Search results for: soil surface settlement
8820 Modeling Floodplain Vegetation Response to Groundwater Variability Using ArcSWAT Hydrological Model, Moderate Resolution Imaging Spectroradiometer - Normalised Difference Vegetation Index Data, and Machine Learning
Authors: Newton Muhury, Armando A. Apan, Tek Maraseni
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This study modelled the relationships between vegetation response and available water below the soil surface using the Terra’s Moderate Resolution Imaging Spectroradiometer (MODIS) generated Normalised Difference Vegetation Index (NDVI) and soil water content (SWC) data. The Soil & Water Assessment Tool (SWAT) interface known as ArcSWAT was used in ArcGIS for the groundwater analysis. The SWAT model was calibrated and validated in SWAT-CUP software using 10 years (2001-2010) of monthly streamflow data. The average Nash-Sutcliffe Efficiency during the calibration and validation was 0.54 and 0.51, respectively, indicating that the model performances were good. Twenty years (2001-2020) of monthly MODIS NDVI data for three different types of vegetation (forest, shrub, and grass) and soil water content for 43 sub-basins were analysed using the WEKA, machine learning tool with a selection of two supervised machine learning algorithms, i.e., support vector machine (SVM) and random forest (RF). The modelling results show that different types of vegetation response and soil water content vary in the dry and wet season. For example, the model generated high positive relationships (r=0.76, 0.73, and 0.81) between the measured and predicted NDVI values of all vegetation in the study area against the groundwater flow (GW), soil water content (SWC), and the combination of these two variables, respectively, during the dry season. However, these relationships were reduced by 36.8% (r=0.48) and 13.6% (r=0.63) against GW and SWC, respectively, in the wet season. On the other hand, the model predicted a moderate positive relationship (r=0.63) between shrub vegetation type and soil water content during the dry season, which was reduced by 31.7% (r=0.43) during the wet season. Our models also predicted that vegetation in the top location (upper part) of the sub-basin is highly responsive to GW and SWC (r=0.78, and 0.70) during the dry season. The results of this study indicate the study region is suitable for seasonal crop production in dry season. Moreover, the results predicted that the growth of vegetation in the top-point location is highly dependent on groundwater flow in both dry and wet seasons, and any instability or long-term drought can negatively affect these floodplain vegetation communities. This study has enriched our knowledge of vegetation responses to groundwater in each season, which will facilitate better floodplain vegetation management.Keywords: ArcSWAT, machine learning, floodplain vegetation, MODIS NDVI, groundwater
Procedia PDF Downloads 1238819 Geoelectrical Investigation Around Bomo Area, Kaduna State, Nigeria
Authors: B. S. Jatau, Baba Adama, S. I. Fadele
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Electrical resistivity investigation was carried out around Bomo area, Zaria, Kaduna state in order to study the subsurface geologic layer with a view of determining the depth to the bedrock and thickness of the geologic layers. Vertical Electrical Sounding (VES) using Schlumberger array was carried out at fifteen (15) VES stations. ABEM terrameter (SAS 300) was used for the data acquisition. The field data obtained have been analyzed using computer software (IPI2win) which gives an automatic interpretation of the apparent resistivity. The VES results revealed heterogeneous nature of the subsurface geological sequence. The geologic sequence beneath the study area is composed of hard pan top soil (clayey and sandy-lateritic), weathered layer, partly weathered or fractured basement and fresh basement. The resistivity value for the topsoil layer varies from 40Ωm to 450Ωm with thickness ranging from 1.25 to 7.5 m. The weathered basement has resistivity values ranging from 50Ωm to 593Ωm and thickness between 1.37 and 20.1 m. The fractured basement has resistivity values ranging from 218Ωm to 520Ωm and thickness of between 12.9 and 26.3 m. The fresh basement (bedrock) has resistivity values ranging from 1215Ωm to 2150Ωm with infinite depth. However, the depth of the earth’s surface to the bedrock surface varies between 2.63 and 34.99 m. The study further stressed the importance of the findings in civil engineering structures and groundwater prospecting.Keywords: electrical resistivity, CERT (CT), vertical electrical sounding (VES), top soil (TP), weathered basement (WB), partly weathered basement (PWB), fresh basement (FB)
Procedia PDF Downloads 3338818 Soil Enzyme Activity as Influenced by Post-emergence Herbicides Applied in Soybean [Glycine max (L.) Merrill]
Authors: Uditi Dhakad, Baldev Ram, Chaman K. Jadon, R. K. Yadav, D. L. Yadav, Pratap Singh, Shalini Meena
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A field experiment was conducted during Kharif 2021 at Agricultural Research Station, Kota, to evaluate the effect of different post-emergence herbicides applied to soybean [Glycine max (L.) Merrill] on soil enzymes activity viz. dehydrogenase, phosphatase, and urease. The soil of the experimental site was clay loam (vertisols) in texture and slightly alkaline in reaction with 7.7 pH. The soil was low in organic carbon (0.49%), medium in available nitrogen (210 kg/ha), phosphorus (23.5 P2O5 kg/ha), and high in potassium (400 K2O kg/ha) status. The results elucidated that no significant adverse effect on soil dehydrogenase, urease, and phosphatase activity was determined with the application of post-emergence herbicides over the untreated control. Two hands weeding at 20 and 40 DAS registered maximum dehydrogenase enzyme activity (0.329 μgTPF/g soil/d) closely followed by herbicides mixtures and sole herbicide while pre-emergence application of pendimethalin + imazethapyr 960 g a.i./ha and pendimethalin 1.0 kg a.i./ha significantly reduced dehydrogenase enzyme activity compared to control. Urease enzyme activity was not much affected under different weed control treatments and weedy checks. The treatments were found statistically non-significant, and values ranged between 1.16-1.25 μgNH4N/g soil/d. Phosphatase enzyme activity was also not influenced significantly due to various weed control treatments. Though maximum phosphatase enzyme activity (30.17 μgpnp/g soil/hr) was observed under two-hand weeding, followed by fomesafen + fluazifop-p-butyl 220 g a.i./ha. Herbicidal weed control measures did not influence the total bacteria, fungi, and actinomycetes population.Keywords: dehydrogenase, phosphatase, post-emergence, soil enzymes, urease.
