Journal articles: 'Soils Soil chemistry. Soil mineralogy'

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Fang, Qian, Hanlie Hong, Lulu Zhao, Stephanie Kukolich, Ke Yin, and Chaowen Wang. "Visible and Near-Infrared Reflectance Spectroscopy for Investigating Soil Mineralogy: A Review." Journal of Spectroscopy 2018 (2018): 1–14. http://dx.doi.org/10.1155/2018/3168974.

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Clay minerals are the most reactive and important inorganic components in soils, but soil mineralogy classifies as a minor topic in soil sciences. Revisiting soil mineralogy has been gradually required. Clay minerals in soils are more complex and less well crystallized than those in sedimentary rocks, and thus, they display more complicated X-ray diffraction (XRD) patterns. Traditional characterization methods such as XRD are usually expensive and time-consuming, and they are therefore inappropriate for large datasets, whereas visible and near-infrared reflectance spectroscopy (VNIR) is a quick, cost-efficient, and nondestructive technique for analyzing soil mineralogic properties of large datasets. The main objectives of this review are to bring readers up to date with information and understanding of VNIR as it relates to soil mineralogy and attracts more attention from a wide variety of readers to revisit soil mineralogy. We begin our review with a description of fundamentals of VNIR. We then review common methods to process soil VNIR spectra and summary spectral features of soil minerals with particular attention to those <2 μm fractions. We further critically review applications of chemometric methods and related model building in spectroscopic soil mineral studies. We then compare spectral measurement with multivariate calibration methods, and we suggest that they both produce excellent results depending on the situation. Finally, we suggest a few avenues of future research, including the development of theoretical calibrations of VNIR more suitable for various soil samples worldwide, better elucidation of clay mineral-soil organic carbon (SOC) interactions, and building the concept of integrated soil mapping through combined information (e.g., mineral composition, soil organic matter-SOM, SOC, pH, and moisture).

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Marchuk, Alla, Pichu Rengasamy, and Ann McNeill. "Influence of organic matter, clay mineralogy, and pH on the effects of CROSS on soil structure is related to the zeta potential of the dispersed clay." Soil Research 51, no. 1 (2013): 34. http://dx.doi.org/10.1071/sr13012.

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The high proportion of adsorbed monovalent cations in soils in relation to divalent cations affects soil structural stability in salt-affected soils. Cationic effects on soil structure depend on the ionic strength of the soil solution. The relationships between CROSS (cation ratio of soil structural stability) and the threshold electrolyte concentration (TEC) required for the prevention of soil structural problems vary widely for individual soils even within a soil class, usually attributed to variations in clay mineralogy, organic matter, and pH. The objective of the present study was to test the hypothesis that clay dispersion influenced by CROSS values depends on the unique association of soil components, including clay and organic matter, in each soil affecting the net charge available for clay–water interactions. Experiments using four soils differing in clay mineralogy and organic carbon showed that clay dispersion at comparable CROSS values depended on the net charge (measured as negative zeta potential) of dispersed clays rather than the charge attributed to the clay mineralogy and/or organic matter. The effect of pH on clay dispersion was also dependent on its influence on the net charge. Treating the soils with NaOH dissolved the organic carbon and increased the pH, thereby increasing the negative zeta potential and, hence, clay dispersion. Treatment with calgon (sodium hexametaphosphate) did not dissolve organic carbon significantly or increase the pH. However, the attachment of hexametaphosphate with six charges on each molecule greatly increased the negative zeta potential and clay dispersion. A high correlation (R2 = 0.72) was obtained between the relative clay content and relative zeta potential of all soils with different treatments, confirming the hypothesis that clay dispersion due to adsorbed cations depends on the net charge available for clay–water interactions. The distinctive way in which clay minerals and organic matter are associated and the changes in soil chemistry affecting the net charge cause the CROSS–TEC relationship to be unique for each soil.

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Mahaney, William C., Jessica Zippin, Michael W. Milner, et al. "Chemistry, mineralogy and microbiology of termite mound soil eaten by the chimpanzees of the Mahale Mountains, Western Tanzania." Journal of Tropical Ecology 15, no. 5 (1999): 565–88. http://dx.doi.org/10.1017/s0266467499001029.

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Subsamples of termite mound soil used by chimpanzees for geophagy, and topsoil never ingested by them, from the forest floor in the Mahale Mountains National Park, Tanzania, were analysed to determine the possible stimulus or stimuli for geophagy. The ingested samples have a dominant clay texture equivalent to a claystone, whereas the control samples are predominantly sandy clay loam or sandy loam, which indicates that particle size plays a significant role in soil selection for this behaviour. One potential function of the clays is to bind and adsorb toxins. Although both termite mound and control samples have similar alkaloid-binding capacities, they are in every case very high, with the majority of the samples being above 80%. The clay size material (<2 μm) contains metahalloysite and halloysite, the latter a hydrated aluminosilicate (Al2Si2O4·nH2O), present in the majority of both the termite mound soil and control soil samples.Metahalloysite, one of the principal ingredients found in the pharmaceutical Kaopectate™, is used to treat minor gastric ailments in humans. The soils commonly ingested could also function as antacids, as over half had pH values between 7.2 and 8.6. The mean concentrations of the majority of elements measured were greater in the termite mound soils than in the control soils. The termite mound soils had more filamentous bacteria, whereas the control soils contained greater numbers of unicellular bacteria and fungi.

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Oh, Tae-Min, Gye-Chun Cho, and Changho Lee. "Effect of Soil Mineralogy and Pore-Water Chemistry on the Electrical Resistivity of Saturated Soils." Journal of Geotechnical and Geoenvironmental Engineering 140, no. 11 (2014): 06014012. http://dx.doi.org/10.1061/(asce)gt.1943-5606.0001175.

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Cornu,, S., J. P. Ambrosi, Y. Lucas, and D. Fevrier. "A comparative study of the soil solution chemistry of two Amazonian forest soils (Central Amazonia, Brazil)." Hydrology and Earth System Sciences 1, no. 2 (1997): 313–24. http://dx.doi.org/10.5194/hess-1-313-1997.

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Abstract. Analyses of the chemical composition of rapidly percolating soil water were used to study the genesis of a shallow podzol in a Campinarana forest and a clayey ferralsol from a typical rainforest located in North Manaus (Amazonia, Brazil). The samples were collected in lysimeters and analysed for Ca2+, Na+, K+, NH4+, SO42-, NO3-, Fe, Si, and Al. A large percentage of the nutrients was recycled in the upper 40 centimetres of both soils. The soil water concentrations in nutrients were very similar for both environments but levels of Si, Fe and AI were higher in the podzol than in the ferralsol. In the podzolic environment, the waters were enriched in Si, Fe and AI when passing through the organic layer and the top 10 cm of the soil. The concentrations decreased between 10 and 40 cm depth due to variations in mineralogy of this soil. In the ferralsol, the Si concentrations increased considerably on reaching the soil top-horizons while small increases occurred for AI and Fe. Thermodynamic equilibrium calculations indicate that most of the dissolved AI and Fe in both soil environments were in the form of organometallic complexes and that the waters were under-saturated in respect to kaolinite and gibbsite.

