.doi.org/10.2478/logos-2019-0014.
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Abstract A chain of carbonate platforms evolved in the northern Neo-Tethys during the Late Jurassic, but current knowledge remains incomplete as long as data from several larger regions, such as the Western Caucasus, are not included. In order to fill this gap, it is here suggested to reconsider the information accumulated chiefly during Soviet times. Although these data are too general, they still matter with regard to some regional characteristics and tentative interpretations. Available data on the spatio-temporal distribution of Bajocian-Callovian sedimentary rocks are summarised in a novel way which permits documentation of depositional trends at six representative localities in the Western Caucasus. The extent of the carbonate platform increased at two localities since the Late Callovian and at a third since the Middle Oxfordian. Three additional sites were characterised either by non-deposition or deep-marine sedimentation. The onset of carbonate platform development marked a remarkable shift from chiefly siliciclastic to carbonate deposition, although this event was not sudden everywhere. The Bathonian pulse of tectonic activity, coupled with the eustatic sea level rise, allowed shelves to expand during the Callovian-Oxfordian, with a reduction in siliciclastic input from islands and sea-water that became well oxygenated and warmer. These conditions were conducive to biogenic carbonate production, allowing the carbonate platform to expand subsequently.
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Cheremisska, O. M., and Yu V. Cheremissky. "Lithofacial and paleogeographic analysis of the Burdigallian-Langhian formations of the Ukrainian Carpathian Foredeep." Journal of Geology, Geography and Geoecology 28, no. 1 (April 16, 2019): 19–28. http://dx.doi.org/10.15421/111903.
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This paper addresses issues related to the complexity of the geological structure of the Burdigallian-Langhian sediments of the Stebnyk suite, which wereformed in the Carpathian segment of Paratethys. The correlation of stratigraphic sections, based on a detailed description of the most complete sediments of the indigenous outcrops of the Stebnyk suite in the Sambir Unit of the Pre-Carpathian Foredeep, has been carried out. It was established that the sediments belong to a single tectono-sedimentation cyclic, the formation of which began with the deposition of red-coloured sediments and ended with the deposition of salt-bearing formations, which indicates the final closure of the Paratethys. A series of lithological columns was constructed taking into account the disjunctive and plicating faults, which allowed us to derive the true thickness of the Stebnyk suite deposits and determine its lithofacial structure. The results obtained became the basis for the construction of a lithological scheme for the distribution of lithofacies and a paleooceanographic sedimentation model of the research area. The aim of this work is to create a reconstruction of the environment of sedimentation in the Burdigallian-Langhian Age in the Sambir Unit of the Inner part of the Pre-Carpathian Foredeep. To obtain the results, the actual material obtained during the field observations was analyzed with the help of a complex of lithology-facial, geodynamical and petrographic methods. Due to the absence of the reliable paleontological data on deposits of the Miocene Stebnyk suite of the PreCarpathian basin, an attempt was made to partition the Stebnyk sedimentary sequence on lithological and formation features, basedon the author's research and with incorporation of new materials of paleooceanography of the Carpathian segment of the Paratethys. On the basis of paleooceanographic data, connected with formation of sedimentary strata of Stebnyk suite (Carpathian basin), the latter can be attributed to the red-coloured formation of foothill plains and deltas. Taking into account the data of the researchers and their own observations, one can come to the conclusion that the age of the sediments, mapped on existing geological maps as Vorotyshcha suite in considerable areas of Sambir Unit (near the villages of Krasne, Pidlyvche, Lysovychi) is questionable. This conception required the stratification of deposits formed on the stage of sedimentogenesis in the Miocene within the studied segment of the Central Paratethys. For the first time for depositions of this age, the scheme of the palaeoceanographic situation and a lithological-facial model of the sedimentation environment with the reduction of the true thickness of sediments was constructed. The Burdigallian-Langhian deposits were formed under conditions of lacustrine-alluvial plains of arid climate, symbolizing the final closure of the Central Paratethys. The presence of a detailed model for the formation of Burdigallian-Langhian deposits allows us to identify a number of criteria for the search for minerals.
