Journal articles on the topic 'SANDY SOIL MIXED'
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1
Kim, Ungjin, and Dae Sang Kim. "Field studies on low and fast compressibility of cement-mixed gravel in railway embankment construction." PLOS ONE 18, no. 8 (August 18, 2023): e0288884. http://dx.doi.org/10.1371/journal.pone.0288884.
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The cement-mixed gravel, which is used in the construction of railway embankment, is a relatively more expensive material compared to sandy soil. Having said that, it is used where small residual settlement is required for example, abutment transition zone, due to characteristic of higher strength than sandy soil. In this paper, the time-dependent settlement were evaluated using field data measured over a long period of time at two RSR (Reinforced Subgrade for Railways) construction sites using two different backfill materials (sandy soil and cement-mixed gravel). The embankment settlement with cement-mixed gravel as a backfill material was reduced by 78% compared to that with sandy soil. Further, the period for stabilizing the embankment before installation of the railway track was significantly reduced with cement-mixed gravel as a backfill material.
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Willingham, S. D., N. R. Falkenberg, G. N. McCauley, and J. M. Chandler. "Early Postemergence Clomazone Tank Mixes on Coarse-Textured Soils in Rice." Weed Technology 22, no. 4 (December 2008): 565–70. http://dx.doi.org/10.1614/wt-08-051.1.
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Clomazone was labeled for rice in 2001; however, that label excluded its use on coarse- (light) textured soils, including sand, loamy sand, and sandy loam with less than 1% organic matter due to rice injury. Field studies conducted in 2005, 2006, and 2007 evaluated weed control and tolerance of rice to early postemergence (EPOST) applications of clomazone alone and tank mixed with other herbicides on sandy loam and clay loam soils. At 42 d after treatment (DAT), broadleaf signalgrass (BRAPP) and barnyardgrass (ECHCG) control was > 86%. At 14 DAT, rice injury was greatest (13%) from clomazone applied preemergence (PRE) at 0.44 kg ai/ha on sandy soil. Annual sedge (CYPCP) control was > 78% on sandy loam soils at 14 DAT, but increased to > 90% by 42 DAT. On clay loam soils, CYPCP control at 42 DAT ranged from 60 to 76% from clomazone alone or tank mixed with cyhalofop or fenoxaprop. All other tank mixes provided > 80% control. Hemp sesbania (SEBEX) control was > 80% from all tank mixes. Clomazone alone provided < 77% control. Data suggest that clomazone can be used EPOST in combination with other herbicides without causing significant rice injury on sandy loam soils in Texas.
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Nurhayati, Dewi Ratna, Prapto Yudono, Taryono Taryono, and Eko Hanudin. "Pengaruh Waktu Pemupukan pada Dua Musim Tanam terhadap Karakter Wijen Sbr-1 dan Sbr-3 di Lahan Pasir Pantai." Caraka Tani: Journal of Sustainable Agriculture 33, no. 1 (April 4, 2018): 19. http://dx.doi.org/10.20961/carakatani.v33i1.19442.
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Sesame is recognized as healthy potential oil crops because can be used to control several diseases. Sesame can grow properly in light soil structure such as sandy coastal soil, however sandy soil is considered as unfertile one and therefore environmental friendly fertilizer application based on dung manure must be studied. The research toinvestigate the influence of application times of mixed fertilizer on the growth sesame in quality growth in coastal sandy soil both at rainy and dry seasons, therefore the experiment directly to the sandy field at the sandy coastal area of Keburuhan, Purworejo, Central Java. From the first stage, it could be said that the application of mixed fertilizer between chicken manure and inorganic fertilizer increasing tochlorophyll content, net assimilation rate, root volume sesame both in rainy and dry seasons.
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Masood, Tareq K., and Nooruldeen S. Ali. "Effect of Different Soil Organic Carbon Content in Different Soils on Water Holding Capacity and Soil Health." IOP Conference Series: Earth and Environmental Science 1158, no. 2 (April 1, 2023): 022035. http://dx.doi.org/10.1088/1755-1315/1158/2/022035.
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Abstract An experiment was carried out to study the effect of soil organic carbon (SOC) and soil texture on the distance of the wetting front, cumulative water infiltration (I), infiltration rate (IR), saturated water conductivity (Ks), and water holding capacity (WHC). Three levels ( 0, 10, 20, and 30 g OC kg-1 ) from organic carbon (OC) were mixed with different soil materials sandy, loam, and clay texture soils. Field capacity (FC) and permanent wilting point (PWP) were estimated. Soil materials were placed in transparent plastic columns(12 cm soil column ), and water infiltration(I) was measured as a function of time, the distance of the wetting front and Ks. Results showed that advance wetting front as a function of time for soil column was 6 minutes and with no differences between OC levels for sandy soils, while it ranged between 90 minutes (0% OC) - 130 minutes (3% OC) for loam soils, and between 470 minutes (0 %OC) and 590 minutes (1%OC) for clay soils, at the same time cumulative water infiltration(I) increases at the beginning of infiltration and decreases with time and levels of OC. The highest infiltration values were in sandy soils, giving data of 0.05 and 0.12 cm min-1, with no significant differences with OC rates. IR values decreased when OC increased in loam soils, and IR increased exponentially in clay soils with increasing OC levels. The values of Ks decrease with increasing OC for sandy and loam soils, and increase when OC increases above 3% for clay soils. FC and WP values were increased for sandy, loam and clay soils when OC was increased. The AW values decreased for both sandy and clay soils compared to loam soils. It can be concluded that AW can be estimated from FC values regardless of texture and OC by the linear function: AW=0.51(FC)+0.005.
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Ridwan, Muhammad, Ade Indra, Annisa Febiana Yunera, and Rudy Kurniawan. "Physical changes of low quality of clay bricks due to sandy-soil mixture under combustion performance." E3S Web of Conferences 331 (2021): 03010. http://dx.doi.org/10.1051/e3sconf/202133103010.
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This research studies the physical properties of the low quality of bricks mixed with sandy -soil in home industries located in Gunung Sarik of Padang City. The ratio mixture of the brick making material in the home industries was not measured with the proper measurement; as a result the quality of the brick was poor. The research used 5 x 5 x 5 cm and 180 cubes of bricks to see the physical changes. The ratio of mixed materials between sandy soil and clay are 0.11.025, 0.43,0.67,1.0, and 1.50. The procedure for making bricks was the same as a factory without changing the factory method. The process of burning bricks for three days and two nights using wood. From the test results, the density of the bricks did not change significantly between direct and indirect fire exposure but decreased in proportion to the addition of sandy soil. The addition of sandy soil reduces the percentage of damage and physical changes. The acceptable ratio of sandy -soil mixture is a range of 0.43.-0.6.
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Fadhil, Roaa M., and Haifaa A. Ali. "Effect of Soaking and Non-soaking Condition on Shear Strength Parameters of Sandy Soil Treated with Additives." Civil Engineering Journal 5, no. 5 (May 21, 2019): 1147–61. http://dx.doi.org/10.28991/cej-2019-03091319.
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The present paper aims to improve shear strength parameters: cohesion (c), and angle of internal friction (∅) for sandy soil treated by additives before and after soaking. The samples of sandy soil were obtained from Karbala city and then classified as poorly graded sand (SP) with relative density Dr (30%) according to the system of (USCS). The experiment has three stages. In the first stage ,the soil was treated with three different percentages of cement (3 ,5 and 7%) of dry weight for the soil with three different percentages of water content (2, 4 and 8%) in each above percentage of cement, while the second stage includes (2%) of lime from soil weight mixed with each different percentage of cement . In the third stage, (50%) of polymer of cement weight was mixed with each different percentage of cement. An analysis of behavior sandy soils treated by additives was carried out with the Direct Shear Tests. All the samples were cured (3) days before and after soaking. The results of the experiment showed that increase in shear strength parameters of sandy soil; especially the angle of internal friction with the rate value (16.6 %) of cement only, (21.88 %) of cement with lime , (20.3%) of cement with the polymer before soaked condition. After soaking condition, it was increased with the rate value (14.3%) with cement only, (23.57%) of cement with lime, and (15.38%) of cement with the polymer as compared with soil in the natural state.
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L. Tsai, K., C. M. Chan, and P. C. Tan. "Compaction and CBR Characteristics of Sandy Clay Stabilised with Fibre-Mixed Binder." International Journal of Engineering & Technology 7, no. 4.14 (December 24, 2019): 343. http://dx.doi.org/10.14419/ijet.v7i4.14.27671.
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Soil chemical stabilization is an effective yet comparatively economical ground improvement method which involves injecting or blending a binder into the existing soil to enhance the geotechnical properties (e.g. strength and stiffness) for load-bearing purposes. The technique is especially beneficial for road construction works on clayey soil of limited load-bearing capacity such as rural roads. It required thick road base is critical to ensure long-term stability and performance. An endeavour is therefore undertaken to examine the effectiveness of a proprietary fibre-mixed binder in stabilizing soils (sandy clay) nature to serve as road base material. Kaolin was mixed with sand as the base soil at ratios of 0, 25 and 50% sand addition. The fibre-mixed binder was added at dosages of 1.5, 2.5 and 3.5% as recommended by the proprietor. Standard compaction test was first carried out to determine the optimum water content for each kaolin-sand mix. Then left to cure for 1, 3, 7 and 28 days before subjected to the California Bearing Ratio (CBR) test. From the test results, it was found that 2.5% binder addition was sufficient to attain the minimum CBR requirement of 30% for supporting a conventional flexible pavement, as per JKR standard. However, the 100% clay sample required higher binder dosages. Clearly sand particles in the soil contributed to the formation of skeletal scaffolding of the soil matrix, bound and supported by the fibre-mixed binder for enhanced strength properties. This was evident in the compaction test where 50% sand addition reduced the optimum water content by almost half compared to the 100% clay. Moreover 3-day curing could adequately strengthen all samples to attain the minimum CBR requirement (JKR standard), irrespective of the binder dosage used. In conclusion, it could effectively strengthen sandy clay soils within 3 days with dosages as low as 2.5%.
