Tesi: "Soil absorption"

1

Ward, Philip R. "Generation of water repellence in sands, and its amelioration by clay addition /". Adelaide, 1993. http://web4.library.adelaide.edu.au/theses/09PH/09phw262.pdf.

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2

Gusli, Sikstus. "Effect of methods of wetting and rainfall characteristics on crusting and hardsetting of a red-brown earth". Title page, abstract and table of contents only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phg982.pdf.

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Abstract (sommario):

Includes bibliographical references. The beneficial effects of tillage are often negated in Australian soils by poor aggregate structural stability. If irrigation or rain falls on exposed freshly tilled soil, crusting or harsetting often develops on drying. Rainfall intensity, kinetic energy, rate of wetting, antecedent water content and soil management history have been implicated in aggregate breakdown.

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3

Sandhu, Harjinder. "Sorption of lead and arsenic on soil components and effectiveness of phosphates for remediating lead and arsenic contaminated soils". Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1923.

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Thesis (Ph. D.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains xii, 170 p. : ill. (some col.). Includes abstract. Includes bibliographical references.

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4

Park, Gi-hyeon. "Spatial and temporal patterns in soil moisture variations in Oklahoma and its comparison with ETA Model". Thesis, The University of Arizona, 2000. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0057_m_sip1_w.pdf&type=application/pdf.

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5

Ward, Philip R. "Generation of water repellence in sands, and its amelioration by clay addition / Philip R. Ward". Thesis, Adelaide, 1993. http://hdl.handle.net/2440/21659.

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6

Fu, Yong 1948. "Solid activity coefficients of phosphate adsorbed by soil". Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276722.

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Abstract (sommario):

The data of 14 soils were used to compute the ion activity product (IAP), the ratio of the ion activity product and to the solubility product (Ksp) of the pure minerals (IAP/Ksp) and to estimate the solid activity coefficients (SAC) of the soil components. The value of IAP and SAC of AlPO4 differs from soil to soil and increases with increasing P added to soil in acid soils and for calcium phosphate in basic soils. Magnesium apparently did not cause P adsorption or precipitation in the soils studied. The SAC of aluminum phosphate ranged from 10 to 10000 in acid soils. The mole fraction of the total phosphate in soil seemed to be a more satisfactory basis for calculating the concentration of the solid phase than was measurements of the available phosphate.

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7

Xiao, Baohua. "The effects of soil organic matter heterogeneity on equilibrium sorption by soils and sediments /". Philadelphia, Pa. : Drexel University, 2004. http://dspace.library.drexel.edu/handle/1860/305.

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8

Killen, Mark Albert. "A physically based analytical model to predict infiltration under surge irrigation". Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184379.

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A significant advantage attributed to surge flow irrigation is that for the same volume of water applied the stream will advance farther along the furrow than with continuous flow. This potentially will reduce runoff and deep percolation which will improve uniformity and application efficiency where this advance phenomenon holds. The mechanism for improvement in advance time has generally been ascribed to surface sealing and surface layer consolidation. However, these phenomena do not satisfactorily explain improved advance times in sandy soils. Widely used infiltration equations which require the determination of empirical coefficients are unsatisfactory as predictors of infiltration conditions of intermittent wetting. The Green-Ampt model and a simple redistribution model are combined into an analytical model to predict infiltration under surge irrigation. The model results are compared to infiltration tests on soil columns of three soils of different soil textures. Also the model and the experimental results from the soil columns are compared to predictions made by two numerical solutions of the Richard's equation. One of the numerical models includes the effect of hysteresis by the use of Mualem's model to predict the variation of moisture content with potential, the other numerical model neglects the effect of hysteresis. A comparison of the analytical and the numerical models shows good agreement in their predictions for the soils and surge cycles tested. A comparison of predictions made by all three models shows good correlation to the experimental results. Although the number of tests done on the analytical model were limited it appears to be nearly as good a predictor of infiltration as the numerical models. The greatest strength of the analytical model is that while the numerical models took many hours to do a single run, the analytical model took only a few minutes. Both model and experimental results indicate that there was no reduction in infiltration rates or volumes infiltrated with intermittent as compared to continuous wetting. Thus the reduction in hydraulic gradient is not a factor in the reduced infiltration observed by others.

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9

Don-Pedro, Esther A. "The effects of soil properties and clay minerals on the bioremediation of soils contaminated with pentachlorophenol". Akron, OH : University of Akron, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1126632988.

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Thesis (M.S.)--University of Akron, Dept. of Geology, 2005.
"August, 2005." Title from electronic thesis title page (viewed 11/29/2005) Advisor, Annabelle Foss; Committee members, Teresa Cutright, Ira Sasowsky; Department Chair, John Szabo; Dean of the College, Charles B. Monroe; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.

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10

Sekhon, Bharpoor Singh. "Modeling of soil phosphorus sorption and control of phosphorus pollution with acid mine drainage floc". Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2530.

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Thesis (Ph. D.)--West Virginia University, 2002.
Title from document title page. Document formatted into pages; contains xiv, 210 p. : ill. (some col.). Includes abstract. Includes bibliographical references.

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11

Wang, Yu-Hsing. "Attenuation in soils and non-linear dynamic effects". Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/19582.