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Poch, R. M., B. P. Thomas, R. W. Fitzpatrick, and R. H. Merry. "Micromorphological evidence for mineral weathering pathways in a coastal acid sulfate soil sequence with Mediterranean-type climate, South Australia." Soil Research 47, no. 4 (2009): 403. http://dx.doi.org/10.1071/sr07015.

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Soil micromorphology, using light microscopy and scanning electron microscopy (SEM), was used to describe detailed soil morphological and compositional changes and determine mineral weathering pathways in acid sulfate soils (ASS) from the following 2 contrasting coastal environments in Barker Inlet, South Australia: (i) a tidal mangrove forest with sulfidic material at St Kilda, and (ii) a former supratidal samphire area at Gillman that was drained in 1954 causing sulfuric material to form from sulfidic material. Pyrite framboids and cubes were identified in sulfidic material from both sites and are associated with sapric and hemic materials. Gypsum crystals, interpreted as a product of sulfide oxidation, were observed to have formed in lenticular voids within organic matter in the tidal mangrove soils at St Kilda. Sulfide oxidation was extensive in the drained soil at Gillman, evidenced by the formation of iron oxyhydroxide pseudomorphs (goethite crystallites and framboids) after pyrite and jarosite, and of gypsum crystals. Gypsum crystals occur where a local source of calcium such as shells or calcareous sand is present. Sporadic oxidation episodes are indicated by the formation of iron oxide and jarosite coatings around coarse biogenic voids. These observations indicate that mineral transformation pathways are strongly influenced by soil physico-chemical characteristics (i.e. oxidation rate, Eh, pH, soil solution chemistry, mineralogy, and spatial distribution of sulfides). This information has been used to illustrate the interrelationships of pyrite, carbonate, gypsum, jarosite, and organic matter and help predict soil evolution under changing hydro-geochemical, redoximorphic, and thermal conditions in soils from coastal environments.

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Boschi, Vanessa, and Jane K. Willenbring. "The effect of pH, organic ligand chemistry and mineralogy on the sorption of beryllium over time." Environmental Chemistry 13, no. 4 (2016): 711. http://dx.doi.org/10.1071/en15107.

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Environmental contextBeryllium is a toxic environmental contaminant but has many industrial and scientific applications. Our work explores the effects of soil composition on beryllium retention, focussing on organic matter, mineralogy and pH and concludes that phosphorus and sulfur oxides in addition to soil acidity are strong controls on beryllium mobility. These results aid in future predictions regarding the fate of beryllium in the environment. AbstractUnderstanding the chemical controls on beryllium sorption is fundamental when assessing its mobility as a pollutant and interpreting its concentration as a geochemical tracer of erosion, weathering and landscape surface stability. In order to evaluate the interactions of beryllium with soil- and aquatic-related materials, we selected model organic compounds and minerals to perform sorption experiments. The retention of beryllium by each of these compounds and minerals was evaluated over a pH range of 3–6 and at various equilibration times to determine which conditions allowed the greatest retention of beryllium. We conclude that most beryllium sorption occurred within 24h for both organic and mineral materials. However, equilibration required longer periods of time and was dependent on the solution pH and sorbent material. The pH exhibited a strong control on beryllium sorption with distribution coefficient (Kd) values increasing non-linearly with increasing pH. A system with a pH of 6 is likely to retain 79–2270% more beryllium than the same system at a pH of 4. Phosphonate retained the greatest amount of beryllium, with Kd values 2–30× greater than all other materials tested at a pH of 6. Therefore, soils containing larger amounts of phosphorus-bearing minerals could result in greater retention of beryllium relative to phosphorus-limited soils. Overall, soil composition, with an emphasis on phosphorus oxide content and pH, is an important property to consider when evaluating the capacity of a system to retain beryllium.

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Golchin, A., P. Clarke, JM Oades, and JO Skjemstad. "The effects of cultivation on the composition of organic-matter and structural stability of soils." Soil Research 33, no. 6 (1995): 975. http://dx.doi.org/10.1071/sr9950975.

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Soil samples were obtained from the surface horizons of five untilled sites and adjacent sites under short- and long-term cultivation. The soil samples were fractionated based on density and organic materials were concentrated in various fractions which enabled comparative chemical composition of the organic materials in cultivated and uncultivated sites by solid-state C-13 CP/MAS NMR spectroscopy. Changes in the nature of organic carbon with cultivation were different in different soils and resulted from variations in the chemistry of carbon inputs to the soils and a greater extent of decomposition of organic materials in cultivated soils. Differences in the chemical composition of organic carbon between cultivated and uncultivated soils resided mostly in organic materials occluded within aggregates, whereas the chemistry of organic matter associated with clay particles showed only small changes. The results indicate a faster decomposition of O-alkyl C in the cultivated soils. Wet aggregate stability, mechanically dispersible clay and modulus of rupture tests were used to assess the effects of cultivation on structural stability of soils. In four of five soils, the virgin sites and sites which had been under long-term pasture had a greater aggregate stability than the cultivated sites. Neither total organic matter nor total O-alkyl C content was closely correlated with aggregate stability, suggesting that only a part of soil carbon or carbohydrate is involved in aggregate stability. The fractions of carbon and O-alkyl C present in the form of particulate organic matter occluded within aggregates were better correlated with aggregate stability (r = 0.86** and 0.88**, respectively). Cultivation was not the dominant factor influencing water-dispersible clay across the range of soil types used in this study. The amount of dispersible clay was a function of total clay content and the percentage of clay dispersed was controlled by factors such as clay mineralogy, CaCO3 and organic matter content of soils. The tendency of different soils for hard-setting and crusting, as a result of structural collapse, was reflected in the modulus of rupture (MOR). The cultivated sites had significantly higher MOR than their non-tilled counterparts. The soils studied had different MOR due to differences in their physical and chemical properties.

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Stoker, Carol R., Jonathan Clarke, Susana O. L. Direito, et al. "Mineralogical, chemical, organic and microbial properties of subsurface soil cores from Mars Desert Research Station (Utah, USA): Phyllosilicate and sulfate analogues to Mars mission landing sites." International Journal of Astrobiology 10, no. 3 (2011): 269–89. http://dx.doi.org/10.1017/s1473550411000115.

