Phytobenthos are good indicators of nutrient enrichment and can be used to assess lake water quality. Diatoms are the main plant groups that we use because their silica cell walls make them easy to identify under the microscope. The method is based on the principle that different diatoms have different environmental preferences, so we record the species found, along with their abundance.
The latest version of the DARLEQ tool is version DARLEQ 2.0.1, updated 06/08/2014. Click on DARLEQ2Setup.zip to download the tool.
NB There are some amendments to the EQR boundaries for lakes (and rivers) in the July method statement. These have been revised in the December version.