Artículos de revistas: "Soil resistance"

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Mamatov, Farmon. "Traction Resistance of Soil Submersibility Type "Paraplau"". Journal of Advanced Research in Dynamical and Control Systems 12, SP7 (25 de julio de 2020): 2154–61. http://dx.doi.org/10.5373/jardcs/v12sp7/20202336.

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Rab, MA, KA Olsson y ST Willatt. "Resistance to water uptake by irrigated potatoes on a duplex soil". Soil Research 28, n.º 4 (1990): 487. http://dx.doi.org/10.1071/sr9900487.

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Resistances to water flow were analysed for the soil-root system of a potato crop growing on a duplex soil-where soil hydraulic properties varied with depth-under two irrigation regimes: 'wet' (irrigated weekly) and 'dry' (irrigated twice only during the growing season). The relative magnitudes of the soil and plant resistances controlling root water uptake were evaluated over depth and time using field-measured soil hydraulic properties and root length densities in successive soil layers. Resistance to water flow in the root system is likely to be the dominant resistance in the liquid phase, although soil resistance increased more rapidly than plant resistance with decreasing soil-water matric potential and root length density. Soil resistance reached similar values to plant resistance only when the soil-water matric potential was in the range -900 kPa to -1500 kPa (corresponding soil hydraulic conductivities of 10-7 and 10-8 m day-1 respectively), depending on the root length beneath unit ground area in the soil layer, La. Poor utilization of water from depth of this soil was attributed to resistance in the root system (possibly radial) associated with low La. Practical considerations for improved water management of the potato crop on clay soils are discussed.

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Pink, D. A. C. y P. Hand. "Plant resistance and strategies for breeding resistant varieties". Plant Protection Science 38, SI 1 - 6th Conf EFPP 2002 (1 de enero de 2002): S9—S14. http://dx.doi.org/10.17221/10310-pps.

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An explanation of the ‘boom-bust’ cycle of resistance breeding was provided by the gene-for-gene relationship between a pathogen and its host. Despite this understanding, most R genes continued to be deployed singly and resistance has been ephemeral. The reasons for breeding ‘single R gene’ varieties are discussed. Alternative strategies for the deployment of R genes and the use of quantitative race non-specific resistance have been advocated in order to obtain durable resistance. The feasibility of both of these approaches is discussed taking into account the impact of technologies such as plant transformation and marker-assisted selection. A change in focus from durability of the plant phenotype to that of the crop phenotype is advocated.

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Dixon, G. R. "Interactions of soil nutrient environment, pathogenesis and host resistance". Plant Protection Science 38, SI 1 - 6th Conf EFPP 2002 (1 de enero de 2002): S87—S94. http://dx.doi.org/10.17221/10326-pps.

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Host plants and soil borne pathogens that attack them exist within an ecological matrix populated by numerous microbial species that may influence the access of pathogenesis. These events are moderated by physical and chemical components of the soil. The impact of inorganic and organic nutrients on pathogenesis and the development of host resistance are discussed in this review using two host – pathogen combinations as examples. Calcium, boron, nitrogen and pH have been demonstrated to affect the processes of resting spore germination, host invasion and colonisation in the Plasmodiophora brassicae-Brassica combination that results in clubroot disease. Organic nutrients that have associated biostimulant properties have been demonstrated to influence the development of Pythium ultimum-Brassica combination that results in damping-off disease. This latter combination is affected by the presence of antagonistic microbial flora as demonstrated by increased ATP, extra-cellular enzyme and siderophore production. In both examples there are indications of the manner by which host resistance to pathogenesis may be enhanced by changes to the nutrient status surrounding host plants. These effects are discussed in relation to the development of integrated control strategies that permit disease control with minimal environmental impact.

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Ismail, Fauzilah, Mazidah Mukri y Zainab Mohamed. "Assessment of Soil Dispersibility Behaviour In-Relation to Soil Internal Erosion Resistance". Scientific Research Journal 5, n.º 1 (30 de junio de 2008): 39. http://dx.doi.org/10.24191/srj.v5i1.5652.

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A study was conducted to assess soil dispersibility behaviour in-relation to soil internal erosion resistance. Dispersive soils can be a problem for many geotechnical projects and structures. Water flowing in a crack of earth dam or infiltration of rainwater through the crack of slope surface with enough erosion energy can detach the soil particles into suspension and transport it along the movement that will lead to internal erosion process. Soil samples from sloping area within UiTM Shah Alam Campus were collected and a laboratory study was carried out to assess the soil dispersibility behaviour. A laboratory pinhole test and crumb test were conducted to identify soils which are easily dispersed hence susceptible to internal erosion. Indication of the removal of soil particles during testing is a factor in assessing the possibility of internal erosion. Fine-grained soils are known to have low resistance to erosion however laboratory result shows that soils fraction with high coarse-grained percentage has high dispersibility grade that lead to lower internal soil erosion resistance whereas the high moisture content percentage would enhance the dispersibility characteristic of the soils performance.

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Cotching, W. E. y K. C. Belbin. "Assessment of the influence of soil structure on soil strength/soil wetness relationships on Red Ferrosols in north-west Tasmania". Soil Research 45, n.º 2 (2007): 147. http://dx.doi.org/10.1071/sr06113.

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The relationship of soil wetness to soil strength in Red Ferrosols was compared between fields of well structured to degraded soil structure. Soil structure was assessed using a visual rating. Soil resistance measurements were taken over a range of soil wetness, using a recording penetrometer. Readings were taken as the soil dried by evapotranspiration after both irrigation and rainfall events. The influence of soil wetness on penetration resistance was greater on fields with degraded structure than on well-structured fields. In fields with degraded structure, the wetter the soil, the smaller were the penetration resistance values. Field soil structure score was negatively correlated with the slope of the line relating soil wetness and penetration resistance at 150–300 mm depth. The structurally degraded fields had a highly significant relationship between penetration resistance and soil wetness at 150–300 mm depth. In well-structured fields, variations in soil wetness had less effect on penetration resistance. These results indicate that visual assessment can be used with confidence to assess Ferrosol structure. The implications for soil management are that fields with degraded soil structure have greater resistance to root growth at drier moisture contents than well-structured fields. Consequently, farmers need to keep degraded soils wetter with more frequent irrigation than well-structured soils, to ensure optimum plant growth.