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12

Miropolskiy, Reuven. "The effects of soil properties on the sorption of selected cephalosporin antibiotics". Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Fall2009/r_miropolskiy_120109.pdf.

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Thesis (M.S. in chemical engineering)--Washington State University, December 2009.
Title from PDF title page (viewed on Jan. 20, 2010). "Department of Chemical Engineering and Bioengineering." Includes bibliographical references (p. 63-65).

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13

Mewett, John University of Ballarat. "Electrokinetic remediation of arsenic contaminated soils". University of Ballarat, 2005. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/12797.

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"Arsenic is a common soil contaminant in Australia and worldwide. There is a need to find safe, effective and economic methods to deal with this problem. The soils used in this research were collected from central Victoria. They were contaminated with arsenic by historic gold mining activity or by past sheep dipping practices. This research investigated ten different leaching agents for their effects on three different arsenic contaminated soils. [...] Electrokinetic experiments were conducted on three arsenic contaminated soils. [...] The arsenic in these soils appears to be relatively stable and immobile under oxidising conditions. The soils had a high iron content which assists in the stabilisation of arsenic. This is beneficial with respect to the environmental impact of the arsenic contamination, however, it remains an obstacle to low cost electrokinetic remediation."
Masters of Applied Science

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14

Mewett, John. "Electrokinetic remediation of arsenic contaminated soils". Thesis, University of Ballarat, 2005. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/68354.

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Abstract (sommario):

"Arsenic is a common soil contaminant in Australia and worldwide. There is a need to find safe, effective and economic methods to deal with this problem. The soils used in this research were collected from central Victoria. They were contaminated with arsenic by historic gold mining activity or by past sheep dipping practices. This research investigated ten different leaching agents for their effects on three different arsenic contaminated soils. [...] Electrokinetic experiments were conducted on three arsenic contaminated soils. [...] The arsenic in these soils appears to be relatively stable and immobile under oxidising conditions. The soils had a high iron content which assists in the stabilisation of arsenic. This is beneficial with respect to the environmental impact of the arsenic contamination, however, it remains an obstacle to low cost electrokinetic remediation."
Masters of Applied Science

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15

Mewett, John. "Electrokinetic remediation of arsenic contaminated soils". University of Ballarat, 2005. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/14633.

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Abstract (sommario):

"Arsenic is a common soil contaminant in Australia and worldwide. There is a need to find safe, effective and economic methods to deal with this problem. The soils used in this research were collected from central Victoria. They were contaminated with arsenic by historic gold mining activity or by past sheep dipping practices. This research investigated ten different leaching agents for their effects on three different arsenic contaminated soils. [...] Electrokinetic experiments were conducted on three arsenic contaminated soils. [...] The arsenic in these soils appears to be relatively stable and immobile under oxidising conditions. The soils had a high iron content which assists in the stabilisation of arsenic. This is beneficial with respect to the environmental impact of the arsenic contamination, however, it remains an obstacle to low cost electrokinetic remediation."
Masters of Applied Science

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16

Robinson, Kevin G. "Influence of organic matter on the sorption and bioavailability of 2,4,6-trichloro-(¹⁴C)-phenol". Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-08082007-114313/.

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17

Forsling, Scott A. "Sorption and biodegradation of phenanthrene in soils". Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-11102009-020357/.

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18

Davis, James Hal 1956, e James Hal 1956 Davis. "Sorption and desorption of benzene and para-xylene on an unsaturated desert soil". Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/291366.

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A series of bench-scale experiments was carried out to determine the rate and efficiency with which benzene and p-xylene, components of gasoline, could be removed from an unsaturated soil by air stripping. Glass columns, 30 cm in length, were packed with soil and wetted to volumetric moisture contents of 10 and 18 percent. Air saturated with one of the volatile organic compounds (VOCs) was used to load the column. Clean air was used to strip the contaminant from the soil. Benzene and p-xylene concentrations in the soil water and air were reduced four orders of magnitude after a few hours (2-8) of stripping. Benzene was removed faster than p-xylene. Air flow was the rate-limiting step early in the stripping, however slow desorption from the soil became rate-limiting as the stripping progressed. As moisture content increased the rate of removal of both contaminants decreased.

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19

Hasan, Nazmul. "Adequacy of surface diffusion models to simulate nonequilibrium mass transfer in soils". Online access for everyone, 2008. http://www.dissertations.wsu.edu/Thesis/Summer2008/n_hasan_063008.pdf.

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20

Martin, Charlotte Anne. "Sorption and transport of selected nonionic surfactants in soil systems". Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/19118.

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21

Karagunduz, Ahmet. "Influence of surfactants on the sorption and transport of contaminants in saturated and unsatruated soils". Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/20745.

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22

McMahon, Claire Louise. "Characteristics and sorption properties of charcoal in soil with a specific study of the charcoal in an arid region soil of Western Australia". University of Western Australia. School of Earth and Geographical Sciences, 2006. http://theses.library.uwa.edu.au/adt-WU2007.0007.

