UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Assessment of ecological status in UK lakes using benthic diatoms

Bennion, H; Kelly, MG; Juggins, S; Yallop, ML; Burgess, A; Jamieson, J; Krokowski, J; (2014) Assessment of ecological status in UK lakes using benthic diatoms. Freshwater Science , 33 (2) 639 - 654. 10.1086/675447. Green open access

[thumbnail of Bennion_Assessment_of_ecological_status.pdf]
Preview
Text
Bennion_Assessment_of_ecological_status.pdf

Download (503kB) | Preview

Abstract

The European Union’s Water Framework Directive (WFD) requires that all water bodies in Europe achieve good ecological status (GES) by 2015. We developed an ecological classification tool for UK lakes based on benthic diatoms, a key component of the biological-quality element macrophytes and phytobenthos. A database of 1079 epilithic and epiphytic diatom samples and matching environmental data was assembled from 228 UK lakes. The data set was divided into 3 lake types: low, medium, and high alkalinity. A lake trophic diatom index (LTDI) was developed based on modification of the trophic diatom index (TDI) for rivers, and ecological quality ratios (EQRs) were generated for each lake type. The high/good status boundary was defined as the 25th percentile of EQRs of all reference sites (identified based on independent sedimentary-diatom-assemblage data or catchment point-source and landuse data), whereas the good/moderate boundary was set at the point at which nutrient-sensitive and nutrient-tolerant taxa were present in equal relative abundance. The moderate/poor and poor/bad boundaries were defined by equal division of the remaining EQR gradient. Samples from reference sites were used to predict the expected LTDI value for each sample, and these values were compared with the classifications derived from the LTDI. For lakes identified as reference sites, 68% were classified as having high status and 32% as having good. The model predicted 81% of nonreference lakes to have good or worse status. The model was applied to 17 English lakes (10 low- and 7 medium-alkalinity) for which classification based on other WFD tools was available. The classifications based on LTDI gave the same status (within 1 class) as other biological elements for 11 of the 17 lakes (65%). Thus, the LTDI gives a reliable assessment of the condition of the littoral biofilm and is a key component of a WFD-compliant tool kit for classifying UK standing waters.

Type: Article
Title: Assessment of ecological status in UK lakes using benthic diatoms
Open access status: An open access version is available from UCL Discovery
DOI: 10.1086/675447
Publisher version: http://dx.doi.org/10.1086/675447
Language: English
Additional information: © 2014 by The Society for Freshwater Science.
Keywords: diatoms, phytobenthos, lakes, Water Framework Directive, ecological status, nutrients, metrics, reference conditions
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL SLASH
UCL > Provost and Vice Provost Offices > UCL SLASH > Faculty of S&HS
UCL > Provost and Vice Provost Offices > UCL SLASH > Faculty of S&HS > Dept of Geography
URI: https://discovery.ucl.ac.uk/id/eprint/1435451
Downloads since deposit
358Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item