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1
Thevanayagam, S., T. Shenthan, S. Mohan e J. Liang. "Undrained Fragility of Clean Sands, Silty Sands, and Sandy Silts". Journal of Geotechnical and Geoenvironmental Engineering 128, n. 10 (ottobre 2002): 849–59. http://dx.doi.org/10.1061/(asce)1090-0241(2002)128:10(849).
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Kryvulchenko, Anatolii. "Oleshkivski Sands as a hierarchically built natural system". Visnyk of the Lviv University. Series Geography 53 (18 dicembre 2019): 197–209. http://dx.doi.org/10.30970/vgg.2019.53.10666.
Testo completoAbstract (sommario):
Оleshkivski Sands (Oleshia) are one of the morphosculptures on the Left bank of the lower part of Dnipro river, which is formed on alluvial and periglacial deposits. The article clearly identifies the location of these sands among other morphosculptures of the Left bank of the lower part of Dnipro. In view of the ambiguity, two regions of the Left Bank are considered separately – nearby arenian sandy-loamy geocomplexes with the presence of extremely specific sandy hilly-depressions geocomplexes and the territory of the hilly-lowland plain (Kardashynka lowland), which is located between the Dnipro delta and sands massives of the Kelegei arena. Oleshia consists of seven hilly-sanded arenas and six inter-arenial sanded flat plains. Accordingly, the area of Оleshkivski Sands is 219.9 thousand hectares, almost 80 % of which are sanded arenas. Arenas are represented here as hilly sandy plains and depressions. These sandy plains divided by sand types such as hilly (hillock, hillock-dune and hilly), hilly-ridge and flat-wavy, depressions – by flat-wavy, ridge-hollow, wavy-shallow depressions and ridge-shallow depressions. Such types of relief forms are represented by the following microforms of aeolian genesis: hillocks, hills, parabolic dunes, aeolian fields, deflation depressions and also by microforms of fluvial genesis: hilly-ridges, depressions among hilly sandy massifs, gally (redundans), inter-ridge depressions (inter-ridge hollows). On the surface of sandy massifs, especially in places where the sands are exposed, relief nanoforms are formed, which are represented by small riffles, nabkhas, blowing furrows, tafonies and also by aeolian trains, cut-off lobes, cliffs, cornices. This system of forms of relief of the Oleshkivski Sands testifies to the complex and various processes of their formation, but special attention should be paid at sand ridges, especially those with the parallel ridge-hollow spatial organization. They, for example, in the south of the Kinburn arena became the basis for the formation of the aeolian-hydrogen landscape that is unique for the territory of Ukraine. The author associates the creation of the Oleshіa ridge-hollow geocomplexes with the probable catastrophic floods (floodstreams). It is advisable to consider these ridges as a manifestation of giant ripples (diluvial dunes), which are often covered by deposits with different nature of formation. This is evidenced by the variety of typology of relief forms on the territory of the Oleshkivski arenas. Thalassogenic, suffusion-subsidence and anthropogenic factors also deserve special attention in characterizing of shaping the relief of the region. Key words: the Left bank of the Lower Dnipro, Оleshkivski Sands, hierarchy of relief forms, sandy arena, aeolian processes, fluvial forms.
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Dulepova, N. A., e A. Yu Korolyuk. "Psammophyte vegetation of the Selenga river basin (Republic of Buryatia)". Vegetation of Russia, n. 27 (2015): 78–95. http://dx.doi.org/10.31111/vegrus/2015.27.78.
Testo completoAbstract (sommario):
Modern aeolian relief is widespread in the forest-steppe landscapes of Transbaikalia. Valleys of the Selenga River and its inflows are the areas covered by ancient sandy deposits. Human impact in dry climatic conditions causes intensive wind erosion and formation of open and moving sands covered with sparse plants. The flora and vegetation of such landscapes notably differ from surrounding territories. It’s particularity is caused by presence and domination of plant species usually seen on open sands. Despite of numerous publications describing the sandy dunes of Transbaikalia, the psammophyte vegetation and natural dynamics of sandy landscapes are poorly documented. This study presents the analysis of 398 relevés describing psammophyte vegetation from the South-West Transbaikalia (Selenginsky, Dzhidinsky, Kyakhtinsky and Bichursky administrative disticts of the Republic of Buryatia).
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Udoh, B. T., e T. O. Ibia. "Fertility capability classification for agricultural land use planning in the beach sands area of Akwa Ibom State, Nigeria". Agro-Science 21, n. 2 (22 giugno 2022): 74–78. http://dx.doi.org/10.4314/as.v21i2.8.
Testo completoAbstract (sommario):
Soil survey and fertility capability classification (FCC) were carried out in an area mostly underlain by the beach ridge sands (BRS) parent material in Akwa Ibom State, Nigeria. The study applied the FCC in agricultural land use planning for efficient land management and optimal agricultural productivity of the beach soils. Field and laboratory data were obtained from 40 pedons located across eight Local Government Areas on the BRS parent material. From the results of field and laboratory studies, 11 FCC units were identified in the area. Based on similarities in certain soil profile characteristics, the 11 FCC units were grouped into four agro-ecological units (AEUs): (i) poorly drained FCC units with sandy topsoil over sandy subsoil, grouped to form AEU-A, covered 65.00% of study area; (ii) well drained FCC units with sandy topsoil over sandy subsoil, formed AEU-B and covered 22.50% of study area; (iii) poorly drained FCC units with sandy topsoil over loamy subsoil or loamy top- and sub- soils, formed AEU-C and covered 7.50% of study area; (iv) well drained FCC units with sandy topsoil over loamy subsoil, which formed AEU-D, occupied 5.00% of study area. The result of this study has shown that FCC can be employed as a simple but efficient tool in agricultural land use planning. Major soil profile characteristics used to differentiate land units within the beach sands area of Akwa Ibom State are drainage and texture.
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Syvyj, M., e B. Gavrychok. "Construction sands of Podillya: patterns of distribution, resources and use". Journal of Geology, Geography and Geoecology 27, n. 3 (8 gennaio 2019): 510–19. http://dx.doi.org/10.15421/111875.
