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R Protz - One of the best experts on this subject based on the ideXlab platform.

  • the representative elementary area rea in studies of quantitative Soil Micromorphology
    Geoderma, 1999
    Co-Authors: A J Vandenbygaart, R Protz
    Abstract:

    Abstract A fundamental question to be answered for studies in quantitative Micromorphology at varying scales is: What is the minimum area on a Soil thin section or block that is required to represent the pedofeature of interest based on its distribution in Soil space? This paper investigates the necessity of establishing a representative elementary area (REA) in the study of pedofeatures for quantitative analysis of pedofeatures. It also proposes a means by which an absolute REA may be determined. This was achieved by suggesting that the REA for voids on 3.5×4.7 cm Soil thin sections is attained at the area where the measurements made on a parameter in three successive areas of measurements do not change ±10% relative to the next greater area of measurement. Using this method, the REA for void pedofeatures in the size range of 50 to 2000 μm on 3.5×4.7 cm thin sections from silt loam agricultural Soils of southern Ontario was investigated. The REA was achieved for total void area between 50 and 500 μm in diameter in 99% (97 of 98) of the thin sections, whereas for total perimeter 97% (95 of 98) of the sections achieved the REA. The average REA between 50 and 500 μm in diameter for total void area and perimeter was 5.09 and 5.00 cm 2 , respectively. The average REA between 500 and 2000 μm for total void area and perimeter was 6.73 and 4.95 cm 2 , respectively. It is suggested that the REA determination should be performed in every quantitative Soil micromorphological study in order that the parameter of interest is an adequate representation of that feature in Soil space.

  • changes in pore structure in a no till chronosequence of silt loam Soils southern ontario
    Canadian Journal of Soil Science, 1999
    Co-Authors: A J Vandenbygaart, R Protz, A D Tomlin
    Abstract:

    Many research studies have dealt with the influences of minimum or no-till Soil management practices on the major physical, chemical, biological and morphological properties in the Soil profile. However little work has been done on the assessment of the rates of changes in pore properties as management practices are converted from conventional to no-till (NT) methods. Short-term changes in Soil Micromorphology attributed to conversion to no-till from conventionally tilled management are evaluated in this paper. As the number of years in no-till increased there was a decrease in the number pores of 30- to 100-µm diameter in the no-till Soils. However, pores from 100- to 500-µm diameter increased in number only after 4 yr of NT. The pores of this size are important for water storage, transmission and root development. The decline in the number of these pores after no-till initiation followed by the increase after 4 yr may explain why crop yields tend to be lower only after the first few years after implemen...

  • towards systematic image analysis in the study of Soil Micromorphology
    Sciences of Soils, 1998
    Co-Authors: R Protz, A J Vandenbygaart
    Abstract:

    Operational laboratories for quantitative image analysis of Soil thin sections are now possible. This paper describes the evolving methodology at the University of Guelph, Ontario, Canada, and its application in selected Canadian Soils. The paper deals with the collection of data under transmitted, reflected and circularly polarized illumination. The perfect registration of all data is achieved simply by not moving the thin section. The protocol for analysis of differentiation of voids, organic matrix, clay coatings, carbonate and iron concretions is presented. The storage and retrieval of data from CD-ROMs for analysis and sharing is also outlined. Once the digital imagery is stored it is easily useable for more studies as a greater understanding of the value of data is recognized. The paper makes the case for much greater use of the Soil thin sections that already exist in the laboratories around the world.

  • an application of spectral image analysis to Soil Micromorphology 1 methods of analysis
    Geoderma, 1992
    Co-Authors: R Protz, Stewart J Sweeney, Catherine A Fox
    Abstract:

    Abstract Digital images of polished Soil sections were produced using an Eikonix Scanner (4096 detectors in a linear array). Separate images were collected in each of the red, green and blue wavelengths of visible (incandescent source) light and in the blue wavelength for ultraviolet (UV) illumination. These spectral data sets were registered, displayed and analyzed as colour composite images with an EASI/PACE spectral image analysis system. Visual identification and delineation of pedological features were based on their morphologies and colours. This task was aided by the image enhancement capabilities of the system. Features classified included skeletal grains, void space, mottles, organic material, manganese concretions, carbonates and depletion zones. An interpretive colour code for image display of these classified Soil features was proposed and implemented. The percentages of the total image area occupied by each of these pedological features were derived from the final image classification.