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[Truncated abstract] Fire creates charcoal from the partial burning of biomass which results in a biologically inert form of carbonaceous (non-living) organic matter that, once integrated into soil and sediments, can persist for long periods of time. Charcoal has a large surface area with a high sorptive capacity for organic and inorganic substances. As a repository for metal and non-metal elements charcoal has been given little, if any, attention in the fields of geochemistry, agriculture and environmental monitoring . . . Despite the differences in charcoal surface area, soil charcoal achieved nearly 100% sorption of 0.5 and 5 μg/g Au from 0.03 M NaCl and 0.01M Ca(NO3)2 solution, almost independent of solution pH. At low pH, charcoal sorbed between 10 and 60% of Cu with initial additions of 2 and 20 μg Cu/g. Similarly, between 15 and 40% of Zn was sorbed by charcoal with initial additions of 5 and 40 μg Zn/g. The role of surface area in sorption of elements by charcoal is clearly only one factor that is important. Charcoal aromatic and aliphatic chemical functional groups, which can be distinguished from other forms of organic matter through spectroscopic determination, are also important in charcoal’s capacity to sorb elements. Accumulation of Be, B, Na, Mg, Al, Si, K, Ca, Ti, Mn, Co, Ni, Cu, Se, Mo, Ba, Au and Pb (out of a range of 29 elements) in soil charcoal, above the concentrations in the matrix soil and plant reference charcoal, was confirmed by ICP-MS analysis. Concentrations of V, Mn, Co, Ni, Cu, Mo, Ba, Au, Pb and Bi were higher in soil charcoal than in values quoted for gossans and pisolites in the field area region (Smith and Perdrix, 1983). Higher values of Au in soil charcoal were associated with considerable amounts of included clay minerals and higher values of other elements including Mo, Mn and Fe.

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23

Niemeyer, Antje. "Prozessanalyse mit Hilfe von mathematischen und statistischen Methoden am Beispiel von Ad- und Desorption im Boden /". Aachen : Shaker, 2000. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=009102162&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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24

Jacinthe, Pierre-Andre. "Adsorption of the nitrification inhibitors nitrapyrin and dicyandiamide by soil humic substances". Virtual Press, 1990. http://liblink.bsu.edu/uhtbin/catkey/722445.

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Abstract (sommario):

Adsorption of the nitrification inhibitors dicyandiamide (DCD) and nitrapyrin (2-chloro-6(trichloromethyl)-pyridine) on humic acid (HA) and fulvic acid (FA) extracted from five Indiana soils was studied. Ten mg of HA or FA were suspended in aqueous solutions (10 ml) of either DCD (5,10, 20, 40 and 80 ug ml-1) or nitrapyrin (2,4,6,8,12 ug ml-1). The amount of nitrification inhibitor absorbed was evaluated after shaking the suspension of DCD for 48 h or nitrapyrin for 24 h. Infrared spectra of the nitrification inhibitor-humic material complexes were recorded. The results indicated that FA adsorbed more DCD than HA, and HA was a better adsorbent for nitrapyrin. Correlation between Freundlich K values and organic carbon content of HA and FA was not statistically significant, indicating a slight contribution of hydrophobic forces in the adsorption of DCD and nitrapyrin. The infrared spectra provided evidence that adsorption occurred predominantly through an ionic bonding mechanism involving the protonated amino group of DCD or the nitrogen of the pyridine ring of nitrapyrin and the negative functional groups of the humic materials.
Department of Natural Resources

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25

Holland, Jonathan Eddison. "Changes in soil physical properties under raised bed cropping /". Connect to thesis, 2006. http://eprints.unimelb.edu.au/archive/00002537.

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26

Taillon, Kate. "Modeling surface complexation relationships in forest and agricultural soil". Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82435.

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The adsorption behaviour of trace metals in soil may provide us with a way to more accurately predict and assess the toxicity of metals in the environment. This thesis reports efforts to apply surface complexation modeling to agricultural and forest soil and to relate model parameters to common soil properties. This study considered Ca, Cd, Cu, Pb and Zn but the methods here could be applied to other metals. In Chapter 2, the surface charge and adsorption behaviour of a set of Ap horizons was characterised using back-titration and batch adsorption techniques. With the objective of simplifying the application of the NICCA model to surface charge and cation adsorption in whole soils the parameters of the NICCA model were related to soil properties (Chapter 3). Four of the six surface charge parameters could be predicted from soil properties and this enabled me to reasonably predict the surface charge of a second group of soils from soil properties. These results suggest that it is possible to make reasonable predictions about the surface charge and adsorption behaviour of a given type of soil using some easily measurable soil properties and a set of generic NICCA adsorption parameters for that soil type. In Chapter 4 this idea is applied to the determination of lime requirement for the agricultural soils.

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27

Bergsten, Joshua. "Sorption and leaching characteristics of heavy metals in artificial soil". Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4617.

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Thesis (M.S.) University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 21, 2007) Includes bibliographical references.

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28

Brooks, George Patrick 1955. "Forced ventilation removal of chlorinated hydrocarbons in layered, unsaturated soil material: A laboratory evaluation". Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/276975.