Testo completoAbstract (sommario):
This article presents the characteristics of the resource base of building sands within the three Podillya regions, the patterns of sands distribution, and proposals for increasing the extraction of raw materials . The construction sands of Podillya are confined to the Upper Cretaceous, Neogene and Anthropogenicdeposits. The decrease of the thickness of the sandy strata of the Opilsk Neogene suite in the eastern direction was observed with the simultaneous increase in the thickness of the overlapping strata of the rocks. There is no apparent correlation between the thickness of sandy interlayers and the quality of sands. The interdependence of the chemical composition of Neogene sands and the sand size module is established.The genetic predisposition for the distribution of building sands in different parts of the Podillya territory has been established. Four groups of sand deposits of different age have been identified within the Podillya regions, which contrast sharply with single deposits in the neighbouring territories.There is a very uneven distribution of explored reserves of sandy raw materials across the region and accordingly in the provision of construction sands in the different oblasts /regions of Podillya. The areas best provided with sandy raw materials are the central districts of Ternopil region and Slavutsky district of Khmelnytsky region . Sands of the Baltic stage distributed in Vinnytsia region are mostly poor in quality, clogged with clay material and require enrichment. The further development of the mineral raw material base and the prospects for increasing the production of construction sand in the Podillya regions is associated with the increase in production at the prepared deposits, the commissioning of reserve deposits, the conducting of prospecting and exploration work in the proposed potentially exploitable areas and additional exploration of individual deposits that are exploited. The research allows us to evaluate objectively the existing base of sand raw materials for various purposes in the Podillya region and to develop on this basis measures to increase it. The importance of the study is determined by the acute shortage of the raw material in most administrative districts of Khmelnytsky and Vinnytsia regions, by the growth in the volume of construction work (and accordingly the requirements for sandy raw materials) both in Podillya and in the country.
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Bulokhov, A. D., e A. M. Petrenko. "Communities of the class Koelerio-Corynephoretea Klika in Klika et Novák 1941 in the Bryansk region of Russia". Vegetation of Russia, n. 30 (2017): 29–34. http://dx.doi.org/10.31111/vegrus/2017.30.29.
Testo completoAbstract (sommario):
Only few publications on the classification of vegetation of Koelerio–Corynephoretea canescentis Klika in Klika et Novák1941 class, that unites pioneer communities on sandy soils, dunes or an exposed sands, is known for Bryansk region of Russia (Bulokhov, 2001; Bulokhov, Kharin, 2008). This region is located in the western part of the East European plain, on the watershed of two large river (Dnieper and Volga) systems, occupying the central part of the Desna river pool and the woody watershed between Desna and Oka. The territory (34.9 thousand кm2) is extended from the west to the east on 270 km (between 31°10′ and 35°20′ E) and from the north to the south — on 190 km (between 54°05′ and 52°10′ N). The main item of this paper is to submit the results of the classification carried out upon thebasis of 57 releves made in 2003–2016 in Bryansk region and to characterize the composition, distribution and syntaxonomical position of thepioneer vegetation of sandy and shallow soils communities within it. Three new associations are described according to Braun-Blanquet floristic classification. The syntaxon nomenclature of the higher ranks follows Mucina et al. (2016) The ass. Thymo serpylli–Koelerietum glaucae ass. nov. hoc loco, with synecological optimum on dry poor sandy soils, is diagnosed by character species Artemisia campestris, Koeleria glauca, Thymus serpyllum. Its communities occur on fringes of the lichen pine forests, sandy river terraces and outwash plains. Two subassociations are distinguished within the association: T. s.–K. g. typicum (with var. typica and Corynephorus canescens) and agrostietosum vinealis subass. nov. hoc loco (with var. typica and Calluna vulgaris) with Agrostis vinealis, Dianthus arenarius, Cladonia arbuscula as differential species. The ass. Koelerio glaucae–Plantaginetum arenariae ass. nov. hoc loco, with synecological optimum on dry poor sandy soils or exposed sands, is diagnosed by Plantago arenaria and Koeleria glauca. Its communities occuron the exposed sands, fringes of lichen pine forests and not flooded sandy river crests. The ass. Diantho borbasii–Festucetum polesicae ass. nov. hoc loco with synecological optimum on dry, weekly acidic, poor of mineral nitrogen, sandy soils or the exposed sands, is diagnosed by Festuca polesica, Astragalus arenarius, Jurinea cyanoides, Otites parviflora. Communities occur on the exposed sands, fringes of lichen pine forests. Two variants are distinguished within association: Sempervivum ruthenicum (on dunes with dry, poor, weekly developed soils) and typica. These three associations are the early stages of the progressive succession of oligotrophic lichen pine forests on the river terraces or of the heath meadows in flood river plains.
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Thevanayagam, S., K. Ravishankar e S. Mohan. "Steady-State Strength, Relative Density, and Fines Content Relationship for Sands". Transportation Research Record: Journal of the Transportation Research Board 1547, n. 1 (gennaio 1996): 61–67. http://dx.doi.org/10.1177/0361198196154700109.
Testo completoAbstract (sommario):
The appropriate choice of shear strength of liquefied sands is an important component in seismic slope stability evaluation. Several factors affect the undrained steady-state strength (Sus) of sands. The steady-state strengths of 24 sandy soils were analyzed. It is shown that fines content, relative density, and friction angle play important roles affecting Sus. Fines content was found to be the major factor affecting Sus. This was verified experimentally for one sand. When the Sus. data for sands were grouped into (a) relatively clean sands (<12 percent fines), (b) silty sands (12 to 50 percent fines), and (c) silts or sandy silts (>50 percent fines), at the same relative density, relatively clean sands showed the highest Sus. Silts showed the lowest Sus. Silty sands showed intermediate strengths. Lower-bound Sus-relative density relationships were established for relatively clean sands and silty sands.
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Aronsohn, Richard B. "“Sandy”". American Journal of Cosmetic Surgery 14, n. 2 (giugno 1997): 208. http://dx.doi.org/10.1177/074880689701400222.
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Rogerson, Andrew, Fiona Hannah, Gwen Hauer e Phillip Cowie. "Numbers of naked amoebae inhabiting the intertidal zone of two geographically separate sandy beaches". Journal of the Marine Biological Association of the United Kingdom 80, n. 4 (agosto 2000): 731–32. http://dx.doi.org/10.1017/s0025315400002563.
Testo completoAbstract (sommario):
Numbers of naked amoebae (Gymnamoebae) inhabiting the lower intertidal zone of two sandy beaches were estimated using a novel enrichment cultivation method. Samples were collected between June and September, 1999. Beach sand at Kames Bay, Isle of Cumbrae, Scotland contained on average 2604 amoebae cm−3 while at Dania Beach, Florida, USA, sand harboured 4236 amoebae cm−3. This is the first study to focus on the abundance of naked amoebae inhabiting a sandy beach. These numbers are higher than densities generally reported for shallow subtidal sands and show that amoebae must be considered in future studies on the dynamics of sandy beach communities.
