379 research outputs found

    Ecological Surveys of Welsh Lakes 2016

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    This project set out to collect, process and supply to NRW ecological and environmental data from a network of 14 lake sites across Wales, in support of NRW’s integrated monitoring programme for protected sites (SACs and SSSIs), the Water Framework Directive, Nitrates Directive, Biodiversity Action Plans and other legislative and policy drivers. In particular the surveys are aimed at informing management and restoration of protected sites and facilitating delivery of River Basin Management Plans. Using standard methods, lakes were surveyed to assess the species and abundance of aquatic plants growing within and directly around the lake and to measure water clarity, dissolved oxygen and temperature within the lakes. · The aquatic plant species are listed within the report and the complete survey results supplied to NRW as MS Excel spreadsheets. · Calculations are presented for the onward use of determining the ecological status of the lakes with respect to the Water Framework Directive (LEAFPACS). The results of the aquatic plant surveys are suitable for the purposes of assessing site condition for Habitats Directive standing water features and SSSI status. The lake metrics are applicable for the production of ecological quality ratios from which the lakes may be classified in accordance with the requirements of Water Framework Directive (2000/60/EC) Ecological Surveys of Welsh Lakes 2016 (NRW Evidence Report No. 204). Available from: https://www.researchgate.net/publication/318135626_Ecological_Surveys_of_Welsh_Lakes_2016_NRW_Evidence_Report_No_204 [accessed Sep 29, 2017]

    A palaeolimnological investigation at Crazy Well Pool, Dartmoor

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    This report presents the results from a short sediment core taken at Crazy Well Pool, Dartmoor. In addition to physical sediment analysis (loss on ignition and dry weights), siliceous microfossils (diatoms) have been used in an attempt to reconstruct lake pH changes and other water quality parameters. The core has also been dated using a technique based on the concentration of spheroidal carbonaceous particles (SCPs). The core showed a reliable chronology spanning in excess of 150 years and the diatoms were well persevered. A total of 65 species of diatom were recorded. A notable switch from benthic taxa at the base of the core to more planktonic species towards the core top was observed. Diatom pH reconstructions inferred that the lake has become slightly less acid over a post-industrial timescale, which is contrary to many other studies of UK lakes on base-poor geology. These results suggest that changes in catchment management have resulted in pH increases in the lake, despite evidence of acid deposition at the site. Information on diatom habitat requirements also suggests that lake levels have been lower in the past

    A Palaeoloimnological Investigation at Crazy Well Pool, Dartmoor. report to Westcountry Rivers Trust

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    Floating water plantain Luronium natans (L) Raf.: Current distribution and status in Llyn Padarn and Llyn Cwellyn, Wales

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    Luronium natans is native to the UK and is protected by UK and European law under Annexes II and IV of the Habitats Directive, Appendix I of the Bern Convention, Schedule 4 of the Conservation (Natural Habitats, etc.) Regulations 1994, and Schedule 8 of the Wildlife and Countryside Act, 1981. It is also listed as UK priority BAP species and the current distribution is restricted to less than 100 hectads in the UK and it should therefore be classed as nationally scarce (Lockon 2014). The main stronghold for the species is in the oligotrophic lakes of central Wales and Cumbria, as well as some canals in Wales and Shropshire (Preston et al. 2002). Due to its deep-water habit, L. natans is easily overlooked and although this may have resulted in it being under-recorded in some locations, there is also evidence of it having been lost from some lowland sites in recent years (Preston & Croft 1997). In Llyn Padarn, Luronium natans was first recorded in 1848 (Kay et al. 1999), and more recently is known to have been relatively common with records from at least 4 distinct locations reported by Andy Jones in 1997 (CCW Species & Monitoring Report No. 98/02/11 - Luronium natans (floating water-plantain) at Llyn Padarn SSSI) ( Figure 1). Survey data since 1997 are less complete. The aquatic flora was surveyed using Common Standard Monitoring methodology (JNCC 2005) for WFD assessment (Goldsmith et al. 2005, 2010, 2013), but this method does not necessitate whole-site assessment and L. natans was only recorded in one survey section at the south east end of the lake (an extensive bed from 0.8 – 2.4 m water depth). The other survey sections did not coincide with earlier L. natans records and therefore the extent of the species within the lake since 1997 has not been verified

    Inventory of ponds in the Norfolk Coast AONB - recommendations for pond survey and conservation