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Lee, Jung Hun, Kwang Seung Park, Jeong Ho Jeon y Sang Hee Lee. "Antibiotic resistance in soil". Lancet Infectious Diseases 18, n.º 12 (diciembre de 2018): 1306–7. http://dx.doi.org/10.1016/s1473-3099(18)30675-3.

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8

Izzo, Michael Z. y Marta Miletić. "Sustainable Improvement of the Crack Resistance of Cohesive Soils". Sustainability 11, n.º 20 (19 de octubre de 2019): 5806. http://dx.doi.org/10.3390/su11205806.

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Desiccation cracking of cohesive soils is the development of cracks on the soil surface as a result of a reduction in the soil moisture content. The decrease in soil surface area owing to the desiccation of cohesive soils has an undesirable impact on the mechanical, hydrological, thermal, and physico-chemical properties. Many efforts have been made to improve the desiccation crack resistance of cohesive soils, but the current solutions raise a number of environmental issues, increasing the demand for sustainable soil improvement alternatives. Therefore, the main objective of this study is to investigate novel eco-friendly soil improvement techniques, such as recycled carpet fibers and a gelatin-based bioplastic, and their effect on desiccation cracking in cohesive soils. The improvement of soil crack resistance was studied by conducting desiccation cracking tests on plain and improved soils. In addition, image processing was conducted to quantitatively describe the effect of soil improvement type on the geometrical characteristics of crack patterns. Each soil improvement technique enhanced the soil strength and reduced cracking at room temperature, at an elevated temperature, and when subjecting to cyclic wetting and drying. The addition of bioplastics proved to be the most effective solution, thus demonstrating a viable option to advance future sustainable engineering practices.

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9

Popowska, Magdalena, Marzenna Rzeczycka, Antoni Miernik, Agata Krawczyk-Balska, Fiona Walsh y Brion Duffy. "Influence of Soil Use on Prevalence of Tetracycline, Streptomycin, and Erythromycin Resistance and Associated Resistance Genes". Antimicrobial Agents and Chemotherapy 56, n.º 3 (27 de diciembre de 2011): 1434–43. http://dx.doi.org/10.1128/aac.05766-11.

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ABSTRACTThis study examined differences in antibiotic-resistant soil bacteria and the presence and quantity of resistance genes in soils with a range of management histories. We analyzed four soils from agricultural systems that were amended with manure from animals treated with erythromycin and exposed to streptomycin and/or oxytetracycline, as well as non-manure-amended compost and forest soil. Low concentrations of certain antibiotic resistance genes were detected using multiplex quantitative real-time PCR (qPCR), withtet(B),aad(A), andstr(A) each present in only one soil andtet(M) andtet(W) detected in all soils. The most frequently detected resistance genes weretet(B),tet(D),tet(O),tet(T), andtet(W) for tetracycline resistance,str(A),str(B), andaacfor streptomycin resistance, anderm(C),erm(V),erm(X),msr(A),ole(B), andvgafor erythromycin resistance. Transposon genes specific for Tn916, Tn1549, TnB1230, Tn4451, and Tn5397were detected in soil bacterial isolates. The MIC ranges of isolated bacteria for tetracycline, streptomycin, and erythromycin were 8 to >256 μg/ml, 6 to >1,024 μg/ml, and 0.094 to >256 μg/ml, respectively. Based on 16S rRNA gene similarity, isolated bacteria showed high sequence identity to genera typical of soil communities. Bacteria with the highest MICs were detected in manure-amended soils or soils from agricultural systems with a history of antibiotic use. Non-manure-amended soils yielded larger proportions of antibiotic-resistant bacteria, but these had lower MICs, carried fewer antibiotic resistance genes, and did not display multidrug resistance (MDR).

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10

Stella, P., B. Loubet, C. de Berranger, X. Charrier, E. Ceschia, G. Gerosa, A. Finco et al. "Soil ozone deposition: Dependence of soil resistance to soil texture". Atmospheric Environment 199 (febrero de 2019): 202–9. http://dx.doi.org/10.1016/j.atmosenv.2018.11.036.

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11

Chornyy, S. y O. Pismenniy. "Wind erosion resistance of steppe soils of Ukraine". Agricultural Science and Practice 1, n.º 3 (15 de diciembre de 2014): 43–49. http://dx.doi.org/10.15407/agrisp1.03.043.

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Aim. The study of direct (wind erosion resistance) and indirect (lumpiness, mechanical durability, etc) indices of current wind erosion resistance of steppe soils in Ukraine. Methods. The following methods were used: fi eld, laboratory, mathematical and statistical, analytical and comparative methods. Wind resistance of soils was studied using the elaborated method in the aerodynamic unit. Results. The studies revealed that the high- est resistance to soil blowing due to strong winds is demonstrated by light loamy chernozem, somewhat lower resistance – by southern and dark-chestnut heavy loamy chernozem, light loamy, sandy loamy and sandy turf soil. It was demonstrated that the irrigation with mineralized water enhances the indices of wind erosion resis- tance of dark-chestnut soil and southern chernozem. The granulometric analysis of soil revealed quantitative dependence between the wind erosion resistance, humus content and physical clay content. Conclusions. The studies on wind erosion resistance of dry steppe and southern steppe soils of Ukraine and the classifi cation of soil types regarding their capability of resisting strong winds allow implementing the measures of preventing wind erosion.

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Zadorozhnaya, Galina A., Kateryna V. Andrusevych y Olexander V. Zhukov. "Soil heterogeneity after recultivation: ecological aspect". Folia Oecologica 45, n.º 1 (1 de mayo de 2018): 46–52. http://dx.doi.org/10.2478/foecol-2018-0005.