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Amador, Elmo Da Silva. "Geologia e Geomorfologia da Planície Costeira da Praia do Sul: Ilha Grande - Uma Contribuição à Elaboração do Plano Diretor da Reserva Biológica". Anuário do Instituto de Geociências 11 (1 gennaio 1987): 35–58. http://dx.doi.org/10.11137/1987_0_35-58.
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Based on stratigraphical, sedimentological and geomorphological methods, a preliminary stratigraphic division is proposed to the Praia do Sul coastal plain, a state Biological Reserve, located in "Ilha Grande", Rio de Janeiro. This reserve was created to preserve the natural ecosystems found therein (sandy coastal plain, mangrove, lagoon, rocky coast and hillside fo rest). The Praia do Sul sedimentation plain is essentially constituted by continental gravels and sands of Upper Pleistocene, marine sandy formations, fluvial-lagoonal sandy-clayer formations and present mangrove swamps and beachs. The paleogeographic evolution of this area can be followed through the sedimentary association that permits to establish the transgressive and regressive process that occured during the Quaternary period.
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Deshcherevskaya, E. V., e O. V. Pavlenko. "Response of Sandy and Clayey Soils to Weak And Strong Seismic Loading". Физика земли 2023, n. 4 (1 luglio 2023): 146–62. http://dx.doi.org/10.31857/s000233372304004x.
Testo completoAbstract (sommario):
The response of sandy and clayey near-surface soils representing the classes of noncohesive and cohesive soils to seismic loading of various intensities is analyzed from the in situ data —from the records by vertical groups of the Japanese nationwide KiK-net strong motion seismograph network. For the analysis, out of a total of ~800 stations, we selected five stations with near-surface sandy soils and five stations with near-surface clayey soils, most purely represented in the upper layers. Using the method (Pavlenko and Irikura, 2003), we have constructed and analyzed the models of strong ground motion behavior for “sandy” and “clayey” stations, showing the distributions of earthquake-induced stresses and strains in the soil layers. Close estimates of the amplification of seismic waves in sands and clays at weak seismic ground motion and close stress-strain relationships characterizing the behavior of the near-surface soils at moderate seismic ground motion are obtained. The liquefaction of sandy soils under strong shaking (the 2011 Tohoku earthquake with Мw ~ 9.0) is analyzed. The effects of the extended seismic sources (directivity of their radiation pattern) on the behavior of sandy and clayey soils and the amplification of seismic waves in these soils is studied. Differences in the behavior of sandy and clayey soils are noted only at strong seismic motions: liquefaction in sandy soils is possible if the groundwater level is on the order of a few meters from the surface, while in clayey soils there is no liquefaction.
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Toé Bi, Kizito Katel Kahou, N’goran Jean-Paul Yao, Touvalé Marcel Kessé e Zéli Bruno Digbéhi. "Caracterisation Sedimentologique Et Hydrodynamique Des Formations Sableuses Du Miocene Inferieur De La Region D’eboinda (Sud-Est De La Cote d’Ivoire)". European Scientific Journal, ESJ 12, n. 9 (30 marzo 2016): 192. http://dx.doi.org/10.19044/esj.2016.v12n9p192.
Testo completoAbstract (sommario):
Five hundred and five (505) cuttings samples of 51 survey (of 10 m depth maximum) drilled in Eboinda area (South-western of Côte d’Ivoire) were subject to lithological, mineralogical an granulometry studies in order to clarify the nature of sediments and factors and processes involved during their transport and deposition. The "Surfer" software helps to map the formations. The results indicate: - lithologically:, six mains facies were defined ; sandy clays with gravel, clayey sand, sands, siltyey clay, sandy clays and clay. Sandy sediments were mapped to north and clayed one in south of the study area. Most of studied sands were interpreted as river and coastal dune deposits. Many minerals were described such as sphene, zircon, tourmaline, ilmenite, hematite, apatite, limonite, sillimanite, chromite, muscovite, garnet, chlorite, rutile, goethite, quartz and feldspar. The clay fraction is composed by kaolinite, quartz, apatite, gypsum, goethite and halloysite; - hydrodynamically: the surfacecreep is the main mode of transport expressed within units III and VI. While saltation characterizes sand units IV and V. Predominance of rounded forms and sub-rounded features of quartz grains suggests a transport in aqueous zone over a long distance. In the other hand the sands of units VI and III are essentially sub-angular, suggesting a close generating source. The blunt and shiny aspect of most sands grains encountered, confirm the mode of transport in aqueous zone.
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Chmiel, Stanisław, Stanisław Hałas, Sławomir Głowacki, Joanna Sposób, Ewa Maciejewska e Andrzej Trembaczowski. "Concentration of soil CO2 as an indicator of the decalcification rate after liming treatment". International Agrophysics 30, n. 2 (1 aprile 2016): 143–50. http://dx.doi.org/10.1515/intag-2015-0085.
Testo completoAbstract (sommario):
Abstract This paper presents the results of investigation of decalcification of acid sandy and loamy sand soils by infiltration waters, and potential Ca-leaching after liming treatment. For this purpose, monthly measurements were made of the concentration of CO2 in the soil air, dissolved inorganic carbon in the soil waters, and their ionic composition. The determined dissolved inorganic carbon ranged from 5.9 to 10.6 mg dm−3 and from 9.9 to 16.5 mg dm−3 for the sandy and loamy sand soil, respectively. The Ca concentration in soil waters was determined as 5.9-12.4 mg dm−3 in sandy soil and 14.2-19.8 mg dm−3 in soil loamy sand. The calculated rate of decalcification amounted to 23.0 kg ha−1 year−1 in soil sandy and 19.4 kg ha−1 year−1 in loamy sand soil. The potential Ca-leaching is predicted as 124 kg ha−1 year−1 for S and 87 kg ha−1 year−1 for loamy sand soil. At the treatment level of 3 000 kg ha−1 4 year−1 of CaO, ~20% of the Ca-fertilizer can be leached after the liming treatment. The results of the CO2 concentration in the soil air may be useful in estimation of Ca-leaching from soils developed by slightly clayey sands and clayey sands in zones with a moderate climate.
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Likhanova, I. A., E. G. Kuznetsova, Yu V. Kholopov, S. V. Deneva e E. M. Lapteva. "Primary pedogenesis on different texture substrates in post-technogenic ecosystems of the taiga zone". Theoretical and Applied Ecology, n. 1 (25 marzo 2024): 122–30. http://dx.doi.org/10.25750/1995-4301-2024-1-122-130.