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Helium tracer experiments were conducted to characterize conservative tracer behavior in a wedge-shaped lysimeter containing alternating layers of unsaturated silty sand, and clay loam. Experiments were conducted with trichloroethylene and 1,1,1-trichloroethane to determine if air stripping in unsaturated soil could be characterized by mass transfer from the sorbed to the liquid to the vapor phase. Batch experiments were conducted to measure liquid--vapor mass transfer. Solid-liquid-vapor mass transfer was characterized by measuring the vapor phase re-equilibration after the air stripping experiment. The Discrete State Compartment model was used to simulate a conservative gas tracer. The results were compared to the helium tracer. Liquid-vapor, and solid-liquid-vapor mass transfer were modeled by fitting simulated data to experimental data. The conservative tracer, and mass transfer models were combined to simulate air stripping in unsaturated soil.

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29

Shrestha, Suman Lal. "Fate and Transformation of a Conjugated Natural Hormone 17β-Estradiol-3-Glucuronide in Soil-Water Systems". Diss., North Dakota State University, 2011. https://hdl.handle.net/10365/29317.

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The objectives of the study were to investigate the sorption and degradation of a glucuronide conjugated natural hormone, 17β-estradio1-3-glucuronide (E2-3G), and its estrogenic metabolites in soil-water systems. Radiolabeled E2-3G was first synthesized in the laboratory. Soil-water batch experiments were then conducted using natural and sterilized topsoil (0-6 cm) and subsoil (18-24 cm) with the radiolabeled E2-3G to investigate the effects of soil organic matter content and microbial activity. The aqueous dissipation of 14C in the batch experiments followed a biphasic pattern with an initial rapid dissipation phase followed by a second slower phase. Significant differences in total aqueous 14C dissipation were observed for the different initial concentrations for both soils, with greater persistence of intact E2-3G at higher initial concentrations.
National Science Foundation [Grant No. 0730492]

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30

Shrestha, Suman Lal. "Fate and Transformation of a Conjugated Natural Hormone 17?-Estradiol-3-Glucuronide in Soil-Water Systems". Diss., North Dakota State University, 2011. https://hdl.handle.net/10365/29317.

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Abstract (sommario):

The objectives of the study were to investigate the sorption and degradation of a glucuronide conjugated natural hormone, 17?-estradio1-3-glucuronide (E2-3G), and its estrogenic metabolites in soil-water systems. Radiolabeled E2-3G was first synthesized in the laboratory. Soil-water batch experiments were then conducted using natural and sterilized topsoil (0-6 cm) and subsoil (18-24 cm) with the radiolabeled E2-3G to investigate the effects of soil organic matter content and microbial activity. The aqueous dissipation of 14C in the batch experiments followed a biphasic pattern with an initial rapid dissipation phase followed by a second slower phase. Significant differences in total aqueous 14C dissipation were observed for the different initial concentrations for both soils, with greater persistence of intact E2-3G at higher initial concentrations.
National Science Foundation [Grant No. 0730492]

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31

Milham, Paul J. "The behaviour of cadmium in soil". View thesis, 2008. http://handle.uws.edu.au:8081/1959.7/39519.

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Thesis (Ph.D.) -- University of Western Sydney, 2008.
A thesis submitted to the University of Western Sydney, College of Health and Science, Centre for Plant and Food Science, in fulfilment of the requirements for the degree of Doctor of Philosophy. Includes bibliographical references.

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32

Ekanayake, Jagath C. "Soil water movement through swelling soils". Lincoln University, 1990. http://hdl.handle.net/10182/1761.

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The present work is a contribution to description and understanding of the distribution and movement of water in swelling soils. In order to investigate the moisture distribution in swelling soils a detailed knowledge of volume change properties, flow characteristics and total potential of water in the soil is essential. Therefore, a possible volume change mechanism is first described by dividing the swelling soils into four categories and volume change of a swelling soil is measured under different overburden pressures. The measured and calculated (from volume change data) overburden potential components are used to check the validity of the derivation of a load factor, ∝. Moisture diffusivity in swelling soil under different overburden pressures is measured using Gardner's (1956) outflow method. Behaviour of equilibrium moisture profiles in swelling soils is theoretically explained, solving the differential equation by considering the physical variation of individual soil properties with moisture content and overburden pressure. Using the measured volume change data and moisture potentials under various overburden pressures, the behaviour of possible moisture profiles are described at equilibrium and under steady vertical flows in swelling soils. It is shown that high overburden pressures lead to soil water behaviour quite different from any previously reported.

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33

Yiannakakis, Alexandros Emmanuel 1959. "Adsorption/desorption of phenols on the Pima clay loam soil". Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276709.

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Abstract (sommario):

A linear distribution isotherm described the sorption/desorption of four phenols on the Pima clay loam soil. The linear distribution coefficients for 2,4-dichlorophenol, 2-chlorophenol, phenol and 2,4,6-trichlorophenol were 3.61, 2.93, 0.87, and 0.79. Ionization of the phenols affected their relative distribution order. Hydrogen bonding of phenols to exposed mineral sites accounted for the greater measured sorption than was predicted. The effect of solid concentration on the distribution of phenols was tested over a 10-fold soil/solution range. When a log transformation was performed on the data, a highly significant inverse relationship existed between the distribution of phenols and the soil/solution ratio. A 3-fold increase in the dissolved organic carbon in solution was associated with the decrease in the distribution coefficient. A 3-fold increase in the fraction organic carbon in the soil occurred when dry sludge solids were added to the Pima soil. A substantial increase in the dissolved organic carbon in solution was associated with the addition of sludge solids to the soil. (Abstract shortened with permission of author.)

