Palaeolimnological techniques are a valuable tool in determining the past ecological status of lakes. Sediment cores were collected from approximately 150 lakes to inform implementation of the EU Water Framework Directive (Bennion, 2004). This project focuses on the analysis of diatom remains in cores from 13 lakes designated as Sites of Special Scientific Interest (SSSI). For each of the cores, the fossil diatom remains from five different depths were analysed and changes in diatom assemblages investigated. The report also aimed to estimate the timescales represented by selected sediment cores using the spheroidal carbonaceous particle (SCP) dating technique. Nineteen cores from lakes in English SSSIs were chosen for analysis. Results indicate that some cores date back to at least 1850 AD, whilst for others the results were inconclusive. The report concludes that simple methods such as ordination and dissimilarity measures applied to palaeoecological data, combined with transfer functions, offer powerful techniques for defining ecological and chemical reference conditions, and assessing environmental change. SCP analysis is a valuable tool for establishing time period represented by sediment cores, although reliable chronology requires a higher number of samples per core than that used in this study. The project illustrates that relatively low resolution palaeolimnological studies can provide valuable information to aid implementation of the Water Framework Directive and development of conservation objectives for statutory designated conservation sites.
A printed copy of this report is available from our Enquiry Service. Tel: 0845 600 3078 Email: enquiries@naturalengland.org.uk