High quality diatom analysis

Freshwater diatoms are a key component of the Water Framework Directive (WFD) classifications of lakes and rivers and because of their sensitivity to nutrient levels are very useful indicators of eutrophication. Diatoms can also be used to detect other environmental pressures such as increased acidity.

Our team of diatom specialists has a wealth of experience in identifying diatom samples from all types of water bodies across the UK, as well as coastal waters.

Scientists in laboratory

Contracts can be large, such our analysis of almost 1,000 samples for the Environment Agency’s WFD monitoring in 2013-14; or small, such as the analysis of eight samples in 2016 for a Natural Resources Wales wetland restoration project.

The quality of our work is demonstrated by our consistently accurate results in the UK and Ireland Ring Test, in which all our analysts participate. Participation in the ring test is a prerequisite for undertaking contracts with the UK regulatory bodies.

  • Close up of marine diatom under the microscope
  • Close up of diatom
  • Close up of diatoms
  • Close up of marine diatom

Laboratory processes

We are fully conversant in WFD compliant methods of diatom sample collection, slide preparation and enumeration of prepared diatom slides. Our laboratory in Stockport is fully equipped to deal with the processing of raw diatom samples and the creation of permanent slide mounts for all types of diatom samples.

This process is subject to batch control, which ensures samples are rejected and re-processed if statistically significant levels of contamination are found.

We are experienced in the use of the DARLEQ2 tool, which provides observed and expected values of both the trophic diatom index and DAM metrics, for nutrients and acidity respectively. This contributes to assessments of waterbodies that are compatible with the standards used under the WFD.

We provide interpretative reporting of DARLEQ2 outputs and this is supported by our ecological knowledge of the responses of diatom communities to various pressures, which may be lost by focussing only on the bare metrics.

We can also provide analysis of coastal marine samples and lake sediment core samples.

If you have any queries, please contact David Hall, head of laboratories.
Alternatively you can email us here. Or call 0161 442 8938.