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Hussain, Zahid, Tang Cheng, Muhammad Irshad, Riaz Ahmed Khattak, Chen Yao, Di Song, and Muhammad Mohiuddin. "Bentonite clay with different nitrogen sources can effectively reduce nitrate leaching from sandy soil." PLOS ONE 17, no. 12 (December 22, 2022): e0278824. http://dx.doi.org/10.1371/journal.pone.0278824.
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Nitrate (NO3-1) leaching from soils results in the lower soil fertility, reduced crop productivity and increased water pollution. The effects of bentonite clay mixed with various nitrogen (N) fertilizers on NO3-1 leaching from sandy soils haven’t been extensively studied. Therefore, the present lysimetric study determined NO3-1 leaching from bentonite [0, 2 and 4% (m/m)] treated sandy soil under three N sources (calcium nitrate [Ca(NO3)2], ammonium chloride [NH4Cl], and urea [CO(NH2)2] at the rate of 300 kg N ha-1). Results showed that bentonite markedly reduced NO3-1 release in the leachate, while 4% bentonite retained higher NO3 in the soil. The NO3-1 leaching from sandy soil varied with N sources as Ca(NO3)2 > NH4Cl > (CO(NH2)2. At early stages of leaching, higher concentrations of NO3-1 were detected in leachate with both NH4Cl and Ca(NO3)2, but leaching of NO3-1 increased with urea at later leaching stages. The amount of total NO3-1 retained in soil was conversely related to the amount of NO3-1 in the leachate. This study indicated that soil amendment with bentonite could efficiently mitigate NO3-1 leaching from sandy soil and hence prevent N fertilizer losses and groundwater pollution.
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Liu, Yijian, Mengying Yan, Kyungsu Na, Jiho Hwang, Sooan Shin, Lina Yin, Xiping Deng, and Shiwen Wang. "The New Soil Conditioner DewEco Could Improve Sandy Soil’s Properties for Efficient Maize Growth." Agronomy 12, no. 5 (May 6, 2022): 1124. http://dx.doi.org/10.3390/agronomy12051124.
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Sandy soil, one of the most abundant soil types in the world, often has lower crop productivity because of poor water and fertilizer retention capacity. The objective of this study was to investigate the effects of the new soil conditioner DewEco (fermented organic material consisted mainly of salt of L-lysine and citric acid) on sandy soil quality and plant growth. Serial dosages of DewEco and nitrogen (N) fertilizer were mixed into sandy soils and planted maize in a greenhouse. DewEco application increased large soil particle composition and decreased small soil particle composition. Soil porosity and the liquid phase increased as the DewEco dosage increased. DewEco also decreased soil pH and increased soil electrical conductivity, soil organic matter content, total nitrogen and available potassium. DewEco significantly enhanced the soil water-holding capacity and soil effective water content although it also increased the wilting coefficient. Finally, DewEco markedly promoted maize growth while improving water use efficiency (WUE) and nitrogen use efficiency (NUE). In addition, there was an interaction effect between DewEco and nitrogen fertilizer, such that the combined effects of DewEco and N exceeded the sum of their respective effects promoting plant growth. Thus, DewEco application can significantly enhance soil water content and nutrient levels by alleviating sandy soil’s physical and chemical properties, thereby promoting plant growth, WUE and NUE. This study indicates that DewEco is a useful eco-friendly sandy soil conditioner for arid and semi-arid regions.
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El Naggar, Hany, and Ali Iranikhah. "Evaluation of the Shear Strength Behavior of TDA Mixed with Fine and Coarse Aggregates for Backfilling around Buried Structures." Sustainability 13, no. 9 (May 1, 2021): 5087. http://dx.doi.org/10.3390/su13095087.
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Although some discarded tires are reused in various applications, a considerable number end up in landfills, where they pose diverse environmental problems. Waste tires that are shredded to produce tire-derived aggregates (TDA) can be reused in geotechnical engineering applications. Many studies have already been conducted to examine the behavior of pure TDA and soil-TDA mixtures. However, few studies have investigated the behavior of larger TDA particles, 20 to 75 mm in size, mixed with various types of soil at percentages ranging from 0% to 100%. In this study, TDA was mixed with gravelly, sandy, and clayey soils to determine the optimum soil-TDA mixtures for each soil type. A large-scale direct shear box (305 mm × 305 mm × 220 mm) was used, and the mixtures were examined with a series of direct shear tests at confining pressures of 50.1, 98.8, and 196.4 kPa. The test results indicated that the addition of TDA to the considered soils significantly reduces the dry unit weight, making the mixtures attractive for applications requiring lightweight fill materials. It was found that adding TDA to gravel decreases the shear resistance for all considered TDA contents. On the contrary, adding up to 10% TDA by weight to the sandy or clayey soils was found to increase the shear resistance of the mixtures. Adding up to 10% TDA by weight to the clayey soil also sharply increased the angle of internal friction from 18.8° to 32.3°. Moreover, it was also found that the addition of 25% TDA by weight to the gravelly or sandy soils can reduce the lateral earth pressure on buried structures by up to 20%. In comparison, adding 10% TDA to clay resulted in a 36% reduction in the lateral earth pressure.
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Boonraeng, S., and N. Punyoyai. "The utilization of agro-industrial waste for soil amendment and liquid biofertilizer mixed bacterial antagonist in eggplant production." IOP Conference Series: Earth and Environmental Science 883, no. 1 (October 1, 2021): 012087. http://dx.doi.org/10.1088/1755-1315/883/1/012087.
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Abstract This research aimed to improve soil fertility with soil amendment, prepared from agro-industrial waste, and application of antagonistic bacteria for controlling bacterial wilt disease. The experiments were tested on sandy-to-sandy loam soil with low organic matter and nutrients for planting eggplants. Besides the soil improvement with spent mushroom waste and mango peel mixed kernel, the results showed that soil pH, soil organic matter, nitrogen, phosphorus, and potassium increased as available levels. Also, two species of bacterial antagonist named Bacillus subtilis and B. amyloliquifaciens were cultured and mixed in liquid biofertilizer. It was spiked for soil preparation before planting and during crop growth every week, which was affected by eggplant survival from bacterial wilt by 100% and 97% in plot and field-tested, respectively. The results from testing on sandy loam with the use of liquid biofertilizer three times/week showed that Ralstonia solanacearum in soil suppressed to the reduction of 1,000-10,000 times. The yield increased by 25.9%. The optimum harvesting time was 12-15 days of fruit growth with the antioxidant activity. Finally, this study has excellent potential to be extended for farmers who organically grown.
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Nguyen, Trung-Ta, and Petra Marschner. "Addition of a fine-textured soil to compost to reduce nutrient leaching in a sandy soil." Soil Research 51, no. 3 (2013): 232. http://dx.doi.org/10.1071/sr13105.
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Compost addition to soil can increase nutrient availability, but if added to sandy soils, nutrients can be rapidly leached. Clay added to compost could increase nutrient retention and reduce nutrient leaching due to binding to the clay. An incubation experiment was conducted to assess the effect of addition of a fine-textured soil (34% clay) to garden waste compost on nutrient availability and leaching in a sandy soil. The sandy soil was non-amended or amended with compost only, at a rate 27.3 g kg–1, or with a mixture of compost and 5% or 20% (w/w) of fine-textured soil. Two additional treatments included sandy soil amended with only the fine-textured soil at rates similar to those added with compost. Soil, compost, and fine-textured soil were mixed and packed to a bulk density of 1.22 g cm–3. Soil respiration was measured over 23 days. On days 1, 5, and 23, the soils were leached with 50 mL reverse-osmosis water, and the following parameters were measured in the leachate: water-soluble organic carbon (OC), inorganic nitrogen (N), and phosphorus (P); water-soluble OC and available N and P were measured in the soil after leaching. Compost increased nutrient availability and leaching compared with the non-amended control. Addition of the fine-textured soil to compost reduced cumulative respiration and N and P leaching, with the effect more pronounced at 20% (w/w). Addition of the fine-textured soil alone had no effect on nutrient availability and leaching because of the low nutrient concentration in this soil. This study showed that addition of fine-textured soil to compost can reduce N and P leaching, which could enhance and prolong the positive effects of compost on soil fertility.
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Zein El-Abdeen, Hanaa. "Interference between Organic Soil Conditioners Mixed with Synthetic Soil Conditioners to Improve Sandy Soil Productivity." Journal of Soil Sciences and Agricultural Engineering 9, no. 12 (December 1, 2018): 723–34. http://dx.doi.org/10.21608/jssae.2018.36520.
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Jasim, Majeed A., Fatima A. Chyad, and Dina A. Yaseen. "IMPROVEMENT OF SELECTED PARTS OF BASRAH GOVERNORATE SOILS USING A MIXTURE OF CEMENT AND NOVOLAC POLYMER." Kufa Journal of Engineering 5, no. 2 (September 2, 2014): 61–76. http://dx.doi.org/10.30572/2018/kje/521319.
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A weak clayey silt soils from Garmmat Ali and a sandy soil from AL-Nashoa region were used from different sites and depths and mixed with (0.2%,0.4%,0.6 w/W) of Novolac polymer with (2%,4%,6% w/W) of Cement to know the profitable amount of Novolac, and improving some of engineering properties of the soils that include: the plasticity and compacting. A noticeable improvement in the plasticity of these clayey soils as result of adding a mixture by the rise in their plastic limit, dry densities, lowering in their optimum moisture contents, and increase in tensile strengths as compared with crude soils. There are also an improve in treated sandy soil properties. The cost of using this polymer as a soil binder was reduced by about 50% as compared to the usual practice which involve removing the clayey silt soils and replace them by sand or other materials.