Procedia PDF Downloads 1098817 Liquefaction Assessment of Marine Soil in Western Yemen Region Based on Laboratory and Field Tests
Authors: Monalisha Nayak, T. G. Sitharam
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Liquefaction is a major threat for sites consists of or on sandy soil. But this present study concentrates on the behavior of fine soil under cyclic loading. This paper presents the study of liquefaction susceptibility of marine silty clay to clayey silt for an offshore site near western Yemen. The submerged and loose sediment condition of marine soil of an offshore site can favour liquefaction during earthquakes. In this regard, the liquefaction susceptibility of the site was carried out based on both field test results and laboratory test results. From field test results of seismic cone penetration test (SCPT), liquefaction susceptibility was assessed considering normalized cone tip resistance, and normalized friction ratio and results give an idea regarding both cyclic mobility and flow liquefaction. Laboratory cyclic triaxial tests were also conducted on saturated undisturbed and remoulded sample to study the effect of cyclic loading on strength and strain characteristics. Liquefaction susceptibility of the marine soft soil was also carried out based on index properties like grain size distribution, natural moisture content and liquid limit of soil.Keywords: index properties, liquefaction, marine soil, seismic cone penetration test (SCPT)
Procedia PDF Downloads 2388816 Evaluating the Topsoil and Subsoil Physical Quality Using Relative Bulk Density in Urmia Plain
Authors: Hossein Asgarzadeh, Ayoub Osmani, Farrokh Asadzadeh, Mohammad Reza Mosaddeghi
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This study was conducted to evaluate the topsoil and subsoil physical quality using relative bulk density (RBD) in Urmia plain in Iran. Undisturbed samples were collected from two layers (topsoil and subsoil) of thirty agricultural soils. Categories of 0.72 ≥ RBD (low degree of compactness), 0.82 > RBD > 0.72 (moderate/optimum degree of compactness), and RBD ≥ 0.82 (high degree of compactness) were used to evaluate soil physical quality (SPQ). Two topsoils had a low degree of compactness, fourteen topsoils had an optimum degree of compactness, and the rest (i.e., fourteen topsoils) had a high degree of compactness. Only one subsoil had an optimum degree of compactness, and twenty-eight subsoils (i.e., 93%) had a high degree of compactness, indicating poor SPQ of the subsoil layer in the studied region. It seems that conventional tillage in the past decades destroyed the pore system in the majority of studied subsoils. The high degree of compactness would reduce soil aeration and increase soil penetration resistance which could restrict root and plant growth. Conversely, a low degree of soil compactness is expected to reduce the root-soil contact.Keywords: compactness, relative bulk density, soil physical quality
Procedia PDF Downloads 1278815 Reliability Analysis of Soil Liquefaction Based on Standard Penetration: A Case Study in Babol City
Authors: Mehran Naghizaderokni, Asscar Janalizadechobbasty
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There are more probabilistic and deterministic liquefaction evaluation procedures in order to judge whether liquefaction will occur or not. A review of this approach reveals that there is a need for a comprehensive procedure that accounts for different sources of uncertainty in liquefaction evaluation. In fact, for the same set of input parameters, different methods provide different factors of safety and/or probabilities of liquefaction. To account for the different uncertainties, including both the model and measurement uncertainties, reliability analysis is necessary. This paper has obtained information from Standard Penetration Test (SPT) and some empirical approaches such as: Seed et al, Highway bridge of Japan approach to soil liquefaction, The Overseas Coastal Area Development Institute of Japan (OCDI) and reliability method to studying potential of liquefaction in soil of Babol city in the north of Iran are compared. Evaluation potential of liquefaction in soil of Babol city is an important issue since the soil of some area contains sand, seismic area, increasing level of underground waters and consequently saturation of soil; therefore, one of the most important goals of this paper is to gain suitable recognition of liquefaction potential and find the most appropriate procedure of evaluation liquefaction potential to decrease related damages.Keywords: reliability analysis, liquefaction, Babol, civil, construction and geological engineering
Procedia PDF Downloads 5048814 Development of Corn (Zea mays L.) Stalk Geotextile Net for Soil Erosion Mitigation
Authors: Cristina S. Decano, Vitaliana U. Malamug, Melissa E. Agulto, Helen F. Gavino
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This study aimed to introduce new natural fiber to be used in the production of geotextile net for mitigation of soil erosion. Fiber extraction from the stalks was the main challenge faced during the processing of stalks to ropes. Thus, an investigation on the extraction procedures of corn (Zea mays L.) stalk under biological and chemical retting was undertaken. Results indicated significant differences among percent fiber yield as affected by the retting methods used with values of 15.07%, 12.97%, 11.60%, and 9.01%, for dew, water, chemical (1 day after harvest and15 days after harvest), respectively, with the corresponding average extracting duration of 70, 82, 89, and 94 minutes. Physical characterization of the developed corn stalk geotextile net resulted to average mass per unit area of 806.25 g/m2 and 241% water absorbing capacity. The effect of corn stalk geotextile net in mitigating soil erosion was evaluated in a laboratory experiment for 30o and 60o inclinations with three treatments: bare soil (A1), corn stalk geotextile net (A2) and combined cornstalk geotextile net and vegetation cover (A3). Results revealed that treatment A2 and A3 significantly decreased sediment yield and an increase in terms of soil loss reduction efficiency. The cost of corn stalk geotextile net is Php 62.41 per square meter.Keywords: corn stalk, natural geotextile, retting, soil erosion