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AbstractWe collected and analysed soil cores from four geologic units surrounding Mars Desert Research Station (MDRS) Utah, USA, including Mancos Shale, Dakota Sandstone, Morrison formation (Brushy Basin member) and Summerville formation. The area is an important geochemical and morphological analogue to terrains on Mars. Soils were analysed for mineralogy by a Terra X-ray diffractometer (XRD), a field version of the CheMin instrument on the Mars Science Laboratory (MSL) mission (2012 landing). Soluble ion chemistry, total organic content and identity and distribution of microbial populations were also determined. The Terra data reveal that Mancos and Morrison soils are rich in phyllosilicates similar to those observed on Mars from orbital measurements (montmorillonite, nontronite and illite). Evaporite minerals observed include gypsum, thenardite, polyhalite and calcite. Soil chemical analysis shows sulfate the dominant anion in all soils and SO4>>CO3, as on Mars. The cation pattern Na>Ca>Mg is seen in all soils except for the Summerville where Ca>Na. In all soils, SO4correlates with Na, suggesting sodium sulfates are the dominant phase. Oxidizable organics are low in all soils and range from a high of 0.7% in the Mancos samples to undetectable at a detection limit of 0.1% in the Morrison soils. Minerals rich in chromium and vanadium were identified in Morrison soils that result from diagenetic replacement of organic compounds. Depositional environment, geologic history and mineralogy all affect the ability to preserve and detect organic compounds. Subsurface biosphere populations were revealed to contain organisms from all three domains (Archaea, Bacteria and Eukarya) with cell density between 3.0×106and 1.8×107cells ml−1at the deepest depth. These measurements are analogous to data that could be obtained on future robotic or human Mars missions and results are relevant to the MSL mission that will investigate phyllosilicates on Mars.

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Marescotti, Pietro, Paola Comodi, Laura Crispini, Lara Gigli, Azzurra Zucchini, and Silvia Fornasaro. "Potentially Toxic Elements in Ultramafic Soils: A Study from Metamorphic Ophiolites of the Voltri Massif (Western Alps, Italy)." Minerals 9, no. 8 (2019): 502. http://dx.doi.org/10.3390/min9080502.

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Ultramafic soils are characterized by severe edaphic conditions induced by a low content of essential nutrients, an adverse Ca/Mg ratio, a low water-holding capacity, and high contents of geogenic potentially toxic elements (PTEs), in particular Cr, Ni, and Co. These metals commonly exceed the content limits set by environmental agencies and governments, representing serious environmental risks for ecosystems and human health. In alpine environments, ultramafic soils are characterized by modest thickness and poor horizon differentiation. Several studies on ultramafic soils have shown that their properties may be directly related to the characteristics of the parent rocks, but most of these studies deal with soil chemistry, metal availability, isotopic composition, and pedological characterization. The aim of this research is to investigate how much the geotectonic characteristics of ultramafic bedrocks, such as the degree of serpentinization, metamorphic imprint, and deformation, may affect the mineralogical and chemical variations of ultramafic soils, including the occurrence and potential mobility of the PTEs. Using a multiscale and multi-analytical approach, we fully characterize the properties and mineralogical composition of soil profiles with different ultramafic parent rocks, i.e., partially serpentinized peridotite, massive serpentinites, and foliated serpentinites, sampled within the Voltri Massif High Pressure–Low Temperature (HP–LT) metaophiolite (Western Alps, Italy). Our results, related to soils located at comparable latitude, altitude, landscape position, and pedological environment, outline that the degree of serpentinization, the metamorphic imprint, and the deformation history of the ultramafic parent rocks are key factors influencing soil evolution, mineralogy, and chemistry, as well as PTEs distribution and mobility. Moreover, this study shows that the high content of Cr, Ni, and Co in the studied ultramafic soils has to be considered of geogenic origin and highlights the need for new approaches and methods to obtain indications on the potential contamination of natural or anthropogenic soils.

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Janik, LJ, JO Skjemstad, and MD Raven. "Characterization and analysis of soils using mid-infrared partial least-squares .1. Correlations with XRF-determined major-element composition." Soil Research 33, no. 4 (1995): 621. http://dx.doi.org/10.1071/sr9950621.

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Chemical analysis is an important but often expensive and time-consuming step in the characterization of soils. Methods used for soil analysis ideally need to be rapid, accurate and relatively simple and infrared partial least squares (PLS) analysis is potentially one such method. Mid-infrared diffuse reflectance Fourier transform (DRIFT) spectra of powdered soils present the major mineralogical and organic components within each soil, relative to their concentrations. The theory indicates that experimentally derived soil properties may be correlated with the infrared spectra of some of these components, and the covariance between soil properties and spectra can then be modelled by PLS loadings and scores. Factors and scores can be derived independently for each Soil property using PLS-1, an extension of the more general PLS-2 method. This study evaluates the use of PLS-1 for the qualitative and quantitative study of soils, and in particular to classify the soil spectra and their associated major element chemistry by their PLS loadings and Scores. A subset of 100 soils, selected from a complete set of 298 samples from throughout eastern and southern Australia, was analysed by X-ray fluorescence (XRF) for major oxides as a calibration or training set to model the PLS loadings, scores and linear regression coefficients. Linear regressions resulted with R(2) values of 0 . 973-0 . 917 for XRF versus PLS predicted values for SiO2, Al2O3 and Fe2O3. Regressions for the other oxides, e.g. TiO2, MgO and CaO, were generally curved with a linear calibration giving severe underestimations at high concentrations. The PLS loadings and regression coefficients were then used to model the complete soil set to produce scores and concentration predictions for all the samples. The samples were plotted in bivariate score maps to give a visual representation of the spectral variability within the entire soil set. Samples were selected from the boundaries of the groups of soils in these maps for mineralogical characterization using X-ray diffraction (XRD) analysis. The XRD results confirmed the mineralogy obtained from the infrared spectra and PLS weight loadings. For this study, the depiction of the samples in the score maps was found to be of particular importance for demonstrating similarities in composition of the samples.

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Barbour, S. L., and N. Yang. "A review of the influence of clay–brine interactions on the geotechnical properties of Ca-montmorillonitic clayey soils from western Canada." Canadian Geotechnical Journal 30, no. 6 (1993): 920–34. http://dx.doi.org/10.1139/t93-090.

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Natural Ca-montmorillonite clay soils or engineered clay barriers in western Canada are often used to contain brine generated from the surface disposal of potash tailings or from drilling activities associated with the oil and gas industry. The performance of these barriers has ranged from excellent to poor. The influence of salt brines on the geotechnical properties of these soils has been recognized as a potentially important factor for some time. It has been well documented in the literature that the behavior of clayey soils is strongly influenced by physicochemical interactions between clay particles and pore-fluid chemistry; consequently, the properties of these soils are sensitive to changes in the electrolyte concentration of the pore fluid. An increase in the concentration of the pore fluid to the levels of a concentrated brine can cause significant changes in the geotechnical properties of the soil. In this paper, the impact of brine contamination on the geotechnical properties of two Ca-montmorillonitic clayey soils of glacial origin from western Canada is reviewed. The influence of clay–brine interactions on the index properties (liquid limit, plastic limit, plastic index, mineralogy, density, grain size, and compaction characteristics), mechanical properties (volume change and shear strength), and hydraulic properties (hydraulic conductivity) is described. A quantitative explanation for the changes that occur in the hydraulic and mechanical properties of these soils as a result of brine permeation is also provided. This explanation relates the changes in pore-fluid chemistry to changes in an effective physicochemical stress state. This approach may be used to predict the changes in hydraulic conductivity, volume, or shear strength of a clayey soil as a result of brine contamination. Key words : clay–brine interactions, diffuse double layer, hydraulic conductivity, soil structure, physicochemical.

