Earth and Environment

Soil and sediment analysis

 

Further information

Laboratory contact

Mr Michael Smirk


 

UWA's Earth and Environment Analysis Laboratory (EEAL) provide facilities and technicians to prepare and analyse soil samples for a range of both physical and chemical tests.

Our qualified team of technical staff are available to consult on your analysis requirements to ensure suitability of relevant analytical techniques and explain any limitations that may exist. EEAL participates in the ASPAC inter-laboratory soil analysis proficiency program and is certified for a number of tests for client quality assurance. Certified tests are carried out using standard methods from Rayment and Lyons and Chemical Methods of Australasia CSIRO publishing.Where applicable, method codes appear in brackets below.

DTPA extraction (12A1)

Using an extracting solution that contains the chelating agent diethylenetriaminepentaacetic acid (DTPA) we are able to extract micronutrients that are adsorbed onto solid phases, along with those which are water soluble.  This test is designed to mimic the action of plant roots and hence estimate micronutrient availability in soils.  Extractions are carefully performed at constant temperature, to ensure precision and accuracy of data. Resulting solutions are measured by ICP-OES with our Perkin Elmer 5300DV.

Mehlich 3 Extraction (18F1)

This multi-element soil extraction test is designed to replace a number of traditional tests for specific analytes; namely extractable P, S, Fe & Al, exchangeable cations and selected trace metals. This extraction correlates well with a number of the traditional tests and has gained popularity as a single test covering a number of parameters. It is recommended that users of this test consult the literature for comparative studies to ensure the appropriateness for their application. Analytes able to be measured include: P, Ca, Mg, Na, K, Fe, Cu, Mn, Zn, B, S, Al.

Mineral Nitrogen (7C2a)

Other available soil nutrients, such as mineral N fractions (NOx- and NH4+) are determined by automated colourimetry (using Skalar San-Plus) on aqueous extracts of soil.

Exchangeable Cations/Cation exchange capacity

Soil cation exchange capacity and exchangeable cations are measured using either the silver thiourea method (15F1-3) or a 1M ammonium acetate extraction (15D3) for exchangeable cations only. Resulting solutions are measured by ICP-OES with our Perkin Elmer 5300DV. 

Total Carbon (6B2a) and Nitrogen (7A5)

Total Carbon and Nitrogen is measured using combustion methods to analysis for Dumas C and N on the Elementar Vario Macro.  Technicians are available to run your samples; alternatively individuals may have the option to be trained in the laboratory and operating procedures.

Mineralogy and clay minerology

Semi-quantitative soil mineralogical analysis is available using the Philips PW 3020/1830 X-ray diffractometer. Additionally, this instrumentation is used for clay mineralogy, where a clay fraction is separated from the sample and specific preparation procedures are employed to identify the presence or absence of particular clay minerals.

Particle size analysis

EEAL also offers particle size analysis via one of the following methods (which will be dependent upon client requirements):

  • Laser Diffraction (Malvern Master-Sizer)
  • Sieve analysis
  • Terminal velocity (using the pipette method)
  • Loss on Ignition. 

Samples generally require pre-treatment such as organic matter removal prior to undertaking this test.  Please contact us to discuss further.

Technicians and training

Technicians are available to prepare and analyse your samples or to train approved new users to learn sample preparation, digestion/dissolution and analysis techniques.

Further testing

EEAL offer a wide variety of soil analyses, including:

  • Total and available P
  • specific surface area
  • pore size distribution
  • water holding capacity
  • soil water repellency
  • TOC/TIC
  • pH/EC.

For further details on methods and their associated benefits and limitations refer to Rayment and Lyons (2011).

Price list and request form

Contact us to discuss your analytical requirements, element options and their detection limits.