Procedia PDF Downloads 3028813 Soil Remediation Technologies towards Green Remediation Strategies
Authors: G. Petruzzelli, F. Pedron, M. Grifoni, M. Barbafieri, I. Rosellini, B. Pezzarossa
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As a result of diverse industrial activities, pollution from numerous contaminant affects both groundwater and soils. Many contaminated sites have been discovered in industrialized countries and their remediation is a priority in environmental legislations. The aim of this paper is to provide the evolution of remediation from consolidated invasive technologies to environmental friendly green strategies. Many clean-up technologies have been used. Nowadays the technologies selection is no longer exclusively based on eliminating the source of pollution, but the aim of remediation includes also the recovery of soil quality. “Green remediation”, a strategy based on “soft technologies”, appears the key to tackle the issue of remediation of contaminated sites with the greatest attention to environmental quality, including the preservation of soil functionality.Keywords: bioremediation, Green Remediation, phytoremediation, remediation technologies, soil
Procedia PDF Downloads 2338812 Durability of Lime Treated Soil Reinforced by Natural Fibre under Bending Force
Authors: Vivi Anggraini, Afshin Asadi, Bujang B. K. Huat
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Earth structures constructed of marine clay soils have tendency to crack. In order to improve the flexural strength and brittleness, a technique of mixing short fibers is introduced to the soil lime mixture. Coir fiber was used in this study as reinforcing elements. An experimental investigation consisting primarily of flexural tensile tests was conducted to examine the influence of coir fibers on the flexural behaviour of the reinforced soils. The test results demonstrated that the coir fibers were effective in improving the flexural strength and young’s modulus of all soils were examined and ductility after peak strength for reinforced marine clay soil was treated by lime. 5% lime treated soil and 1% coir fiber reinforced soil specimen’s demonstrated good strength and durability when submerged in water and retained 45% of their air-cured strengths.Keywords: flexural strength, durabilty, lime, coir fibers, bending force, ductility
Procedia PDF Downloads 4718811 Thermal, Chemical, and Mineralogical Properties of Soil Building Blocks Reinforced with Cement
Authors: Abdelmalek Ammari
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This paper represents an experimental study to determine the effect between thermal conductivity of Compressed Earth Block Stabilized (CEBs) by cement and the mineralogical and chemical analyses of soil, all the samples of CEB in the dry state and with different content of cement, the samples made by soil stabilized by Portland Cement. The soil used collected from fez city in Morocco. That determination of the thermal conductivity of CEBs plays an important role when considering its suitability for energy saving insulation. The measurement technique used to determine thermal conductivity is called hot ring method, the thermal conductivity of the tested samples is strongly affected by the quantity of the cement added. The soil of Fez, mainly composed of calcite, quartz, and dolomite, improved the behaviour of the material by the addition of cement. The findings suggest that to manufacture lightweight samples with high thermal insulation properties, it is advisable to use clays that contain quartz. . In addition, quartz has high thermal conductivity.Keywords: compressed earth blocks, thermal conductivity, mineralogical, chemical, temperature
Procedia PDF Downloads 1588810 Biodegradation Study of a Biocomposite Material Based on Sunflower Oil and Alfa Fibers as Natural Resources
Authors: Sihem Kadem, Ratiba Irinislimane, Naima Belhaneche
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The natural resistance to biodegradation of polymeric materials prepared from petroleum-based source and the management of their wastes in the environment are the driving forces to replace them by other biodegradable materials from renewable resources. For that, in this work new biocomposites materials have been synthesis from sunflower oil (Helianthus annuus) and alfa plants (Stipatenacissima) as natural based resources. The sunflower oil (SFO) was chemically modified via epoxidation then acrylation reactions to obtain acrylated epoxidized sunflower oil resin (AESFO). The AESFO resin was then copolymerized with styrene as co-monomer in the presence of boron trifluoride (BF3) as cationic initiator and cobalt octoate (Co) as catalyst. The alfa fibers were treated with alkali treatment (5% NaOH) before been used as bio-reinforcement. Biocomposites were prepared by mixing the resin with untreated and treated alfa fibers at different percentages. A biodegradation study was carried out for the synthesized biocomposites in a solid medium (burial in the soil) by evaluated, first, the loss of mass, the results obtained were reached between 7.8% and 11% during one year. Then an observation under an optical microscope was carried out, after one year of burial in the soil, microcracks, brown and black spots were appeared on the samples surface. This results shows that the synthesized biocomposites have a great aptitude for biodegradation.Keywords: alfa fiber, biocomposite, biodegradation, soil, sunflower oil
Procedia PDF Downloads 1668809 Finite Element Modeling of Integral Abutment Bridge for Lateral Displacement
Authors: M. Naji, A. R. Khalim, M. Naji