  • an application of spectral image analysis to Soil Micromorphology 2 comparison of two Soil profiles
    Geoderma, 1992
    Co-Authors: Stewart J Sweeney, R Protz, Catherine A Fox
    Abstract:

    Abstract Pedological features in undisturbed samples from similar depths in two Brookston clay loam Soil (Orthic Humic Gleysol or Typic Haplaquoll) profiles were compared: one in the never-cultivated state (NC) and the other under long-term (30 years), continuous-corn (Zea mays L.) (CC). Colour digital images of polished section samples from the NC Ah2, Bg and Ckg and the CC Ap, Bkg and Ckg horizons were produced with an Eikonix scanner and analyzed with an EASI/PACE spectral image analysis system. The spectral intensity values of delineated features were grouped into classes to produce maps of their spatial distribution. Image areal percentages for the features were measured. Void space feature results were compared with previous point-counting and single-channel image analyses. Quantitative and visual results for features indicated that the Soil compaction associated with the CC cropping practice gave the Ap horizon properties that more closely resembled those of the deeper B and C horizons than those of the NC Ah2 horizon. These properties included: (1) a reduced macroporosity ( 50%); (2) organic material dispersed throughout the peds (light-coloured) and concentrated only along the macropores (dark-coloured); and (3) weakly developed gleysolic characteristics (faint mottles) in the interior regions of the peds (27% of sample area).

Catherine A Fox - One of the best experts on this subject based on the ideXlab platform.

  • an application of spectral image analysis to Soil Micromorphology 1 methods of analysis
    Geoderma, 1992
    Co-Authors: R Protz, Stewart J Sweeney, Catherine A Fox
    Abstract:

    Abstract Digital images of polished Soil sections were produced using an Eikonix Scanner (4096 detectors in a linear array). Separate images were collected in each of the red, green and blue wavelengths of visible (incandescent source) light and in the blue wavelength for ultraviolet (UV) illumination. These spectral data sets were registered, displayed and analyzed as colour composite images with an EASI/PACE spectral image analysis system. Visual identification and delineation of pedological features were based on their morphologies and colours. This task was aided by the image enhancement capabilities of the system. Features classified included skeletal grains, void space, mottles, organic material, manganese concretions, carbonates and depletion zones. An interpretive colour code for image display of these classified Soil features was proposed and implemented. The percentages of the total image area occupied by each of these pedological features were derived from the final image classification.

  • an application of spectral image analysis to Soil Micromorphology 2 comparison of two Soil profiles
    Geoderma, 1992
    Co-Authors: Stewart J Sweeney, R Protz, Catherine A Fox
    Abstract:

    Abstract Pedological features in undisturbed samples from similar depths in two Brookston clay loam Soil (Orthic Humic Gleysol or Typic Haplaquoll) profiles were compared: one in the never-cultivated state (NC) and the other under long-term (30 years), continuous-corn (Zea mays L.) (CC). Colour digital images of polished section samples from the NC Ah2, Bg and Ckg and the CC Ap, Bkg and Ckg horizons were produced with an Eikonix scanner and analyzed with an EASI/PACE spectral image analysis system. The spectral intensity values of delineated features were grouped into classes to produce maps of their spatial distribution. Image areal percentages for the features were measured. Void space feature results were compared with previous point-counting and single-channel image analyses. Quantitative and visual results for features indicated that the Soil compaction associated with the CC cropping practice gave the Ap horizon properties that more closely resembled those of the deeper B and C horizons than those of the NC Ah2 horizon. These properties included: (1) a reduced macroporosity ( 50%); (2) organic material dispersed throughout the peds (light-coloured) and concentrated only along the macropores (dark-coloured); and (3) weakly developed gleysolic characteristics (faint mottles) in the interior regions of the peds (27% of sample area).

Paul Goldberg - One of the best experts on this subject based on the ideXlab platform.