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The paper focuses on the primary soil formation under automorphic conditions in the middle taiga sub-zone of the European North-East of Russia (Komi Republic) on the post-technogenic territories (quarries for the extraction of minerals (construction sand)) with different soil materials (ancient alluvial sands; fluvioglacial sands and sandy loams, moraine loams). In the quarries, the processes of soil formation and vegetation cover development are interdependent and are affected by the properties of soil-forming rocks. Along with the improvement of soil properties (from sandy loam to loam), the biometric parameters of pine stands increase; in the ground cover, dominating lichens are replaced by mosses, and then by grasses. The biogenic accumulation rates of organic matter increase along with the transition of soil material to fine-textured. In automorphic conditions, the accumulation rate of Corg. in soil of sandy quarry under sparse young lichen pine forest reaches 0.1, in sandy loam under young forb-moss pine forest – 0.3, in loam under young grass-forb pine forest – 0.6 t/ha/year. Already in the first succession decades, every study soil demonstrates weakly expressed processes of eluviation and illuviation (the beginning of podzolization). These processes are evidenced by morphological signs (the appearance of bleached quartz grains and whitish patches under organic horizon and in its lower part), redistribution of silicon, iron, and aluminum compounds, as well as of silty particles proportion.
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Qualls, Larry. "Sandy Skoglund". Performing Arts Journal 16, n. 1 (gennaio 1994): 102. http://dx.doi.org/10.2307/3245831.
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Ahmadi, Ramin. "Sandy Hook". Annals of Internal Medicine 158, n. 3 (5 febbraio 2013): 218. http://dx.doi.org/10.7326/0003-4819-158-3-201302050-00017.
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Pollak, Cheryl L. ""Hurricane" Sandy". Texas A&M Journal of Property Law 5, n. 2 (dicembre 2018): 157–92. http://dx.doi.org/10.37419/jpl.v5.i2.3.
Testo completoAbstract (sommario):
On the evening of October 29, 2012, “Hurricane” Sandy made land- fall on the New York coastline, battering the land with strong winds, torrential rain, and record-breaking storm surges. Homes and commercial structures were destroyed; roads and tunnels were flooded; and more than 23,000 people sought refuge in temporary shelters, with many others facing weeks without power and electricity. At the time, Sandy was heralded as one of the costliest hurricanes in the his- tory of the United States; the second costliest hurricane only to Katrina, which hit New Orleans in 2005. Unfortunately, recent experience with Hurricanes Florence, Maria, Harvey, and Irma suggest that this pattern of devastating superstorms may become the new norm as climate change produces more extreme and unpredictable weather events. In Sandy’s aftermath, as individuals returned to their homes, or what remained of them, and communities began to rebuild, the true cost of the storm became apparent. A year after the storm, the Federal Emergency Management Agency (“FEMA”) estimated that over $1.4 billion in assistance was provided to 182,000 survivors of the dis- aster; another $3.2 billion was provided to state and local governments for debris removal, infrastructure repair, and emergency protective measures. More than $2.4 billion was provided to individuals and businesses in the form of low-interest loans through the Small Business Administration (“SBA”), and millions more were spent on grants de- signed to implement mitigation measures in the future and to provide unemployment assistance to survivors. Before the storm, homeowners paid premiums for flood insurance provided through the National Flood Insurance Program (“NFIP”), and for homeowner’s insurance provided by dozens of private insurers. In the months following the storm, they began to file claims for assistance in rebuilding their homes. While many such claims were re- solved successfully, many homeowners were unhappy with the settlement amounts offered by their insurance carriers and felt compelled to file lawsuits in the surrounding state and federal courts. Many of those lawsuits were filed in the United States District Court for the Eastern District of New York (“EDNY”). This case study describes the EDNY’s specifically crafted, unique approach to handling the mass litigation that ensued from Sandy’s devastation, documents some of the problems that the Court faced during that mass litigation, and describes some of the lessons learned from the Court’s experience.
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Newton, Alicia. "Sandy storehouse". Nature Climate Change 1, n. 805 (17 aprile 2008): 50. http://dx.doi.org/10.1038/climate.2008.34.
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Lindsey, Heather. "Hurricane Sandy". Nephrology Times 5, n. 12 (dicembre 2012): 8–11. http://dx.doi.org/10.1097/01.nep.0000426009.16085.b8.
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Healy, Sonya, e Gundersen Lutheran. "Sandy Littlejohn". Nurse Leader 4, n. 3 (giugno 2006): 10–13. http://dx.doi.org/10.1016/j.mnl.2006.04.001.
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Hewitt, Paul. "SANDY BOTTOM". Physics Teacher 46, n. 8 (novembre 2008): 454. http://dx.doi.org/10.1119/1.2999058.
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Trento, Laura, e Sarah Allen. "Hurricane Sandy". Nutrition in Clinical Practice 29, n. 5 (25 giugno 2014): 576–84. http://dx.doi.org/10.1177/0884533614536927.
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Richter, Matt. "Occupy Sandy". Disaster Medicine and Public Health Preparedness 6, n. 4 (dicembre 2012): 324. http://dx.doi.org/10.1001/dmp.2012.75.
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Lange, Ivan, Pavel Kotiukov e Yana Lebedeva. "Analyzing Physical-Mechanical and Hydrophysical Properties of Sandy Soils Exposed to Long-Term Hydrocarbon Contamination". Sustainability 15, n. 4 (15 febbraio 2023): 3599. http://dx.doi.org/10.3390/su15043599.
Testo completoAbstract (sommario):
This paper aims to investigate the issue of sandy soil contamination by oil hydrocarbons. Laboratory procedures used to study conditionally pure and contaminated sands include grain-size measurements and evaluation of physical-mechanical and hydrophysical properties. The results of the analysis of sand samples using visual and microscopic studies and sieve analysis show that, unlike in conditionally pure sands, in contaminated samples, the surface of mineral particles is covered by hydrocarbon film. The presence of the latter enables micro- and macroaggregates to be formed. Studies of the physical and hydrophysical properties of sands using a technique with pre-weighed glass containers, as well as a filtering device, SPETSGEO pipes, showed that, in comparison with conditionally pure samples, contaminated specimens of sandy soils have lower densities and higher permeabilities and water yields. Testing the mechanical properties of contaminated sands on the GPP-30 direct shear apparatus using the consolidated dried shear strength method revealed an increase in the angle of internal friction with a decrease in specific adhesion compared to conditionally clean sands.
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Yatsyshyn, Andriy, Maciej Bąbe, Danuta Olszewska-Nejber, Andriy Bogucki e Stephania Vas’kiv. "Lithological and sedimentological characteristics of the alluvium of the sixth terrace of the Dniester river (Loyeva level) in the Torhanovychi 2 section". Visnyk of the Lviv University. Series Geography, n. 41 (17 settembre 2013): 382–95. http://dx.doi.org/10.30970/vgg.2013.41.2011.