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Integral Abutment Bridges (IAB) are defined as simple or multiple span bridges in which the bridge deck is cast monolithically with the abutment walls. This kind of bridges are becoming very popular due to different aspects such as good response under seismic loading, low initial costs, elimination of bearings and less maintenance. However, the main issue related to the analysis of this type of structures is dealing with soil-structure interaction of the abutment walls and the supporting piles. A two-dimensional, non-linear finite element (FE) model of an integral abutment bridge has been developed to study the effect of lateral time history displacement loading on the soil system.Keywords: integral abutment bridge, soil structure interaction, finite element modeling, soil-pile interaction
Procedia PDF Downloads 2938808 Determining G-γ Degradation Curve in Cohesive Soils by Dilatometer and in situ Seismic Tests
Authors: Ivandic Kreso, Spiranec Miljenko, Kavur Boris, Strelec Stjepan
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This article discusses the possibility of using dilatometer tests (DMT) together with in situ seismic tests (MASW) in order to get the shape of G-g degradation curve in cohesive soils (clay, silty clay, silt, clayey silt and sandy silt). MASW test provides the small soil stiffness (Go from vs) at very small strains and DMT provides the stiffness of the soil at ‘work strains’ (MDMT). At different test locations, dilatometer shear stiffness of the soil has been determined by the theory of elasticity. Dilatometer shear stiffness has been compared with the theoretical G-g degradation curve in order to determine the typical range of shear deformation for different types of cohesive soil. The analysis also includes factors that influence the shape of the degradation curve (G-g) and dilatometer modulus (MDMT), such as the overconsolidation ratio (OCR), plasticity index (IP) and the vertical effective stress in the soil (svo'). Parametric study in this article defines the range of shear strain gDMT and GDMT/Go relation depending on the classification of a cohesive soil (clay, silty clay, clayey silt, silt and sandy silt), function of density (loose, medium dense and dense) and the stiffness of the soil (soft, medium hard and hard). The article illustrates the potential of using MASW and DMT to obtain G-g degradation curve in cohesive soils.Keywords: dilatometer testing, MASW testing, shear wave, soil stiffness, stiffness reduction, shear strain
Procedia PDF Downloads 3218807 Phytoremediation Potential of Hibiscus Cannabinus L. Grown on Different Soil Cadmium Concentration
Authors: Sarra Arbaoui, Taoufik Bettaieb
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Contaminated soils and problems related to them have increasingly become a matter of concern. The most common the contaminants generated by industrial urban emissions and agricultural practices are trace metals). Remediation of trace metals which pollute soils can be carried out using physico-chemical processes. Nevertheless, these techniques damage the soil’s biological activity and require expensive equipment. Phytoremediation is a relatively low-cost technology based on the use of selected plants to remove, degrades or contains pollutants. The potential of kenaf for phytoremediation on Cd-contaminated soil was investigated. kenaf plants have been grown in pots containing different concentrations of cadmium. The observations made were for biomass production and cadmium content in different organs determinate by atomic emission spectrometry. Cadmium transfer from a contaminated soil to plants and into plant tissues are discussed in terms of the Bioconcentration Factor (BCF) and the Transfer Factor (TF). Results showed that Cd was found in kenaf plants at different levels. Tolerance and accumulation potential and biomass productivity indicated that kenaf could be used in phytoremediation.Keywords: kenaf, cadmium, phytoremediation, contaminated soil
Procedia PDF Downloads 5298806 Effect of Thinning Practice on Carbon Storage in Soil Forest Northern Tunisia
Authors: Zouhaier Nasr, Mohamed Nouri
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The increase in greenhouse gases since the pre-industrial period is a real threat to disrupting the balance of marine and terrestrial ecosystems. Along with the oceans, forest soils are considered to be the planet's second-largest carbon sink. North African forests have been subject to alarming degradation for several decades. The objective of this investigation is to determine and quantify the effect of thinning practiced in pine forests in northern Tunisia on the storage of organic carbon in the trees and in the soil. The plot planted in 1989 underwent thinning in 2005 on to plots; the density is therefore 1600 trees/ha in control and 400 trees/ha in thinning. Direct dendrometric measurements (diameter, height, branches, stem) were taken. In the soil part, six profiles of 1m / 1m / 1m were used for soil and root samples and biomass and organic matter measurements. The measurements obtained were statistically processed by appropriate software. The results clearly indicate that thinning improves tree growth, so the diameter increased from 24.3 cm to 30.1 cm. Carbon storage in the trunks was 35% more and 25% for the whole tree. At ground level, the thinned plot shows a slight increase in soil organic matter and quantity of carbon per tree, exceeding the control by 10 to 25%.Keywords: forest, soil, carbon, climate change, Tunisia
Procedia PDF Downloads 1358805 Surface Coatings of Boards Made from Alternative Materials
Authors: Stepan Hysek, Petra Gajdacova