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34

Milham, Paul J. "The behaviour of cadmium in soil". Thesis, View thesis, 2008. http://handle.uws.edu.au:8081/1959.7/39519.

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Abstract (sommario):

Long-term low-level ingestion of cadmium (Cd) causes human health problems, and in Australia, vegetables supply ~40% of the Cd in the typical diet. Plants take up Cd from the soil; however, the uptake is poorly predicted by simple soil tests, such as the total concentration of Cd (Cdt). Therefore, a greater understanding of Cd behaviour in soils is needed to improve the prediction of Cd uptake by plants and open a new path to minimise the risks for human health. The objectives of the research in this thesis were to: identify key soil properties affecting Cd behaviour, identify/develop selective methods to measure them, and to formulate a conceptual model of Cd partitioning. These objectives were based on the hypothesis that empirical modelling informed by a better understanding of Cd chemistry would accurately describe Cd partitioning in soil. To test the hypothesis, the key properties were measured on soils from the peri-urban fringe of Greater Sydney (n = 41) and a series of models of increasing complexity were fitted to the data. A model with three explanatory variables— log10 Cdt, pH and log10 ECEC (effective cation exchange capacity)—explained 94.6% of variation in log10 CdCa (the concentration of Cd in solution in a suspension of soil in 10 mM CaCl2), which strongly supported the hypothesis. The study also indicated that the explanatory variables, Cdt, pH and ECEC, may describe Cd behaviour in many soils, and that for these general models, partition coefficients, such as log10 (Cdt/CdCa), are unsuitable dependent variables. The preceding model used Cdt as an explanatory variable, notwithstanding that labile Cd (CdE) was mechanistically preferable. However, CdE can only be measured using isotopic techniques: a requirement that has constrained the evaluation of CdE as an index of Cd behaviour and bioavailability. Therefore, a simple proxy measure of CdE was investigated. The literature indicated that solutions of chloride salts might selectively extract CdE, and Cd extracted into 1 M NH4Cl (CdNH4Cl) was compared with CdE measured by stable isotope dilution ICPMS. For 23 soils from the partitioning study, 1 M NH4Cl failed to completely extract CdE, unless the pH was less than 5. The cause(s) of this effect will be investigated with the aim of developing a universally applicable measure of CdE that does not require isotopic measurements. All models of Cd uptake by plants rely on soil properties measured on homogenised samples, although the distribution and bioavailability of Cd vary spatially in the field. Were such variability to increase at the micro-scale, its effects could erode the accuracy with which models could predict Cd behaviour and uptake. Consequently, I tested whether the distribution of Cd could be mapped by using synchrotron micro-x-ray fluorescence spectroscopy (micro- XRFS): the most sensitive method of observation. The soils examined contained 0.3–6.4 mg Cd/kg, i.e. were typical agricultural soils, and one was spiked to ~100 mg Cd/kg. Micro-XRFS mapped the Cd in the spiked soil, and in one particle in the other soils. For typical agricultural soils, the sensitivity realised in this study would have been sufficient to characterise the average Cd binding site, but fell at least 10-fold below that needed to map the Cd distribution in them. The research satisfied the objectives, advanced knowledge of Cd behaviour in soils, and provided new research leads. These leads include the possibility of developing general models of Cd partitioning in soils, derivatives of which may predict Cd uptake by plants. The accuracy of these models may be strengthened by the use of CdE as an explanatory variable, but may be weakened by the effects of in situ variation in the distribution of Cd. The benefits to human health of agricultural practices that decrease dietary Cd justify continuation of research to develop models that accurately predict Cd uptake by plants.

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35

Reed, Stewart T. "Copper adsorption/desorption characteristics on copper amended soils". Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06062008-171512/.

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36

Mersie, Wondimagegnehu. "Selectivity and soil behavior of chlorsulfuron". Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/53563.

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Response of barley (Hordeum vulgare L.) and wheat (Triticum aestivum L.) to root-applied chlorsulfuron (2-chloro N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl) amino] carbonyl] benzenesulfonamide), a herbicide for use in small grains, was investigated. The results showed that, although wheat roots take up more chlorsulfuron than barley roots, barley was less tolerant to chlorsulfuron and chlorsulfuron was more mobile in barley. This study indicated that difference in uptake or translocation cannot explain the differential response of the two species to root-applied chlorsulfuron. In an interaction study, significant chlorsulfuron antagonism on ryegrass (Lolium multiflorum Lam.) control by diclofop {(±)[-2-[4-(2,4-dichlorophenoxy) phenoxy) propanoic acid} was observed. Greenhouse experiments showed that the tolerance of corn (Zea mays L.) to chlorsulfuron and metsulfuron (2-[[[[(4-methoxy-6-methyl-l,3,5-triazin- -2-yl) amino] carbonyl] amino] sulfonyl] benzoic acid) was greatly increased by seed dressing with the herbicide safener NA (1,8-naphthalic anhydride). The soil behavior of chlorsulfuron was studied in the field, greenhouse and laboratory. In the field, corn adequately tolerated soil residues present 10 months following postemergence application of chlorsulfuron at 10 to 120 g/ha. However, at the same site and rates, residues from chlorsulfuron injured corn when sampled 2 months after application. In laboratory studies chlorsulfuron was moderately adsorbed by organic matter but showed low affinity to clay. R_f values calculated from soil thin-layer chromatography closely correlated with the mobility of chlorsulfuron leached with 16.8 cm of water over a 14-day period in hand-packed soil columns. In the soil thin-layer chromatography, chlorsulfuron mobility was positively and negatively correlated with pH and organic matter, respectively. The results indicated that chlorsulfuron could be mobile in low organic matter and non-acidic soils. The relationship of chlorsulfuron phytotoxicity to soil physical and chemical properties was also evaluated. Organic matter was inversely related to chlorsulfuron phytotoxicity while no such relationship to clay content was observed. The adsorption of chlorsulfuron decreased with increasing soil pH whereas desorption was greater at alkaline pH.
Ph. D.