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Hanke, Petra U., and Christopher R. Dickman. "Sniffing out the stakes: hair-snares for wild cats in arid environments." Wildlife Research 40, no. 1 (2013): 45. http://dx.doi.org/10.1071/wr12210.
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Context Wild cats (Felis spp.) are difficult to monitor because of their cryptic lifestyle and usually low numbers. Hair-snaring is a promising non-invasive method being used increasingly to estimate mammal populations. Aims Our aim was to carry out pilot trials of a simple hair-snare designed to capture hair from wild cats in arid environments. Methods Roughened wooden stakes were set at multiple sites on the crests of sand dunes and in swales in western Queensland, Australia, and in mostly sandy habitats of the Namib and Kalahari Deserts, Namibia. In Australia, stakes were sprayed with cat urine, extracts of catnip or valerian herbs as lures, or left untreated; in Namibia, alternate stakes were sprayed with a food lure of tuna emulsion oil. The stakes were checked for hair, usually daily, for 2–14 days, and the surrounding ground was inspected for tracks. Remote cameras also were used at some sites to confirm the identity of visitors to stakes. Key results In Australia, feral cats (Felis catus) were attracted to, and left hairs on, stakes sprayed with cat urine six times more frequently than to unsprayed stakes irrespective of whether snares were on dune crests or in swales, and showed no response to catnip or valerian. Tracks and photos showed that cats, dingoes or wild dogs (Canis lupus ssp.) and foxes (Vulpes vulpes) also approached and sniffed the stakes. In Namibia, F. catus, F. lybica and F. nigripes left hair on stakes, with deposition rates two and a half-fold higher at stakes with the food lure than without it. At least five other species of predators visited the hair-snare sites. Conclusions Simple wooden stakes provide a cheap and simple method of snaring hairs from wild cats, especially if used in conjunction with appropriate lures. Our results broadly support previous work, and extend the utility of the method to different Felis spp. in arid habitats. Implications Further research is needed on snares to investigate the seasonal efficiency of different lures. If DNA also is to be extracted to identify individuals, more work is needed to confirm that snares yield hair of sufficient quality to allow this.
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Kent, M., N. W. Owen, P. Dale, R. M. Newnham, and T. M. Giles. "Studies of vegetation burial: a focus for biogeography and biogeomorphology?" Progress in Physical Geography: Earth and Environment 25, no. 4 (December 2001): 455–82. http://dx.doi.org/10.1177/030913330102500401.
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This paper examines the literature on research into the effects of burial by deposition of blown sand, volcanic deposits (tephra, lavas and lahars) or fluvial sediment on vegetation and the subsequent capacity of the vegetation for survival and regeneration. Research on this topic involves the understanding and skills of the biogeographer, the ecologist and the geomorpholo-gist and represents a potentially very interesting area for integration between these areas of physical geography. Burial is closely linked to concepts of plant succession and pedogenesis. A general model of burial stress is presented that shows how types of stress are linked to the burial environment and the characteristics of the burial event, in particular the magnitude and frequency. The importance of elasticity of response of species to burial is vital, as demonstrated by the evolution of certain species, such as those of the genus Ammophila in sand dunes that appear to respond positively to the burial process. Research into burial by dust deposition, by volcanic tephra and lavas, by sand in coastal and lake dune environments, in desert environments and by alluvium and ‘run-on’ following hydro-logical events are reviewed in turn. The significance of burial to palaeoenvironmental and palaeoecological research is then demonstrated by reference to machair sand dune stratification in the Outer Hebrides and vegetation damage and burial following proximal volcanic impacts in New Zealand. Finally, methods of experimental research into burial in both the field and in the greenhouse are summarized and the conclusion stresses the need for more holistic approaches to the study of burial that link the biogeographical aspects of plant ecophysiology and both individual species and community ecology to the various geomorphic processes of deposition and sedimentation.