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In recent years, alternative materials, such as annual plants or recycled and waste materials are becoming more and more popular input material for the production of composite materials. They can be used for the production of insulation boards, construction boards or furniture boards. Surface finishing of those boards is essential for utilization in furniture. However, some difficulties could occur during coating of boards from alternative materials; physical and chemical differences from conventional particleboards need to be considered. From the physical aspects, surface soundness and surface roughness mainly determine the quality of the surface. Since surface layers of boards from alternative materials have often lower density, these characteristics could be deteriorated and thus the production process needs to be optimized. Also, chemical reactions of board’s material with coating could be undesirable. The objective of this study is to evaluate the parameters affecting the surface quality of boards made form alternative materials and to find possibilities of the coating of these boards. In this study, boards of particles from rapeseed stems were produced using a laboratory press. Surface soundness, as representatives of mechanical properties and surface roughness, as representative of physical properties, were measured on boards from rapeseed stems. Results clearly indicated that produced boards had lower surface quality than commercially produced particle boards from wood. Therefore, higher thickness of surface coating on rapeseed based boards is needed.Keywords: coating, surface, annual plant, composites, particleboard
Procedia PDF Downloads 2788804 The Friction of Oil Contaminated Granular Soils; Experimental Study
Authors: Miron A., Tadmor R., Pinkert S.
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Soil contamination is a pressing environmental concern, drawing considerable focus due to its adverse ecological and health outcomes, and the frequent occurrence of contamination incidents in recent years. The interaction between the oil pollutant and the host soil can alter the mechanical properties of the soil in a manner that can crucially affect engineering challenges associated with the stability of soil systems. The geotechnical investigation of contaminated soils has gained momentum since the Gulf War in the 1990s, when a massive amount of oil was spilled into the ocean. Over recent years, various types of soil contaminations have been studied to understand the impact of pollution type, uncovering the mechanical complexity that arises not just from the pollutant type but also from the properties of the host soil and the interplay between them. This complexity is associated with diametrically opposite effects in different soil types. For instance, while certain oils may enhance the frictional properties of cohesive soils, they can reduce the friction in granular soils. This striking difference can be attributed to the different mechanisms at play: physico-chemical interactions predominate in the former case, whereas lubrication effects are more significant in the latter. this study introduces an empirical law designed to quantify the mechanical effect of oil contamination in granular soils, factoring the properties of both the contaminating oil and the host soil. This law is achieved by comprehensive experimental research that spans a wide array of oil types and soils with unique configurations and morphologies. By integrating these diverse data points, our law facilitates accurate predictions of how oil contamination modifies the frictional characteristics of general granular soils.Keywords: contaminated soils, lubrication, friction, granular media
Procedia PDF Downloads 598803 The Effectiveness of Spatial Planning And Land Use Management Act, 2013 in Fetakgomo Tubatse Local Municipality: Case Study of Apel Nodal Point
Authors: Hlabishi Peter Ntloana
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This paper aims to present the effectiveness of the Spatial Planning and Land Use Management Act, 2013, in addressing key spatial challenges in Fetakgomo Tubatse Local Municipality, mainly focusing on Apel nodal point. Spatial Planning and Land Use Management Act, 2013, popularly known as SPLUMA, aimed at addressing emerging and existing spatial planning and land use management challenges in South Africa. There are critical key spatial challenges that are continuously encountered in Apel Nodal Point, which include dispersed rural settlement mainly in a communal settlement. The spatial patterns and rural settlements development patterns are a challenge, and such results in uncoordinated human settlements. The objective of this research paper is to analyze the spatial planning of Apel nodal points and determine the effectiveness of the SPLUMA policy. Key Informant interviews were conducted with 20 participants, and also the municipal Spatial Development Framework was considered to explore more challenges and proposed recommendations. The results divulged that there is a huge gap in addressing spatial planning, mainly in rural areas, and correlation with the findings of the Municipal Spatial Development framework. In conclusion, spatial planning remains a critical dilemma in most rural settlements, and there must be programmes and strategies to balance the effectiveness of spatial planning in urban and rural settlements.Keywords: land use management, rural settlement, spatial development framework, spatial planning
Procedia PDF Downloads 1818802 In situ Immobilization of Mercury in a Contaminated Calcareous Soil Using Water Treatment Residual Nanoparticles
Authors: Elsayed A. Elkhatib, Ahmed M. Mahdy, Mohamed L. Moharem, Mohamed O. Mesalem