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Pierzynski, G. M., T. J. Logan, and S. J. Traina. "Phosphorus Chemistry and Mineralogy in Excessively Fertilized Soils: Solubility Equilibria." Soil Science Society of America Journal 54, no. 6 (1990): 1589–95. http://dx.doi.org/10.2136/sssaj1990.03615995005400060013x.

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Baldotto, Marihus Altoé, Rafael Carvalho Muniz, Lílian Estrela Borges Baldotto, and Leonardo Barros Dobbss. "Root growth of Arabidopsis thaliana (L.) Heynh. treated with humic acids isolated from typical soils of Rio de Janeiro state, Brazil." Revista Ceres 58, no. 4 (2011): 504–11. http://dx.doi.org/10.1590/s0034-737x2011000400015.

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Humic substances isolated from soil organic matter had been used as stimulators of plant metabolism. Arabidopsis thaliana (L.) Heynh. with only five chromosomes, short cycle and size, is an important model to evaluate the physiological effects of these substances, which are qualitatively and quantitatively influenced by morphogenesis, mineralogy and chemistry of soils. The objective of this study was to evaluate the ambience effects on bioactivity of humic acids. A and B horizons of four typical soils of the North Fluminense were sampled. After isolation and purification, humic acids were applied to plants in increasing concentrations. The number and length of lateral roots and main root length were evaluated and, subsequently, the concentrations of maximum stimulation were determined by dose-response curves and regression equations. The results showed that more stable humic acids isolated from soil in less advanced stages of weathering, high activity clay and high base saturation resulted in better physiological stimulants for Arabidopsis.

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Laffan, MD, BK Daly, and JS Whitton. "Podzolized soils on hilly and steep land near Tennyson Inlet, Marlborough Sounds, New Zealand - Classification and relation to Landform, Slope and Altitude." Soil Research 24, no. 2 (1986): 115. http://dx.doi.org/10.1071/sr9860115.

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Eight soil profiles ranging in altitude from 30 m to 820 m at Tennyson Inlet in the Marlborough Sounds, New Zealand, are described, classified and discussed in terms of morphology, chemistry and clay mineralogy. The soils are formed from greywacke on forested hilly and steep land under a superhumid climate. Profiles show eluvial and/or illuvial features typical of podzols and podzolized soils. Within the study morphological, chemical and mineralogical properties show patterns in weathering, leaching and podzolization. Differences in weathering are related mainly to geomorphic history and topography. The most strongly weathered soils occur at altitudes below about 200 m where parent materials were probably inherited from Late Pleistocene interglacial or interstadial weathering. Less weathered soils occur at higher altitudes where parent materials were derived from widespread periglacial erosion during the last glaciation, and from periodic erosion during the Holocene. Weathering and also leaching is least on soils on very steep slopes (>38�) at altitudes above 200 m, where rejuvenation by slope movement has been more active than on less steep slopes. Patterns in weathering are clearly shown by clay mineralogy, with strongly weathered soils dominated by kaolinite, and less weathered soils dominated by vermiculite. Differences in podzolization are attributed mainly to greater effective rainfall, leaching and accumulation of amorphous minerals and mineral-organic complexes with increasing altitude. The combination of field and laboratory data shows that at altitudes below about 200-300 m profiles are relatively weakly podzolized, while podzolized soils and podzols occur at higher altitudes. Podzolization patterns are clearly shown by subsoil values of acid-oxalate and pyrophosphate Fe and Al, NaF, pH and P retention. The profile at highest altitude is dominated by smectite clays and the greyish-coloured solum is interpreted mainly as a relatively thick (80 cm) eluvial horizon resting directly on bedrock. Neither the New Zealand Genetic Classification nor Soil Taxonomy satisfactorily classifies all the soils.

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Egli, M., R. Zanelli, G. Kahr, A. Mirabella, and P. Fitze. "Soil evolution and development of the clay mineral assemblages of a Podzol and a Cambisol in ‘Meggerwald’, Switzerland." Clay Minerals 37, no. 2 (2002): 351–66. http://dx.doi.org/10.1180/0009855023720039.

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AbstractTwo soils, a haplic Podzol and a dystric Cambisol, developed from post-glacial tills, were studied with respect to their soil chemistry and clay mineralogy. Although the state factors (age, geology, topography, climate) of soil formation were almost identical, two different types developed. The E horizon of the Podzol contained more smectite, characterized by a montmorillonite-beidellitemixed phase. The neoformation of smectite could be traced back to the weathering of mica and chlorite. The Podzol had less hydroxy-interlayered smectite (HIS) in the surface horizons than the Cambisol. A larger amount of chelating compounds in the E horizon of the Podzol either transformed HIS into smectites or inhibited the formation of HIS and favoured the formation of smectites. The physical structure of the soil material is believed to be the most important factor in the different modes of soil evolution. The greater abundance of coarse pores in the topsoil at the Podzol site probably led to a faster eluviation of base cations, a different vegetation at ground level, and, consequently, to a faster soil evolution with the formation of spodic horizons.

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Pulat, Hasan Firat, Yeliz Yukselen-Aksoy, and İsfendiyar Egeli. "The effect of soil mineralogy and pore fluid chemistry on the suction and swelling behavior of soils." Bulletin of Engineering Geology and the Environment 73, no. 1 (2013): 37–42. http://dx.doi.org/10.1007/s10064-013-0499-y.

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Loveland, P. J., I. G. Wood, and A. H. Weir. "Clay mineralogy at Rothamsted: 1934—1988." Clay Minerals 34, no. 1 (1999): 165–83. http://dx.doi.org/10.1180/000985599546019.

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AbstractSoil clay mineralogy at Rothamsted began in the early 1930s, and quickly focused on technique, swelling minerals, micas and sorption phenomena. By the mid-1940s interest had extended to the formation and spatial distribution of soil clays with the move of the Soil Survey of England and Wales to Rothamsted. These themes continued for the next 40 years. Considerable contributions were made to crystal chemistry and structure determinations, and the relationship of these to the sorption and desorption of water and organic molecules, and the behaviour of soil K. The pattern of soil clay mineralogy was determined for large parts of England and Wales, and absorbed into soil mapping. The work on X-ray diffraction appeared in the Mineralogical Society Monographs on this subject. These, and the Monograph on Clay Chemistry, which reached their final form in the 1980s, are the lasting monuments to soil clay mineralogical research at Rothamsted.

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Thompson, CH. "Genesis of podzols on coastal dunes in southern Queensland .I. Field relationships and profile morphology." Soil Research 30, no. 5 (1992): 593. http://dx.doi.org/10.1071/sr9920593.