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Adams, Jason W., and Rodney G. Lym. "Quinclorac and Aminocyclopyrachlor Movement in Sandy Soils." Invasive Plant Science and Management 8, no. 3 (September 2015): 269–75. http://dx.doi.org/10.1614/ipsm-d-14-00070.1.
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AbstractThe Sheyenne National Grassland (SNG) is a native tall grass and mixed grass prairie located in southeastern North Dakota. Approximately half of the SNG has been invaded by leafy spurge (Euphorbia esulaL.) and control methods have been limited. Many herbicides cannot be utilized at the SNG due to sandy soils (> 80%) and shallow groundwater, nor can they be applied near the western prairie fringed orchid (Platanthera praeclaraSheviak and Bowles), a federally listed threatened plant found on the SNG. Quinclorac and aminocyclopyrachlor were considered for use on the SNG but potential to enter the groundwater was unclear. Movement of quinclorac and aminocyclopyrachlor was evaluated in 70 cm soil columns that simulated field conditions from five ecological sites. Quinclorac leached further following the heavy rainfall event of 15 cm in 48 h compared to the annual precipitation of 51 cm applied over 9 wk. Quinclorac leached approximately 45 cm into the soil profile averaged over all soil types and both precipitation events but never exceeded 65 cm regardless of soil type. Aminocyclopyrachlor leaching was greater than quinclorac and moved through all soil types into the leachate following both watering regimes. Desorption of both herbicides was incomplete. Approximately 10 and 32% of applied aminocyclopyrachlor and quinclorac, respectively, remained in the top 5 cm of soil regardless of soil type or watering regime. Quinclorac but not aminocyclopyrachlor was considered suitable for use at the SNG to control leafy spurge and has the added benefit of not harming the western prairie fringed orchid.
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Saakian, Alexander. "Soil successions of carbic podzols (arenic) and umbric podzolsof sand forest steppe at change of forest-forming rocks." АгроЭкоИнфо 2, no. 44 (April 2, 2021): 13. http://dx.doi.org/10.51419/20212213.
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The article presents the data of ecological-soil survey of carbic podzols (aerenic) and umbric podzols of sandy pine forests of the Kursk agglomeration. The data on the transformation of morphological, physical and physicochemical properties of the studied soils in the succession series "pine forest - mixed forest - broadleaf forest" are presented. It has been established that when the monodominant plantations of Scots pine are replaced by deciduous species, the soil-forming processes change - podzolic to sod. The settling of deciduous species in pine plantations gradually leads to attenuation of the podzolic process, the development of processes of accumulation of humus and mineral nutrients in the soil profile, which contributes to an increase in the ecological stability of azonal carbic podzols (aerenic) and sandy umbric podzols in the conditions of the forest-steppe zone. Keywords: MICROEVOLUTION OF SOILS, TERRACE ABOVE FLOOD-PLAIN, PODZOLY PROCESS, SODDY PROCESS, SOIL SUCCESSION
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Ateş, Ali. "The Effect of Polymer-Cement Stabilization on the Unconfined Compressive Strength of Liquefiable Soils." International Journal of Polymer Science 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/356214.
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Soil stabilization has been widely used as an alternative to substitute the lack of suitable material on site. The use of nontraditional chemical stabilizers in soil improvement is growing daily. In this study a laboratory experiment was conducted to evaluate the effects of waterborne polymer on unconfined compression strength and to study the effect of cement grout on pre-venting of liquefiable sandy soils. The laboratory tests were performed including grain size of sandy soil, unit weight, ultrasonic pulse velocity, and unconfined compressive strength test. The sand and various amounts of polymer (1%, 2%, 3%, and 4%) and cement (10%, 20%, 30%, and 40%) were mixed with all of them into dough using mechanical kneader in laboratory conditions. Grouting experiment is performed with a cylindrical mould of mm. The samples were subjected to unconfined compression tests to determine their strength after 7 and 14 days of curing. The results of the tests indicated that the waterborne polymer significantly improved the unconfined compression strength of sandy soils which have susceptibility of liquefaction.
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Bengough, A. Glyn, Roy Neilson, Bryan Griffiths, and David Trudgill. "The extent to which nematode communities are affected by soil factors-a pot experiment." Nematology 4, no. 8 (2002): 943–52. http://dx.doi.org/10.1163/156854102321122566.
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AbstractFour similar, agricultural soils with distinct nematode communities were used to determine the extent to which soil and inoculum factors affected nematode community structure. The soils all had a sandy loam texture from the same geographical area and had been in pasture or arable rotation for the last 10 years. Treatments were established in pots containing a middle layer of frozen defaunated soil, sandwiched between an inoculum that was either fresh soil from the same site ('self') or a mixture of soils to give a more diverse inoculum ('mixed'). Principal component analysis indicated that a single soil type given different inocula developed different community structures (i.e., the community under 'self' differed from that under 'mixed') suggesting an inoculum effect. It was also true that different soil types under a single inoculum soil also developed different community structures (i.e., community under 'mixed' differed with soil type), suggesting a soil effect. It is likely that the nematode community structure is influenced by a combination of antecedent land use, soil factors, species introductions and inter-species competition, which should be considered in any interpretation of nematode communities as a biotic indicator.
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Qiu, Shi, Hao Hu, Jun Peng Liu, Xiang Hui Lv, Xiang Li Wang, and Wen Jie Li. "A Kind of Land Form Detector for Loose and Soft Sandy Soil Milling-Planing and Collecting Device Machinery." Advanced Materials Research 328-330 (September 2011): 1772–77. http://dx.doi.org/10.4028/www.scientific.net/amr.328-330.1772.
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In a Certain Mining Engineering, it’s Needed to Collect the Ore Bearing Sandy Soil with Certain Thickness from the Ground Surface. in Order to Realize Accurate Collection, it’s Needed to Control the Collecting Thickness Strictly. the Application of Contacting Type Landform Detecting Method in the Engineering Machinery Was Discussed, and a Kind of Mechanical Contacting Landform Detector Was Developed for the Alluvium Landform of Mining Area in Gobi with Loose, Rough and Uneven Ground Surface. the Landform of Soft Sandy Soil Can Be Detected by Controlling the Contact Pressure between the Depth Wheel of the Detector and the Ground Surface. with the Use of PID Control Technology with Wave Filtering, the Real-Time Detection Accuracy of the Detector for Mixed Sandy Soil Ground Surface Reaches ± 3mm. this Detector Is Specially Used for Milling, Planing and Collecting Device, Achieving Uniform Thickness Collection of Ore Bearing Sandy Soil in Rolling Topography Condition.
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Zhang, Zhiwei, Beibei Liu, Zhenli He, Pan Pan, Lin Wu, Bigui Lin, Qinfen Li, Xinchun Zhang, and Zhikang Wang. "The Synergistic Effect of Biochar-Combined Activated Phosphate Rock Treatments in Typical Vegetables in Tropical Sandy Soil: Results from Nutrition Supply and the Immobilization of Toxic Metals." International Journal of Environmental Research and Public Health 19, no. 11 (May 25, 2022): 6431. http://dx.doi.org/10.3390/ijerph19116431.
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Sandy soils in tropical areas are more vulnerable to potential toxic elements as a result of their low nutrition. The composite addition of biochar and phosphate material is considered a promising method of immobilizing toxic metals in sandy soils, but the synergistic effects of this process still need to be further explored, especially in typical tropical vegetables. In this study, a pot experiment was conducted to evaluate the agronomic and toxic metal-immobilization effects of single amendments (phosphate rock, activated phosphate rock, and biochar) and combined amendments, including biochar mixed with phosphate rock (BCPR) and biochar mixed with activated phosphate rock (BCAPR), on vegetables grown in tropical sandy soil. Among these amendments, the composite amendment BCAPR was the most effective for increasing Ca, Mg, and P uptake based on water spinach (Ipomoea aquatica L.) and pepper (Capsicum annuum L.), showing increased ratios of 22.5%, 146.0%, and 136.0%, respectively. The SEM-EDS and FTIR analysis verified that the activation process induced by humic acid resulted in the complexation and chelation of the elements P, Ca, and Mg into bioavailable forms. Furthermore, the retention of available nutrition elements was enhanced due to the strong adsorption capacity of the biochar. In terms of cadmium (Cd) and lead (Pb) passivation, the formation of insoluble mineral precipitates reduced the mobility of these metals within the BCAPR treatments, with the maximum level of extractable Cd (86.6%) and Pb (39.2%) reduction being observed in the tropical sandy soil. These results explore the use of sustainable novel cost-effective and highly efficient bi-functional mineral-based soil amendments for metal passivation and plant protection.
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Balah, Mohammed A., Sayed A. Dahroug, Zidane H. Zidan, and Abdel-Rahman Gamal Aldin. "Effect of some Additives on the hydrolysis, persistence and the downward Movement of Glyphosate and Fluazifop-butyl Herbicides." Al-Mukhtar Journal of Sciences 32, no. 2 (December 31, 2017): 102–10. http://dx.doi.org/10.54172/mjsc.v32i2.152.
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The first objective was to determine the effect of additives and water type on the degradation of glyphosate and fluazifop-butyl herbicides. Both glyphosate and fusillade were strongly hydrolysed in hard water more than Nile water and distilled water. Most additives were decreased glyphosate persistence in all types of water. Glyphosate plus glue was more persistent than glyphosate alone and when mixed with the following additives (urea, glycerine, dioleate, monoleate, paraffin and mineral oil), respectively. Fusilade alone was more persistent than its mixture with the additives rape seed oil, mineral oil, paraffin oil, dioleate and monoleate, respectively. The second objective was to deal with the effect of additives soil texture interactions on persistance and leaching of glyphosate and fluazifop-butyl herbicides. Persistence of glyphosate in clay soil was lower than in sandy soil. Most additives increased half life of glyphosate in clay soil, while glyphosate additive mixtures decreased its stability in sandy soil. Fluazifop-butyl was rapidly dissipated in clay soil more than the sandy soil. Whereas most of the used adjuvant decreased fluazifop-butyl half life in each soil. Glyphosate was not detected in the soil leachate of clay and sandy soil column. The majority of glyphosate and fluazifop-butyl amount was located in the top layer of soil column followed by fewer amounts in the successive layers. Whereas glyphosate and fluazifop-butyl could be transferred from the sub- surface to the following layer from sandy soil with some additives (surfactants) to the following layer. Meanwhile fusillade with surfactants was detected in sandy soil column leaching with non significant amount.