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Abstract The study subject was the soil heterogeneity at a recultivation site Nikopol manganese-ore basin (Pokrov, Ukraine). The soils at the locality are sod lithogenic soils developed on gray-green clays. The study ran by applying soil penetration resistance indices. The penetration resistance was measured across a regular grid of 7 × 15 points (21 × 45 m). The distance between the measurement points was 3 m. The parameters were recorded at every 5 cm to a depth of 50 cm. The environmental parameters were determined by phytoindication. Geostatistical analysis showed the average level of spatial dependence of soil penetration resistance. According to the features of the profile variation in penetration resistance with the depth, the measurement points have been divided into three clusters. The clusters formed morphologically homogeneous soil areas. These areas significantly differed in their soil acidity and in nitrogen content in soil.

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13

Seybold, C. A., D. S. Harms y R. B. Grossman. "Describing Soils: Calibration Tool for Teaching Soil Rupture Resistance". Journal of Natural Resources and Life Sciences Education 38, n.º 1 (2009): 11–15. http://dx.doi.org/10.2134/jnrlse2009.38111x.

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14

Meskele, Tadesse y Armin W. Stuedlein. "Static Soil Resistance to Pipe Ramming in Granular Soils". Journal of Geotechnical and Geoenvironmental Engineering 141, n.º 3 (marzo de 2015): 04014108. http://dx.doi.org/10.1061/(asce)gt.1943-5606.0001237.

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15

Krasinski, Adam. "The Analysis of Soil Resistance During Screw Displacement Pile Installation". Studia Geotechnica et Mechanica 36, n.º 3 (28 de febrero de 2015): 49–56. http://dx.doi.org/10.2478/sgem-2014-0026.

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Abstract The application of screw displacement piles (SDP) is still increasing due to their high efficiency and many advantages. However, one technological problem is a serious disadvantage of those piles. It relates to the generation of very high soil resistance during screw auger penetration, especially when piles are installed in non-cohesive soils. In many situations this problem causes difficulties in creating piles of designed length and diameter. It is necessary to find a proper method for prediction of soil resistance during screw pile installation. The analysis of screw resistances based on model and field tests is presented in the paper. The investigations were carried out as part of research project, financed by the Polish Ministry of Science and Higher Education. As a result of tests and analyses the empirical method for prediction of rotation resistance (torque) during screw auger penetration in non-cohesive subsoil based on CPT is proposed.

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Badalíková, Barbora, Bartlová J. y Vymyslický T. "Changes in Soil Structure and Water Resistance of Soil Aggregates after the Application of Wine Marc Compost". Modern Environmental Science and Engineering 1, n.º 4 (20 de diciembre de 2015): 199–203. http://dx.doi.org/10.15341/mese(2333-2581)/04.01.2015/007.

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17

CARTER, M. R. "PENETRATION RESISTANCE TO CHARACTERIZE THE DEPTH AND PERSISTENCE OF SOIL LOOSENING IN TILLAGE STUDIES". Canadian Journal of Soil Science 68, n.º 4 (1 de noviembre de 1988): 657–68. http://dx.doi.org/10.4141/cjss88-063.

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Soil penetration resistance was used to characterize tillage-induced changes in soil strength, as a functon of soil depth and time, under three reduced tillage systems and a deep tillage study in loam to fine sandy loam, Podzolic and Luvisolic soils. The penetration resistance measurements quantified the depth, degree, and persistence of soil loosening, and potential soil rooting depth in regard to tillage system. Mouldboard ploughing provided a greater degree of soil loosening than chisel ploughing. The potential soil rooting depth of 33 – 36 cm under mouldboard ploughing was decreased to 26 cm under both direct drilling and shallow tillage. Use of a slant-legged subsoiler (i.e., “paraplow”) prior to direct drilling prevented the reduction in soil rooting depth. The depth of soil loosening gradually declined by 30 and 60%, over a 5-mo period, under mouldboard ploughing and the "paraplow" direct drilling system, respectively. Residual tillage effects and soil compaction after deep loosening were quantified by the penetration resistance measurements. The use of penetration resistance to rapidly screen soil depth to critical levels of soil strength demonstrated that under sequential direct drilled systems soil loosening should occur on a regular basis to maintain optimum soil structure on fine sandy loam soils. Key words: Soil strength, penetration resistance, reduced tillage, Podzolic soil, Luvisolic soil

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18

Levy;, S. B. "Mechanisms for Resistance in Soil". Science 312, n.º 5773 (28 de abril de 2006): 529a. http://dx.doi.org/10.1126/science.312.5773.529a.

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Alfiani, Nofita, Koddam Rukadi L y Frida Agung Rakhmadi. "Resistance Characteristics of Soil Fertility". Proceeding International Conference on Science and Engineering 2 (1 de marzo de 2019): 131–32. http://dx.doi.org/10.14421/icse.v2.70.

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Fertile soil is an important indication to support plant growth. The more fertile a soil then plant growth, the better. In this study, the method used is to measure the resistance of different types of fertilizer are manure, compost. Because different forms of land then the resistance will also vary according to the shape of the land. The results obtained are cage fertilizer that has the smallest resistance is 39.7 Ω and 33.6 Ω whereas compost and 35.4 Ω 41.9 Ω. The benefits of this method were to determine the resistance or resistance from the ground. So the lower the ground obstacles, the more fertile the land. Conversely, the higher the resistance of the soil, the more the soil is not fertile.

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Robbins, Donald H., Clarence E. Johnson, Robert L. Schafer y Thomas R. Way. "Modeling Soil-Metal Sliding Resistance". Transactions of the ASABE 64, n.º 2 (2021): 435–46. http://dx.doi.org/10.13031/trans.13978.

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HighlightsA model was developed to express soil-metal sliding resistance in terms of normal stress and sliding path length.Soil-metal sliding resistance data, different from those used to develop the model, were acceptably simulated.The model is expected to be useful in the design and development of soil-engaging equipment.Abstract. Most previous soil-material sliding resistance studies have focused on the measurement and formulation of only qualitative relationships between sliding resistance and the material type, applied normal stress, sliding path length, and/or soil-properties. Few studies have attempted to formulate quantitative mathematical relationships between soil-material sliding resistance and these factors, or to mathematically express the relative contributions of the frictional and adhesive components to the total sliding resistance. In this study, a mathematical model was developed to express the components of soil-metal sliding resistance for a clay soil as functions of applied normal stress and sliding path length. The model is restricted to soil containing enough moisture to exhibit cohesive strength, but not so much moisture to exhibit gross plastic behavior. Soil-metal sliding resistance data, different from those used to develop the model, were acceptably simulated, as the mean square error between the simulated sliding resistance and the measured sliding resistance ranged from 0.653 to 2.44. Keywords: Adhesion, Friction, Normal stress, Sliding path length, Sliding resistance.