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This paper is the first of a series reporting studies in the genesis of podzols and humus podzols on coastal dunes in a chronosequence that spans >700K yrs. It is concerned mainly with temporal changes in profile morphology across a podzol chronosequence and with brief descriptions of sites chosen for genetic studies. It summarizes the geology, geomorphology and general mineralogy of dune systems at Cooloola and North Stradbroke Island and briefly discusses the effects of parent material, geomorphic component, climate, dune denudation and vegetation on soil development. Its purpose is to provide a field and morphological framework for other papers in the series dealing essentially with laboratory investigations and interpretations of the chemistry, mineralogy and genesis of these subtropical soils.

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Uehara, Goro, and Gavin Gillman. "The Mineralogy, Chemistry, and Physics of Tropical Soils with Variable Charge Clays." Soil Science 139, no. 4 (1985): 380. http://dx.doi.org/10.1097/00010694-198504000-00019.

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Mendes, Wanderson de Sousa, José A. M. Demattê, Benito Roberto Bonfatti, Maria Eduarda B. Resende, Lucas Rabelo Campos, and Antonio Carlos Saraiva da Costa. "A novel framework to estimate soil mineralogy using soil spectroscopy." Applied Geochemistry 127 (April 2021): 104909. http://dx.doi.org/10.1016/j.apgeochem.2021.104909.

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Fall, Aïdara C. A. Lamine, Jean-Pierre Montoroi, and Karl Stahr. "Coastal acid sulfate soils in the Saloum River basin, Senegal." Soil Research 52, no. 7 (2014): 671. http://dx.doi.org/10.1071/sr14033.

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Soils in boundary conditions of contrasting ecosystems generally show unique features. Transition often leads to changes in soil-forming processes, whereby the environment never comes to equilibrium and therefore the soil chemistry and mineralogy show different influences. Such an environment was analysed in the Saloum River basin, west-central Senegal. The objective was to identify the main pedogenic processes prevailing in this saline and acid pedoenvironment and to assess the influence of environmental factors (climate, topography, soil salinity and acidity) on local soil formation and mineral distribution. The terrace landscape is built up by a floodplain, a low terrace, which is still influenced by groundwater, and a middle terrace. The results show that soil properties are strongly influenced by hydrology, salinity and acidity in the entire toposequence: Gleyic Hyposalic and Hypersalic Solonchaks (Sulfatic) in the floodplain, Haplic Gleysols (Thionic) in the low terrace, and Endogleyic Arenosols in the middle terrace. The oxidation of pyrite followed by the redistribution of the main products (Fe2+ and SO42–) represents the major chemical process responsible for iron oxide and jarosite formation. Mineral distribution and crystallinity are linked to the landscape position, which controls the hydrological behaviour and reactions of Fe and S ions. Finally, we observed intrapedon processes such as gleysation, sulfidisation and sulfurisation, as well as interpedon processes such as salinisation, colluvio-alluviation and lateral eluviation. The combination of processes depends strongly on the landscape positions.

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Skarie, R. L., J. L. Richardson, G. J. McCarthy, and A. Maianu. "Evaporite Mineralogy and Groundwater Chemistry Associated with Saline Soils in Eastern North Dakota." Soil Science Society of America Journal 51, no. 5 (1987): 1372–77. http://dx.doi.org/10.2136/sssaj1987.03615995005100050050x.

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Pierzynski, G. M., T. J. Logan, S. J. Traina, and J. M. Bigham. "Phosphorus Chemistry and Mineralogy in Excessively Fertilized Soils: Descriptions of Phosphorus-rich Particles." Soil Science Society of America Journal 54, no. 6 (1990): 1583–89. http://dx.doi.org/10.2136/sssaj1990.03615995005400060012x.

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25

Mitchell, Perry J., André J. Simpson, Ronald Soong, Adi Oren, Benny Chefetz, and Myrna J. Simpson. "Solution-state NMR investigation of the sorptive fractionation of dissolved organic matter by alkaline mineral soils." Environmental Chemistry 10, no. 4 (2013): 333. http://dx.doi.org/10.1071/en13052.

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Environmental context Dissolved organic matter plays a key role in global carbon cycling and environmental contaminant transport. We use one- and two-dimensional solution-state nuclear magnetic resonance spectroscopy to characterise dissolved organic matter before and after binding to alkaline subsoils with low organic carbon content. The results show that the dissolved organic matter is selectively fractionated through preferential binding of specific organic carbon functional groups. Abstract Sorption to clay minerals is a prominent fate of dissolved organic matter (DOM) in terrestrial environments. Previous studies have observed that DOM is selectively fractionated by interactions with both pure clay minerals and acidic mineral soils. However, the specific DOM functional groups that preferentially sorb to mineral surfaces in alkaline soils require further examination because higher basicity could change the nature of these sorptive interactions. Biosolids-derived DOM was characterised using one- and two-dimensional solution-state NMR spectroscopy before and after sorption to three alkaline subsurface mineral soils with varying mineralogy. Carboxylic DOM components sorbed preferentially to all soils, likely due to cation bridging and ligand exchange mechanisms. Aliphatic constituents were selectively retained only by a soil with high clay mineral content, possibly by van der Waals interactions with montmorillonite surfaces. Polar carbohydrate and peptide components of the DOM did not exhibit preferential sorption and may remain mobile in the soil solution and potentially stimulate microbial activity. A relatively low signal from aromatic DOM components prevented a full assessment of their sorption behaviour. The results suggest that DOM is selectively fractionated by similar interactions in both acidic and alkaline soils that may play a key role in the chemical and biochemical processes of subsurface environments.

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Pierzynski, G. M., T. J. Logan, S. J. Traina, and J. M. Bigham. "Phosphorus Chemistry and Mineralogy in Excessively Fertilized Soils: Quantitative Analysis of Phosphorus-rich Particles." Soil Science Society of America Journal 54, no. 6 (1990): 1576–83. http://dx.doi.org/10.2136/sssaj1990.03615995005400060011x.

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27

Douglas, G. B., P. W. Ford, M. R. Palmer, R. M. Noble, R. J. Packett, and E. S. Krull. "Fitzroy River Basin, Queensland, Australia. IV. Identification of flood sediment sources in the Fitzroy River." Environmental Chemistry 5, no. 3 (2008): 243. http://dx.doi.org/10.1071/en07091.