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Turner, Bryan W., Carlos E. Molinares-Blanco, and Roger M. Slatt. "Chemostratigraphic, palynostratigraphic, and sequence stratigraphic analysis of the Woodford Shale, Wyche Farm Quarry, Pontotoc County, Oklahoma." Interpretation 3, no. 1 (February 1, 2015): SH1—SH9. http://dx.doi.org/10.1190/int-2014-0089.1.
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Understanding mudrocks and shale reservoirs has become a significant area of interest within industry and academia in recent years. Of particular interest is understanding the pervasive variability present within these units. This variability became apparent when conventional approaches, such as lithostratigraphic analysis and well log correlation, were coupled with recent developments in palynostratigraphy and chemostratigraphy. A single shallow Woodford Shale research core in the western Arkoma Basin from Pontotoc County, Oklahoma, was used to identify three scales of stratigraphic cyclicity. By comparing the relative abundances of continental sourced pollen and spores to marine-derived acritarchs over a stratigraphic interval, it was possible to extrapolate the overall trends in shoreline trajectory. Conventional well log analysis, such as gamma ray logs, provided a balanced understanding of the interplay between localized changes in sedimentation and regional shifts in the stratigraphic base level, in addition to providing a means to tie these analyses to extensive subsurface data sets. Chemostratigraphic correlations resolved subtle, but stratigraphically significant, shifts in localized patterns in sedimentation. Using these approaches, the Lower and Middle Woodford Shale can be divided into four chemostratigraphic parasequences within a transgressive systems tract defined by well log and core analysis. The Upper Woodford can be separated into an additional four chemostratigraphic parasequences within a highstand systems tract. Chemostratigraphic data also revealed the changing bottom water conditions present at the time of deposition, with a period of localized anoxic conditions recorded in the Lower and Upper Woodford in this part of the basin. These localized changes in sedimentation and environmental conditions can be nested into two longer term regional transgressions and regressions.
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Amijaya, Donatus Hendra, Najibatul Adibah, and Ahmad Z. A. Ansory. "Lithofacies and Sedimentation of Organic Matter in Fine Grained Rocks of Nanggulan Formation in Kulon Progo, Yogyakarta." Journal of Applied Geology 1, no. 2 (July 26, 2016): 82. http://dx.doi.org/10.22146/jag.26964.
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Fine grained rocks especially shale play a significant role in shale hydrocarbon system. Research on Eocene Nanggulan shale becomes an interest lately since this shale is considered as prospective interval for shale gas source. It potentially contains significant organic matter because coaly sediment is found in this formation as well. Nanggulan Formation fine grained rocks was deposited in various depositional environment from estuary – shallow marine. This paper integrates the result of lithofacies and depositional environment analysis with organic geochemical data to understand the sedimentation process of organic matter. Samples were taken from cores. The result of 14 geochemically analysed samples shows Total Organic Carbon (TOC) content between 0.36–1.00 % for fin e grained rocks (shales) and 12.80 % for coaly shales. Nine samples are categorized as fair and 2 samples are categorized as good source rock. The depositional environment of Nanggulan Formation sediment, which was shallow marine at Late Eocene and estuary (salt marsh) at Early Eocene, produced sediment with higher TOC. Whereas the deposition of sediment in estuary (tidal flat) at Middle Eocene produced lower content of TOC. Vulcanic activity at Middle Eocene also caused less organic material preservation because it produced abundant inorganic material.
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Tafarojnoruz, Ali, and Ahmad Sharafati. "New formulations for prediction of velocity at limit of deposition in storm sewers based on a stochastic technique." Water Science and Technology 81, no. 12 (June 15, 2020): 2634–49. http://dx.doi.org/10.2166/wst.2020.321.
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Abstract Sedimentation in storm sewers strongly depends on velocity at limit of deposition. This study provides application of a novel stochastic-based model to predict the densimetric Froude number in sewer pipes. In this way, the generalized likelihood uncertainty estimation (GLUE) is used to develop two parametric equations, called GLUE-based four-parameter and GLUE-based two-parameter (GBTP) models to enhance the prediction accuracy of the velocity at the limit of deposition. A number of performance indices are calculated in training and testing phases to compare the developed models with the conventional regression-based equations available in the literature. Based on the obtained performance indices and some graphical techniques, the research findings confirm that a significant enhancement in prediction performance is achieved through the proposed GBTP compared with the previously developed formulas in the literature. To make a quantified comparison between the established and literature models, an index, called improvement index (IM), is computed. This index is a resultant of all the selected indices, and this indicator demonstrates that GBTP is capable of providing the most performance improvement in both training () and testing () phases, comparing with a well-known formula in this context.