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21

Javadzadeh, P. "Investigating the Effect of Nanomaterials on Resistance Parameters of Clay Soil". Journal of Applied Engineering Sciences 9, n.º 2 (1 de diciembre de 2019): 139–44. http://dx.doi.org/10.2478/jaes-2019-0019.

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Abstract In recent years, nano technology has been significantly implemented in geotechnical engineering, especially for soil remediation. Using this technology has improved soil resistance parameters and led to the stabilization of many problematic soils. Clay soils, due to their nature, have a large dispersion on the surface of the earth. The widespread dispersion of these types of soils in the site of structures, describes the necessity of studying and investigating new methods of improving and amending the resistive properties of these soils. This research is a review of the use of nanotechnology for the improvement of soil resistive properties by geotechnical researchers.

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Cohen, Y. "Systemic induced resistance". Plant Protection Science 38, SI 1 - 6th Conf EFPP 2002 (1 de enero de 2002): S122—S125. http://dx.doi.org/10.17221/10334-pps.

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Biotic and abiotic agents may induce resistance in plants against pathogens. Abiotic agents may be synthetic or natural. The natural, non-protein amino acid BABA (DL-β-aminobutyric acid) induces systemic resistance in crop plants against pathogens. Dry, killed mycelia of Penicillium chrysogenum (DM) induces local resistance in plants against soil-borne pathogens. The activity of BABA and DM are described here in detail. Both products were shown to effectively control plant disease in nature.

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23

Zadorozhnaya, Galina. "Spatiotemporal Dynamics of Soil Penetration Resistance of Recultivated Soil". Ekológia (Bratislava) 37, n.º 1 (1 de marzo de 2018): 82–89. http://dx.doi.org/10.2478/eko-2018-0008.

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AbstractThis article examines changes in the spatial distribution of soil penetration resistance in ordinary chernozem (Calcic Chernozem) and in the recultivated soil in 2012 and 2014. The measurements were carried out in the field using an Eijkelkamp penetrometer on a regular grid. The depth of measurement was 50 cm, the interval was 5 cm. The indices of variation of soil penetration resistance in space and time have been determined. The degree of spatial dependence of soil penetration resistance has been determined layer by layer. The nature of temporal dynamics of soil penetration resistance of chernozem and technical soil has been described. A significant positive relationship of the structure of chernozem in the two years of the research has been shown. Significant correlations between the data of different years in the technical soil were found to be mostly negative.

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Silva, Wininton M. da, Aloísio Bianchini y Cesar A. da Cunha. "Modeling and correction of soil penetration resistance for variations in soil moisture and soil bulk density". Engenharia Agrícola 36, n.º 3 (junio de 2016): 449–59. http://dx.doi.org/10.1590/1809-4430-eng.agric.v36n3p449-459/2016.

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ABSTRACT This study aimed to describe the behavior of models for adjusting data of soil penetration resistance for variations in soil moisture and soil bulk density. The study was carried out in Lucas do Rio Verde, MT, Brazil in a typic dystrophic red-yellow Latosol (Oxisol) containing 0.366 kg kg−1 of clay. Soil penetration resistance measurements were conducted in the soil moistures of 0.33 kg kg−1, 0.28 kg kg−1, 0.25 kg kg−1 and 0.22 kg kg−1. Soil penetration resistance behavior due to variations in soil moisture and soil bulk density was assessed by estimating the soil resistance values by non-linear models. There was an increase of the soil penetration resistance values as soil was losing moisture. For the same edaphic condition studied, small differences in the data of soil bulk density affect differently the response of soil resistance as a function of moisture. Both soil bulk density and soil moisture are essential attributes to explain the variations in soil penetration resistance in the field. The good representation of the critical soil bulk density curve as a limiting compression indicator requires the proper choice of the restrictive soil resistance value for each crop.

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Sato, Kyo. "Effect of a pesticide pentachlorophenol on soil microflora. III. Growth rates as an index of pesticide resistance of bacterial groups isolated from soil". Canadian Journal of Microbiology 33, n.º 9 (1 de septiembre de 1987): 819–22. http://dx.doi.org/10.1139/m87-141.

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Pentachlorophenol resistance was investigated in bacteria isolated from glycine- or water-percolated soils where the bacterial flora was modified by the addition of pentachloropenol. The strains isolated from the water-percolated soil amended with PCP had the highest resistance, and the addition of glycine to the percolated soil weakened the resistance. The strains from the glycine-percolated soil without pentachlorophenol had a medium degree of resistance, and the resistance of the strains from the water-percolated soil without PCP was the lowest. The bacterial groups were sorted taxonomically; differences in pentachloropenol resistance were correlated with taxonomic groupings. Relative growth rate in the presence of pentachlorophenol was proposed as a useful means to distinguish among the bacterial species.

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Bogunović, Igor, Péter Gergő Kovács, Igor Dekemati, Ivica Kisić, István Balla y Márta Birkás. "Long-term effect of soil conservation tillage on soil water content, penetration resistance, crumb ratio and crusted area". Plant, Soil and Environment 65, No. 9 (9 de octubre de 2019): 442–48. http://dx.doi.org/10.17221/249/2019-pse.

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Conservation tillage harmonizes soil protection with demands of the crop, soil and climate. The continuous conservation tillage improves soil properties and modifies impact of weather extremes. The aim of the paper was to investigate the changes in four soil physical states affected by soil conservation tillage and to evaluate soil water content in a critical period. The study was carried out on Chernozems applying six tillage treatments, that are loosening, ploughing, tine tillage (a deeper, and a shallower), disk tillage and direct drilling. The investigation suggested that soil conservation was the major solution resulting in the balanced water content (SWC) and penetration resistance values in both treatments under peculiar weather conditions. However, the crumb ratio and the crusted area resulted in significant differences between the treatments, presumably due to the level of surface preservation. Soil water content differed significantly between months, with higher contents in spring and lower values in the end of summer. The higher SWC expected at the beginning of the growing season was reliably fulfilled, but the SWC level for workabilty differed from the optimum.