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Environmental context. During flood events, the Fitzroy River is a major contributor to the loads of suspended sediment and nutrients to the southern Great Barrier Reef. The present geochemical and modelling study provides for the first time a quantitative estimate of the temporal variation in sediment sources over an entire flood hydrograph. Basaltic soils are substantially enriched in this flood event relative to their catchment abundance. Abstract. Suspended sediment collected over a complete flood hydrograph in the Fitzroy River provided an insight into the origin and transport of sediment in this system. Strong temporal trends are evident in the proportions of catchment soil types estimated using a Bayesian mixing model in the fine (<10 μm) fraction of the suspended sediment. These temporal trends were also manifested in changes in mineralogy, major and trace element and Nd–Sr and C–N isotope geochemistry. Tertiary Basaltic soils were the most abundant catchment soil type transported in the flood event studied here, constituting 39% of the <10-μm sediment fraction, but varied between an estimated 20 and 50% of the suspended solids over the course of the flood event. The techniques used here allow quantification and comparison between flow and suspended sediment sources and are widely applicable to other river systems.

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Link, Timothy E., Michael V. Ruby, Andy Davis, and Andrew D. Nicholson. "Soil Lead Mineralogy by Microprobe: An Interlaboratory Comparison." Environmental Science & Technology 28, no. 5 (1994): 985–88. http://dx.doi.org/10.1021/es00054a035.

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Simas, Felipe N. B., Carlos E. G. R. Schaefer, Elpídio I. Fernandes Filho, Adriana C. Chagas, and Pedro C. Brandão. "Chemistry, mineralogy and micropedology of highland soils on crystalline rocks of Serra da Mantiqueira, southeastern Brazil." Geoderma 125, no. 3-4 (2005): 187–201. http://dx.doi.org/10.1016/j.geoderma.2004.07.013.

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Erlandsson Lampa, Martin, Harald U. Sverdrup, Kevin H. Bishop, Salim Belyazid, Ali Ameli, and Stephan J. Köhler. "Catchment export of base cations: improved mineral dissolution kinetics influence the role of water transit time." SOIL 6, no. 1 (2020): 231–44. http://dx.doi.org/10.5194/soil-6-231-2020.

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Abstract. Soil mineral weathering is one of the major sources of base cations (BC), which play a dual role in forest ecosystems: they function as plant nutrients and buffer against the acidification of catchment runoff. On a long-term basis, soil weathering rates determine the highest sustainable forest productivity that does not cause acidification. It is believed that the hydrologic residence time plays a key role in determining the weathering rates at the landscape scale. The PROFILE weathering model has been used for almost 30 years to calculate weathering rates in the rooting zone of forest soils. However, the mineral dissolution equations in PROFILE are not adapted for the saturated zone, and employing these equations at the catchment scale results in a significant overprediction of base cation release rates to surface waters. In this study, we use a revised set of PROFILE equations which, among other features, include retardation due to silica concentrations. Relationships between the water transit time (WTT) and soil water concentrations were derived for each base cation, by simulating the soil water chemistry along a one-dimensional flow path, using the mineralogy from a glacial till soil. We show how the revised PROFILE equations are able to reproduce patterns in BC and silica concentrations as well as BC ratios (Ca2+/BC, Mg2+/BC and Na+/BC) that are observed in the soil water profiles and catchment runoff. In contrast to the original set of PROFILE equations, the revised set of equations could reproduce the fact that increasing WTT led to a decreasing Na+/BC ratio and increasing Ca2+/BC and Mg2+/BC ratios. Furthermore, the total release of base cations from a hillslope was calculated using a mixing model, where water with different WTTs was mixed according to an externally modeled WTT distribution. The revised set of equations gave a 50 % lower base cation release (0.23 eq m−2 yr−1) than the original PROFILE equations and are in better agreement with mass balance calculations of weathering rates. Thus, the results from this study demonstrate that the revised mineral dissolution equations for PROFILE are a major step forward in modeling weathering rates at the catchment scale.

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Krull, Evelyn S., Erick A. Bestland та Will P. Gates. "Soil Organic Matter Decomposition and Turnover in a Tropical Ultisol: Evidence from δ13C, δ15N and Geochemistry". Radiocarbon 44, № 1 (2002): 93–112. http://dx.doi.org/10.1017/s0033822200064705.

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Soil organic matter (SOM), leaf litter, and root material of an Ultisol from the tropical rainforest of Kakamega, Kenya, were analyzed for stable carbon (δ13C) and nitrogen (δ15N) isotopic values as well as total organic carbon (TOC) and total nitrogen (TN) contents in order to determine trends in SOM decomposition within a very well-developed soil under tropical conditions. In addition, we quantified mineralogy and chemistry of the inorganic soil fraction. Clay mineralogical variation with depth was small and the abundance of kaolin indicates intense weathering and pedoturbation under humid tropical conditions. The soil chemistry was dominated by silica, aluminium, and iron with calcium, potassium, and magnesium as minor constituents. The relative depletion of base cations compared with silica and aluminium is an indicator for intense weathering and leaching conditions over long periods of time. Depth profiles of δ13C and δ15N showed a distinct enrichment trend down profile with a large (average 13δC = 5.0 and average 15δN= 6.3) and abrupt offset within the uppermost 10–20 cm of the soil. Isotopic enrichment with depth is commonly observed in soil profiles and has been attributed to fractionation during decomposition. However, isotopic offsets within soil profiles that exceed 3 are usually interpreted as a recent change from C4 to C3 dominated vegetation. We argue that the observed isotopic depth profiles along with data from mineralogy and chemistry of the inorganic fraction from the Kakamega Forest soil are a result of intense weathering and high organic matter turnover rates under humid tropical conditions.

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32

Bish, David. "The First X-ray Powder Diffraction Measurements on Mars." Acta Crystallographica Section A Foundations and Advances 70, a1 (2014): C4. http://dx.doi.org/10.1107/s2053273314099951.

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The CheMin instrument on the Curiosity rover measures XRD and XRF data using Co radiation in transmission geometry. It has analyzed <150 μm portions of eolian soil (Rocknest) and two drill-hole powders (John Klein and Cumberland) from a mudstone [1, 2, Figure 1]. XRD data for Rocknest soil revealed plagioclase, forsteritic olivine, augite, and pigeonite. John Klein and Cumberland are similar, with much less Fe-forsterite and more magnetite than Rocknest. Data were analyzed via Rietveld methods (Topas), and profiles were modeled using beryl-quartz data measured on Mars. CheMin's broad profiles limited analysis of minor phases (<3 wt. %), although the presence of minor phases was evaluated individually for every sample by including each in the Rietveld model and evaluating their effect on the fit. We found no evidence for any perchlorate, carbonate, or sulfate mineral (apart from anhydrite, and bassanite in the mudstones). No phyllosilicate was detected in the soil, but mudstone samples contained two different phyllosilicates, likely trioctahedral smectites. The John Klein XRD pattern had a broad ~10Å peak, whereas Cumberland showed broad peaks at ~13.2Å and ~10Å. The background in all XRD patterns suggested the presence of amorphous/poorly ordered components, which were analyzed using FULLPAT, giving ~27% amorphous content in Rocknest and ~20% in the mudstones. This mineralogy is very similar to that found in soils on the flanks of Mauna Kea volcano, Hawaii. Mineralogy differences between the Rocknest material and the mudstones may be explained by alteration of Fe-forsterite to smectite + magnetite. Combining these results with compositional estimates from unit-cell parameters and bulk chemistry will allow determinations of individual phase compositions, including that of the amorphous component(s). The exact nature of the amorphous component is unclear, but other data show that it is hydrous.