Testo completoAbstract (sommario):
The main lithological characteristics of the alluvium of the sandy-gravelly bed of the sixth terrace of the Dniester river (Loyeva level) at environs of Sambir was analysed, in particular textural elements, granulometric and petrographic composition of the gravelly material (enclosing coarse sands, granules, pebbles, cobbles and boulders), its roundness, and the orientation of grains. The conditions of sedimentation of the studied alluvial sandy-gravelly bed of the sixth terrace of the Dniester river (Loyeva level) were reconstructed. Key words: granulometric composition, petrographic composition, roundness, sorting, imbrication, braided channel, depositional conditions.
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Łabuz, Tomasz Arkadiusz, Ralf Grunewald, Valentina Bobykina, Boris Chubarenko, Algimantas Česnulevičius, Artūras Bautrėnas, Regina Morkūnaitė e Hannes Tõnisson. "Coastal Dunes of the Baltic Sea Shores: A Review". Quaestiones Geographicae 37, n. 1 (30 marzo 2018): 47–71. http://dx.doi.org/10.2478/quageo-2018-0005.
Testo completoAbstract (sommario):
Abstract The article summarises results of studies conducted along the Baltic Sea sandy coasts by scientists involved in coastal dune research, and presents an attempt to describe the types and distribution of dune coasts. The Baltic Sea coasts feature lower and higher foredunes. The lowland behind the coastal dune belt is covered by wandering or stabilised inland dunes – transgressive forms, mainly parabolic or barchans. The source of sediment for dune development includes fluvioglacial sands from eroded coasts, river-discharged sand, and older eroded dunes. Due to the ongoing erosion and coastal retreat, many dunes have been eroded, and some are withdrawing onto the adjacent land. There are visible differences between the south-eastern, western, and northern parts of the Baltic Sea coast with respect to dune development. The entire southern and eastern coast abounds in sand, so the coastal dunes are large, formerly or currently wandering formations. The only shifting dunes are found at the Polish and the Russian–Lithuanian coasts on the Łebsko Lake Sandbar as well as on the Vistula and Curonian Spits. The very diverse shoreline of the south-western coast experiences a scarcity of larger sandy formations. Substantial parts of the Baltic Sea sandy coasts have been eroded or transformed by humans. The northern part of the Baltic Sea coast features mainly narrow and low sandy coasts (e.g. in Estonia). Further north, sandy dunes are virtually absent.
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Stanila, Anca Luiza, Catalin Cristian Simota, Iulian Ratoi, Aurelia Diaconu e Mihail Dumitru. "Research on Improving Fertility Sandy Soils from Dabuleni Field by Administration of Loess". Revista de Chimie 70, n. 2 (15 marzo 2019): 543–48. http://dx.doi.org/10.37358/rc.19.2.6952.
Testo completoAbstract (sommario):
In order to solve and clarifying certain aspects of the clay content (particles [0.002 mm) sands and sandy soils, humus, respectively, the process of bioaccumulation and mineralization the organic matter of the land, in the Research and Development Centre for Plant Growing on Sand Dabuleni, have initiated research aimed at finding methods and means for accumulating and thus the increase in the content of clay in the soil, respectively humus.Therefore, to improve radical of sandy soils, we found it necessary to resort to what is called loess process. It consists in enriching the horizon the surface soil (20-25 cm) the fraction with 8-10% clay, to 1.5-5%, as currently it contains. It is primarily intended to influence various amounts loess material on physical, hydro- physical and chemical properties of soils, then the plant response to changes products in the soil, increasing the guaranteed potential fertility of these soils, which will result in production high and constant.Obtaining appropriate agricultural production on sandy soils (eutric psamosol) it is limited not only by the soil, but also other factors such as relief, drainage and even climate. Because coarse texture, water-holding capacity in the case of sandy soils it is very low in all soils, the clay content below 5% production capacity of soils it is particularly low in the absence of agropedoameliorative measures and especially irrigation. Wind erosion occurs in all perimeters sandy soils, with higher intensity is observed in Oltenia Plain (Dabuleni Field).
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Guan, Chengli, e Yuyou Yang. "Field Study on the Waterstop of the Rodin Jet Pile Method in a Water-Rich Sandy Gravel Stratum". Applied Sciences 9, n. 8 (25 aprile 2019): 1709. http://dx.doi.org/10.3390/app9081709.
Testo completoAbstract (sommario):
Due to the increasing depths of underground urban construction, the surrounding environment and hydrogeological conditions are becoming increasingly complex, and conventional high-pressure rotary jet grouting has become unable to meet construction needs. At present, Rodin jet pile (RJP) ultra-high-pressure rotary jet grouting has been widely used as a grouting reinforcement method for deep and large foundations in silty soils, fine sands and clay strata; however, there have been no successful applications in a sandy gravel stratum with high water content (namely, water-rich sandy gravel stratum). Therefore, this paper uses the ventilating shaft in a section of the Beijing Metro as the construction background to carry out field tests on the RJP ultra-high-pressure rotary jet grouting method and waterstop in a water-rich sandy gravel stratum. Through a series of experiments monitoring the formation deformation and pore water pressure and exposing the pile diameter, pile occlusion, pile strength, and permeability of the test pile construction process, it is believed that, for the RJP ultra-high-pressure construction method in a water-rich sandy gravel stratum, reliable jet solidification can occur, the joint between jets can be achieved, the solid strength can reach 10 MPa or higher, and the permeability coefficient can reach 10−8 cm/s. Therefore, RJP ultra-high-pressure rotary jet grouting can be applied as a waterstop method in water-rich sandy gravel stratum.
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Cauxeiro, Cirilo, Michel Lopez, Javier Hernández-Molina, Artur Miguel, Gizela Cauxeiro e Vanessa Caetano. "Contourite vs Turbidite Outcrop and Seismic Architectures". Angolan Mineral, Oil & Gas Journal 1, n. 1 (6 maggio 2020): 20–26. http://dx.doi.org/10.47444/amogj.v1i1.9.