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Guo, Zhen, Haiou Zhang, Juan Li, Tianqing Chen, Huanyuan Wang, and Yang Zhang. "Distribution of soil microorganisms in different complex soil layers in Mu Us sandy land." PLOS ONE 18, no. 4 (April 7, 2023): e0283341. http://dx.doi.org/10.1371/journal.pone.0283341.
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The soft rock in Mu Us Sandy Land has rich resources and high content of clay minerals. The combination of soft rock with sand can play a certain role in sand fixation and promote the green development of ecological environment. In this paper, the aeolian sandy soil in Mu Us Sandy was taken as the research object, and it was mixed with soft rock to form composite soil. The four volume ratios of soft rock to sand were respectively 0:1, 1:5, 1:2 and 1:1. And CK, P1, P2 and P3 were used to represent the above four volume ratios in turn. By means of quantitative fluorescent PCR and high throughput sequencing, 16S rRNA gene abundance and community structure were investigated. The results showed that the soil organic carbon (SOC) and total nitrogen (TN) contents in 0-30cm soil layer were higher. Compared with CK, the SOC of P2 was improved by 112.77% and that of P1 was 88.67%. The content of available phosphorus (AP) and available potassium (AK) was higher in 30-60cm soil layer, and P3 was more effective. The abundance of 16S rRNA gene in the mixed soil bacteria ranged from 0.03×109 to 0.21×109 copies g-1 dry soil, which was consistent with the changes of nutrients. Under different soil layers, the three dominant bacteria in the mixed soil were the same, namely Phylum Actinobacteriota, Phylum Proteobacteria and Phylum Chloroflexi, and there were more unique genera in each soil layer. Both bacteria ɑ and β diversity showed that the community structure of P1 and P3 in 0-30cm soil layers was similar, and that of P1 and P2 in 30-60cm soil layers was similar. AK, SOC, AN (ammonium nitrogen), TN and NN (nitrate nitrogen) were the main factors contributing to the differentiation of microbial community structure under different compound ratios and soil layers, and Phylum Actinobacteria has the largest correlation with nutrients. The results showed that the soft rock could improve the quality of sandy soil, and that the growth of microbial growth was dependent on the soil physicochemical characteristics. The results of this study will be helpful to the study of the microscopical theory for the control of the wind-blown sand and the ecology of the desert.
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Kudakwashe Hove, Justina Johannes, Gervasius Hatutale, Simon Kamwele Awala, and Petrus Ausiku. "Growth and yield response of Swiss chard (Beta vulgaris (L.) to media mixture ratios of sand, acacia soil, and goat manure." Magna Scientia Advanced Biology and Pharmacy 1, no. 1 (November 30, 2020): 018–24. http://dx.doi.org/10.30574/msabp.2020.1.1.0015.
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Northern Namibian soils are predominantly sandy. A mixture of Acacia soils, sandy and goat manure is frequently used for growing various plants. However, the extent to which variations in proportions of these substrates affect growth and yield is not known. The study was conducted at the University of Namibia, Ogongo campus during the period April to August 2020 to determine optimum mixing ratios for sandy, Acacia erioloba soil and goat manure on the growth and yield of Swiss chard. Treatments were Sandy, Acacia soil and goat manure mixed in 5 different ratios of respectively; 1:2:1; 2:3:2; 1:1:1, 2:1:2, 1:1:2 and Acacia soil (control). Samples from each mixture used for pot filling were taken to the soil laboratory for textural analysis. A complete randomized experiment with 8 replications was laid under the University’s shade house. Measured parameters were plant height, leaf area, fresh and dry matter weight and chlorophyll content. Results showed that media was significantly different across all the measured parameters at 1 % probability level. The medium mixture 2:3:2 outperformed the rest of the mixtures in almost all the parameters. The results of the study indicated that acacia soil alone is not optimum for pot filling but must be supplemented with substrate that is rich in mineral content like goat manure. However, the mixing ratio is a key consideration for optimal vegetable production. We recommend the use of media mixture 2:3:2 to improve yield of Swiss chard.
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TRYDEMAN KNUDSEN, M., H. HAUGGAARD-NIELSEN, B. JØRNSGÅRD, and E. STEEN JENSEN. "Comparison of interspecific competition and N use in pea–barley, faba bean–barley and lupin–barley intercrops grown at two temperate locations." Journal of Agricultural Science 142, no. 6 (December 2004): 617–27. http://dx.doi.org/10.1017/s0021859604004745.
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Mixed intercropping of spring barley (Hordeum vulgare L.) with field pea (Pisum sativum L.), faba bean (Vicia faba var. minor L.) or narrow-leafed lupin (Lupinus angustifolius L.) was compared with sole cropping in two field experiments at different locations, on a sandy loam soil and a sandy soil, in Denmark in 2001.Grain legumes were dominant in intercrops on the sandy loam soil, except for lupin, whereas barley was dominant in intercrops on the sandy soil site. Combined intercrop grain yields were comparable to grain yields of the respective sole cropped grain legume or sole cropped, fertilized barley on each soil site. On the sandy loam soil, pea–barley and faba bean–barley intercrops increased the proportion of plant N derived from N2 fixation in grain legumes and increased the barley grain N concentration (from 1·7 to 2·2 mg/g) compared with sole cropping. However, the later maturity of faba bean compared with barley caused problems at harvest. The grain N concentration of intercropped barley was increased where grain legumes were the dominant intercrops and not on the sandy soil site. Lupin-barley intercrops did not show intercropping advantages to the same degree as faba bean and pea, but lupin constituted a more stable yield proportion of the combined intercrop yield over locations.Furthermore, the study indicated that the natural 15N abundance at certain locations might not always be sufficient to ensure a reliable estimate of N2 fixation using the 15N natural abundance method.
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Sulakhudin, Sulakhudin, Abdul Syukur, Dja'far Shiddieq, and Triwibowo Yuwono. "Effect of Coated Urea with Humic-Calcium on Transformation of Nitrogen in Coastal Sandy Soil: A Soil Column Method." JOURNAL OF TROPICAL SOILS 15, no. 1 (April 9, 2018): 11. http://dx.doi.org/10.5400/jts.2010.v15i1.11-18.
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Effect of Coated Urea with Humic-Calcium on Transformation of Nitrogen in Coastal Sandy Soil: A Soil Column Method (Sulakhudin, A Syukur, D Shiddieq and T Yuwono): In coastal sandy soil, mainly nitrogen losses due to leaching resulted to low fertilizer efficiency. Slow-release N fertilizers are proposed to minimize these losses, and humic-calcium coated urea has been examined. A soil column method was used to compare the effects of coated urea with humic-calcium on transformation and leaching loss of N in coastal sandy soil. The experiment aid to compare two kind source humic substances (cow manure and peat) which mixed with calcium as coated urea on transformation, vertical distribution and leaching N in coastal sandy soil. The concentration of humic-calcium coated urea i.e.1%, 5% and 10% based on their weight. The results showed that urea coated with humic-calcium from cow manure (UCHM) and humic-calcium from peat (UCHP) increased the N total and available N in the soil and decreased leaching loss of N from the soil column. Compare to UCHP, UCHM in all concentration showed N-nitrate higher than N-ammonium on incubation length 2, 4 and 6 weeks. The N leached from a costal sandy soil with application coated urea with UCHM ranged from 21.18% to 23.72% of the total N added as fertilizer, for coated urea with UCHP they ranged between 21.44% and 23.25%, whereas for urea (control) reach 29.48%. Leaching losses of mineral N were lower when urea coated with UCHM compared to urea coated with UCHP or urea fertilizer. The study concluded that the UCHM is better than UCHP in decreasing N leached from coastal sandy soil.
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Li, Yi, Junjun Wu, Bo Zhong, Xiaoliang Shi, Kunpeng Xu, Kai Ao, Bin Sun, et al. "Methods of Sandy Land Detection in a Sparse-Vegetation Scene Based on the Fusion of HJ-2A Hyperspectral and GF-3 SAR Data." Remote Sensing 14, no. 5 (March 1, 2022): 1203. http://dx.doi.org/10.3390/rs14051203.
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Accurate identification of sandy land plays an important role in sandy land prevention and control. It is difficult to identify the nature of sandy land due to vegetation covering the soil in the sandy area. Therefore, HJ-2A hyperspectral data and GF-3 Synthetic Aperture Radar (SAR) data were used as the main data sources in this article. The advantages of the spectral characteristics of a hyperspectral image and the penetration characteristics of SAR data were used synthetically to carry out mixed-pixel decomposition in the “horizontal” direction and polarization decomposition in the “vertical” direction. The results showed that in the study area of the Otingdag Sandy Land, in China, the accuracy of sandy land detection based on feature-level fusion and single GF-3 data was verified to be 92% in both cases by field data; the accuracy of sandy land detection based on feature-level fusion was verified to be 88.74% by the data collected from Google high-resolution imagery, which was higher than that based on single HJ-2A (74.17%) and single GF-3 data (88.08%). To further verify the universality of the feature-level fusion method for sandy land detection, Alxa sandy land was also used as a verification area and the accuracy of sandy land detection was verified to be as high as 88.74%. The method proposed in this paper made full use of the horizontal and vertical structural information of remote sensing data. The problem of mixed pixels in sparse-vegetation scenes in the horizontal direction and the problem of vegetation covering sandy soil in the vertical direction were both well solved. Accurate identification of sandy land can be realized effectively, which can provide technical support for sandy land prevention and control.