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37

Dikinya, Oagile. "The effects of self-filtration on saturated hydraulic conductivity in sodic sandy soils /". Connect to this title, 2006. http://theses.library.uwa.edu.au/adt-WU2007.0051.

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38

Esfandiari, Baiat Mansour, of Western Sydney Hawkesbury University, of Science Technology and Agriculture Faculty e School of Agriculture and Rural Development. "Evaluation of furrow irrigation models for south-east Australia". THESIS_FSTA_ARD_EsfandiariBaiat_M.xml, 1997. http://handle.uws.edu.au:8081/1959.7/739.

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The overall objective of this study was to evaluate the performance of selected furrow irrigation models for field conditions in south-east Australia. The other important aspects which were examined during this study include: developing a methodology for estimating of infiltrating characteristics, assessing the applicability of the Manning and other similar equations for flows in furrow irrigation, investigating the variation of shape factor during irrigation developing methodology for estimation of recession time and exploring the sensitivity of the models to the input parameters. Field experiments were conducted at Walla Park in northern N.S.W. and on two selected paddocks at the University Farm, Richmond, in western Sydney,Australia, over a period of three years. The validity of the assumption that the shape factor of advancing water front during furrow irrigation varies between 0.7 and 0.8 was investigated using field data collected from irrigation events monitored in the study. It was found that the average values of the shape factor varied from 0.96 to 1.80 at Walla Park site, from 0.56 to 0.80 at Field Services unit paddock site and from 0.78 to 0.84 at Horticulture Farm paddock site. The value of shape factor was affected by uniformity of furrow cross section along the length, the value and uniformity of furrow slope, furrow length and infiltration characteristics of soil. This means it is difficult to recommend a typical value for the shape factor for a given field situation.The performance of the models for prediction of advance and recession characteristics and runoff were evaluated using different indices of performance. In general, it was found that the Walker-HD and ZI model was the most satisfactory for the field conditions encountered in this study. This finding can provide a basis for initiating work on developing design criteria and management strategies for furrow irrigation in south-east Australia.
Doctor of Philosophy (PhD)

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39

Ochwoh, Victor Akangah. "The dynamics of phosphorus extractability, adsorption, and desorption rates as influenced by phosphorus applications and incubation times". Thesis, University of Pretoria, 2002. http://hdl.handle.net/2263/28636.

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In a study to investigate the fate of the applied P in soils, a red-sandy clayey soil (Ferric Luvisols) from Rustenburg (high P fixing) and a red-sandy loam soil (Ferric Acrisols) from Loskop (low P fixing) were used. Sequential P fractionations were used to determine the content of the different P pools to show which pool the applied P was transformed to. The soils treatments consisted of different Prates (0, 25, 50, 100, 150, and 200 mg kg-1), and incubation periods (1, 60, 120, 180, and 240 days) under a laboratory conditions. The sequential P fractionation procedure consisted of extraction with hydrous ferric oxide in a dialysis membrane tube (DMT-HFO), 0.5M NaHC03, O.1M NaOH-P, 1.0M HCI, concentrated HCI, and concentrated H2S04 + H2O2. Approximately 30 to 60 % of the added P were transformed into less labile P pools within one day and 80-90 % after 60 days. This transformation was faster in the Rustenburg than in the Loskop soil showing a higher P fixation capacity. A major part of the P transformation was to the -OH-P1 pool with a recovery of about 30%. In the second experiment an attempt was made to determine P desorption rates by successive DMT-HFO extractions (1, 7, 14, 28, and 56 days) after the transformations of the applied P. This was followed by the sequential extractions to determine the changes and distribution of the added P into different P pools as well as which pools the P was des orbed from. The Rustenburg and Loskop soils were treated to different Prates (0, 25, 50, 100, and 200 mg P kg-1) and incubation periods (1, 120, and 240 days). The cumulative DMT -HFO extraction curves for 56 days showed that desorption could continue for a much longer period. This property is important in the economical management of fertilizer applications rates. Results showed the transformations and distribution of the applied P during incubation periods and proved that all the stable soil P pools contributed to the labile P pool by different proportions after prolonged successive DMT-HFO extractions. Although Rustenburg soil is considered a high P fixing soil, the P release rates under laboratory conditions were high enough to meet the requirements of cotton and tobacco crops. Root systems of these crops do not exploit 100 % soil volume as this laboratory method, which could explain why these crops experience P deficiencies. It is envisage that by using this method the P releasing properties of a soil could be used to develop a P desorption model to determine how much extractable P, with a specific extractant, in a particular soil, should be available at the beginning of a growing season to sustain a high enough P releasing rate to meet the requirements of a certain crop up to the end of the growing season. To do this, a model to describe root development that represents the percentage of the soil exploited P desorption rates that simulate P uptake by plant roots will be necessary.
Thesis (DPhil (Plant Production: Horticulture))--University of Pretoria, 2006.
Plant Production and Soil Science
unrestricted

