Kooperativer Bibliotheksverbund

Berlin Brandenburg

and
and

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Ritz, Karl  (10)
Type of Medium
Language
Year
  • 1
    Language: English
    In: 2009
    Keywords: Geochemistry ; Geokemi ; Soil Science ; Markvetenskap
    Source: SwePub (National Library of Sweden)
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Language: English
    In: Spanish Journal of Agricultural Research, 01 April 2010, Vol.8, pp.S86-S95
    Description: The mycorrhizal colonisation of plants grown in unmanaged soils from two restoration sites with a fire history in Northern Portugal was evaluated from the perspective of supporting restoration programmes. To promote restoration of original tree stands, Quercus ilex L. and Pinus pinaster...
    Keywords: Environmental Sciences ; Agriculture ; Environmental Sciences
    ISSN: 1695-971X
    E-ISSN: 2171-9292
    Source: Hyper Article en Ligne (CCSd)
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Language: English
    In: Geoderma, 2006, Vol.133(3), pp.398-407
    Description: We investigated the utility of combining micro-scale computed tomography (micro-CT), image analysis and geostatistics to quantify pore geometry at spatial scales ranging from 4.4 μm to 2 mm. To facilitate this, we investigated soil taken from an old permanent upland pasture known to support very high levels of microbial diversity and that had not been cultivated for many centuries. Aggregates (〈 3 mm in diameter) from three treatments (control, sewage sludge amended and biocide treated) derived from the site were imaged using synchrotron-based computed microtomography. Image analysis was used to determine aggregate porosity and pore shape parameters, and semivariance analysis was used to measure the spatial correlation of pore space within the three land treatments. For all plots high porosities were observed (c. 30%) at scales below 3 mm. High variations of porosity were also observed, ranging from 22% to 47%, but no significant differences among treatments were found. No significant differences among treatments were found in the distribution of pores within aggregates, as revealed by semivariance analysis, or in pore shape parameters. No treatment effects were observed. However, the work presented here shows that the combination of approaches adopted has great potential for quantifying the soil microbial physical habitat. Future work, should investigate the use of these novel techniques in more controlled soil ecosystems to provide an exciting new way of understanding the soil-microbe interactions at appropriate scales.
    Keywords: X-Ray Computer Tomography ; Aggregates ; Microscale ; Agriculture
    ISSN: 0016-7061
    E-ISSN: 1872-6259
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Language: English
    In: Soil Biology and Biochemistry, 2007, Vol.39(8), pp.1835-1850
    Description: Soils are structurally heterogeneous across a wide range of spatio-temporal scales. Consequently, external environmental conditions do not have a uniform effect throughout the soil, resulting in a large diversity of micro-habitats. It has been suggested that soil function can be studied without explicit consideration of such fine detail, but recent research has indicated that the micro-scale distribution of organisms may be of importance for a mechanistic understanding of many soil functions. Current techniques still lack the adequate sensitivity and resolution for data collection at the micro-scale, and the question ‘How important are various soil processes acting at different scales for ecological function?’ is therefore challenging to answer. The nano-scale secondary ion mass spectrometer (NanoSIMS) represents the latest generation of ion microprobes, which link high-resolution microscopy with isotopic analysis. The main advantage of NanoSIMS over other secondary ion mass spectrometers is its ability to operate at high mass resolution, whilst maintaining both excellent signal transmission and spatial resolution (down to 50 nm). NanoSIMS has been used previously in studies focussing on presolar materials from meteorites, in material science, biology, geology and mineralogy. Recently, the potential of NanoSIMS as a new tool in the study of biophysical interfaces in soils has been demonstrated. This paper describes the principles of NanoSIMS and discusses the potential of this tool to contribute to the field of biogeochemistry and soil ecology. Practical considerations (sample size and preparation, simultaneous collection of isotopes, mass resolution, isobaric interference and quantification of the isotopes of interest) are discussed. Adequate sample preparation, avoiding bias due to artefacts, and identification of regions-of-interest will be critical concerns if NanoSIMS is used as a new tool in biogeochemistry and soil ecology. Finally, we review the areas of research most likely to benefit from the high spatial and high mass resolution attainable with this new approach.
    Keywords: Nanosims ; Mass Spectrometry ; Stable Isotopes ; Soil Heterogeneity ; Microbial Communities ; Agriculture ; Chemistry
    ISSN: 0038-0717
    E-ISSN: 1879-3428
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Language: English
    In: Soil Science Society of America Journal, March-April, 2004, Vol.68(2), p.346(6)
    Description: The characterization of the soil habitat is of fundamental importance to an understanding of processes associated with sustainable management such as environmental flows, bioavaiiability, and soil ecology. We describe a method for quantifying and explicitly modeling the heterogeneity of soil using a stochastic approach. The overall aim is to develop a model capable of simultaneously reproducing the spatial statistical properties of both the physical and biological components of soil architecture. A Markov chain Monte Carlo (MCMC) methodology is developed that uses a novel neighborhood and scanning scheme to model the two-dimensional spatial structure of soil, based on direct measurements made from soil thin sections. The model is considerably more efficient and faster to implement than previous approaches, and allows accurate modeling of larger structures than has previously been possible. This increased efficiency 'also makes it feasible to extend the approach to three dimensions and to simultaneously study the spatial distribution of a greater number of soil components. Examples of two-dimensional structures created by the models are presented and their statistical properties are shown not to differ significantly from those of the original visualizations.
    Keywords: Soil Structure -- Models