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    The banning of tributyltin (TBT) from boat antifouling paints in the late 1980s led to its replacement by alternative biocide additives (Voulvoulis et al., 2000; Marcheselli et al., 2010), including Cu (Dahl & Blanck, 1996) and Zn as active ingredients. It has been reported that Cu and Zn compounds associated with these biocides have caused substantial contamination of harbour and marina sediments (Eklund et al., 2010; Parks et al., 2010), with negative toxic consequences for aquatic organisms (Ytreberg et al., 2010). Indeed, it is evident that Cu and Zn compounds present in paint fragments are readily leached into the water column allowing entry into aquatic food webs (Jessop & Turner, 2011). Nevertheless, relatively little is known regarding antifoulant-derived metals contamination in freshwater lakes. The Norfolk and Suffolk Broads (Eastern England, UK) have been contaminated by antifoulant-derived heavy metals, particularly Cu and Zn which have increased since the banning of TBT (post-1987) in parts of the boated system (Boyle et al., in prep.). Further, recent studies suggest that current levels of sediment contamination by Cu may have negative ecological effects for aquatic ecosystems including inhibition of aquatic macrophyte germination and performance (Boyle et al., submitted; S. Lambert, unpublished data). In Hickling Broad (Thurne Broads system), post-TBT increases in Cu and Zn are also evident, with an interesting peak in Cu for the late 1990s in core HICK1 (Figure 1). This coincides with the large-scale loss of aquatic macrophytes (especially Characeae) from the lake in 1999 (Barker et al., 2008). HICK1 was collected in 2003. In the proposed study we sought to gain a fuller understanding of recent metal contamination in Hickling Broad up to the present day, whilst looking to verify and better contextualise the late 1990s Cu peak. Further, we aimed to determine whether the peak in Cu for Hickling Broad was also recorded at Horsey Mere which is used as a control site in this study i.e. is it just a Hickling phenomenon? Or is it a Thurne Broads system-wide effect

    DOE NIEA Standing Freshwater Monitoring of Special Areas of Conservation (SAC) and Areas Special Scientific Interest (ASSI) (Second Round) P_12324

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    This report was commissioned by the Northern Ireland Environment Agency (NIEA) and provides an assessment of the conservation status of selected water bodies within Northern Ireland. A total of 72 water bodies were surveyed, all of which were surveyed as part of the Northern Ireland Lakes Survey (NILS) (1988-1992). Nineteen of the 72 sites were surveyed in 2006 by ENSIS Ltd. as part of a similar round of assessments throughout Northern Ireland (Goldsmith et al., 2008)

    A biological survey of the Blakeney Freshes: North Norfolk

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    Blakeney Freshes in an area of low-lying grazing marsh on the North Norfolk coast, formed by the reclamation of salt marshes behind Blakeney spit (Figures 1 & 2). The area has long been recognised for its conservation value and was identified by Ratcliffe (1977) to be a Grade 1 site in the Nature Conservation Review. Reid et al. (1989) reiterated this describing the site as being of “key importance” due to it comprising of one of the most extensive areas of oligohaline-mesohaline grazing marsh in Norfolk. The marshes are particularly noted for a range of wintering and breeding birds, but also for the aquatic flora and fauna which inhabit the 25 km of drainage ditches that form a network across the site (Foster & Jackson 2000)

    A palaeolimnological study of Lake Vastadtjern, Norway

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    This project reports on analysis of a set of sediment cores collected from Lake Vastadtjern in Norway in 2013-2014, spanning a total sediment depth of c. 600 cm. Multi-proxy palaeoecological techniques, principally diatoms, macrofossils and Cladocera, were employed to assess environmental change at the lake over the last c. 6000 years. The project aims to determine ecological and chemical reference conditions of the lake to help inform the setting of reference conditions for catchments dominated by clay-rich soils

    Recent heavy metal contamination of the Thurne Broads

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    The banning of tributyltin (TBT) from boat antifouling paints in the late 1980s led to its replacement by alternative biocide additives (Voulvoulis et al., 2000; Marcheselli et al., 2010), including Cu (Dahl & Blanck, 1996) and Zn as active ingredients. It has been reported that Cu and Zn compounds associated with these biocides have caused substantial contamination of harbour and marina sediments (Eklund et al., 2010; Parks et al., 2010), with negative toxic consequences for aquatic organisms (Ytreberg et al., 2010). Indeed, it is evident that Cu and Zn compounds present in paint fragments are readily leached into the water column allowing entry into aquatic food webs (Jessop & Turner, 2011). Nevertheless, relatively little is known regarding antifoulant-derived metals contamination in freshwater lakes. The Norfolk and Suffolk Broads (Eastern England, UK) have been contaminated by antifoulant-derived heavy metals, particularly Cu and Zn which have increased since the banning of TBT (post-1987) in parts of the boated system (Boyle et al., in prep.). Further, recent studies suggest that current levels of sediment contamination by Cu may have negative ecological effects for aquatic ecosystems including inhibition of aquatic macrophyte germination and performance (Boyle et al., submitted; S. Lambert, unpublished data). In Hickling Broad (Thurne Broads system), post-TBT increases in Cu and Zn are also evident, with an interesting peak in Cu for the late 1990s in core HICK1 (Figure 1). This coincides with the large-scale loss of aquatic macrophytes (especially Characeae) from the lake in 1999 (Barker et al., 2008). HICK1 was collected in 2003. In the proposed study we sought to gain a fuller understanding of recent metal contamination in Hickling Broad up to the present day, whilst looking to verify and better contextualise the late 1990s Cu peak. Further, we aimed to determine whether the peak in Cu for Hickling Broad was also recorded at Horsey Mere which is used as a control site in this study i.e. is it just a Hickling phenomenon? Or is it a Thurne Broads system-wide effect
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