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40

Wang, Guohui. "Sorption, desorption reversibility of polycyclic aromatic hydrocarbons (PAHs) in soils and carbonaceous materials". kostenfrei, 2008. http://d-nb.info/988782308/34.

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41

Bryson, Autumn Leah. "Sulfate sorption of acidified forest soils in the Otter Creek Wilderness area". Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4900.

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Thesis (M.S.)--West Virginia University, 2006.
Title from document title page. Document formatted into pages; contains vi, 36 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references (p. 31-36).

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42

Kothawala, Dolly N. "Controls on the soil solution partitioning of dissolved organic carbon and nitrogen in the mineral horizons of forested soils". Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115565.

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Note:
The soil-solution partitioning of dissolved organic carbon (DOC) withinmineral soil horizons is primarily controlled by processes of adsorption and desorption. These abiotic processes largely occur within a short equilibration time of seconds to minutes, which generally occur faster than microbial processes. To characterise the adsorption of DOC to mineral soils, I used the Langmuir adsorption isotherm, which holds several advantages to the commonly used linear initial mass (IM) isotherm. One advantage to using the Langmuir isotherm is anestimation of the maximum DOC adsorption capacity (Qmax). The Qmax estimates the number of remaining DOC binding sites available on the mineral soil particle surfaces. I modified the traditional Langmuir isotherm in order to estimate the DOC desorption potential of native soil organic matter (SOC).[...]
Le partitionnement entre les solutions de sols du carbone organiquedissous (COD) dans les horizons des sols minéraux est essentiellement contrôle par les processus d'adsorption et de désorption. Ces processus abiotiques se déroulent normalement dans un bref temps d'équilibration variant de quelques secondes a quelques minutes, ce qui est en général plus rapide que les processus microbiens. Pour caractériser Fadsorption de COD aux sols minéraux, nous avons utilise l'isotherme d'adsorption de Langmuir. Cette isotherme présente plusieurs avantages par rapport a Fisotherme de masses initiales (IM) linéaires couramment utilisée, en particulier F estimation de la capacité d'adsorption maximale du COD (Qmax). Le Qmax estime le nombre de sites de liaison de COD restants a la surface du sol minéral. Nous avons aussi modifie Fisotherme de Langmuir traditionnelle afin d'évaluer le potentiel de désorption de COD de la matière organique du sol indigène (MOS).[...]

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43

Kothawala, Dolly N. 1972. "Controls on the soil solution partitioning of dissolved organic carbon and nitrogen in the mineral horizons of forested soils". Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115858.

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The soil-solution partitioning of dissolved organic carbon (DOC) within mineral soil horizons is primarily controlled by processes of adsorption and desorption. These abiotic processes largely occur within a short equilibration time of seconds to minutes, which generally occur faster than microbial processes. To characterise the adsorption of DOC to mineral soils, I used the Langmuir adsorption isotherm, which holds several advantages to the commonly used linear initial mass (IM) isotherm. One advantage to using the Langmuir isotherm is an estimation of the maximum DOC adsorption capacity (Qmax). The Qmax estimates the number of remaining DOC binding sites available on the mineral soil particle surfaces. I modified the traditional Langmuir isotherm in order to estimate the DOC desorption potential of native soil organic matter (SOC).
Sorption characteristics were derived for a broad range of52 mineral soils collected from 17 soil profiles spanning across Canada from British Columbia to Quebec. Mineral horizons with the greatest Qmax included the Fe-enriched B horizons of acidic Podzols and Volcanic soils, followed by B horizons not enriched in Fe, followed by A and C horizons. Podzol B horizons were distinct from all other horizons due to significantly higher desorption potential. Soil properties predicting the adsorption characteristics of DOC also predicted the adsorption characteristics of dissolved organic nitrogen (DON). Adsorption of DOC and DON was tightly coupled (R 2 = 0.86), however the ratio of DOC:DON in the final equilibrium solution lowered for 48 out of 52 minerals horizons. These results suggest that DON may be slightly more mobile than DOC.
A short-term (32 day) incubation was perform to establish the fate of indigenous soil C, relative to newly adsorbed soil C to four mineral soils with different adsorption characteristics. Soil columns were leached periodically and sampled for DOC and CO2 production. Two Fe-enriched mineral horizons with high adsorption capacity released low amounts of old SOC, yet released almost all of the newly adsorbed SOC. In contrast, two B horizons without Fe-enrichment released greater amounts of old SOC, and retained a greater fraction of the newly adsorbed SOC than the Fe-enriched horizons. These results identify a contrast between the fate of indigenous and newly adsorbed SOC on mineral soils with differing Qmax.
The final component of this study examined changes to the molecular structure of DOC after equilibration with mineral soils. Multiple techniques were used to assess changes in the molecular composition of DOC, including the analysis of aromatic content by specific UV absorbance (SUVA) and fluorescence spectroscopy, analysis of molecular weight distribution (MWD) with high performance size exclusion chromatography (HPSEC) and functional group analysis with Fourier transform infra-red spectroscopy (FTIR). The solution phase DOC generally showed a reduced aromatic content, along with the removal of organic compounds with carboxyl groups. The MWD of DOC was reduced after equilibration to mineral soils, and the reduction in average molecular weight was related to the Qmax of mineral soils.
The various components of this thesis have contributed to the overall understanding of controls on the adsorption of DOC and DON species to mineral soils of the Canadian temperate and boreal forest.