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Darquenne, Chantal, Maria G. Borja, Jessica M. Oakes, Ellen C. Breen, I. Mark Olfert, Miriam Scadeng, and G. Kim Prisk. "Increase in relative deposition of fine particles in the rat lung periphery in the absence of gravity." Journal of Applied Physiology 117, no. 8 (October 15, 2014): 880–86. http://dx.doi.org/10.1152/japplphysiol.00298.2014.
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While it is well recognized that pulmonary deposition of inhaled particles is lowered in microgravity (μG) compared with gravity on the ground (1G), the absence of sedimentation causes fine particles to penetrate deeper in the lung in μG. Using quantitative magnetic resonance imaging (MRI), we determined the effect of gravity on peripheral deposition (DEPperipheral) of fine particles. Aerosolized 0.95-μm-diameter ferric oxide particles were delivered to spontaneously breathing rats placed in plethysmographic chambers both in μG aboard the NASA Microgravity Research Aircraft and at 1G. Following exposure, lungs were perfusion fixed, fluid filled, and imaged in a 3T MR scanner. The MR signal decay rate, R2*, was measured in each voxel of the left lung from which particle deposition (DEP) was determined based on a calibration curve. Regional deposition was assessed by comparing DEP between the outer (DEPperipheral) and inner (DEPcentral) areas on each slice, and expressed as the central-to-peripheral ratio. Total lung deposition tended to be lower in μG compared with 1G (1.01 ± 0.52 vs. 1.43 ± 0.52 μg/ml, P = 0.1). In μG, DEPperipheral was larger than DEPcentral ( P < 0.03), while, in 1G, DEPperipheral was not significantly different from DEPcentral. Finally, central-to-peripheral ratio was significantly less in μG than in 1G ( P ≤ 0.05). These data show a larger fraction of fine particles depositing peripherally in μG than in 1G, likely beyond the large- and medium-sized airways. Although not measured, the difference in the spatial distribution of deposited particles between μG and 1G could also affect particle retention rates, with an increase in retention for particles deposited more peripherally.
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Browning, Trevor N., and Derek E. Sawyer. "Erosion and deposition vulnerability of small (<5,000 km2) tropical islands." PLOS ONE 16, no. 9 (September 16, 2021): e0253080. http://dx.doi.org/10.1371/journal.pone.0253080.
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The tropics are naturally vulnerable to watershed erosion. This region is rapidly growing (projected to be 50% of the global population by 2050) which exacerbates erosional issues by the subsequent land use change. The issue is particularly of interest on the many (~45,000) small tropical (<5,000 km2) islands, and their >115M residents, where ecotourism and sediment intolerant ecosystems such as coral reefs are the main driver of their economies. However, vulnerability to erosion and deposition is poorly quantified in these regions due to the misclassification or exclusion of small islands in coarse global analyses. We use the only vulnerability assessment method that connects watershed erosion and coastal deposition to compare locally sourced, high-resolution datasets (5 x 5 m) to satellite-collected, remotely sensed low-resolution datasets (463 x 463 m). We find that on the island scale (~52 km2) the difference in vulnerability calculated by the two methods is minor. On the watershed scale however, low-resolution datasets fail to accurately demonstrate watershed and coastal deposition vulnerability when compared to high-resolution analysis. Specifically, we find that anthropogenic development (roads and buildings) is poorly constrained at a global scale. Structures and roads are difficult to identify in heavily forested regions using satellite algorithms and the rapid, ongoing rate of development aggravates the issue. We recommend that end-users of this method obtain locally sourced anthropogenic development datasets for the best results while using low resolution datasets for the other variables. Fortunately, anthropogenic development data can be easily collected using community-based research or identified using satellite imagery by any level of user. Using high-resolution results, we identify a development trend across St. John and regions that are both high risk and possible targets for future development. Previously published modeled and measured sedimentation rates demonstrate the method is accurate when using low-resolution or high-resolution data but, anthropogenic development, watershed slope, and earthquake probability datasets should be of the highest resolution depending on the region specified.