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Varga, František, Miroslav Mojžiš y Rudolf Abrahám. "Soil Resistance and its Impact on Tillage Depth". Acta Technologica Agriculturae 16, n.º 1 (1 de marzo de 2013): 26–30. http://dx.doi.org/10.2478/ata-2013-0007.

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Abstract Currently manufactured tractors are equipped with a three-point hitch, which is used to connect semi-mounted implements to the tractor. The tractor three-point hitch is operated hydraulically, using various types of control. The most commonly used control is a force, positional and a mixed one. Each of these types of control has its specific characteristics and some advantages and disadvantages. Finally, each type of control is suitable for certain soil and terrain conditions. Particular attention was paid to a force control, which is improving the use of the tractor with a mounted implement, but on the other hand, adversely affects the uniformity of working depth of implements on soils with variable resistance. Based on theoretical analysis and experimental measurements, there has been determined the effect of soil resistance on the tillage depth, depending on initial conditions for implement deepening. Initial conditions for implement deepening are given by the tillage depth, soil resistance, and the cutting width of a plough. It was found that soil resistance strongly affects the tillage depth, and with increasing soil resistance the tillage depth decreases non-linearly. A gradual increasing of soil resistance is associated with a less-marked decreasing of the tillage depth. These facts will be further used in research, development and experimental verification of new control systems of the three-point hitch of tractors.

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Bergado, D. T., K. C. Macatol, N. U. Amin, J. C. Chai, M. C. Alfaro y L. R. Anderson. "Interaction of lateritic soil and steel grid reinforcement". Canadian Geotechnical Journal 30, n.º 2 (1 de abril de 1993): 376–84. http://dx.doi.org/10.1139/t93-032.

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Laboratory and field pullout tests were carried out to study the interaction of welded steel grid reinforcements embedded in lateritic residual soil backfill. The laboratory pullout tests were conducted on various reinforcement sizes, mesh geometries, normal pressures, and compaction conditions of the backfill material. Field pullout tests were conducted at representative overburden, field-moisture, and density conditions. From the test results, it was found that the longitudinal members yielded frictional resistance from 8 to 15% of the total grid pullout resistance. Thus, the major contribution to the pullout resistance of grid reinforcements consists of the passive resistance mobilized in front of the transverse members. The maximum pullout resistance is shown by a bilinear curve which displayed similarity with the failure envelope from direct shear tests of the backfill material. This bilinear envelope reinforced the previous observation regarding the effect of particle breakage phenomenon inherent to lateritic residual soils subjected to high normal pressures. Comparisons between laboratory and field pullout resistances and between the predicted passive resistance and the laboratory test data are also presented. Key words : reinforcement, laboratory test, earthfill, compaction, friction resistance.

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Pamuk, Ahmet, Patricia Gallagher y Korhan Adalier. "Soil Grouting as Seismic Liquefaction Countermeasure". Advanced Materials Research 1025-1026 (septiembre de 2014): 1035–40. http://dx.doi.org/10.4028/www.scientific.net/amr.1025-1026.1035.

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This paper presents a series of centrifuge tests studying the performance of colloidal silica grouted soil layers during permanent lateral ground deformations due to earthquake induced lateral spreading. Two centrifuge tests were conducted to study liquefaction resistance of liquefiable soil deposits stabilized with colloidal silica, and then the results were compared with the tests conducted on similar soil deposits without any soil remediation. The testing results on remediated soils showed excellent resistance against the liquefaction and associated lateral and vertical ground deformations.

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Verley, R. L. P. y T. Sotberg. "A Soil Resistance Model for Pipelines Placed on Sandy Soils". Journal of Offshore Mechanics and Arctic Engineering 116, n.º 3 (1 de agosto de 1994): 145–53. http://dx.doi.org/10.1115/1.2920143.

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This paper presents a pipe-soil interaction model for sand soils capable of predicting the development of pipe penetration into the soil and the associated soil resistance that may be mobilized against horizontal pipe motions. The model is based on dimensional analysis and development of appropriate empirical equations which are fitted to large-scale laboratory data from several sources. The development of penetration is described by considering the work done by the pipe on the soil. For a given penetration, the force-displacement curve is described. The model has been used to predict time histories of penetration and horizontal pipe displacement from large-scale laboratory tests where pipe sections were subjected to forces representative of those from irregular waves and currents. A good reproduction of the time development of both penetration and displacement is given over the whole range of relevant hydrodynamic and soil parameters.

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31

Liebig, M. A., J. R. Hendrickson, J. D. Berdahl y J. F. Karn. "Soil resistance under grazed intermediate wheatgrass". Canadian Journal of Soil Science 88, n.º 5 (1 de noviembre de 2008): 833–36. http://dx.doi.org/10.4141/cjss08016.

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Intermediate wheatgrass [Thinopyrum intermedium (Host) Barkw. & D.R. Dewey subsp. intermedium] is a productive, high-quality perennial forage that lacks persistence under grazing. A study was conducted to evaluate the effects of three grazing times on soil bulk density, soil pH, and soil organic C under intermediate wheatgrass. Treatment effects on the three soil attributes were negligible, implying grazing time did not negatively impact intermediate wheatgrass beyond a threshold whereby critical soil functions were impaired. Findings from this study are important in the context of sustainable forage and cropping system management, where maintaining or improving critical soil functions are essential for enhancing agroecosystem sustainability. Key words: Seeded perennial forages, Northern Great Plains, soil organic C

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32

Roque, Pedro, Mariana Motta y Tácio de Campos. "Suction effects on the tensile strength and unconfined compression of unsaturated soils". MATEC Web of Conferences 337 (2021): 01016. http://dx.doi.org/10.1051/matecconf/202133701016.