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Verma, R. K., D. V. Yadav, C. P. Singh, A. Suman, and A. Gaur. "Effect of heavy metals on soil respiration during decomposition of sugarcane (Saccharum officinarum L.) trash in different soils." Plant, Soil and Environment 56, No. 2 (February 26, 2010): 76–81. http://dx.doi.org/10.17221/1773-pse.
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An experiment was conducted to study the effect of heavy metals (Cd, Cr and Pb), soil texture (sandy, loam and clay) and incubation periods (7, 15, 30, 60, 90 and 120 days) on soil respiration (CO<sub>2</sub> evolution) during sugarcane trash decomposition in laboratory conditions of the Indian Institute of Sugarcane Research, Lucknow, India. Surface soils (0–15 cm) were collected from agricultural fields and crop residue of sugarcane trash (<i>Saccharum officinarum</i> L.) was taken in the institute farm. Crop residue (10 t/ha) and heavy metals (10, 50, 100, 1000 μg/g) were mixed and incubated at 30°C ± 2°C in an incubator. The rate of soil respiration (CO<sub>2</sub> evolution) decreased with increasing heavy metals concentration. During the 120 days, the toxicity decreased but still remained significant. Maximum soil respiration was recorded at 7 days of incubation period; further, it decreased with increasing incubation period. The highest drop of soil respiration rate was caused by addition of 1000 μg/g Cd, Cr and Pb levels. Clay soils evolved maximum CO<sub>2</sub> followed by loam and sandy soil.
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Ćwieląg-Piasecka, Irmina, Magdalena Debicka, and Agnieszka Medyńska-Juraszek. "Effectiveness of Carbaryl, Carbofuran and Metolachlor Retention in Soils under the Influence of Different Colloid." Minerals 11, no. 9 (August 26, 2021): 924. http://dx.doi.org/10.3390/min11090924.
Full textAbstract:
The affinity of different soil colloids to retain carbaryl, carbofuran and metolachlor in sandy loam and loam soil from mineral, surface horizons was investigated. The undisturbed soil samples and soils amended with colloids—kaolinite (K), montmorillonite (Mt), illite (Il), goethite (G), humic acid (HA)—were mixed with the pesticides for sorption–desorption studies. Their sorption magnitude in pristine soils followed the sequence metolachlor > carbaryl > carbofuran, with loam soil being a better pesticides retarder than sandy soil. The biggest magnitude of carbaryl sorption in light soil was observed in samples with the addition of HA (92.7%), Il (92.3%) and Ge (87.5%), whereas for carbofuran it was goethite (52.3%). Metolachlor uptake was significantly enhanced by 2:1 clays (Mt-85.0%, Il-69.4%), goethite (73.3%) and humic acids (75.4%). The loamy soil sorption capacity of the studied pesticides was blocked by the natural organic matter potentially due to the formation of organo-mineral complexes. HA (66.8%) was the most effective sorbent for carbaryl in the loamy soil, whereas Mt (55.1%) and HA (40.3%) for carbofuran. Metolachlor was retained to the same extent in all loamy soil variants (75.8–83.6%) and its desorption values were the lowest. Carbofuran demonstrated the greatest ability to leach among the studied chemicals.
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Lu, Weihua, Linchang Miao, Junhui Zhang, Yongxing Zhang, and Jing Li. "Characteristics of Deformation and Damping of Cement Treated and Expanded Polystyrene Mixed Lightweight Subgrade Fill under Cyclic Load." Applied Sciences 9, no. 1 (January 4, 2019): 167. http://dx.doi.org/10.3390/app9010167.
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To investigate the deformation and damping characteristics of cement treated and expanded polystyrene (EPS) beads mixed lightweight soils, this study conducted a series of triaxial shear tests cyclic loading for different confining pressures, cement contents, and soil categories. Through repeated loading and unloading cycles, axial accumulative strain, resilient modulus, and damping ratio versus axial total strain were analyzed and the mechanical behavior was revealed and interpreted. Results show that the resilient modulus increases with increasing confining pressure and cement content. A decreasing power function can be used to fit the relationship between the resilient modulus and the axial total strain. Although sandy lightweight specimens usually own higher resilient modulus than silty clay lightweight specimens do, the opposite was also found when the axial total strain is larger than 8% with 50 kPa confining pressure and 14% cement content. For damping ratio the EPS beads mixed lightweight soil yields a weak growth trend with increasing axial total strain and a small reduction with higher confining pressure and cement content. For more cementations, the damping ratio of the sandy lightweight soil is always smaller than the silty clay lightweight soil. Nonetheless, the differences of damping ratios that were obtained under all of the test conditions are not significant.
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Sloan*, John, and Wayne Mackay. "Increased Water Use Efficiency with a Surfactant." HortScience 39, no. 4 (July 2004): 763B—763. http://dx.doi.org/10.21273/hortsci.39.4.763b.
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Soils exhibit a degree of hydrophobicity and can repel water rather than absorb it. Surfactants lower the surface tension of water which may increase its infiltration into the soil and adsorption to soil solids. The objective of this study was to determine if water treated with a surfactant would increase conserve soil moisture and decrease the amount of water needed to sustain healthy plant growth. Clay and sandy loam soils were placed in 15-cm greenhouse pots. Impatiens seedlings were transplanted into each pot. All pots were fertilized equally and the Impatiens flowers were allowed to grow for 8 weeks. Then the pots were treated with tap water or tap water mixed with a commercial surfactant at one times (1×) or two times (2×) the recommended rate. After applying the water treatments, pots received no additional water. Each pot was weighed twice per day and the plants were observed for signs of wilting. Upon initial signs of wilting, each plant was rated on a scale of 1 to 3 with 1 = no wilting, 2 = leaves starting to droop, and 3 = wilting leaves and stems. Addition of the surfactant at the 1× and 2× rates slowed the loss of water from both the sandy loam and the clay soils. The effects of the surfactant were apparent within 3 to 5 days in the sandy loam soil and 6 to 10 days in the clay soil. The benefits of reduced water loss from soil were manifested by reduced wilting in Impatiens plants in soils treated with 1× and 2× the recommended rate of surfactant. In the clay soil, use of the surfactant increased the amount of time before Impatiens plants began to wilt. It appears that adding a surfactant to irrigation water can conserve soil moisture and extend the time between water applications.
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S. S. AL- Wali, Nuhad, and Kawthar A. AL- Mosawi. "A Study of Some Physical Properties of Two Different Soil Textures Planted with Conocarpus Trees (Conocarpuslancifolius. Engl)." Al-Qadisiyah Journal For Agriculture Sciences (QJAS) (P-ISSN: 2077-5822 , E-ISSN: 2617-1479) 7, no. 2 (April 14, 2018): 133–45. http://dx.doi.org/10.33794/qjas.vol7.iss2.35.
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This research has been conducted to study the effect of Conocarpus trees and their roots on some of soilphysical properties. The soil physical properties are moisture content , bulk density , total porosity , mean weight diameter (dry sieveing) and soil penetration resistance . Some soil samples are collected from two locations :the first location is Agric. College research, Garmat Ali, stations , Basra university , and the second location isZuwber province farm . The soil texture of the first location is silty clay which is classified as fine clay mixed Calcarioushy perthermictypictorrifluvent, while the soil texture of the second location is sandy loam. This soil is classified with in species Entisol and under species psamments and high group , underhigh group and family (Typictorripsamments, Calcarious Mixed Hyperthermic). The soil samples are collected from two soil depths( 0 – 30 and 30 – 60) from both locations are planted with Conocarpus trees, their ages ranged between 4 to 5 years . The trees height is 2.5 – 3.0 m . Another soil samples are also collected from unplanted soil with Conocarpus trees. The results reveated that the silty clay soil is significantly surpassed the sandy loam soil in moisture content and mean weight diameter by a percentage of 68.76% and 32.91% respectively . Whereas, the bulk density and soil penetration resistance decreased , while the total porosity of the silty clay soil as compared with sandy loam soil .For unplanted soil, moisture content, the bulk density and the soil penetration resistance are increased as compared with planted soil . The soil depth (30 – 60)cm is surpassed soil depth of ( 0- 30)cm in giving higher values of moisture content andbulk density whereas it does not significantly affect the mean weight diameter and soil penetration resistance .
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Yang, Kai, Zejun Tang, and Jianzhang Feng. "Effect of Co-Use of Fly Ash and Granular Polyacrylamide on Infiltration, Runoff, and Sediment Yield from Sandy Soil under Simulated Rainfall." Agronomy 10, no. 3 (March 3, 2020): 344. http://dx.doi.org/10.3390/agronomy10030344.
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Coal fly ash (FA) and polyacrylamide (PAM) are two common amendments for improving hydraulic properties of sandy soil. However, their interaction effect on infiltration-runoff processes in sandy soil has been scarcely reported. In this study, FA and anionic PAM granules were mixed thoroughly with a 0–0.2 m sandy soil layer at FA rates of 0%, 10%, and 15% (w/w soil), and PAM rates of 0%, 0.01%, and 0.02% (w/w soil) along with each FA rate. A simulated rainfall laboratory experiment (slope gradient of 10°, rainfall intensity of 1.5 mm/min) was conducted. During the rainfall, the cumulative runoff yield increased while the average infiltration rate decreased with increasing FA and PAM rates. A higher FA rate of 15% and varying PAM rates resulted in a prominent increase in cumulative sediment yield. After the rainfall, the two-dimensional distribution of water content retained in the soil profile reflected that both FA and PAM increased the water retention capacity of sandy soil, and the effect became more obvious at higher FA and PAM rates. The possible mechanism for the effect of FA and PAM on inhibiting water infiltration during the rainfall and retaining water in the soil layer after the rainfall is attributed to the filling of pores of the coarse soil particles by fine-sized FA particles and flocculation function and binding action of PAM.