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Li, Yanfang, Hua Zhang, and Cheng Tang. "A review of possible pathways of marine microplastics transport in the ocean." Anthropocene Coasts 3, no. 1 (January 1, 2020): 6–13. http://dx.doi.org/10.1139/anc-2018-0030.
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Marine microplastics pollution has been a new challenge to marine environmental protection. The research results have shown that microplastics exist everywhere in the ocean. However, understanding of the transport of microplastics in the ocean, including coastal zones, is not clear. This paper provides a holistic overview of the modelling of microplastic transportation. The transport processes are complex, including surface drifting, vertical mixing, beaching, and settling. Besides the dynamic conditions of oceans, the transportation of microplastics is influenced by their physical characteristics, such as size, shape, and density. For buoyant particles, a Lagrange track model is used to simulate the surface drift process, considering current, windage effect, and Stokes drift. It is difficult to observe the vertical mixing process of microplastics because of their small size (<5 mm), therefore the parameters of the vertical mixing process in the model are still less known. Large accumulation of microplastics in sediments may be a result of settlement and entrainment. Also, biofilm formation can increase their density and thus, deposition. Considering sedimentation of microplastics is somewhat different from sediment deposition, some primary parameters (e.g., diffusivity, Stokes-drift, settling rate, biofouling rate) are required in future studies to better understand the transport of marine microplastics.
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Li, Tao, Jun-hua Zhang, Guoming Gao, and Huaibao Ma. "Variation on sandbar of tributary in Xiaolangdi Reservoir on Yellow River, China." MATEC Web of Conferences 246 (2018): 01019. http://dx.doi.org/10.1051/matecconf/201824601019.
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Sandbar development would stop the water and sediment exchange between main river and tributary and even influence the normal reservoir opeartion. From the surveyed data of reservoir built many years ago, it shows that when there is a bar in tributary mouth, the tributary volume below the bar will become nullification during the period of flood control or water and sediment regulation of reservoir. There are more tributaries in Xiaolangdi reservoir than the others that it occupies 41.3% of the total initial volume of tributary volume. Obviously, the effective use of tributary volume has been important influenced by comprehensive utilization efficiency of reservoir scheduling, such as flood control, sedimentation reduction and comprehensive utilization. Results of Xiaolangdi Reservoir mobile-bed physical model experiments show that tributary is equivalent to lateral extension of river bed, the tributary intrusion deposition process have strongly relations with the factors, such as original topography, river bed deposition shape and its regime, process with input discharge and input sediment, and method of reservoir regulation. The variation trends of main river and tributary terrain forecasted by model test are basically in accordance with field surveyed data. The results could be used for research, design, and forecasting of reservoirs in sediment-laden river.
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Funaki, Hironori, Hiroki Hagiwara, and Tadahiko Tsuruta. "The Behavior of Radiocaesium Deposited in an Upland Reservoir After the Fukushima Nuclear Power Plant Accident." MRS Proceedings 1665 (2014): 165–70. http://dx.doi.org/10.1557/opl.2014.642.