Testo completoAbstract (sommario):
The hydrocarbon exploration of oceanic depositional systems demands a better understanding of the role of bottom currents and their implications for petroleum systems such as reservoir and sealing rocks. Deep-marine bottom-current reworked sands (sandy contourites) have been recognized in hydrocarbon-bearing sands of the Kwanza Basin. Such understanding implies additional alternatives for the definition of exploration targets and prospect risk reduction. The southernmost part of the Kwanza Basin (Miradouro da Lua zone) comprises one of the best outcrops of contourites deposits, formed during the Miocene and Pliocene age. Laterally, coeval sandy deposits are found offshore Kwanza Basin along the continental margin, and have been one of the great challenges for the oil companies operating in Angola. Therefore, the aim of the current proposal is to characterize sandy contourite deposits at Miradouro da Lua and compare them with offshore deep-water sandy deposits, evaluating their conceptual and economic implication. Modern field sedimentology technique merged with reflection seismic data and other geographic information system (GIS) techniques, allow the characterization and proposal of a stratigraphic architecture diagram that explains the interaction of the deep-marine processes, especially gravitational (down-slope) and bottom current (along-slope) processes as well as its vertical and spatial association. Sonangol (Angolan State Oil Company) and Total (French Multinational Company) explore similar deposits in Block 48 in Ultra deep-sea, and they will also reactivate the exploration of the Iabe Formation in Block 4. The Tertiary Stratigraphic Architecture in Blocks 6, 7, 8, 19 and 20 are similar to the Lower part of the Miradouro da Lua zone. All these observations and data are very important to calibrate oil reservoir models.
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Kamoona, Suhair, Razanah Ramya, Wan Masyitah Wan Daud, Farah Ayuni Mohd Hatta e Rashidi Othman. "Properties of sandy soil and allelochemical compounds of heath forest in Rantau Abang, Terengganu, Malaysia: Implication for ecological sustainability and biodiversity conservation". International Journal of Innovative Research and Scientific Studies 6, n. 2 (22 marzo 2023): 344–57. http://dx.doi.org/10.53894/ijirss.v6i2.1432.
Testo completoAbstract (sommario):
Kerangas or heath forests are found on podzolised siliceous sands (spodosols), where gradually decomposing organic matter occurs on the soil’s surface. Changes in the extent of podzol development, soil consistency, and poor nutrient contents signify the unique properties of sandy soil in the heath forest at Rantau Abang, Terengganu, Malaysia. Unfortunately, the sandy soil’s chemical and physical properties are in critical condition due to human activities such as cutting and burning, impacting the sustainability of this ecosystem and its ground cover of shrubs, sparse grass and sedge. Therefore, it is crucial to study the properties of sandy soils in heath forests before their extinction. This analyzed the physical and chemical attributes of heath forest sandy soils regarding heavy metal toxicity, pH, concentrations of carbon, nitrogen, available phosphorus, cation exchange capacity (CEC), allelochemical compounds, total phenolic content in the soil, soil colour, and soil texture. The solid was found to be nutrient-deprived due to its extreme acidity and toxicity. The results showed that allelochemical matters were higher in plants but not in the soil attributes and the water bodies, along with a highly active response in young plant tissues due to their sources of phenolic content. Remarkably, the overall phenolic content was observed to be considerably high in the semi-mature phase of vegetation.
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RYASHCHENKO, TAMARA, e STANISLAV MAKAROV. "Mineral composition of eluvial and aeolian sands (on the example of the unique collection of samples)". Domestic geology, n. 5 (15 novembre 2022): 59–69. http://dx.doi.org/10.47765/0869-7175-2022-10030.
Testo completoAbstract (sommario):
The object of the research is the unique collection of samples of eluvial and aeolian sands collected in the tropical (Vietnam) zone and the zone with the temperate humid sharply continental climate (the Tunkinsk’s depression in the Baikal region). Traces of structural connectivity were established by visual inspection of the samples in laboratory conditions using a four-fold magnifier. "Cohesive" clayey (ps*) and ordinary sandy (ps) varieties were identified. The mineral composition of the collection sands was determined by the method of quantitative immersion analysis of the 0.25–0.05 mm fraction. The composition and morphological characteristics of various light and heavy terrigenous minerals were determined, and special coefficients were calculated using the method of quantitative immersion analysis. Beforehand, the granulometric analysis of samples was carried out using A.N. Sabanin's method. As a result, the fraction for mineralogical studies was isolated, and the content of sandy-pulverescent and clay particles was established. The research goal consists of a comparative analysis of the mineral composition of the sands, the degree of their chemical maturity, and the investigation of possible variants of structural connectivity formation.
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Sun, Lei, Yuanyun Xie, Chunguo Kang, Yunping Chi, Peng Wu, Zhenyu Wei, Siqi Li, Qian Zhao e Shuo Liu. "The composition of heavy minerals of the sandy lands, Northeast China and their implications for tracing detrital sources". PLOS ONE 17, n. 10 (20 ottobre 2022): e0276494. http://dx.doi.org/10.1371/journal.pone.0276494.
Testo completoAbstract (sommario):
Comprehending heavy mineral composition of the sandy land in Northeast China (NESL) is of great significance for interpreting generation, pathways, source and geochemistry of sediments in this area. To this end, the fine-grained (<63 μm) aeolian-fluvial sediments and loess deposits, which were taken from the Onqin Daga Sandy Land, the Horqin Sandy Land, the Hulun Buir Sandy Land and the Songnen Sandy Land, and from the downwind loess section (L1), respectively, were analyzed to construct the heavy mineral data set of NESL source and sink and to evaluate feasibility of the heavy mineral method in tracing the source of aeolian dust in Northeast China. Additionally, the <63 μm, 63–125 μm and 125–250 μm fractions of the fluvial sands from the different Balan River reaches having a same source, were analyzed to valuate the impact of the river transport-sedimentation process on the heavy mineral composition. The results show that the NESL shows moderate similarities in the heavy mineral composition, with ilmenite, epidote, zircon and amphibole as the primary minerals. In the source-to-sink system in the NESL, limited by sedimentary differentiation, post-deposition alteration and similar source material composition, the heavy mineral composition of the loess and that of sandy-land sources does not well correlate, indicating single heavy mineral method is incapable of unequivocally detecting loess sources when not considering the physical geographical conditions. The sediments in the different Balan River reaches show clear diversities and grain-size dependency in heavy minerals composition, indicating the river transport-deposition processes exert a clear control on the heavy-mineral composition in the sediment downstream. Both a wide grain-size window and more numbers of samples are needed to obtain a complete heavy-mineral picture in the source area.
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Caputa, Zbigniew. "The structure of the radiation balance on a sandy surface: case the Błędów desert, Silesian Upland". Ekológia (Bratislava) 35, n. 2 (1 giugno 2016): 114–25. http://dx.doi.org/10.1515/eko-2016-0009.