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Choudhary, M. I., A. M. AI-Omran, and A. A. Shalaby. "Physical Properties of Sandy Soil Affected by Soil Conditioner Under Wetting and Drying cycles." Journal of Agricultural and Marine Sciences [JAMS] 3, no. 2 (June 1, 1998): 69. http://dx.doi.org/10.24200/jams.vol3iss2pp69-74.
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Information on the effectiveness of soil conditioners over a prolonged period is scarce. A laboratory experiment was undertaken to evaluate the effectiveness of a polyacrylamide (Broadleaf P4) soil conditioner on the physical properties of sandy soil subjected to wetting and drying cycles. Four concentrations of Broadleaf P4 0, 0.2, 0.4, and 0.6% on dry weight basis were uniformly mixed with a calcareous sandy soil. Addition of Broadleaf P4 to sandy soil increased the water holding capacity, decreased the bulk density, and increased the porosity and void ratio at 0 and 16 wetting and drying cycles. The coefficient of linear extensibility increased considerably with increasing concentrations of the polymer. The addition of polymer at 0 and 16 cycles increased considerably the retention and availability of water in sandy soil. Saturated hydraulic conductivity decreased with increasing concentrations of Broadleaf P4 whereas unsaturated hydraulic conductivity at 0 and 16 cycles showed an increase with increasing soil moisture contents. After I6 wetting and drying cycles, the capacity of the soil to hold water was lost on average by 15.8% when compared to the 0 wetting and drying cycle. The effectiveness of the soil conditioner on bulk density, coefficient of linear extensibility, available water and saturated hydraulic conductivity was reduced on average by 14.1, 24.5, 21.l and 53.7% respectively. The significant changes in soil properties between 0 and 16 cycles suggested that the effectiveness of the conditioner decreased with the application of wetting and drying cycles. However, its effect was still considerable when compared to untreated soil under laboratory conditions.
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Akhter, J., K. Mahmood, K. A. Malik, A. Mardan, M. Ahmad, and M. M. Iqbal. "Effects of hydrogel amendment on water storage of sandy loam and loam soils and seedling growth of barley, wheat and chickpea." Plant, Soil and Environment 50, No. 10 (December 10, 2011): 463–69. http://dx.doi.org/10.17221/4059-pse.
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The hydrogel amendments may improve seedling growth and establishment by increasing water retention capacity of soils and regulating the plants available water supplies, particularly under arid environments. The effects of different levels of a locally prepared hydrogel were studied on the moisture properties of sandy loam and loam soils (fine-loamy, mixed, hyperthermic Typic Haplargids, USDA, Luvic Yermosol, FAO) and on growth response of three plant species, viz. barley (Hordeum vulgare L.), wheat (Triticum aestivum L.) and chickpea (Cicer arietinum L.). Water absorption by gel was rapid and highest in distilled water and was inhibited by an increase in water salinity. The addition of 0.1, 0.2 and 0.3% hydrogel increased the moisture retention (θr) at field capacity linearly (r = 0.988) and thus the amount of plant available water significantly in both sandy loam and loam soils compared to the untreated soils. Seed germination of wheat and barley was not affected but seedling growth of both species was improved by the gel amendment. In loam soil, seed germination of chickpea was higher with 0.2% gel and seedling growth increased with increase in gel level compared with control conditions. The hydrogel amendment caused a delay by 4–5 days in wilting of seedlings grown in both soils compared with control conditions. The hydrogel amendment was effective in improving soil moisture availability and thus increased plant establishment. However, the varied responses of plant species in sandy loam and loam soils warrant further studies on the behaviour of different soil types with gel amendments.
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Milad, Ramadan A., Mostafa A. Benzaghta, and Mahmoud A. Amaref. "The effect of reusing treated wastewater in irrigation on some chemical soil properties and wheat crop growth." Journal of Misurata University for Agricultural Sciences, no. 01 (October 6, 2019): 196–208. http://dx.doi.org/10.36602/jmuas.2019.v01.01.15.
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This study was aimed to investigate the suitability of reusing of treated wastewater to irrigate wheat crop and its impact on soil properties. The study was conducted during the Agricultural season 2014-2015, at Sirte, Libya. The climate of this area characterized by dry and hot in summer, cool and rained in winter, as well as the annual rainfall in the range of 175 mm to 200 mm, so the area is considered as semi-arid area. The experiment was designed to use treated wastewater under different managements ((W1) 100% fresh water (from artificial stream), (W2) Mixed by 50% fresh water and treated wastewater, (W3) mixed by 33% fresh water and 67% treated wastewater and (W4) 100% treated wastewater). Two soil profiles were selected and described, namely Sandy (S1) and Sandy loam (S2) soils. Wheat crop was used as indicator. The chemical, physical and microbiological analyses were done for water and soil samples using standard methods. The analyses include soil texture, bulk density, moisture content, electrical conductivity, pH, anions, cations, and E coli form. Also, the wheat crop growth components were studied. The quality of used water was found within the permissible levels of the Food and Agricultural Organization of the United Nation (FAO) for irrigation water, while lead was found exceeding the sever permissible level. From the other hand treated wastewater showed significant difference at P≤0.05 in increasing the average values of wheat crop growth components, in compare with fresh water, which recorded the lowest values. The chemical properties of soils extractions showed non -significant difference at P≤0.05 under the different irrigation managements, while the chloride and lead showed significant increase in sand loamy soil and carbonate in sandy soil. On the other hand, the both soils showed the same performance in increasing wheat growth components. The treated wastewater (W4) supplied significant numbers of E coli form 100/ml to the both soils followed by (W3), while fresh water recorded less values. The study concluded that using of treated wastewater in irrigation of agricultural crops under monitoring system has economic feasibility.
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Castelli, Francesco, Antonio Cavallaro, Salvatore Grasso, and Valentina Lentini. "Undrained Cyclic Laboratory Behavior of Sandy Soils." Geosciences 9, no. 12 (December 11, 2019): 512. http://dx.doi.org/10.3390/geosciences9120512.
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The complex cyclic shear stress path experienced by the soil during an earthquake, which could also induce liquefaction phenomena, can be approximated in the laboratory only by using sophisticated testing apparatuses. Cyclic triaxial tests have been widely used, especially for coarse grained soils, as in this study. In the framework of the design for the seismic retrofitting of the ‘‘Ritiro viaduct’’ foundations along the A20 motorway connecting Messina with Palermo (Italy), a soil liquefaction study was also carried out. With this aim, a detailed geological and geotechnical characterization of the area was performed by in situ and laboratory tests, including seismic dilatometer Marchetti tests (SDMTs), the combined resonant column (RCT) and cyclic loading torsional shear tests (CLTSTs), and undrained cyclic loading triaxial tests (CLTxTs). In particular, the paper presents the results of cyclic triaxial tests carried out on isotropically consolidated specimens of a sandy soil. The seismic retrofitting works include the reinforcement of the foundation and replacement of the decks with newly designed type and structural schemes, mixed steel, and concrete with continuous girder. During the investigation, data were acquired for the characterization of materials, for the definition of degradation phenomena with the relative identification of possible causes, and for the estimation of the residual performance characteristics of the building. The structural campaign of investigations necessary to determine all of the key parameters useful for a correct definition of the residual performance capabilities of the work was divided into two phases: One in situ and one in the laboratory.
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Ayeni, Albert O., Bradley A. Majek, and Jeff Hammerstedt. "Rainfall influence on imazethapyr bioactivity in New Jersey soils." Weed Science 46, no. 5 (October 1998): 581–86. http://dx.doi.org/10.1017/s004317450009113x.
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Greenhouse studies were conducted with soil columns to determine the influence of rainfall amount, intensity, and time of application on the bioactivity of 0.07 kg ae ha−1imazethapyr in three soils of New Jersey: the Berryland sand (BLS) (sandy, siliceous, mesic Typic Haplaquod), Aura sandy loam (ASL) (mixed, mesic Typic Hapludult), and Quakertown silt loam (QSIL) (mixed, mesic Typic Hapludult). The Brockman-Duke simulated rainfall machine was used for rainfall application and smooth pigweed as an imazethapyr bioactivity indicator. As rainfall amount increased from low to high (75 to 300 mm mo−1equivalent) imazethapyr bioactivity declined significantly in BLS and ASL but was unaffected in QSIL. Rainfall intensity from 6 to 25 mm h−1had no effect on imazethapyr bioactivity in the three soils. A delay in rainfall application up to 14 d after herbicide application significantly reduced the bioactivity of imazethapyr in BLS but had no effect in ASL and QSIL.
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Lindh, Per, and Polina Lemenkova. "Dynamics of Strength Gain in Sandy Soil Stabilised with Mixed Binders Evaluated by Elastic P-Waves during Compressive Loading." Materials 15, no. 21 (November 4, 2022): 7798. http://dx.doi.org/10.3390/ma15217798.
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This paper addresses the problem of stabilisation of poor subgrade soil for improving its engineering properties and stiffness. The study aim is to evaluate the effects from single and mixed binders on the gain of strength in sandy soil over the period of curing. We propose an effective non-destructive approach of using P-waves for identifying soil strength upon stabilisation. The growth of strength and stiffness is strongly dependent on time of curing and type of the stabilising agents which can include both single binders and their blended mixtures. The diverse effects from mixed binders on the properties of soil were evaluated, compared and analysed. We performed the experimental trials of five different binders for stabilisation of sandy soil using cement, lime, Ground Granulated Blast Furnace Slag (GGBFS), energy fly ash and bio fly ash. The methodology included soil stabilisation by binders during a total period of 90 days, strength test for the Unconfined Compressive Strength (UCS) and seismic tests on the stabilised samples. The dynamics of soil behaviour stabilised by different binders for days 7, 14, 28 and 90 was statistically analysed and compared. The optimisation of binder blending has been performed using mixture simplex lattice design with three binders in each case as independent variables. Using P-waves naturally exploited strength characteristics of soil samples and allowed us to compare the effects from the individual and blended binders over the complete period of curing with dominating mixes. The results indicate that strength growth in stabilised soil samples is nonlinear in both time and content of binders with dominating effects from slag which contributed the most to the compressive strength development, followed by cement.