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ABSTRACTIn the autumn of 2012, the Japan Atomic Energy Agency (JAEA) launched a new research project named F-TRACE (Long-Term Assessment of Transport of Radioactive Contaminant in the Environment of Fukushima). The aims of this project are to develop a system for prediction of radiation exposure, taking into consideration the transport, deposition, and remobilization behavior of radiocaesium (RCs) from the highest contaminated mountain forests, down through the biosphere, before deposition in a number of different aquatic systems. Especially, it is important to understand balances of suspended and deposited particles and RCs inventory in inflow water, discharge water and bottom sediments of an upland reservoir. In this paper, we describe current research activities performed by JAEA at the Ogi Reservoir, Fukushima prefecture, Japan.According to our analyses the specific sediment yield and the average rate of storage capacity loss at the Ogi Reservoir are 210 m3 km-2 year-1 and 0.15 % year-1, respectively. The vertical distribution of RCs exhibits clear peaks at several sites in the reservoir formed by deposition of eroded soil particles from the catchment that were contaminated by accident fallout. Above the depth of each of the RCs peaks, the distribution of RCs was found to be variable with depth, with concentrations ranging over five orders of magnitude for a single core. The peaks in the sedimentation profiles are probably formed from eroded soil particles entering the reservoir from the surrounding contaminated watershed (most probably during storm events). Results from grain size analyses suggest that contaminated fine sediment tends to be deposited thickly within deeper parts of the reservoir. In addition, above the depth of RCs peaks at these deeper sites, the concentration of RCs approximately increased or decreased as the proportion of fine sediments increased or decreased. However, some fine particles are possibly discharged downstream during operational releases from the dam.
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Pu, Guang Yue, Yong Xia Bu, Chun Lei Pan, and Hong Wei Liu. "Study on Parameters of Slurry Pipeline Transportation Technology in Grade." Applied Mechanics and Materials 687-691 (November 2014): 556–59. http://dx.doi.org/10.4028/www.scientific.net/amm.687-691.556.
Full textAbstract:
In generally, there are multiple factories. According to mining areas, it supplies different quality iron ore concentrate. And according to the unique requirements of owners, different grades concentrate cannot be confused. Therefore, the grade of slurry pipeline transportation is needed to be used. When in the study of grade transmission, we must focus on Hydraulic characteristics of solid-liquid two-phase for different quality of iron ore concentrate. Slurry concentration and Critical velocity of flow is especially important. Research shows that the deposition rate of laminar or turbulent transition velocity is higher than the occasion when the slurry has concentration, so the minimum operating speed is controlled by sedimentation; the concentration lower limit is 62%. If the concentration is over 68%, the yield stress of slurry will increase, and the pipeline pressure will drop, which is very sensitive to slight changes in concentration. Therefore, the solid weight concentration range is 62% to 68%,as the selection range of design.
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Lu, Yongjun, Rongyao Ji, and Liqin Zuo. "STABILITY AND ENGINEERING EFFECT OF SHOALS AND CHANNELS IN CAOFEIDIAN DEEP-WATER HARBOR AREA, CHINA." Coastal Engineering Proceedings 1, no. 32 (January 19, 2011): 38. http://dx.doi.org/10.9753/icce.v32.management.38.
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Caofeidian sea area is the only natural site suitable for building a large-sized berth of 300 000 tons without excavation of waterways and harbor basins in Bohai Bay. In Caofeidian harbor area, the stability of the shoals-inlets coastal system under natural conditions is a key point. The harbor could be developed only if the coastal system is stable. In this paper the characteristics of waves, tidal currents, sedimentation and seabed evolution in the Caofeidian shoal area is briefly described, and the trend of stability of shoals and channels is predicted based on research on the coastal system formation. Engineering effect of some projects, such as the dam linking the Caofeidian Island and the coastline, the shoal reclamation and ore terminal construction, is also studied. The analysis show that deposition and erosion of the seabed in front of Caofeidian foreland will reach its equilibrium in 2～3 years after the implementation of the proposed scheme.
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Rafsanjani, Hardhi. "Sediment Transport Analysis of Sesayap River, Malinau District, North Kalimantan." Journal of the Civil Engineering Forum 3, no. 3 (September 18, 2017): 149. http://dx.doi.org/10.22146/jcef.27239.
