Laize, C.L.R.; Barker, L.J.; Edwards, F.K.

Simulated monthly biological indicators for England and Wales 1964-2012

Monthly time series of simulated de-trended/de-seasonalised biological indicators at 86 bio-monitoring sites in England and Wales based on the modelled response of these indicators to discharge (represented by a standardised streamflow index, SSI) at 76 paired gauging stations. The biological indicators include:

(i) Average Score per Taxon (ASPT)
(ii) Lotic-invertebrate Index for Flow Evaluation (LIFE) calculated at family-level (LIFE Family)
(iii) LIFE calculated at species-level (LIFE Species).

The simulation spans the period 1964-2012.

Publication date: 2018-06-27

Get the data

This dataset is made available under the terms of the Open Government Licence

Format of the data: Comma-separated values (CSV)

You must cite: Laize, C.L.R.; Barker, L.J.; Edwards, F.K. (2018). Simulated monthly biological indicators for England and Wales 1964-2012. NERC Environmental Information Data Centre.


You must acknowledge the use of Environment Agency using the following statement: © Environment Agency copyright and/or database right 2012. All rights reserved.


Study area
Temporal extent
1964-01-01    to    2012-12-31

Provenance & quality

Biological indicator ASPT and LIFE (family and species levels) were obtained for 86 sites from the EA Freshwater and Marine Biological Surveys for Invertebrates England database (commonly known as 'BIOSYS'). Biological records for the UK typically exhibit an annual positive trend and seasonal offset (higher values in spring); bio-indicators were therefore de-trended and de-seasonalised by fitting linear regression models (season and year as predictors) then subtracting the fitted bio-indicator values from the raw indicator data. Monthly SSI series for period 1964-2012 for the 76 gauging stations paired to the 86 BIOSYS sites were derived using 6-month accumulation period and Tweedy distribution. Seven predictors were assembled: SSI on same monthly date as biological indicators, and six lagged SSI (6, 12, 18, 24, 30, and 36 months prior to date of biological indicators). For each bio-indicator, a model of the indicator's response to the SSI predictors was fitted using Multi-Level modelling and Multi-Model Inference. Models were then run with the whole SSI dataset to produce the final dataset of simulated de-trended/de-seasonalised ASPT, LIFE Family and LIFE Species series for period 1964-2012.


This dataset is included in the following collections

Historic droughts: hydro-meteorological data outputs

Supplemental information

Barker, L. J., Hannaford, J., Chiverton, A., & Svensson, C. (2016). From meteorological to hydrological drought using standardised indicators. Hydrology and Earth System Sciences, 20(6), 2483-2505.

Correspondence/contact details

Dr Cedric Laize
UK Centre for Ecology & Hydrology
Maclean Building, Benson Lane, Crowmarsh Gifford
OX10 8BB


Laize, C.L.R.
Centre for Ecology & Hydrology
Barker, L.J.
Centre for Ecology & Hydrology
Edwards, F.K.
Centre for Ecology & Hydrology

Other contacts

NERC EDS Environmental Information Data Centre
NERC Environmental Information Data Centre

Additional metadata

Topic categories
ASPT,  Average Score per Taxon,  Biological Indicators,  Drought,  England Historic Drought,  LIFE,  Lotic-invertebrate Index for Flow Evaluation,  SSI,  Standardised Streamflow Index,  Wales Water Scarcity
Spatial representation type
Tabular (text)
Spatial reference system
OSGB 1936 / British National Grid
Last updated
20 May 2022 10:41