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Sollins, Phillip, Marc G. Kramer, Christopher Swanston, et al. "Sequential density fractionation across soils of contrasting mineralogy: evidence for both microbial- and mineral-controlled soil organic matter stabilization." Biogeochemistry 96, no. 1-3 (2009): 209–31. http://dx.doi.org/10.1007/s10533-009-9359-z.

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34

Inyang, Hilary I., Sunyoung Bae, and Anand Puppala. "Application of Advances in Materials Chemistry and Mineralogy in Soil Stabilization." Journal of Materials in Civil Engineering 19, no. 1 (2007): 1. http://dx.doi.org/10.1061/(asce)0899-1561(2007)19:1(1).

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35

Bell, F. G., and M. G. Culshaw. "Some geohazards caused by soil mineralogy, chemistry and microfabric: a review." Geological Society, London, Engineering Geology Special Publications 15, no. 1 (1998): 427–41. http://dx.doi.org/10.1144/gsl.eng.1998.015.01.43.

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36

Dubbin, W. E., A. R. Mermut, and H. P. W. Rostad. "Clay mineralogy of parent materials derived from uppermost Cretaceous and Tertiary sedimentary rocks in southern Saskatchewan." Canadian Journal of Soil Science 73, no. 4 (1993): 447–57. http://dx.doi.org/10.4141/cjss93-046.

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Soils developed from parent materials derived from uppermost Cretaceous and Tertiary sedimentary rocks have been delineated from those which do not contain any of these younger sediments. The present study was initiated to determine the validity of this delineation. Parent materials from six locations in southwestern Saskatchewan were collected to determine their general chemical and physical properties. Clay fractions from each of these six parent materials were then subjected to detailed chemical and mineralogical analyses. The two parent materials containing the greatest amount of post-Bearpaw bedrock sediments (Jones Creek, Scotsguard) were characterized by substantially more organic carbon and less CaCO3. The presence of coal and the absence of carbonates in local bedrocks were considered to be the source of these deviations. In general, fine clays were comprised of 64–69% smectite, 14–21% illite and 10–13% kaolinite and coarse clay contained 32–39% smectite, 25–34% illite and 11–14% kaolinite. An exception was found in two fine clays which had less smectite but 3–6% vermiculite. Total iron content of the fine clays ranged from 7.16 to 8.11% expressed as Fe2O3. However, only a small fraction of this iron was extractable using the CDB technique. There were no substantial differences in surface areas or CECs of the clay fractions. Despite minor differences in the chemistry and mineralogy of these six parent materials, a separation of the soil associations does not appear to be warranted. Key words: Parent materials, uppermost Cretaceous, Tertiary, bedrock, clay mineralogy

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Campbell, A. S., and U. Schwertmann. "Evaluation of selective dissolution extractants in soil chemistry and mineralogy by differential X-ray diffraction." Clay Minerals 20, no. 4 (1985): 515–19. http://dx.doi.org/10.1180/claymin.1985.020.4.07.

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Selective dissolution analysis is widely used to separate various soil minerals (e.g. oxides and oxyhydroxides of Al and Fe, allophanes, phyllosilicates) from each other. Although a wide variety of reagents has been used for some of these determinations, few rigorous comparative studies have been attempted. Too often, reagents used to extract particular soil components are evaluated using geological or other specimens that may bear little resemblance to soil minerals formed by pedogenic processes; the investigations of Borggaard (1982) and Chao & Zhou (1983) are two recent examples of such an approach. Insufficient use has been made of difference infrared spectra (Wada & Greenland, 1970) obtained from soil samples.

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MILLER, J. J., S. PAWLUK, and G. J. BEKE. "EVAPORITE MINERALOGY, AND SOIL SOLUTION AND GROUNDWATER CHEMISTRY OF A SALINE SEEP FROM SOUTHERN ALBERTA." Canadian Journal of Soil Science 69, no. 2 (1989): 273–86. http://dx.doi.org/10.4141/cjss89-028.

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Evaporite mineralogy, soil solution and groundwater chemistry of a saline seep from southern Alberta were investigated using chemical and mineralogical techniques, and simulations with a geochemical model (SOLMNEQ), to determine the nature of the salinity. The shallow groundwater and soil solution were dominated by Na and SO4. Although simulations with the geochemical model predicted that many evaporite minerals could theoretically precipitate below the water table and in the soil, gypsum, bassanite, and calcite were the only evaporite minerals identified. Medium to coarse, silt-size, bassanite crystals and medium, sand-size, bassanite and gypsum crystals were observed in the upper (0–30 cm) and lower (> 88 cm) profile, respectively. Calcite was indentified in all horizons. This mineral sequence cannot be explained by the Hardie-Eugster model of closed-basin brine evolution. The common-ion effect involving calcite dissolution and gypsum and/or bassanite precipitation, however, was probably an important mechanism controlling the mineral sequence observed here. Evidence of slight dissolution of bassanite crystals was observed in the surface horizon, whereas evidence of strong dissolution of bassanite and gypsum crystals was observed in the lower profile and below the water table. The results of this study suggested that gypsum and bassanite may be a major source of Ca and SO4 in the groundwater and soil solution. Key words: Saline seep, groundwater chemistry, soluble salts, evaporite mineralogy

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39

Castanha, Cristina, Susan Trumbore, and Ronald Amundson. "Methods of Separating Soil Carbon Pools Affect the Chemistry and Turnover Time of Isolated Fractions." Radiocarbon 50, no. 1 (2008): 83–97. http://dx.doi.org/10.1017/s0033822200043381.

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A variety of physical and chemical techniques are used to fractionate soil organic matter, but detailed comparisons of the different approaches and tests of how separation methods influence the properties of isolated organic matter pools are lacking. In this case study based on A horizon samples of 2 California coniferous forests soils, we 1) evaluate the effects of root removal and ultrasonic dispersion on the properties of the <2 g cm-3 light fraction and 2) compare the properties of fractions obtained by sequential density separations of ultrasonically treated soil with those obtained by density followed by acid/base hydrolysis (Trumbore et al. 1996).A root-removal effort based on hand-picking visible roots reduced the radiocarbon content and increased the estimated turnover time of the light fraction by roughly 12%. Root-removal protocols that vary between investigators thus can potentially confound variability in carbon cycling for this fraction caused by environmental factors, such as climate. Ultrasonic dispersion did not have a clear effect on the light fraction C and N content or isotopic signature, but led to a decrease in the % C and C/N of the recovered heavy fractions, and losses of 12–19% of the total soil C to the sodium metatungstate density solution.Sequentially isolated density fractions clearly differed in mineralogy and organic matter chemistry, but natural-abundance 14C analyses indicated that distinct mineral phases did not correspond to unique C-turnover pools. Density fractions containing kaolinite group minerals alone and in combination with hydroxy-interlayered vermiculite were found to harbor both fast and slow cycling carbon. In contrast, severe chemical treatment isolated a carbon pool with the lowest overall 14C content and longest inferred mean turnover time. Overall, our results show that care must be taken when relying on physical (density) separation to isolate soil fractions with different dynamics, as the details of treatment will influence the results.