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The soil-water characteristic curve is an important relation of unsaturated soils, that expresses the variation of the amount of water retained in the soil as a function of its suction. In these soils, drying or wetting can have a great influence on their resistance parameters. This work presents and discusses the effects of increased suction on the tensile strength and unconfined compression of unsaturated soils. Suction was evaluated using the filter paper and the dew point technique, while the resistance parameters were obtained through the “Brazilian Test” and uniaxial compression. Three different soils from Rio de Janeiro were studied: two young residual soils, in which the influence of the soil structure was also verified through tests on undisturbed and reconstituted samples, and a colluvial soil. The results allowed to conclude that the increase of suction, in a first moment, generates an increase in the resistance parameters of these soils. With the continuation of the drying process, the mechanical behaviour of the soils varied, being able to maintain the resistance or showing a drop related to high suction values.

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33

Stošić, Miro, Vladimir Zebec, Maciej Kluz, Boris Ravnjak, Tomislav Vinković y Bojana Brozović. "Soil resistance and bulk density under different tillage system". Poljoprivreda 26, n.º 1 (23 de junio de 2020): 17–24. http://dx.doi.org/10.18047/poljo.26.1.3.

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A stationary field experiment of a reduced soil tillage was implemented at a Hypogley (Hypogleyic soils A–Gso–Gr soil horizon sequence) soil type of Eastern Croatia during three seasons and set up as a split-plot randomized block design in four repetitions. The tillage systems (TS) were as follows: 1) conventional tillage, i.e., plowing at 30 cm (CT), 2) disking up 10-12 cm (DT), 3) soil loosening up to 35 cm (LT), 4) no-tillage (NT). The experiment was designed to compare the penetration resistance (PR), soil moisture (SM), and bulk density (BD) at different TSs and soil depths. A cone penetrometer was used to measure the PR with 10 prods per TS, accompanied with a measurement of SM with a soil auger on every 10 cm, with four samples up to a 40-cm depth. The BD was determined by metal cylinders on every 10 cm up to a 30-cm depth, being weighed and dried thereafter to obtain an absolutely dry sample, and then calculated using absolutely a dry soil sample mass (m_s) and the soil volume (V). The PR and SM were significantly influenced by the TS and soil depth. The CT had the significantly lowest PR at all depths, while the DT has manifested a significantly higher PR at a soil depth amounting to 10 to 20 cm. The PR on NT were significantly diverse from the CT at all soil depths. The BD varied significantly concerning the TS and the soil depth. Subsequent to the three years, the CT had a significantly smaller BD at a depth amounting from 0 to 10 cm, and a significantly higher BD at 20- to 30-cm depth, compared to reduce the TS.

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34

Yarba, Necmi y Ekrem Kalkan. "Freeze-Thaw Resistance of Fine-Grained Soils Stabilized with Waste Material Mixtures". International journal of Science and Engineering Applications 9, n.º 12 (3 de diciembre de 2020): 158–63. http://dx.doi.org/10.7753/ijcatr0912.1005.

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This paper evaluates the use of waste material mixtures including marble dust and scrap tire rubber the stabilization of fine-grained soils in order to remove the effects of freeze-thaw cycles. In this study, a fine-grained soil material was stabilized by using waste material mixtures. Natural and stabilized fine-grained soil samples were subjected to freeze-thaw cycles under different curing periods. After the freeze-thaw cycles, compressive strength tests were performed to investigate effects of waste material mixtures on the freeze-thaw resistance of fine-grained soil samples. The experimental results showed that the samples of fine-grained soil stabilized with waste material mixtures have high freeze-thaw durability as compared to unstabilized fine-grained soil samples. Consequently, we conclude that waste material mixtures including marble dust and scrap tire rubber, can be successfully used as an additive material to enhance the freeze-thaw durability of fine-grained soils for soil stabilization in the geotechnical applications.

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35

Yarbaşı, Necmi y Ekrem Kalkan. "Freeze-Thaw Resistance of Fine-Grained Soils Stabilized with Waste Material Mixtures". International journal of Science and Engineering Applications 10, n.º 1 (1 de enero de 2021): 001–6. http://dx.doi.org/10.7753/ijsea1001.1001.

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This paper evaluates the use of waste material mixtures including marble dust and scrap tire rubber the stabilization of fine-grained soils in order to remove the effects of freeze-thaw cycles. In this study, a fine-grained soil material was stabilized by using waste material mixtures. Natural and stabilized fine-grained soil samples were subjected to freeze-thaw cycles under different curing periods. After the freeze-thaw cycles, compressive strength tests were performed to investigate effects of waste material mixtures on the freeze-thaw resistance of fine-grained soil samples. The experimental results showed that the samples of fine-grained soil stabilized with waste material mixtures have high freeze-thaw durability as compared to unstabilized fine-grained soil samples. Consequently, we conclude that waste material mixtures including marble dust and scrap tire rubber, can be successfully used as an additive material to enhance the freeze-thaw durability of fine-grained soils for soil stabilization in the geotechnical applications.

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36

Lehmann, P., O. Merlin, P. Gentine y D. Or. "Soil Texture Effects on Surface Resistance to Bare‐Soil Evaporation". Geophysical Research Letters 45, n.º 19 (2 de octubre de 2018): 10,398–10,405. http://dx.doi.org/10.1029/2018gl078803.

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37

SALAM, Md Abdus, Quazi Mehbubar RAHMAN, Swee Peng ANG y Fushuan WEN. "Soil resistivity and ground resistance for dry and wet soil". Journal of Modern Power Systems and Clean Energy 5, n.º 2 (1 de octubre de 2015): 290–97. http://dx.doi.org/10.1007/s40565-015-0153-8.

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38

LaPara, Timothy M. "Antibiotic Resistance from Digesters to Soil". Proceedings of the Water Environment Federation 2016, n.º 3 (1 de enero de 2016): 611–15. http://dx.doi.org/10.2175/193864716821125349.

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39

Zhakulin, A. S., Aisulu Zhakulina, V. N. Popov, Yerken Akhmetov y Altay Zhakulin. "Design soil resistance for deep foundation". Japanese Geotechnical Society Special Publication 2, n.º 7 (2016): 350–53. http://dx.doi.org/10.3208/jgssp.kaz-09.

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40

Tyrrell, Ciara, Catherine M. Burgess, Fiona P. Brennan y Fiona Walsh. "Antibiotic resistance in grass and soil". Biochemical Society Transactions 47, n.º 1 (19 de febrero de 2019): 477–86. http://dx.doi.org/10.1042/bst20180552.

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Abstract Antibiotic resistance is currently one of the greatest threats to human health. The global overuse of antibiotics in human medicine and in agriculture has resulted in the proliferation and dissemination of a multitude of antibiotic resistance genes (ARGs). Despite a large proportion of antibiotics being used in agriculture, little is understood about how this may contribute to the overall antibiotic resistance crisis. The use of manure in agriculture is a traditional and widespread practice and is essential for returning nutrients to the soil; however, the impact of continuous manure application on the environmental microbiome and resistome is unknown. The use of antibiotics in animal husbandry in therapeutic and sub-therapeutic doses creates a selective pressure for ARGs in the gut microbiome of the animal, which is then excreted in the faeces. Therefore, the application of manure to agricultural land is a potential route for the transmission of antibiotic-resistant bacteria from livestock to crops, animals and humans. It is of vital importance to understand the mechanisms behind ARG enrichment and its maintenance both on the plant and within the soil microbiome to mitigate the spread of this resistance to animals and humans. Understanding this link between human health, animal health, plant health and the environment is crucial to inform implementation of new regulations and practice regarding antibiotic use in agriculture and manure application, aimed at ensuring the antibiotic resistance crisis is not aggravated.

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41

Mahdavi, S. M. y H. Fujimaki. "Soil Salinity Resistance Effect on Evaporation". Eurasian Soil Science 52, n.º 5 (mayo de 2019): 526–34. http://dx.doi.org/10.1134/s1064229319050089.

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42

Grigoryan, L. R., N. M. Bogatov y A. L. Grigoryan. "DEVELOPMENT OF SPECIFIC MEASURER SOIL RESISTANCE". Vestnik of Ryazan State Radio Engineering University 66-1 (2018): 147–52. http://dx.doi.org/10.21667/1995-4565-2018-66-4-1-147-152.

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43

Jesenská, Zdenka, Elena Piecková y D. Bernát. "Heat resistance of fungi from soil". International Journal of Food Microbiology 19, n.º 3 (agosto de 1993): 187–92. http://dx.doi.org/10.1016/0168-1605(93)90076-s.

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44

Sun, Xiaohao, Linchang Miao, Runfa Chen, Hengxing Wang, Linyu Wu y Jinxin Xia. "Liquefaction Resistance of Biocemented Loess Soil". Journal of Geotechnical and Geoenvironmental Engineering 147, n.º 11 (noviembre de 2021): 04021117. http://dx.doi.org/10.1061/(asce)gt.1943-5606.0002638.

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45

Błażejczak, Dariusz, Jan Jurga y Jarosław Pytka. "Data Grouping Method for the Purpose of Forecasting the Mechanical Strength of Plastic Soils". Agronomy 10, n.º 4 (17 de abril de 2020): 578. http://dx.doi.org/10.3390/agronomy10040578.

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The aim of this work was to develop a method of data grouping (DGM) that enables the selection of regression equations for forecasting soil penetration resistance based on an easily available and small set of input data: soil moisture content, soil bulk density and the grain size distribution of the soil. Models for forecasting the penetration resistance were created by selecting regression equations for specific intervals of granulometric variability of soil fractions. A field measurements campaign was conducted and soil samples were taken from the subsoil on 43 profiles, at depths of 25–30, 35–40, 45–50 and 55–60 cm. It was found that the dry bulk density is much less useful for predicting the penetration resistance of plastic soils than soil moisture. The study also showed that it is possible to forecast the soil penetration resistance on the basis of the gravimetric moisture content and the soil specific surface.

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46

Ravshanov, Hamrokul, Farmon Mamatov, Odil Primov, Shakhnoza Khazratkulova y Dilshod Baratov. "Study on technological properties of winter wheat soils". E3S Web of Conferences 304 (2021): 03010. http://dx.doi.org/10.1051/e3sconf/202130403010.

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The aim of the study is to study and analyze the physical, mechanical and technological properties of soils from under winter grain crops in the hot climate of Uzbekistan. The results of determining the moisture content, density, hardness and resistance to various deformations of soils after harvesting winter wheat are presented. The basic principles and methods of classical mechanics, mathematical analysis and statistics were used in this study. Studies have found that, in the layer 0-30, the soil moisture for ten days after harvesting winter cereals decreases by 12.1-16.3%, and the soil hardness increases by 10.7-16.4% and are 3.22-5.14 MPa. At the same time, at an average humidity of 12-14%, the resistance of the soil to breakage and torsion, respectively, is 1.3-1.8 and 1.0-1.1 times higher than the resistance of the soil to shear. The resistance of the soil to shear is 87.9 kPa, and to breakage and torsion-69.7 and 78.6 kPa, respectively.

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47

Bulmer, C. E. y M. Krzic. "Soil properties and lodgepole pine growth on rehabilitated landings in northeastern British Columbia". Canadian Journal of Soil Science 83, n.º 4 (1 de agosto de 2003): 465–74. http://dx.doi.org/10.4141/s03-013.

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We determined post-establishment tree growth and soil properties on rehabilitated log landings and forest plantation sites with medium texture in northeastern British Columbia. Six years after rehabilitation treatments were applied, 60% of rehabilitated landing plots had more than 1000 stems ha-1, while 17% had fewer than 600 stems ha-1. The average height of undamaged lodgepole pine trees on rehabilitated landings was consistently lower than for trees of the same age on plantations. Surface (0–7 cm) and subsurface (10–17 cm) soil bulk densities were higher for rehabilitated landings than for adjacent plantations. Rehabilitated landing and plantation soils had similar values of total and aeration porosity. Plantation soils had higher available water storage capacity (AWSC) than rehabilitated soils. Soil mechanical resistance after landing rehabilitation was often higher than for plantation soils at the same depth. Soils on both rehabilitated landings and plantations showed an increase in mechanical resistance from June to September 2001. With the exception of June 2001, soil mechanical resistance after landing rehabilitation was often higher than 2500 kPa. For surface mineral soils, there were no differences in total C, N, or cation exchange capacity (CEC) between rehabilitated landings and plantations. Rehabilitated landing soils had significantly higher total C and N at 10–17 cm depth than plantation soils, which coincided with higher clay content for the landing subsoils. Key words: Forest soil rehabilitation, soil degradation, soil productivity, soil conservation

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48

Zhou, Cheng, Zhongyou Ma, Xiaoming Lu, Lin Zhu y Jianfei Wang. "Phenolic Acid-Degrading Consortia Increase Fusarium Wilt Disease Resistance of Chrysanthemum". Agronomy 10, n.º 3 (12 de marzo de 2020): 385. http://dx.doi.org/10.3390/agronomy10030385.

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Soil microbial community changes imposed by the cumulative effects of root-secreted phenolic acids (PAs) promote soil-borne pathogen establishment and invasion under monoculture systems, but the disease-suppressive soil often exhibits less soil-borne pathogens compared with the conducive soil. So far, it remains poorly understood whether soil disease suppressiveness is associated with the alleviated negative effects of PAs, involving microbial degradation. Here, the long-term monoculture particularly shaped the rhizosphere microbial community, for example by the enrichment of beneficial Pseudomonas species in the suppressive soil and thus enhanced disease-suppressive capacity, however this was not observed for the conducive soil. In vitro PA-degradation assays revealed that the antagonistic Pseudomonas species, together with the Xanthomonas and Rhizobium species, significantly increased the efficiency of PA degradation compared to single species, at least partially explaining how the suppressive soil accumulated lower PA levels than the conducive soil. Pot experiments further showed that this consortium harboring the antagonistic Pseudomonas species can not only lower PA accumulation in the 15-year conducive soils, but also confer stronger Fusarium wilt disease suppression compared with a single inoculum with the antagonistic bacteria. Our findings demonstrated that understanding microbial community functions, beyond the single direct antagonism, facilitated the construction of active consortia for preventing soil-borne pathogens under intensive monoculture.

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49

Masle, J., GD Farquhar y RM Gifford. "Growth and Carbon Economy of Wheat Seedlings as Affected by Soil Resistance to Penetration and Ambient Partial Pressure of CO2". Functional Plant Biology 17, n.º 4 (1990): 465. http://dx.doi.org/10.1071/pp9900465.

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Wheat seedlings were grown on soils with different resistances to root penetration and at various ambient partial pressures of CO2, pa. The partial pressure pa was varied either (a) as soon as seedlings emerged and until the end of the experiment (i.e. until c. 2 weeks after sowing, until the three leaf stage) or (b) only after the effects of high soil resistance were well established, and then for two days. In the first week after emergence, a higher soil resistance induced slower growth of both roots and shoot. This effect was independent of pa. We conclude that at this stage, with much of the plant's carbon being supplied from hydrolysis of seed reserves, growth at high soil resistance was not C-source limited. There was, however, a positive relationship between shoot growth rate and the carbohydrate concentration in that tissue, the degree of which varied with soil resistance. A given carbohydrate concentration was associated with a lower growth rate at high, compared with low, soil resistance. We deduced that this reduced sensitivity of growth to internal availability of substrate carbohydrate may be one manifestation of a sink limitation. Subsequent to the first week following emergence, roots grew faster on soil with higher resistance, while the shoot continued to grow more slowly. As seed reserves were becoming exhausted, growth became sensitive to pa, i.e. somewhat source-limited. This response to partial pressure of CO2 was mainly seen in the roots. The correlation between growth rate and carbohydrate levels was maintained. We conclude that increased soil resistance induces a factor which retards shoot growth, partly by decreasing its sensitivity to carbohydrate levels, making more carbon available for root growth. It is unclear whether or not this factor also directly affects the physiology of the roots. A higher soil resistance resulted in greater respiratory losses as a proportion, Φ, of carbon fixation. Reduced pa also induced greater Φ. Theory is developed relating Φ to carbon assimilation, allocation and maintenance. It leads to the prediction that respiratory losses, as a proportion, Φ, should be increased under most environmental conditions which reduce relative growth rate.

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50

Tang, J. Y. y W. J. Riley. "A new top boundary condition for modeling surface diffusive exchange of a generic volatile tracer: theoretical analysis and application to soil evaporation". Hydrology and Earth System Sciences 17, n.º 2 (28 de febrero de 2013): 873–93. http://dx.doi.org/10.5194/hess-17-873-2013.

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Abstract. We describe a new top boundary condition (TBC) for representing the air–soil diffusive exchange of a generic volatile tracer. This new TBC (1) accounts for the multi-phase flow of a generic tracer; (2) accounts for effects of soil temperature, pH, solubility, sorption, and desorption processes; (3) enables a smooth transition between wet and dry soil conditions; (4) is compatible with the conductance formulation for modeling air–water volatile tracer exchange; and (5) is applicable to site, regional, and global land models. Based on the new TBC, we developed new formulations for bare-soil resistance and corresponding soil evaporation efficiency. The new soil resistance is predicted as the reciprocal of the harmonic sum of two resistances: (1) gaseous and aqueous molecular diffusion and (2) liquid mass flow resulting from the hydraulic pressure gradient between the soil surface and center of the topsoil control volume. We compared the predicted soil evaporation efficiency with those from several field and laboratory soil evaporation measurements and found good agreement with the typically observed two-stage soil evaporation curves. Comparison with the soil evaporation efficiency equation of Lee and Pielke (1992; hereafter LP92) indicates that their equation can overestimate soil evaporation when the atmospheric resistance is low and underestimate soil evaporation when the soil is dry. Using a synthetic inversion experiment, we demonstrated that using inverted soil resistance data from field measurements to derive empirical soil resistance formulations resulted in large uncertainty because (1) the inverted soil resistance data are always severely impacted by measurement error and (2) the derived empirical equation is very sensitive to the number of data points and the assumed functional form of the resistance. We expect the application of our new TBC in land models will provide a consistent representation for the diffusive tracer exchange at the soil–air interface.

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