  • optical dating and Soil Micromorphology at maccauley s beach new south wales australia
    Earth Surface Processes and Landforms, 2015
    Co-Authors: Nathan R Jankowski, Paul Goldberg, Zenobia Jacobs
    Abstract:

    The ability to position landscapes in a context of time and space is a particular goal of Quaternary science research. The lack of context for dating samples published previously for MacCauley's Beach, an important site for the reconstruction of Australian sea levels, warranted a re-evaluation of both the site stratigraphy and chronology. In this study, we combined optically stimulated luminescence (OSL) dating of sedimentary quartz grains and Soil Micromorphology of the same samples to improve our understanding of the depositional history and chronology of the sediments. This combination allowed the contextualization of samples not only in time and space, but also in terms of their depositional histories. The latter is important in OSL dating, where pre-, syn- and post-depositional processes can all influence the accuracy and precision of the final age estimates. The sediment profile at MacCauley's Beach is made up of three major units. The basal mottled mud layer has undergone extensive pedogenesis since deposition, and only a minimum age of 14.7 ± 2.7 ka could be calculated. The overlying grey mud, with OSL ages from the bottom and top of the unit of 10.0 ± 0.7 and 7.7 ± 0.5 ka, respectively, shows evidence of Soil structure collapse. This unit correspond to the onset of the mid-Holocene sea-level high stand for this region. The overlying sand layer was first deposited at 7.5 ± 0.4 ka, with deposition continuing beyond 6.6 ± 0.4 ka. Not only does the chronology presented constrain the timing of deposition (and the extent of post-depositional processes) at MacCauley's Beach, but the methodological approach used here can be applied to any site to aid in the interpretation of formation processes and assess their influence on OSL age determination. Copyright © 2014 John Wiley & Sons, Ltd.

  • deciphering site formation processes through Soil Micromorphology at contrebandiers cave morocco
    Journal of Human Evolution, 2014
    Co-Authors: Vera Aldeias, Paul Goldberg, Harold L Dibble, Mohamed Elhajraoui
    Abstract:

    Abstract Contrebandiers Cave preserves a Late Pleistocene sequence containing Middle Stone Age (MSA) so-called Maghrebian Mousterian and Aterian occupations, spanning from ∼126 to 95 ka (thousands of years ago), followed by spatially restricted Iberomaurusian industries. Micromorphological analyses, complemented by instrumental mineralogical identification and fabric orientation, allowed for the reconstruction of the main site formation processes at the site. Initial deposition is characterized by local reworking of marine shelly sands dating to Marine Isotopic Stage 5e (MIS5e). The subsequent stratification reveals sedimentary dynamics predominantly associated with gravity-driven inputs and contributions from weathering of the encasing bedrock, at the same time that anthropogenic sediments were being accumulated. The allochthonous components reflect Soil degradation and vegetation changes around the cave during the last interglacial. Human occupations seems to be somewhat ephemeral in nature, with some stratigraphic units apparently lacking archaeological components, while in others the human-associated deposits (e.g., burned bones, charcoal, and ashes) can be substantial. Ephemeral breaks in sedimentation and/or erosion followed by stabilization are mainly discernible microscopically by the presence of phosphatic-rich laminae interpreted as short-lived surfaces, peaks of increased humidity and colonization by plants. More substantial erosion affects the uppermost Aterian layers, presumably due to localized reconfigurations of the cave's roof. The subsequent Iberomaurusian deposits are not in their primary position and are associated with well-sorted silts of aeolian origin. While the effects of chemical diagenesis are limited throughout the whole stratigraphic sequence, physical bioturbation (e.g., by wasps, rodents, and earthworms) is more pervasive and leads to localized movement of the original sedimentary particles.

  • Soil Micromorphology of gibraltar caves coprolites
    2012
    Co-Authors: Richard I Macphail, Paul Goldberg
    Abstract:

    extract] Introduction Several coprolites (fossil faeces) were collected from the Middle Palaeolithic levels in Gorham's and Vanguard Caves during the 1995-1998 excavations (Finlayson and Finlayson 2000; Stringer et al. 2000). Disciplines Medicine and Health Sciences | Social and Behavioral Sciences Publication Details Macphail, R. I. & Goldberg, P. (2012). Soil Micromorphology of Gibraltar Caves coprolites. In R. N. E. Barton, C. B. Stringer & J. C. Finlayson (Eds.), Neanderthals in Context: a report of the 1995-1998 excavations at Gorham's and Vanguard Caves, Gibraltar (pp. 240-242). Oxford, United Kingdom: Oxford University School of Archaeology. © Copyright 2012. Oxford University School of Archaeology and Individual authors reproduced with permission. This book chapter is available at Research Online: http://ro.uow.edu.au/smhpapers/3084