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40

Egashira, Kazuhiko, Megumi Hagimine, and Abu Zofar Md Moslehuddin. "Quantity-intensity relationship for characterizing ammonium chemistry of Bangladesh soils in reference to clay mineralogy." Soil Science and Plant Nutrition 44, no. 3 (1998): 377–84. http://dx.doi.org/10.1080/00380768.1998.10414459.

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41

SPIERS, G. A., M. J. DUDAS, and L. W. TURCHENEK. "THE CHEMICAL AND MINERALOGICAL COMPOSITION OF SOIL PARENT MATERIALS IN NORTHEAST ALBERTA." Canadian Journal of Soil Science 69, no. 4 (1989): 721–37. http://dx.doi.org/10.4141/cjss89-074.

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Seven major parent materials from the Athabasca oil sands area were investigated for detailed mineralogy and chemistry. The clay mineral species identified and quantified were mica, smectite, kaolinite, chlorite and vermiculite. The fine (50–250 μm) sand mineralogical suite was dominated by quartz, with lesser amounts of Na-, K-, and Ca-feldspars, and minor amounts of individual heavy mineral species. Electronoptical examination indicated that the feldspar grains in the parent materials have undergone extensive preglacial weathering. Regional mean levels of all analyzed elements (Al, Ca, Fe, K, Mg, Na, Mn, P, Cr, Co, Cu, Ni, Pb, Sr, V, and Zn), with the exception of Ca, are related to textural variability. The variability of Ca levels within the study area is related to the occurrence of calcareous parent materials. The highest levels of all major, minor, and trace elements were associated with either the Legend unit derived largely from Cretaceous bedrock or with the modern sediments of the Athabasca delta. Key words: Soil parent materials, clay mineralogy, trace element levels, sand mineralogy, feldspar morphology

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42

Jongmans, A. G., F. van Oort, P. Buurman, A. M. Jaunet, and J. D. J. van Doesburg. "Morphology, Chemistry, and Mineralogy of Isotropic Aluminosilicate Coatings in a Guadeloupe Andisol." Soil Science Society of America Journal 58, no. 2 (1994): 501–7. http://dx.doi.org/10.2136/sssaj1994.03615995005800020036x.

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43

Sjöström, Jan, and Zhixun Lin. "Texture, chemistry, and mineralogy of acid soil profiles in Hailand, SW Sweden." GFF 118, no. 4 (1996): 227–36. http://dx.doi.org/10.1080/11035899609546258.

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44

Journet, E., Y. Balkanski, and S. P. Harrison. "A new data set of soil mineralogy for dust-cycle modeling." Atmospheric Chemistry and Physics Discussions 13, no. 9 (2013): 23943–93. http://dx.doi.org/10.5194/acpd-13-23943-2013.

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Abstract. The mineralogy of airborne dust affects the impact of dust particles on direct and indirect radiative forcing, on atmospheric chemistry and on biogeochemical cycling. It is determined partly by the mineralogy of the dust-source regions and partly by size-dependent fractionation during erosion and transport. Here we present a data set that characterizes the clay and silt sized fractions of global soil units in terms of the abundance of 12 minerals that are important for dust-climate interactions: quartz, feldspars, illite, smectite, kaolinite, chlorite, vermiculite, mica, calcite, gypsum, hematite and goethite. The basic mineralogical information is derived from the literature, and is then expanded following explicit rules, in order to characterize as many soil units as possible. We present three alternative realisations of the mineralogical maps that account for the uncertainties in the mineralogical data. We examine the implications of the new database for calculations of the single scattering albedo of airborne dust and thus for dust radiative forcing.

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45

Journet, E., Y. Balkanski, and S. P. Harrison. "A new data set of soil mineralogy for dust-cycle modeling." Atmospheric Chemistry and Physics 14, no. 8 (2014): 3801–16. http://dx.doi.org/10.5194/acp-14-3801-2014.

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Abstract. The mineralogy of airborne dust affects the impact of dust particles on direct and indirect radiative forcing, on atmospheric chemistry and on biogeochemical cycling. It is determined partly by the mineralogy of the dust-source regions and partly by size-dependent fractionation during erosion and transport. Here we present a data set that characterizes the clay and silt-sized fractions of global soil units in terms of the abundance of 12 minerals that are important for dust–climate interactions: quartz, feldspars, illite, smectite, kaolinite, chlorite, vermiculite, mica, calcite, gypsum, hematite and goethite. The basic mineralogical information is derived from the literature, and is then expanded following explicit rules, in order to characterize as many soil units as possible. We present three alternative realizations of the mineralogical maps, taking the uncertainties in the mineralogical data into account. We examine the implications of the new database for calculations of the single scattering albedo of airborne dust and thus for dust radiative forcing.

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46

Eberl, D. D., and David B. Smith. "Mineralogy of soils from two continental-scale transects across the United States and Canada and its relation to soil geochemistry and climate." Applied Geochemistry 24, no. 8 (2009): 1394–404. http://dx.doi.org/10.1016/j.apgeochem.2009.04.010.

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47

Burkins, Derek L., Joel D. Blum, Kevin Brown, Robert C. Reynolds, and Yigal Erel. "Chemistry and mineralogy of a granitic, glacial soil chronosequence, Sierra Nevada Mountains, California." Chemical Geology 162, no. 1 (1999): 1–14. http://dx.doi.org/10.1016/s0009-2541(99)00074-1.

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48

Tsao, Tsung Ming, Yue Ming Chen, Hwo Shuenn Sheu, et al. "Red soil chemistry and mineralogy reflect uniform weathering environments in fluvial sediments, Taiwan." Journal of Soils and Sediments 12, no. 7 (2012): 1054–65. http://dx.doi.org/10.1007/s11368-012-0495-z.

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Malomo, S. "Mineralogy and chemistry of different fractions of some soil laterites from northeast Brazil." Chemical Geology 60, no. 1-4 (1987): 101–9. http://dx.doi.org/10.1016/0009-2541(87)90115-x.

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50

Yesavage, Tiffany, Gary E. Stinchcomb, Matthew S. Fantle, Peter B. Sak, Alexander Kasznel, and Susan L. Brantley. "Investigation of a diabase-derived regolith profile from Pennsylvania: Mineralogy, chemistry and Fe isotope fractionation." Geoderma 273 (July 2016): 83–97. http://dx.doi.org/10.1016/j.geoderma.2016.03.004.

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Journal articles on the topic 'Soils Soil chemistry. Soil mineralogy'

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