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Elzamel, Ahmed, Ayman Altahrany, and Mahmoud Elmeligy. "Utilization of Different Additives in Improving Sandy Soil against Liquefaction." Jordan Journal of Civil Engineering 17, no. 1 (January 1, 2023): 107–16. http://dx.doi.org/10.14525/jjce.v17i1.10.
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One of the main risks in low-densified sandy soils with the presence of water and an external force such as an earthquake is the generation of liquefaction. The influence of several types of reinforcement on liquefaction resistance, such as polypropylene fibers, geofibers, cement and polypropylene fibers with cement is shown in this study. Cyclic stress-controlled triaxial tests and cyclic strain-controlled triaxial tests were performed on saturated samples with and without reinforcements under undrained conditions. Cemented specimens were prepared with cement contents ranging from 0% to 3% by weight of dry sand and then cured for 3 days. The lengths of polypropylene fibers are 10 mm and 20 mm, respectively. The fibers were mixed with dry sand– cement mixes containing 0.50% and 1.00% by weight, respectively. Geofiber specimens were prepared in various arrangements. It was found that the liquefaction improvement factor (LIF) increased when fiber content and fiber length increased. The addition of geofibers increased the liquefaction resistance, as the number of layers increased. The addition of 3%C+1%F provided the best liquefaction resistance in this study compared with other additives. Finally, the reinforcement with cement and fibers is crucial for liquefaction resistanceof bitumen mastic should be considered beside the asphalt mixture performance and the bitumen rheological behavior. KEYWORDS: Liquefaction, Shear modulus, Cyclic stress, Geofiber, Polypropylene fiber.
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Balieiro, Fabiano de Carvalho, Marcos Gervasio Pereira, Bruno José Rodrigues Alves, Alexander Silva de Resende, and Avílio Antonio Franco. "Soil carbon and nitrogen in pasture soil reforested with eucalyptus and guachapele." Revista Brasileira de Ciência do Solo 32, no. 3 (June 2008): 1253–60. http://dx.doi.org/10.1590/s0100-06832008000300033.
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In spite of the normally low content of organic matter found in sandy soils, it is responsible for almost the totality of cation exchange capacity (CEC), water storage and availability of plant nutrients. It is therefore important to evaluate the impact of alternative forest exploitation on the improvement of soil C and N accumulation on these soils. This study compared pure and mixed plantations of Eucalyptus grandis and Pseudosamanea guachapele, a N2-fixing leguminous tree, in relation to their effects on soil C and N stocks. The studied Planosol area had formerly been covered by Panicum maximum pasture for at least ten years without any fertilizer addition. To estimate C and N contents, the soil was sampled (at depths of 0-2.5; 2.5-5.0; 5.0-7.5; 7.5-10.0; 10.0-20.0 and 20.0-40.0 cm), in pure and mixed five-year-old tree plantations, as well as on adjacent pasture. The natural abundance 13C technique was used to estimate the contribution of the soil organic C originated from the trees in the 0-10 cm soil layer. Soil C and N stocks under mixed plantation were 23.83 and 1.74 Mg ha-1, respectively. Under guachapele, eucalyptus and pasture areas C stocks were 14.20, 17.19 and 24.24 Mg ha-1, respectively. For these same treatments, total N contents were 0.83; 0.99 and 1.71 Mg ha-1, respectively. Up to 40 % of the soil organic C in the mixed plantation was estimated to be derived from trees, while in pure eucalyptus and guachapele plantations these same estimates were only 19 and 27 %, respectively. Our results revealed the benefits of intercropped leguminous trees in eucalyptus plantations on soil C and N stocks.
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Mohammadi, Amirhossein, Taghi Ebadi, and Mehrdad Ahmadi. "Effect of Bentonite Addition on Geotechnical Properties of Oil-Contaminated Sandy Soil." Journal of Civil Engineering and Construction 7, no. 4 (November 25, 2018): 153. http://dx.doi.org/10.32732/jcec.2018.7.4.153.
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Oil and its derivatives not only change the chemical and biological properties of the soils, but also affect their geotechnical properties. Effects of oil contamination on a sandy soil which mixed with bentonite was assessed in terms of compaction, shear strength, and consolidation behavior. The experiments were carried out by polluting dry sandy soil with 2.5, 5, 7.5, 10% w/w crude oil at different bentonite contents (0, 5, 10, 15, 20% w/w). Results of compaction tests indicated that at a fixed bentonite content, with increasing crude oil content, the maximum dry density increases, while the optimum water content decreases. Similarly, at a fixed contaminant content, increasing the bentonite content in the soil leads to increase in soil maximum dry density and the optimum moisture content. Moreover, direct shear tests revealed that at a specific bentonite content, higher contamination concentration causes lower internal friction angle. The effect of oil content on the coefficient of consolidation (Cv) and void ratio of soils with 0, 5, 10, 15, and 20 percent bentonite contents was studied. The results of consolidation tests indicated that at a fixed bentonite content Cv has an overall increasing pattern which is in its maximum amount at 5% oil content.
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Jiang, Shijie, Ming Chen, Shiyou Su, Mingkun Yang, Aihua Li, Chen Zhang, Min Lin, Wei Zhang, and Xuegang Luo. "Sphingobacterium arenae sp. nov., isolated from sandy soil." International Journal of Systematic and Evolutionary Microbiology 64, Pt_1 (January 1, 2014): 248–53. http://dx.doi.org/10.1099/ijs.0.051706-0.
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A novel, Gram-stain-negative, non-motile, non-spore-forming, short rod-shaped, aerobic bacterium designated H-12T was isolated from a mixed sandy soil sample collected from Xinjiang, China. Strain H-12T grew at 20–37 °C (optimum, 30 °C), pH 7.0–11.0 (optimum, pH 8.5) on TGY medium with 0–5 % NaCl (w/v). 16S rRNA gene sequence analysis indicated that strain H-12T shared sequence similarities with Sphingobacterium composti DSM 18850T (90.0 %). Strain H-12T showed a low level of DNA–DNA relatedness to Sphingobacterium composti DSM 18850T (45.5 %). The predominant isoprenoid quinone of strain H-12T was MK-7 and the major polar lipid was phosphatidylethanolamine. The predominant cellular fatty acids were C16:1ω7c and/or C16 : 1ω6c, iso-C15 : 0, iso-C17 : 0 3-OH, C16 : 0, C16 : 0 3-OH and iso-C15 : 0 3-OH. DNA G+C content of strain H-12T was 44.15 mol%. On the basis of phenotypic, genetic and phylogenetic data, strain H-12T is proposed to be a representative of a novel species of the genus Sphingobacterium , for which the name Sphingobacterium arenae sp. nov. is suggested and the type strain is H-12T ( = ACCC 05758T = KCTC 32294T).
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Assis, Wellyton Santos de, Elisamara Caldeira do Nascimento, Brenda D’Acunha, Oscarlina Lúcia dos Santos Weber, Eliana Freire Gaspar Dores, and Eduardo Guimarães Couto. "Effects of swine manure biochar on sorption equilibrium of cadmium and zinc in sandy soils." Agronomía Colombiana 39, no. 1 (January 1, 2021): 37–46. http://dx.doi.org/10.15446/agron.colomb.v39n1.90918.
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Swine manure is an agricultural waste that can increase soil fertility. However, this residue has a high content of heavy metals, particularly zinc (Zn) and cadmium (Cd), that are not only toxic to plants and soil organisms but they also pose a great threat to human health due to the potential accumulation of these metals through the food chain. Transforming swine manure into biochar and adding it to soils can improve the soil’s capacity to retain heavy metals. The main objective of this research was to study the capacity of sandy soils mixed with different doses of swine manure biochar (SMB) to retain Cd and Zn as well as to evaluate the sorption equilibrium of these metals. Sorption essays were performed by adding solutions of Zn (ZnCl2) or Cd (CdCl2) at different concentrations (0, 2.5, 5, 10, 50 and 100 mg L-1) to soil samples mixed with different doses of SMB (0, 0.25, 0.75, 1.5, and 3.0 % (w/w)). The data were modelled using both Langmuir and Freundlich adsorption isotherm models to describe the adsorption processes. The data were best represented by the Langmuir model (R2>0.97), indicating a mono-layer sorption to the surface. Results showed that sorption capacity of Zn and Cd increased with the dose of SMB, improving metal retention. The Langmuir constant (KL) for soil without SMB for Cd and Zn were 0.01 L mg-1 and 0.05 L mg-1, respectively. With the highest dose of SMB, KL increased to 9.86 L mg-1 and 1.26 L mg-1 for Cd and Zn, respectively. Results suggest that SMB has the potential to mitigate Zn and Cd contamination of sandy soils.
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Gronwald, M., A. Don, B. Tiemeyer, and M. Helfrich. "Effects of fresh and aged chars from pyrolysis and hydrothermal carbonization on nutrient sorption in agricultural soils." SOIL 1, no. 1 (June 18, 2015): 475–89. http://dx.doi.org/10.5194/soil-1-475-2015.