  • vanguard cave sediments and Soil Micromorphology
    2012
    Co-Authors: Richard I Macphail, Paul Goldberg, R N E Barton
    Abstract:

    extract] Introduction Vanguard Cave contains a sequence of over 17 m of deposits, generally made up of massive, coarse to medium sands interfingered with tabular to lenticular units of silts and silty sands (Fig 13.1). Disciplines Medicine and Health Sciences | Social and Behavioral Sciences Publication Details Macphail, R. I., Goldberg, P. & Barton, R. N. E. (2012). Vanguard Cave sediments and Soil Micromorphology. In R. N. E. Barton, C. B. Stringer & J. C. Finlayson (Eds.), Neanderthals in Context: a report of the 1995-1998 excavations at Gorham's and Vanguard Caves, Gibraltar (pp. 193-210). Oxford, United Kingdom: Oxford University School of Archaeology. © Copyright 2012. Oxford University School of Archaeology and Individual authors reproduced with permission. This book chapter is available at Research Online: http://ro.uow.edu.au/smhpapers/3083

  • Micromorphology and context
    Quaternary International, 2010
    Co-Authors: Paul Goldberg, Francesco Berna
    Abstract:

    Abstract Context is an important concept in archaeology, although the term tends to have a variety of meanings to different people. In this brief note we illustrate how context can be considered at a microstratigraphic scale using the technique of Soil Micromorphology. Examples are given from the sites of Geisenklosterle (Germany), Sibudu (South Africa), and Pech de l'Aze IV (France) to show that Micromorphology is an indispensible and robust tool for not only documenting the contextual position of archaeological objects and features within the matrix of the site but also for making accurate interpretations of the archaeological record.

Stewart J Sweeney - One of the best experts on this subject based on the ideXlab platform.

  • an application of spectral image analysis to Soil Micromorphology 1 methods of analysis
    Geoderma, 1992
    Co-Authors: R Protz, Stewart J Sweeney, Catherine A Fox
    Abstract:

    Abstract Digital images of polished Soil sections were produced using an Eikonix Scanner (4096 detectors in a linear array). Separate images were collected in each of the red, green and blue wavelengths of visible (incandescent source) light and in the blue wavelength for ultraviolet (UV) illumination. These spectral data sets were registered, displayed and analyzed as colour composite images with an EASI/PACE spectral image analysis system. Visual identification and delineation of pedological features were based on their morphologies and colours. This task was aided by the image enhancement capabilities of the system. Features classified included skeletal grains, void space, mottles, organic material, manganese concretions, carbonates and depletion zones. An interpretive colour code for image display of these classified Soil features was proposed and implemented. The percentages of the total image area occupied by each of these pedological features were derived from the final image classification.

  • an application of spectral image analysis to Soil Micromorphology 2 comparison of two Soil profiles
    Geoderma, 1992
    Co-Authors: Stewart J Sweeney, R Protz, Catherine A Fox
    Abstract:

    Abstract Pedological features in undisturbed samples from similar depths in two Brookston clay loam Soil (Orthic Humic Gleysol or Typic Haplaquoll) profiles were compared: one in the never-cultivated state (NC) and the other under long-term (30 years), continuous-corn (Zea mays L.) (CC). Colour digital images of polished section samples from the NC Ah2, Bg and Ckg and the CC Ap, Bkg and Ckg horizons were produced with an Eikonix scanner and analyzed with an EASI/PACE spectral image analysis system. The spectral intensity values of delineated features were grouped into classes to produce maps of their spatial distribution. Image areal percentages for the features were measured. Void space feature results were compared with previous point-counting and single-channel image analyses. Quantitative and visual results for features indicated that the Soil compaction associated with the CC cropping practice gave the Ap horizon properties that more closely resembled those of the deeper B and C horizons than those of the NC Ah2 horizon. These properties included: (1) a reduced macroporosity ( 50%); (2) organic material dispersed throughout the peds (light-coloured) and concentrated only along the macropores (dark-coloured); and (3) weakly developed gleysolic characteristics (faint mottles) in the interior regions of the peds (27% of sample area).

Richard I Macphail - One of the best experts on this subject based on the ideXlab platform.