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River could have a very important role in improving the economy of a country when it is correctly and properly utilized. Nevertheless, rivers in Indonesia also have various problems, i.e. erosion and sedimentation which occur in many Indonesian rivers, one of it being the Sesayap River. Because of these problems, it is very important to do analysis on bed load transport, in order to find its amount in the existing river, so that optimal handling on the occurring erosion and sedimentation problems could be performed. This research aimed to obtain the amount of bed load transport in Sesayap River, and then compare it to the field condition. The approaches used in this bed load transport analysis were Einstein approach and Frijlink approach, with data required for the analysis, which was water level elevation, topography data, and sediment gradation data. Based on the result of conducted bed load transport analysis, the bed load transport analysis result in Seluwing area was higher than in the Port area. Therefore, sediment deposition or sedimentation would occur in the river segment on between both locations. Qualitatively or tendentiously, the above results showed consistency with what actually happened, or observed, in the field. If it assumed that the equivalent diameter of bed load is 8 mm, the total of bed load transport on Seluwing area and Port area with Einstein approach are 1,582,263 m3 and 1,219,181 m3. Therefore, the sedimentary deposit per day could be calculated by calculating difference of bed load transport volume divided with total of the calculation day; which resulted sedimentary deposit per day of 2,859 m3. Whereas by using the Frijlink approach, the total of bed load transport on Seluwing area and Port area were of 1,391,940 m3 and 1,080,200 m3, and sedimentary deposit per day of 2,455m3. Based on the results, in order to normalize the Sesayap River, the dredging needed is 2,859m3/day based on Einstein approach and 2,455m3/day based on Frijlink approach.
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Langendoen, E. J., R. R. Wells, M. E. Ursic, D. A. N. Vieira, and S. M. Dabney. "Evaluating sediment transport capacity relationships for use in ephemeral gully erosion models." Proceedings of the International Association of Hydrological Sciences 367 (March 3, 2015): 128–33. http://dx.doi.org/10.5194/piahs-367-128-2015.
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Abstract. On cropland, ephemeral gully erosion in the USA may contribute up to 40% of the sediment delivered to the edge of the field. Well-tested, physically- and process-based tools for field and watershed scale prediction of gully erosion are lacking due to the fact that the complex nature of migrating headcuts is poorly understood. Understanding sediment transport capacity downstream of migrating headcuts is essential, as sediment deposition often leads to temporary storage that controls downstream water elevation, which in turn affects the rate of headcut migration. Current process-based gully erosion prediction technology used by the Agricultural Research Service (ARS) is based on characterizing the headcut migration rate, which requires the deposition depth as input to the model. Alternatively, the deposition depth can be calculated if downstream sediment transport capacity can be predicted. Data collected at the ARS-National Sedimentation Laboratory were used to test existing sediment transport relationships for the five sediment size classes (clay, silt, sand, small aggregates, large aggregates) typically used in ARS soil erosion models. The results show that the transport rate can be satisfactorily predicted for sand and large aggregate size fractions using common transport relationships based on unit stream power theory. The fractional content of the sand and large aggregate size classes can be computed using standard relationships, which are based on soil texture, previously developed by ARS. The transport of clays, silts and small aggregates is detachment limited and must therefore be computed using improved soil detachment relationships for ephemeral gullies.
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Rasmussen, Peter, Kaj Strand Petersen, and David B. Ryves. "Environmental change in Danish marine waters during the Roman Warm Period inferred from mollusc data." Geological Survey of Denmark and Greenland (GEUS) Bulletin 13 (October 12, 2007): 21–24. http://dx.doi.org/10.34194/geusb.v13.4967.
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Modern geological research into the late and postglacial history of the inner Danish waters (i.e. Kattegat, Bælthavet and Øresund, plus the adjoining fjords and estuaries) began at the turn of the last century. Since then most investigations have focused on the timing of the initial marine inundation of the area, the early to mid-Holocene changes in land–sea confi- guration and sea level changes during the mid-Holocene Littorina period. Research on the late Holocene marine environment has received less emphasis, undoubtedly due to problems in finding continuous marine sediment records, as sedimentation in large areas of the Danish waters seems to have been characterised by complex spatial and temporal patterns of deposition and non-deposition (e.g. Lykke-An dersen et al. 1993). In an ongoing project we aim to ex- plore the continuous development of Dan ish coastal environments over the last 9000 years using a variety of proxy data, including molluscs, dia toms, foramini fera, algal pigments, plant macrofossils and physical properties of sedi ments. The project spans both environmental and cultural history, and addresses the important links between them, as the nature of the coastal environment has exerted major influences on cultural and societal expression and activity from Mesol ithic to modern times. This paper presents some of the first results from the project concerning environmental changes in the Roman Warm Period (c. 2000–1600 years B.P.) as shown by changes in molluscan faunas at two coring sites in Horsens Fjord and Tem pelkrog in southern Isefjord (Fig. 1).