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Mercury (Hg) is one of the most toxic and bio-accumulative heavy metal in the environment. However, cheap and effective in situ remediation technology is lacking. In this study, the effects of water treatment residuals nanoparticles (nWTR) on mobility, fractionation and speciation of mercury in an arid zone soil from Egypt were evaluated. Water treatment residual nanoparticles with high surface area (129 m 2 g-1) were prepared using Fritsch planetary mono mill. Scanning and transmission electron microscopy revealed that the nanoparticles of WTR nanoparticles are spherical in shape, and single particle sizes are in the range of 45 to 96 nm. The x-ray diffraction (XRD) results ascertained that amorphous iron, aluminum (hydr)oxides and silicon oxide dominating all nWTR, with no apparent crystalline iron–Al (hydr)oxides. Addition of nWTR, greatly increased the Hg sorption capacities of studied soils and greatly reduced the cumulative Hg released from the soils. Application of nWTR at 0.10 and 0.30 % rates reduced the released Hg from the soil by 50 and 85 % respectively. The power function and first order kinetics models well described the desorption process from soils and nWTR amended soils as evidenced by high coefficient of determination (R2) and low SE values. Application of nWTR greatly increased the association of Hg with the residual fraction. Meanwhile, application of nWTR at a rate of 0.3% greatly increased the association of Hg with the residual fraction (>93%) and significantly increased the most stable Hg species (Hg(OH)2 amor) which in turn enhanced Hg immobilization in the studied soils. Fourier transmission infrared spectroscopy analysis indicated the involvement of nWTR in the retention of Hg (II) through OH groups which suggest inner-sphere adsorption of Hg ions to surface functional groups on nWTR. These results demonstrated the feasibility of using a low-cost nWTR as best management practice to immobilize excess Hg in contaminated soils.Keywords: release kinetics, Fourier transmission infrared spectroscopy, Hg fractionation, Hg species
Procedia PDF Downloads 2388801 Comparative Study of the Earth Land Surface Temperature Signatures over Ota, South-West Nigeria
Authors: Moses E. Emetere, M. L. Akinyemi
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Agricultural activities in the South–West Nigeria are mitigated by the global increase in temperature. The unpredictive surface temperature of the area had increased health challenges amongst other social influence. The satellite data of surface temperatures were compared with the ground station Davis weather station. The differential heating of the lower atmosphere were represented mathematically. A numerical predictive model was propounded to forecast future surface temperature.Keywords: numerical predictive model, surface temperature, satellite date, ground data
Procedia PDF Downloads 4768800 Voltage Polarity in Electrospinning: Way to Control Surface Properties of Polymer Fibers
Authors: Urszula Stachewicz
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Surface properties of materials are the key parameter in many applications, especially in the biomedical field, to control cell-material interactions. In our work, we want to achieve the controllability of surface properties of polymer fibers via a single-step electrospinning process by alternating voltage polarities. Voltage polarity defines the charge accumulated on the surface of the liquid jet and the surface of the fibers. Positive polarity attracts negatively charged groups to fibers’ surface, whereas negative polarity moves the negatively charged functional groups away from the surface. This way, we can control the surface chemistry, wettability, and additionally surface potential of electrospun fibers. Within our research, we characterized surface chemistry using X-ray photoelectron microscopy (XPS) and surface potential with Kelvin probe force microscopy (KPFM) on electrospun fibers of commonly used polymers such as PCL, PVDF, and PMMA, often used as biomaterials. We proved the significant effect of fibers' surface potential on cell integration with the scaffolds and further cells development for the regeneration processes based on the osteoblast and fibroblast culture studies. Acknowledgments: The study was conducted within ‘Nanofiber-based sponges for atopic skin treatment’ project, which is carried out within the First TEAM programme of the Foundation for Polish Science co-financed by the European Union under the European Regional Development Fund, project no POIR.04.04.00-00- 4571/18-00.Keywords: cell attachment, fibers, fibroblasts, osteoblast, proliferation, surface potential
Procedia PDF Downloads 1218799 Effect of Bamboo Chips in Cemented Sand Soil on Permeability and Mechanical Properties in Triaxial Compression
Authors: Sito Ismanti, Noriyuki Yasufuku
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Cement utilization to improve the properties of soil is a well-known method applied in field. However, its addition in large quantity must be controlled. This study presents utilization of natural and environmental-friendly material mixed with small amount of cement content in soil improvement, i.e. bamboo chips. Absorbability, elongation, and flatness ratio of bamboo chips were examined to investigate and understand the influence of its characteristics in the mixture. Improvement of dilation behavior as a problem of loose and poorly graded sand soil is discussed. Bamboo chips are able to improve the permeability value that affects the dilation behavior of cemented sand soil. It is proved by the stress path as the result of triaxial compression test in the undrained condition. The effect of size and content variation of bamboo chips, as well as the curing time variation are presented and discussed.Keywords: bamboo chips, permeability, mechanical properties, triaxial compression
Procedia PDF Downloads 3378798 Agriculture Yield Prediction Using Predictive Analytic Techniques
Authors: Nagini Sabbineni, Rajini T. V. Kanth, B. V. Kiranmayee