Testo completoAbstract (sommario):
AbstractComprehensive environmental studies taking under consideration the structure of the radiation balance during the vegetation growing seasons of 2001 and 2002 were carried out on the open sandy surface of the area called the Błędów ‘desert’ located on Silesian Upland. The research in each site covered the composition of plant species, their age and height, the condition of the substratum, the composition and structure of the soil and the meteorological conditions with elements of the radiation balance. The article presents some part of the research on meteorological elements and their impact on ecosystem. Special attention was devoted to radiation conditions on the open sandy surface in the context of the formation of BSC (biological soil crust). Having presumed that the values obtained on the grassy surface constituted 100%, the values of radiation reflection measured on the open sandy surface were 185% higher and the values of net longwave radiation were 105% higher in day time and 137% in night time. Values of net radiation of about 63% lower were observed on the sandy surface during a typical sunny summer day. It was found that a strong irradiation of the sandy surface (26 MJ·m–2d–1) creates extremely difficult conditions for the initiation of the process of ecosystem formation (including BSC or plant succession). The elements of the radiation balance, net radiation, albedo and temperature of the open sandy surface were represented quantitatively. The test surfaces were classified based on the value of the albedo: group I with low albedo values, up to 0.15 (spore-bearing plants on a dark surface), including BSC; group II with mean values of the albedo from 0.16 to 0.24 (spore-bearing plants and seed on a dark grey surface); and group III with high albedo values, above 0.25 (plants growing on bare or loose sands).
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Sukach, Mykhailo, e Svitlana Komotska. "Investigation of thixotropy of underwater silty soils". Gіrnichі, budіvelnі, dorozhnі ta melіorativnі mashini, n. 99 (23 dicembre 2022): 28–33. http://dx.doi.org/10.32347/gbdmm.2022.99.0302.
Testo completoAbstract (sommario):
In the natural state, thixotropic phenomena in soils most often occur under external loads of a dynamic nature: earthquakes, vibrations from moving vehicles, working machines and mechanisms. Data on the study of soil thixotropy indicate that under dynamic load to reduce the strength and go into a liquid state can be dispersed soils of different types, genesis and age. The influence of dynamic loading is especially significant in the case of poorly compacted and water-saturated sandy and clay soils.
At dynamic loading there can be both consolidation of soil and accordingly increase in its durability, and decrease in durability. More often it is necessary to face processes of decrease in durability and thinning of soils at dynamic influence. The most studied processes occurring in water-saturated sands. The state of liquefaction during vibration occurs due to the destruction of contacts between individual grains, the strength of sandy soil drops to almost zero. After removing the vibration load, the grains of sand under the influence of their own weight move down, causing compression of the liquid phase. The more sands contain fine particles and organic matter, the longer they retain a liquid state, the slower the squeezing of water and compaction. The possibility of thinning sandy soils is determined not so much by natural porosity, but by the stress of the soil and the nature of vibration.
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DECKERS, Jef, Dirk MUNSTERMAN, Roel DE KONINCK e Marco SCHILTZ. "Facies variability of the Lower Miocene Houthalen Member in the southern Genk municipality (northeastern Belgium)". Geologica Belgica 27, n. 1-2 (31 luglio 2024): 33–46. http://dx.doi.org/10.20341/gb.2024.003.
Testo completoAbstract (sommario):
The Oligocene Eigenbilzen Formation and Miocene Bolderberg Formation were studied along the Albert Canal in the southern Genk municipality, eastern Belgium. Previous studies have subdivided the Eigenbilzen Formation into geophysical subunits based on borehole logs. Correlations of borehole logs with a deep Cone Penetration Test reveal that this subdivision is also geotechnically distinct. The Eigenbilzen Formation is unconformably overlain by the Houthalen Member (lower Bolderberg Formation), which holds a late Burdigalian age according to the dinoflagellate cyst analyses on borehole samples by this study. The average glauconite, organic and carbonate content of the Houthalen Member in the study area is 8.2%, 0.5% and 3%. Within the Houthalen Member, we distinguished two different geotechnical CPT and lithological facies, herein referred to as clayey and sandy facies. Granulometric analyses indicate that both facies are dominated by fine sands, however, with the sandy facies having an average 5.1% fine fraction (<63 µm), and the clayey facies 18.8%. The clayey facies is very distinct, whereas the sandy facies is geotechnically and granulometrically similar to the superjacent Genk Member (upper Bolderberg Formation). Besides carbonate content, the main difference between the sandy Houthalen Member and the Genk Member is the larger glauconite content of the first. As the glauconite content decreases upwards in the sandy Houthalen Member, it transitions into the Genk Member. Along the 3.6 km long correlation panel, the clayey Houthalen Member thins from over six meters in the southeast towards less than one meter in the northwest, which highlights the sedimentological complexity within the unit.
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Aziz, Mike, e Alexis Georges. "Aménager après Sandy". Outre-Terre 35-36, n. 1 (2013): 483. http://dx.doi.org/10.3917/oute.035.0483.
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Urquhart, Steve. "Sandy Ross Urquhart". Veterinary Record 188, n. 5 (marzo 2021): 196. http://dx.doi.org/10.1002/vetr.282.
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Neal, Ryann, e Robert Fischer. "Weathering SuperStorm Sandy". Proceedings of the Water Environment Federation 2014, n. 17 (1 ottobre 2014): 2320–38. http://dx.doi.org/10.2175/193864714815943557.
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Roulstone, Ian, e John Norbury. "Computing Superstorm Sandy". Scientific American 309, n. 2 (17 luglio 2013): 22. http://dx.doi.org/10.1038/scientificamerican0813-22.
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Ersel, Murat. "Aftermath Hurricane Sandy". Journal of Academic Emergency Medicine 12, n. 2 (24 maggio 2013): 110–11. http://dx.doi.org/10.5152/jaem.2013.032.
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Chambers, G. "Alexander 'Sandy' Smith". International Journal of Dairy Technology 55, n. 4 (novembre 2002): 217–18. http://dx.doi.org/10.1046/j.1471-0307.2002.00074.x.
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Hutner, H. "Hurricane Sandy Diary". Interdisciplinary Studies in Literature and Environment 21, n. 1 (19 marzo 2014): 59–67. http://dx.doi.org/10.1093/isle/isu019.
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Hardy, R. "Sandy Holt-Wilson". BMJ 349, jul25 7 (25 luglio 2014): g4846. http://dx.doi.org/10.1136/bmj.g4846.
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Weeks, C. "Sandy (Alexander) Pinkerton". Spinal Cord 49, n. 3 (marzo 2011): 322. http://dx.doi.org/10.1038/sc.2010.135.