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Abstract. Leaching of nutrients from agricultural soils causes major environmental problems that may be reduced with amendments of chars derived from pyrolysis (pyrochars) or hydrothermal carbonization (hydrochars). Chars are characterized by a high adsorption capacity – i.e. they may retain nutrients such as nitrate and ammonium. However, the physicochemical properties of the chars and hence their sorption capacity likely depend on feedstock and the production process. We investigated the nutrient retention capacity of pyrochars and hydrochars from three different feedstocks (digestates, Miscanthus, woodchips) mixed into different soil substrates (sandy loam and silty loam). Moreover, we investigated the influence of char degradation on its nutrient retention capacity using a 7-month in situ field incubation of pyrochar and hydrochar mixed into soils at three different field sites. Pyrochars showed the highest ability to retain nitrate, ammonium and phosphate, with pyrochar from woodchips being particularly efficient in nitrate adsorption. Ammonium adsorption of pyrochars was controlled by the soil type of the soil–char mixture. We found some ammonium retention on sandy soils, but no pyrochar effect or even ammonium leaching from the loamy soil. The phosphate retention capacity of pyrochars strongly depended on the pyrochar feedstock with large phosphate leaching from digestate-derived pyrochar and some adsorption capacity from woodchip-derived pyrochar. Application of hydrochars to agricultural soils caused small, and often not significant, effects on nutrient retention. In contrast, some hydrochars did increase the leaching of nutrients compared to the non-amended control soil. We found a surprisingly rapid loss of the chars' adsorption capacity after field application of the chars. For all sites and for hydrochar and pyrochar, the adsorption capacity was reduced by 60–80 % to less or no nitrate and ammonium adsorption. Thus, our results cast doubt on the efficiency of char applications to temperate zone soils to minimize nutrient losses via leaching.
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Babatunde, Quadri Olakunle, and Yong-Hoon Byun. "Soil Stabilization Using Zein Biopolymer." Sustainability 15, no. 3 (January 21, 2023): 2075. http://dx.doi.org/10.3390/su15032075.
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The characterization and analysis of the cementation properties of novel biopolymer binders in soils are essential for their potential application in geotechnical engineering. This study investigates the cementation effect of a novel zein biopolymer binder on sandy soils. Soil specimens are mixed with various contents of zein biopolymer ranging from 0 to 5%. The mechanical and microscopic characteristics of the treated specimens are evaluated using unconfined compression tests and scanning electron microscopy, respectively, after curing for 3, 7, and 28 days. The results show a consistent increase in compressive strength and elastic modulus of treated soils with increasing curing periods and biopolymer contents. A small amount (1%) of zein biopolymer increases soil strength and elasticity regardless of gradation. Additionally, the bonding force between the soil–zein biopolymer increases linearly with soil uniformity. Therefore, the application of zein biopolymer can be potentially used as a binder for fine- and coarse-grained soils in geotechnical engineering considering its stabilization and sustainability properties.
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Alghamdi, Abdulaziz G., Bandar H. Aljohani, and Anwar A. Aly. "Impacts of Olive Waste-Derived Biochar on Hydro-Physical Properties of Sandy Soil." Sustainability 13, no. 10 (May 14, 2021): 5493. http://dx.doi.org/10.3390/su13105493.
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In this study, waste olive leaves and branches were pyrolyzed to produced biochar, and their impacts on physical and chemical properties of a sandy soil were evaluated. Pyrolytic temperatures of 300 °C, 400 °C, and 500 °C were used for biochar production. After evaluating the physio-chemical properties, the produced biochars were added to the top 10 cm layer of the soil at rates of 0%, 1%, 3%, and 5% in a column experiment at 25 °C. Biochar was mixed with a sandy soil into the top 10 cm of the columns. For all treatments, cumulative evaporation was reduced; however, treatments with 5% biochar prepared at the highest temperatures showed the highest impact. The available water contents were increased by 153.33% and 151.11% when olive branch-derived biochar and olive leaves-derived biochars produced at 500 °C were applied at 5% rate, respectively. No impact of available water was observed for 1% biochar contribution. Biochar application decreased both cumulative infiltration and infiltration rate. Biochar pyrolyzed at 500 °C most intensely improved hydro-physical properties of a sandy soil. However, its application as a soil supplement in arid environments should be adopted with constraints due to its high pH (9.69 and 9.29 for biochar pyrolyzed at the highest temperatures) and salinity (up to electrical conductivity = 5.07 dS m−1). However, the salinity of biochar prepared from olive branches (5%, pyrolyzed at 500 °C) was low (0.79 dS m−1); therefore, it can be used safely as a supplement in saline and acidic soils, but with restriction in alkaline soils.
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Alessandrino, Luigi, Nicolò Colombani, Vassilis George Aschonitis, and Micòl Mastrocicco. "Nitrate and Dissolved Organic Carbon Release in Sandy Soils at Different Liquid/Solid Ratios Amended with Graphene and Classical Soil Improvers." Applied Sciences 12, no. 12 (June 18, 2022): 6220. http://dx.doi.org/10.3390/app12126220.
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This study emphasizes the importance of employing parallel batch tests with different liquid/solid (L/S) ratios to assess their dissolution mechanisms. Changes in physicochemical parameters (electrical conductivity, pH, and oxidation-reduction potential), as well as the sorption/desorption of dissolved organic carbon (DOC) and nitrate (NO3−) due to graphene addition in a calcareous sandy soil (CS) and in a siliciclastic riverine sandy soil (SS) were assessed via batch experiments at different L/S ratios. Graphene’s production is growing at a great pace, so it’s important to test methods to reuse graphene wastes. The results of soil batch experiments mixed with graphene were compared with classical soil improvers (compost, biochar, and zeolites). The batches were performed using the saturation soil extraction method with deionized water as a proxy of rainwater. The contact time was 48 h. At the end of the experiment, water samples were collected to be analyzed for NO3−, DOC, DIC, Ca, and Mg. Graphene did not alter the physiochemical parameters of both soils. Moreover, its addition did not trigger any NO3− increase respect to control and to other improvers. Biochar increased EC and pH beyond recommended limits for most crops’ growth in both soils. As expected, compost addition produced the highest NO3− release.
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Sabedot, Sydney, Sérgio Augusto de Loreto Bordignon, and Ana Cristina Borda da Cunha. "Ex situ method and Salix spp. to treat polluted soil with hydrocarbon." Ciência e Natura 41 (July 16, 2019): 13. http://dx.doi.org/10.5902/2179460x29988.
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This study shows the practices for managing ex situ soil with a simulation in which a residue derived from hydrocarbons with a sandy-silty soil was mixed, and two Salix spp. varieties were planted in the mixture. The experiment took place in a greenhouse and controls on plants and soil occurred during 36 months. The experiment aimed at two objectives, the first of which was to evaluate the development and resistance of the plants in the contaminated soil, comparing them with their planting in sandy-silty soil without the residue, and the second was to evaluate the performance of plants as phytoremediators of the residue. This study deals with the first goal. The success in sprouting and in development of the plants was verified in both types of soils. The diameter and height of the stems and the dimensions of the leaves were the measured parameters. Statistical analysis of the data indicated that Salix triandra species developed better. The joint result for both the above mentioned objectives indicated that the ex situ method for treating soils contaminated with hydrocarbons and the planting of two species of willow were effective and can be reproduced in similar conditions to those described in this study.
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Shahed, A. B. M., M. A. Hossen, Al Mamun M. R., T. A. Tamanna, and M. Mizanur. "Impact of organic substance on growth attributes of mat type rice seedlings in the trays for machine transplanting." Journal of Science Technology and Environment Informatics 10, no. 1 (October 2020): 694–708. http://dx.doi.org/10.18801/jstei.100120.70.
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Rice seedling for mechanical transplanting must fulfill the prerequisites of guideline seedling block with uniform density of seedlings and between bending pulls for rolling. The present study was carried out at the Farm Power and Machinery Department, Sylhet Agricultural University, Sylhet during Boro season/2018-19 with the objective to assess the impact of organic substance on agronomic attributes of mat type rice seedling. The seedling was raised on plastic rigid tray utilizing sandy clay loam (SCL) and sandy clay (SC) soil blending with the organic fertilizer of cow-dung (CD), rice bran (RB), rice husk (RH) and tea wastage (TW) at the rate of 0.0, 5, 10, 15 and 20%, respectively. Averaged across the rate of soil mixture, 5 to 15% of CD and RB with the both types of soil gave higher seedling height, leaf length and stem length while 20% of CD and TW also showed better result for number of leaves and stem thickness. Considering all parameters, 15 to 20% rice husk and tea wastage mixed with the sandy clay loam soil and 10 to 15% with the sandy loam soil gave good result. Be that as it may, seedling quality differed among the natural composts with the two kinds of soil more or less like CD > RB > TW > RH. Water requirement in the SC soil was more compared to SCL soil. It was observed that crack was formed on the sandy clay soil in tray. For both types of soil, the density of seeds in the mat at the rate of 6-7 seeds cm-2 was found at 80% of soil mixture along with rice bran. The findings of the study could be promoted widely in farmer’s field to raise better quality of mat type seedling for better performance of the mechanical rice transplanter which ultimately leads to getting better rice yield.
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Lafleur, Peter M., J. Harry McCaughey, Paul A. Bartlett, and Ian B. Strachan. "Observations of the micrometeorology of two forests in eastern Canada. 1. Interannual variations in summer radiation and energy balance." Canadian Journal of Forest Research 28, no. 4 (April 1, 1998): 514–23. http://dx.doi.org/10.1139/x98-016.
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Measurements of radiation and energy balances were made over two forests, 12.8 km apart, in eastern Ontario during three summers, 1989-1991. The two sites were AECL, a primarily deciduous forest with fine sandy soils, and PNFI, a mixed forest over a thin sandy-loam soil. The objective of the study was to investigate spatial heterogeneity in energy fluxes in a mixed forest landscape by examining interannual variations in radiation and energy balance components between the sites. The two sites showed small differences in albedo and net radiation. Total heat storage was not different between the two sites, yet there were some differences in the relative magnitudes of the storage components. The largest between-site differences were in energy partitioning between the convective fluxes of sensible heat, QH, and latent heat, QE. The QH was usually larger at PNFI and QE was usually larger at AECL. Thus, Bowen ratios were almost always smaller at AECL. The magnitude of these differences was controlled by soil moisture stress, with moisture stress frequently observed at PNFI but not at AECL. The implications of these results for regional-scale surface-vegetation-atmosphere climate modelling are discussed.