The University of Southampton
University of Southampton Institutional Repository

Assessing lake eutrophication using chironomids: understanding the nature of community response in different lake types

Langdon, Peter G., Ruiz, Zoe, Brodersen, K.laus P. and Foster, Ian D. L. (2006) Assessing lake eutrophication using chironomids: understanding the nature of community response in different lake types Freshwater Biology, 51, (3), pp. 562-577. (doi:10.1111/j.1365-2427.2005.01500.x).

Record type: Article

Abstract

1. Total phosphorus (TP) and chlorophyll a (Chl a) chironomid inference models (Brodersen & Lindegaard, 1999; Brooks, Bennion & Birks, 2001) were used in an attempt to reconstruct changes in nutrients from three very different lake types. Both training sets were expanded, particularly at the low end of the nutrient gradient, using contemporary chironomid assemblages and environmental parameters from 12 British lakes, although this had little improvement on the model performances.
2. Dissimilarity analyses showed that the historic chironomid assemblages did not have good analogues in the original calibration or extended datasets. However, since the transfer functions are based on weighted averages of the trophic optima for the taxa present and not on community similarities, reasonable downcore inferences were produced. Ordination analyses also showed that the lakes retain their 'identity' over time, as the sample dissimilarities within lakes were less than the dissimilarities between lakes.
3. Analysis of the three historic lake profiles showed a range of chironomid community responses to lake development. Chironomids from a shallow lake, Slapton Ley, responded indirectly to nutrient enrichment (TP), probably through altered substrate, macrophyte and fish conditions, rather than directly to primary productivity (Chl a). A stratified lake, Old Mill Reservoir, showed a loss of the profundal chironomid fauna due to increasing primary productivity (Chl a) coupled with increasing hypoxia. A response to nutrients (TP or total nitrogen (TN)) at this site is also indirect, and the TP reconstruction therefore cannot be reliably interpreted. The third lake, March Ghyll Reservoir has little change in historic chironomid communities, suggesting that this well mixed, relatively unproductive lake has changed less than the other lakes.
4. Using chironomids to reconstruct nutrient histories does not follow a simple scheme. The response to changes in nutrients may be direct, but mediated through other ecosystem components. As alternative stable states are possible at a given level of TP it is also likely that alternative chironomid communities exist under similar nutrient conditions. Changes in biological communities can thus occur over thresholds, and it is only biological proxies that can reflect such ecosystem switches within palaeoenvironmental investigations.

Full text not available from this repository.

More information

Published date: March 2006
Additional Information: This innovative paper documented the first use of chironomid-inferred total phosphorus and chlorophyll-a transfer functions to assess the nature of past eutrophication on a range of lake types. It explored a range of model responses and identified complex responses to changes in lake functioning. NERC funded research, new investigators award.
Keywords: chironomids, chlorophyll a, eutrophication, total phosphorus, transfer functions

Identifiers

Local EPrints ID: 37829
URI: http://eprints.soton.ac.uk/id/eprint/37829
ISSN: 0046-5070
PURE UUID: b41e6f3e-c78d-4514-bd2c-3490c3fa182b
ORCID for Peter G. Langdon: ORCID iD orcid.org/0000-0003-2724-2643

Catalogue record

Date deposited: 26 May 2006
Last modified: 17 Jul 2017 15:41

Export record

Altmetrics

Contributors

Author: Zoe Ruiz
Author: K.laus P. Brodersen
Author: Ian D. L. Foster

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×