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India’s economy primarily depends on agriculture yield growth and their allied agro industry products. The agriculture yield prediction is the toughest task for agricultural departments across the globe. The agriculture yield depends on various factors. Particularly countries like India, majority of agriculture growth depends on rain water, which is highly unpredictable. Agriculture growth depends on different parameters, namely Water, Nitrogen, Weather, Soil characteristics, Crop rotation, Soil moisture, Surface temperature and Rain water etc. In our paper, lot of Explorative Data Analysis is done and various predictive models were designed. Further various regression models like Linear, Multiple Linear, Non-linear models are tested for the effective prediction or the forecast of the agriculture yield for various crops in Andhra Pradesh and Telangana states.Keywords: agriculture yield growth, agriculture yield prediction, explorative data analysis, predictive models, regression models
Procedia PDF Downloads 3218797 Value for Money in Investment Projects
Authors: Jan Ceselsky
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Construction and reconstruction of settlements and individual municipalities, environmental management and the creation, deployment of the forces of production and building transport and technical equipment requires a large expenditure of material and human resources. That is why the economic aspects of the majority decision in these planes built in the foreground and are often decisive. Thereby but more serious is that the economic aspects of the settlement, the creation and function remain in their whole, unprocessed, and can not speak of a set of individual techniques and methods traditional indicators and experiments with new approaches. This is true both at the level of the national economy, and in their own urban designs. Still a few remain identified specific economic shaping patterns of settlement and the less it is possible to speak of their control. Also practical assessing economics of specific solutions are often used non-apt indicators in addition to economics usually identifies with the lowest acquisition cost or high-intensity land use with little regard for functional efficiency and little studied much higher operating and maintenance costs.Keywords: investment, municipal engineering, value for money, construction
Procedia PDF Downloads 2988796 Institutionalizing Peace in Iraqi Kurdistan Post-civil War, 1998 to Present
Authors: Hawre Hasan Hama, Choman Mahmood H. Rashid
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The four-year armed conflict between the Kurdistan Democratic Party (KDP) and the Patriotic Union of Kurdistan (PUK) ended in September 1998 under the terms of the Washington Agreement. Since then, there has been a quarter-century of durable peace between the two combatant parties, though they have often been at odds politically. Based on interviews with Kurdish political leaders from both parties, this paper argues that sharing or dividing power across all four dimensions of state power — political, military, territorial, and economic — has played a vital role ensuring the durability of the peace settlement. The paper traces the KDP-PUK power sharing system through three stages: the transition stage (1998-2006), the “golden” period (2006-2013), the “weakening” period (2013 to present).Keywords: peace settlement, enduring peace, power-sharing and power dividing, Iraqi Kurdistan.
Procedia PDF Downloads 968795 Design and Optimization of Soil Nailing Construction
Authors: Fereshteh Akbari, Farrokh Jalali Mosalam, Ali Hedayatifar, Amirreza Aminjavaheri
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The soil nailing is an effective method to stabilize slopes and retaining structures. Consequently, the lateral and vertical displacement of retaining walls are important criteria to evaluate the safety risks of adjacent structures. This paper is devoted to the optimization problems of retaining walls based on ABAQOUS Software. The various parameters such as nail length, orientation, arrangement, horizontal spacing, and bond skin friction, on lateral and vertical displacement of retaining walls are investigated. In order to ensure accuracy, the mobilized shear stress acting around the perimeter of the nail-soil interface is also modeled in ABAQOUS software. The observed trend of results is compared to the previous researches.Keywords: retaining walls, soil nailing, ABAQOUS software, lateral displacement, vertical displacement
Procedia PDF Downloads 1378794 Surface Roughness Effects in Pure Sliding EHL Line Contacts with Carreau-Type Shear-Thinning Lubricants
Authors: Punit Kumar, Niraj Kumar
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The influence of transverse surface roughness on EHL characteristics has been investigated numerically using an extensive set of full EHL line contact simulations for shear-thinning lubricants under pure sliding condition. The shear-thinning behavior of lubricant is modeled using Carreau viscosity equation along with Doolittle-Tait equation for lubricant compressibility. The surface roughness is assumed to be sinusoidal and it is present on the stationary surface. It is found that surface roughness causes sharp pressure peaks along with reduction in central and minimum film thickness. With increasing amplitude of surface roughness, the minimum film thickness decreases much more rapidly as compared to the central film thickness.Keywords: EHL, Carreau, shear-thinning, surface roughness, amplitude, wavelength
Procedia PDF Downloads 7348793 Development of In Situ Permeability Test Using Constant Discharge Method for Sandy Soils
Authors: A. Rifa’i, Y. Takeshita, M. Komatsu