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Farrington, John, Edward Overton, and Uta Passow. "Biogeochemical Processes Affecting the Fate of Discharged Deepwater Horizon Gas and Oil: New Insights and Remaining Gaps in Our Understanding." Oceanography 34, no. 1 (March 1, 2021): 76–97. http://dx.doi.org/10.5670/oceanog.2021.118.
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Research funded under the Gulf of Mexico Research Initiative provided new insights into the biogeochemical processes influencing the fate of petroleum chemicals entering the Gulf of Mexico from the Deepwater Horizon (DWH) accident. This overview of that work is based on detailed recent reviews of aspects of the biogeochemistry as well as on activities supported by the US Natural Resource Damage Assessment. The main topics presented here are distribution of hydrocarbons in the water column; the role of photo-oxidation of petroleum compounds at the air-sea interface; the role of particulates in the fate of the DWH hydrocarbons, especially marine oil snow (MOS) and marine oil snow sedimentation and flocculent accumulation (MOSSFA); oil deposition and accumulation in sediments; and fate of oil on beaches and in marshes. A brief discussion of bioaccumulation is also included. Microbial degradation is addressed in a separate paper in this special issue of Oceanography. Important future research recommendations include: conduct a more robust assessment of the mass balance of various chemical groupings and even individual chemicals during specific time intervals; seek a better understanding of the roles of photo-oxidation products, MOS, and MOSSFA and their relationships to microbial degradation; and determine the fates of the insoluble highly degraded and viscous oil residues in the environment.
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Wójcicki, Krzysztof. "The Valley-Fill Deposits of the Kłodnica River (Southern Poland): Environmental Drivers of Facies Changes from the Late Vistulian Through the Holocene." Geochronometria 35, no. -1 (January 1, 2010): 49–66. http://dx.doi.org/10.2478/v10003-010-0005-5.
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The Valley-Fill Deposits of the Kłodnica River (Southern Poland): Environmental Drivers of Facies Changes from the Late Vistulian Through the HoloceneLithological analyses and radiocarbon dating were used to elucidate the patterns and controls of Late Quaternary valley floor development of the Kłodnica River, the Upper Odra Basin. The research results were discussed with data obtained from valleys of rivers draining piedmont basins and highlands of southern Poland. In consequence, five stages of morpho-sedimentary evolution of the Kłodnica valley were distinguished. In the Late Vistulian a large-scale deposition of channel alluvium took place in the conditions of high river discharges. This sedimentary style probably still existed in the Early Pre-Boreal as long as open grass communities survived in the Kłodnica catchment. The next phase, in the Late Pre-Boreal and Boreal, is characterized by a significant increase in accumulation rate of biochemical facies. The considerable restriction of minerogenic deposition was connected with widespread of forest and gradual limitation of the river discharges. The third stage began at the decline of the Boreal and was defined by decrease of accumulation rate or even biogenic accumulation break. Synchronously, periodic increases of fluvial activity were noticed in the form of cutoffs of meander loops and overbank deposition in oxbows. The beginning of the fourth period took place not earlier than in the Early Sub-Boreal. This stage was distinguished by renewed peat growth/increase in biochemical accumulation rate and periodic increase in alluviation, generally taking place in the conditions of low channel-forming flows. The latest phase (from the Middle Sub-Atlantic till now) is characterized by common initiation of slope deposition and a rapid increase in fluvial sedimentation, especially overbank and tributary fan facies. An increase in minerogenic deposition occurred in response to human impact, which became more significant from the Roman Period and occurred on a large scale from the early Middle Ages. Older settlement phases, including intense settlement from the Hallstatt Period, were not clearly recorded in the Kłodnica valley fill.