    ISSN: 0361-5995
    E-ISSN: 14350661
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Language: English
    In: Microbial Ecology, 2006, Vol.52(1), pp.151-158
    Description: Soils contain the greatest reservoir of biodiversity on Earth, and the functionality of the soil ecosystem sustains the rest of the terrestrial biosphere. This functionality results from complex interactions between biological and physical processes that are strongly modulated by the soil physical structure. Using a novel combination of biochemical and biophysical indicators and synchrotron microtomography, we have discovered that soil microbes and plant roots microengineer their habitats by changing the porosity and clustering properties (i.e., spatial correlation) of the soil pores. Our results indicate that biota act to significantly alter their habitat toward a more porous, ordered, and aggregated structure that has important consequences for functional properties, including transport processes. These observations support the hypothesis that the soil–plant–microbe complex is self-organized.
    Keywords: Ecosystems;
    ISSN: 0095-3628
    E-ISSN: 1432-184X
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Language: English
    In: FEMS Microbiology Ecology, 2003, Vol.44(2), pp.203-215
    Description: Biological soil thin-sections and a combination of image analysis and geostatistical tools were used to conduct a detailed investigation into the distribution of bacteria in soil and their relationship with pores. The presence of spatial patterns in the distribution of bacteria was demonstrated at the microscale, with ranges of spatial autocorrelation of 1 mm and below. Bacterial density gradients were found within bacterial patches in topsoil samples and also in one subsoil sample. Bacterial density patches displayed a mosaic of high and low values in the remaining subsoil samples. Anisotropy was detected in the spatial structure of pores, but was not detected in relation to the distribution of bacteria. No marked trend as a function of distance to the nearest pore was observed in bacterial density values in the topsoil, but in the subsoil bacterial density was greatest close to pores and decreased thereafter. Bacterial aggregation was greatest in the cropped topsoil, though no consistent trends were found in the degree of bacterial aggregation as a function of distance to the nearest pore. The implications of the results presented for modelling and predicting bacterial activity in soil are discussed. ; p. 203-215.
    Keywords: Spatial Patterns ; Geostatistics ; Soil Bacteria ; Soil Thin Sections ; Soil Structure ; Image Analysis ; Environmental Sciences ; Biology
    ISSN: 0168-6496
    E-ISSN: 1574-6941
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Language: English
    In: FEMS Microbiology Ecology, 2001, Vol.37(1), pp.67-77
    Description: A method for determining the number and in situ spatial distribution of bacterial cells over spatial scales ranging from micrometres to centimetres in mineral soils is described. Biological thin sections of undisturbed cores of soil were prepared in order to preserve the spatial distribution of bacterial cells. Composite (tessellated) images in which individual bacteria can be resolved within an area of 0.282 mm2 were acquired by means of a motorised scanning microscope stage. An image processing and analysis procedure was developed to determine the numbers and locations of bacterial cells in the composite images. The image processing procedure first homogenised the background of the images and then discriminated between bacteria and non-bacterial features using the colour and morphological properties of the images of the bacterial cells. Feature edges were detected in the green channel of colour (red, green, blue) images and bacterial cell edges were confirmed in the blue channel after elimination of autofluorescent features in the red channel. No significant difference was found between the number of bacteria or associated distributions determined automatically and control values derived interactively on individual fields of view. Data relating to total bacterial counts in thin sections and in paired dispersed samples suggested that all soil bacteria were being visualised in thin sections. Significant differences between samples taken from a depth profile of a fallow arable soil were found for both cell numbers and for cell distribution as measured by an index of dispersion. ; p. 67-77.
    Keywords: Soil Biological Thin Section ; Bacterial Spatial Distribution ; Soil Structure ; Biological Dispersion ; Environmental Sciences ; Biology
    ISSN: 0168-6496
    E-ISSN: 1574-6941
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Language: English
    In: The spatial distribution of microbes in the environment
    Description: There is a growing body of evidence that the spatial distribution of bacteria and their relationships with other soil features play a significant role in the macroscopic function of soil. In the past this has not been widely appreciated, possibly due to the difficulty of studying soils...
    Keywords: Life Sciences ; Ecology, Environment
    Source: Hyper Article en Ligne (CCSd)
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Language: English
    In: The Spatial Distribution of Microbes in the Environment, pp.61-85
    Description: There is a growing body of evidence that the spatial distribution of bacteria and their relationships with other soil features play a significant role in the macroscopic function of soil. In the past this has not been widely appreciated, possibly due to the difficulty of studying soils at scales that are relevant to bacterial communities. This paper reviews the evidence for the influence of microscale interactions on function at larger scales and describes recent methodological advances that allow the microscale spatial distribution of bacterial cells and bacterial activities to be quantified. Approaches for integrating the microscale into models of soil function are briefly discussed as are new techniques that have the potential to improve our understanding of microbial – habitat interactions and of how these are linked to soil function. Keywords: bacterial spatial distribution, microscale, microhabitat, scale, biological thin sections, microsampling
    Keywords: Life Sciences ; Microbial Ecology ; Statistics for Engineering, Physics, Computer Science, Chemistry & Geosciences ; Biogeosciences ; Biology
    ISBN: 9781402062155
    ISBN: 140206215X
    Source: SpringerLink Books
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages