The soil section provides a range of analytical services dedicated to the analysis of soils, peats, sediments and related materials. Dedicated staff and equipment provide high quality, accredited (ISO 17025), analytical data. Supporting both the research scientists across multiple disciplines and the requirements of industrial clients across a range of sectors.
Principal contacts for Soil and Plant Analysis:
Two Instron universal test frames for mechanical testing and a Haake Rheometer including a Peltier unit
Instron 5966 and Instron 5544 Universal Testing Systems
Within the group we have two universal test frames for the mechanical testing of materials. Both machines have the capability to test specimens in both tension and compression recording stress and strain at high resolution. Applications for such equipment include the biomechanical testing of plant material (root and stem tissue), penetrometer measurement of soil cores, compression testing of soils and tear testing of composite materials.
Instron 5966 – Dual Column
- 10 kN capacity
- 1256 mm vertical test space
- Load measurement accuracy: +/- 0.5% of reading down to 1/500 of load cell
- Up to 1 kHz data acquisition rate simultaneous on load and extension channels
- Speed range of 0.001 – 3000 mm/min
- Thousands of optional grips and fixtures
- Full CE compliance
Instron 5544 – Single Column
- 2 kN capacity
- 1076 mm vertical test space
- Load measurement accuracy: +/- 1.0% of reading down to 1/250 of load cell capacity
- Up to 1 kHz data acquisition rate simultaneous on load and extension channels
- Speed range of 0.05 – 1000 mm/min
- Thousands of optional grips and fixtures
- Full CE compliance
Further information on this equipment can be found at www.instron.co.uk or contact Kenneth Loades.
Thermo Scientific Haake Mars Rheometer
One of our group resources is a rheometer used for measuring the properties, such as viscosity, of pastes, liquids and slurries when subjected to shear forces from rotating plates. Due to the effects of temperature on sample properties we also have a Peltier controlled cone and plate unit.
- Torque range of 0.05 ?NM – 200mNm
- Torque resolution of 0.5 nNm
- Oscillation frequency of 10-5 – 100 Hz
- Normal force capacity of 0.01 – 50 N at a resolution of 0.001 N
- Peltier controlled cone and plate system allowing temperature control of -60oC – 185oC
Soil section
Soil physical testing
The laboratory operates two instruments for determining particle size distribution in soils; a Mastersizer 2000 and Mastersizer 3000 (Malvern Instruments).
The instruments use laser diffraction to resolve particles from the sub-micron range up to approximately 2000 µm, typically after dispersion within an aqueous matrix. Output from the instrument can be customised to suit client requirements, e.g. describing specific output parameters – clay, silt and sand.
Traditional analytical services determining particle size by hydrometer and/or sieving are undertaken by the laboratory, complimenting particle size determination using laser diffraction.
Total C and N
A Thermo FlashEA 1112 Elemental Analyser is available for the analysis of samples to determine total carbon and nitrogen concentrations, within soils, vegetation and related materials. Where organic carbon concentrations are required within soil with inorganic C sources, e.g. carbonate material, techniques are available for removing the carbonate prior to analysis.
Elemental analysis
The elemental concentrations of a variety of matrices, e.g. soils, plants are obtained following digestion in a range of strong mineral acids, typically nitric, or aqua regia (nitric and hydrochloric) acids. Samples are digested using a Digiprep Digestion system, or Gerhardt digestion system, both of which have programmable functionality to ensure efficient and accurate digestion.
The elemental concentrations of the digestion solutions obtained are analysed using inductively coupled plasma optical emission spectroscopy (ICP-OES) or inductively coupled plasma mass spectroscopy (ICP-MS). Specialist instrumentation is available for the determination of mercury using cold vapour atomic fluorescence and selenium, mercury, tellurium, bismuth and antimony using atomic fluorescence.
Soil chemical analysis
Soil chemical parameters are determined using a variety of extractants and analytical techniques, including:
Exchangeable cations following extraction and analysis using inductively coupled plasma optical emission spectroscopy (ICP-OES). Exchangeable acidity following extraction and titration using a Metrohmn autotitration system. From which cation exchange capacity (CEC) and base saturation are derived.
Soil pH and electrical conductivity are analysed in a range of matrices including soils, sediments, peats and waste materials.
Elemental concentrations corresponding to plant available nutrients are extracted and analysed using a variety of instrumentation, including inductively coupled plasma optical emission spectroscopy (ICP-OES), inductively coupled plasma mass spectroscopy (ICP-MS), colourimetry and ion chromatography.
Total phosphorus
Total phosphorus concentrations are determined in soil samples following fusion in sodium hydroxide and colourimetric analysis. Typically 0.1 g of milled soil is used for this analysis.
Contacts: Jason Owen.