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44

Yusran, Fadly Hairannoor. "Soil organic matter decomposition : effects of organic matter addition on phosphorus dynamics in lateritic soils". University of Western Australia. School of Earth and Geographical Sciences, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0120.

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[Truncated abstract] Relationships between the persistence of organic matter added to soil, the dynamics of soil organic carbon (C) and phosphorus (P) were examined in four experiments on lateritic soils of Western Australia. The main objective was to quantify the release of P following organic matter application in soils which have high P adsorbing capacity. Another objective was to confirm that due to its recalcitrant materials, the effect of peat lasted longer in soil than other sources of organic matter in terms of increasing plant-available P fractions. Three experiments were conducted under glasshouse conditions for various lengths of time, with nine- to twelve-month incubations to investigate these hypotheses. As expected, organic matter with lower C:N ratios than peat (lucerne hay) decomposed more rapidly compared with peat, and the most active mineralisation took place within the first three months of incubation. Soil organic-C (extracted by 0.5 M K2SO4) had a significant positive correlation with P extracted with 0.5 M NaHCO pH 8.53. For a higher application rate (120 ton ha-1), peat was better than wheat straw and lucerne hay in increasing extractable bicarbonate-P concentrations in soil, especially at incubation times up to 12 months. Throughout the experiment, peat was associated with a steady increase in all parameters measured. In contrast to peat, nutrient release from lucerne hay and wheat straw was rapid and diminished over time. There was a tendency for organic-C (either in the form of total extractable organic-C or microbial biomass-C) to steadily increase in soil with added peat throughout the experiment. Unlike wheat straw and lucerne hay, extractable organic-C from peat remained in soil and there was less C loss in the form of respiration. Therefore, peat persisted and sequestered C to the soil system for a longer time than the other source of organic matter. Freshly added organic matter was expected to have a greater influence on P transformation from adsorbed forms in lateritic soils than existing soil organic matter. By removing the existing soil organic matter, the effect of freshly applied organic matter can be determine separately from that of the existing soil organic matter for a similar organic-C content. In order to do this, some soil samples were combusted up to 450° C to eliminate inherent soil organic matter. The release of P was greater when organic-C from fresh organic matter was applied to combusted soils than in uncombusted soils that contained the existing soil organic matter. The exception only applied for parameters related to soil micro-organisms such as biomass-C and phosphatase. For such parameters, new soil organic matter did not create conditions favourable for organisms to increase in activity despite the abundance of organic matter available. More non-extractable-P was formed in combusted soils compared to bicarbonate-P and it contributed to more than 50% of total-P. As for the first experiment, peat also showed a constant effect in increasing bicarbonate extractable-P in the soil

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45

Weerasinghe, Vithanage Primali Anuruddhika. "Near infrared absorption for soil water measurement development and evaluation of a cost-saving, maintenance-free sensor". Beuren Stuttgart Grauer, 2007. http://d-nb.info/989986799/04.

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46

Nandihalli, Ujjanagouda B. "Toxicity, absorption, and traslocation of soil and foliar imazaquin in yellow (Cyperus esculentus) and purple (C.rotundus) nutsedge /". The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487323583619954.

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47

Mon, Jarai. "Sorption and its effects on transport of organic dyes and cesium in soils". Online access for everyone, 2004. http://www.dissertations.wsu.edu/Dissertations/Fall2004/j%5Fmon%5F121504.pdf.

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48

Aylmore, Lance Arthur Graham. "Sorption and transport processes in relation to soil structure, water retention, solute mobility and water uptake by plant roots". Title page, table of contents and summary only, 2002. http://web4.library.adelaide.edu.au/theses/09SD/09sda979.pdf.

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"April, 2002" Includes bibliographical references and Publications list (leaves 22-30) V. 1. nos.1-50 -- v. 2. nos. 51-105 "Selected research publications submitted to the University of Adelaide for the degree of Doctor of Science."

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49

Loganathan, Vijay Anand Clement Prabhakar Feng Yucheng. "Effects of sorption and desorption on bioavailbility of atrazine in soils amended with crop residue derived char". Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Summer/Theses/LOGANATHAN_VIJAY-ANAND_27.pdf.

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50

Aufdenkampe, Anthony Keith. "The role of sorptive processes in the organic carbon and nitrogen cycles of the Amazon River Basin /". Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/10968.

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Tesi sul tema "Soil absorption"

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