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Bessou, Anne-Line, e Sandy Skoglund. "Sandy Skoglund. Entretien". Figures de l'Art. Revue d'études esthétiques 22, n. 1 (2012): 309–11. http://dx.doi.org/10.3406/fdart.2012.1007.
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Malekoff, Andrew. "Sandy and Sandy in Seven Weeks: A Group Worker Reflects". Social Work With Groups 36, n. 4 (ottobre 2013): 285–91. http://dx.doi.org/10.1080/01609513.2013.796543.
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Sivapalan, S. "Benefits of treating a sandy soil with a crosslinked-type polyacrylamide". Australian Journal of Experimental Agriculture 46, n. 4 (2006): 579. http://dx.doi.org/10.1071/ea04026.
Testo completoAbstract (sommario):
The productivity of sandy soils is mostly limited by their low water-holding capacity and excessive deep percolation losses, which reduce the efficiency of water and fertiliser use by plants. The effect of a crosslinked-type polyacrylamide, ALCOSORB 400, on water-holding capacity of a sandy soil, siliceous sands, was studied under the laboratory and glasshouse conditions. Water-holding capacity of the soil exposed to 0.01 MPa increased by 23 and 95% by adding 0.03 and 0.07% of polyacrylamide to the soil, respectively. This indicated that the soil treated with polyacrylamide was able to store more water than untreated soil, thereby reducing the potential losses due to deep percolation in sandy soils. However, the polyacrylamide in the treated soil did not significantly increase the quantity of water released from the soil by increasing the pressure from 0.01 to 1.5 MPa. The results from the first glasshouse experiment demonstrated that the excess amount of water stored in the soil by polyacrylamide was available to plants and resulted in higher water use and grain production. Consequently, there was a 12 and 18 fold increase in water use efficiency of soybean plants grown in soils treated with 0.03 and 0.07% polyacrylamide, respectively. The results from the second glasshouse experiment demonstrated that increasing amounts of polyacrylamides in a sandy soil can extend the irrigation interval without any adverse effect on the grain yield of soybeans.
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Vykhovanets, G. V., A. B. Murkalov e A. A. Stoyan. "DYNAMICAL STEADINESS OF SANDY BEACHES SIZES IN THE BLACK SEA COASTAL ZONE". Odesa National University Herald. Geography and Geology 19, n. 1(20) (6 aprile 2015): 53–68. http://dx.doi.org/10.18524/2303-9914.2014.1(20).40571.
Testo completoAbstract (sommario):
Sandy beaches are representing primary accumulative shore forms within a surf impact site in coastal zone of a Seas. Usual beaches was made up by drifts and its are most dynamic accumulative forms. They are changing during every storm, they can have expansion and diminution in environment that were formed during past centuries. During past decades began exact instrumental measurements of sandy beaches on natural sites. As a result, various calculative linear and volumetrical beach values were discovered.Sandy beaches are significant recreational resource and mean of natural defence of native shores against wave abrasion. It is basic state indicator of the coastal zone nature features and source of sand and gravel sediments for building usage. In natural coastal condition of the Black Sea shoreline deformation constitute ±47 m maximal along bars and spits and along active cliffs up to ±23 m during decades on the stationary sites. During long time in most causes vertical stormy deformations of a beach surfaces can be ≤ 2,8 m on accumulative coastal relief forms, and along abrasive slopes its limited by thickness of beach stratum sands. On every coastal sector with resemble physical-geographical sandy beaches to-wards gravitate by average linear and volumetric sizes, in spite of stormy values sparseness. Within all of the Black Sea sandy beaches are developing in condition of acute drift deficit.
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Lizana Olarte, Diego Edson Meliton, Zenón Aguilar-Bardales e Diana Lucia Calderón-Cahuana. "Estimación de la curva característica suelo agua en suelos arenosos mediante el ensayo de papel filtro". TECNIA 33, n. 1 (2 agosto 2023): 52–60. http://dx.doi.org/10.21754/tecnia.v33i1.1397.
Testo completoAbstract (sommario):
The unsaturated soils mechanics is strongly related to the suction phenomenon that occurs between solid soil particles, which changes when the soil water content does not remain constant. The soil-water characteristic curve (SWCC) provides information related to suction and water content of the soil; and to obtain such a curve different direct and indirect methods can be used. In this research the soil-water characteristic curve for sands is obtained through the implementation of the filter paper test. For this purpose, three reconstituted samples of sandy soils from Lima – Peru (relative density between 20% and 60%) were tested following the wet path of the curve. The samples were stored at least seven days until equilibrium was reached. In this way, discrete points of the soil-water characteristic curve were obtained. SWCC equations such as Brooks and Corey (1964), Van Genuchten (1980), and Fredlund and Xing (1994) were used to adjust the data and obtain their respective parameters for sandy soils. Results show that the filter paper test can be used to obtain the soil-water characteristic curves of reconstituted sandy soils; and that the matric suction of sandy soil can be obtained in seven days period by means of this method; whereas a longer storage time could require to reach the equilibrium and to obtain the total suction for these soils.
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Xu, Yan, Zhaoyang Cai, Kaige Wang, Yuwei Zhang e Fengrong Zhang. "Evaluation for Appropriate Tillage of Sandy Land in Arid Sandy Area Based on Limitation Factor Exclusion Method". Land 11, n. 6 (30 maggio 2022): 807. http://dx.doi.org/10.3390/land11060807.
Testo completoAbstract (sommario):
Investigating and evaluating the quantity and spatial distribution of arable sandy land in arid and semiarid sandy areas is of great significance for the sustainable development and utilization of sandy land resources and the maintenance of the stability of the structure and function of regional ecosystems. Based on the characteristics of sandy soil, being without structure and susceptible to wind erosion, this study used the limiting factor exclusion method to investigate and evaluate arable sandy land in arid and semiarid areas. All sandy soils were taken as the evaluation objects of arable sandy land (including visible sandy land and invisible sandy land). On the basis of following the principle of ecological protection, the evaluation indicators and limiting factor exclusion evaluation methods of arable sandy land were determined. The results of Hangjin Banner are as follows: the total area of the visible sandy land and the recessive sandy land was 1.2 × 106 hm2; the visible sandy land accounted for 42.6%, and the invisible sandy land accounted for 57.5%. However, only 7.7% of the sandy land was suitable for farming, which is the current cultivated land of bare sand and sandy soil, extremely-low-coverage grassland, inland tidal flats, and other saline-alkali land. Even if these arable sandy lands are to be used sustainably after reclamation, reasonable ecological protection, irrigation engineering measures, and field protective farming measures must be taken. It is hoped that this study can provide a valuable reference for the sustainable development and utilization of arable sandy land and desertification control in arid and semiarid areas.