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The post-rain puddles problem that occurs in the first yard of Prambanan Temple are often disturbing visitor activity. A poodle layer and a drainage system has ever built to avoid such a problem, but puddles still didn’t stop appearing after rain. Permeability parameter needs to be determined by using more simple procedure to find exact method of solution. The instrument modelling were proposed according to the development of field permeability testing instrument. This experiment used proposed Constant Discharge method. Constant Discharge method used a tube poured with constant water flow. The procedure were carried out from unsaturated until saturated soil condition. Volumetric water content (θ) were being monitored by soil moisture measurement device. The results were relationship between k and θ which drawn by numerical approach Van Genutchen model. Parameters θr optimum value obtained from the test was at very dry soil. Coefficient of permeability with a density of 19.8 kN/m3 for unsaturated conditions was in range of 3 x 10-6 cm/sec (Sr= 68 %) until 9.98 x 10-4 cm/sec (Sr= 82 %). The equipment and testing procedure developed in this research was quite effective, simple and easy to be implemented on determining field soil permeability coefficient value of sandy soil. Using constant discharge method in proposed permeability test, value of permeability coefficient under unsaturated condition can be obtained without establish soil water characteristic curve.Keywords: constant discharge method, in situ permeability test, sandy soil, unsaturated conditions
Procedia PDF Downloads 3898792 Mechanical Activation of a Waste Material Used as Cement Replacement in Soft Soil Stabilisation
Authors: Hassnen M. Jafer, W. Atherton, F. Ruddock, E. Loffil
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Waste materials or sometimes called by-product materials have been increasingly used as construction material to reduce the usage of cement in different construction projects. In the field of soil stabilisation, waste materials such as pulverised fuel ash (PFA), biomass fly ash (BFA), sewage sludge ash (SSA), etc., have been used since 1960s in last century. In this study, a particular type of a waste material (WM) was used in soft soil stabilisation as a cement replacement, as well as, the effect of mechanical activation, using grinding, on the performance of this WM was also investigated. The WM used in this study is a by-product resulted from the incineration processes between 1000 and 1200oc in domestic power generation plant using a fluidized bed combustion system. The stabilised soil in this study was an intermediate plasticity silty clayey soil with medium organic matter content. The experimental works were conducted first to find the optimum content of WM by carrying out Atterberg limits and unconfined compressive strength (UCS) tests on soil samples contained (0, 3, 6, 9, 12, and 15%) of WM by the dry weight of soil. The UCS test was carried out on specimens provided to different curing periods (zero, 7, 14, and 28 days). Moreover, the optimum percentage of the WM was subject to different periods of grinding (10, 20, 30, 40mins) using mortar and pestle grinder to find the effect of grinding and its optimum time by conducting UCS test. The results indicated that the WM used in this study improved the physical properties of the soft soil where the index of plasticity (IP) was decreased significantly from 21 to 13.10 with 15% of WM. Meanwhile, the results of UCS test indicated that 12% of WM was the optimum and this percentage developed the UCS value from 202kPa to 700kPa for 28 days cured samples. Along with the time of grinding, the results revealed that 10 minutes of grinding was the best for mechanical activation for the WM used in this study.Keywords: soft soil stabilisation, waste materials, grinding, and unconfined compressive strength
Procedia PDF Downloads 2818791 Inversion of PROSPECT+SAIL Model for Estimating Vegetation Parameters from Hyperspectral Measurements with Application to Drought-Induced Impacts Detection
Authors: Bagher Bayat, Wouter Verhoef, Behnaz Arabi, Christiaan Van der Tol
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The aim of this study was to follow the canopy reflectance patterns in response to soil water deficit and to detect trends of changes in biophysical and biochemical parameters of grass (Poa pratensis species). We used visual interpretation, imaging spectroscopy and radiative transfer model inversion to monitor the gradual manifestation of water stress effects in a laboratory setting. Plots of 21 cm x 14.5 cm surface area with Poa pratensis plants that formed a closed canopy were subjected to water stress for 50 days. In a regular weekly schedule, canopy reflectance was measured. In addition, Leaf Area Index (LAI), Chlorophyll (a+b) content (Cab) and Leaf Water Content (Cw) were measured at regular time intervals. The 1-D bidirectional canopy reflectance model SAIL, coupled with the leaf optical properties model PROSPECT, was inverted using hyperspectral measurements by means of an iterative optimization method to retrieve vegetation biophysical and biochemical parameters. The relationships between retrieved LAI, Cab, Cw, and Cs (Senescent material) with soil moisture content were established in two separated groups; stress and non-stressed. To differentiate the water stress condition from the non-stressed condition, a threshold was defined that was based on the laboratory produced Soil Water Characteristic (SWC) curve. All parameters retrieved by model inversion using canopy spectral data showed good correlation with soil water content in the water stress condition. These parameters co-varied with soil moisture content under the stress condition (Chl: R2= 0.91, Cw: R2= 0.97, Cs: R2= 0.88 and LAI: R2=0.48) at the canopy level. To validate the results, the relationship between vegetation parameters that were measured in the laboratory and soil moisture content was established. The results were totally in agreement with the modeling outputs and confirmed the results produced by radiative transfer model inversion and spectroscopy. Since water stress changes all parts of the spectrum, we concluded that analysis of the reflectance spectrum in the VIS-NIR-MIR region is a promising tool for monitoring water stress impacts on vegetation.Keywords: hyperspectral remote sensing, model inversion, vegetation responses, water stress
Procedia PDF Downloads 226