Claire McLaughlan
Email: cm645@cam.ac.uk
Tel: +44 (0)1223 336617
Research Interests
Biofilters for the improvement of reservoir quality and biodiversity
I completed my BSc (hons) degree in Biology at the University of York in 2007, and following this went on to study for a part-time MSc in Biodiversity Surveying at Nottingham Trent University. In between the two and also for my MSc dissertation, I worked with WildCRU at the University of Oxford on British macro moths and landscape-scale conservation. My interests are within the field of invertebrate ecology – I have a particular interest in invertebrates as indicators of biodiversity and ecosystem health.
Eutrophication of freshwaters is a serious problem worldwide, and in the UK eutrophic reservoirs present serious problems both in terms of water purification/supply and loss of biodiversity. Algae from the seasonal blooms caused by nitrogen and phosphorus enrichment can cause blockages in the microstrainers and sand filters used for water filtration, as well as entering the distribution pipes and creating biofilms which lead to taste and odour problems in the water supply. Blooms can also contain toxic cyanobacteria which present a risk to human health and may prevent reservoirs from being used in recreational capacities such as sailing and angling. Increased turbidity and deoxygenation of the water reduces biodiversity and alters food web dynamics. Many reservoirs have a broader conservation value as they may be important sites for migratory birds and some include SSSIs or nature reserves. Eutrophication also decreases the aesthetic qualities of a reservoir and may lower its touristic value and therefore the revenue that could feed back into conservation work.
Currently used strategies for controlling this problem include:
- Sediment dredging and subsequent dumping on land to remove phosphorus from the system
- Planting of reedbeds
- Stripping algae directly using microfiltration
- Dosing of the water with iron or copper sulphate to strip phosphorus
All of these options are expensive and several are environmentally harmful.
During my PhD I hope to explore the role which filter feeders, particularly the invasive bivalve Dreissena polymorpha (the zebra mussel) can make to the management of a reservoir. Recent work has shown that cultivating and harvesting filter feeding organisms such as mussels, which feed on phytoplankton, may be a sustainable way to recycle nutrients from water to land (see Lindahl et al. (2005) for an example of this being tested in a marine system). Zebra mussels were chosen as they are already present in the reservoirs in question and can occur at high densities with a concomitant large filtering capacity. Invasion of habitats by this species has been shown in previous work to often result in an improvement in water clarity.
Key questions:
- The optimum substrate on which to cultivate zebra mussels.
- Patterns of growth and density of mussels monitored on a monthly basis to identify optimum time for harvest.
- What effect do the filter feeders have on the macroinvertebrate benthos beneath the rigs, both in terms of community structure and diversity. Trial involving mussel ropes being tied to a floating reedbed structure at Hampton distributing reservoir, UK.
- End-use of harvested mussels: could zebra mussels be used as chicken feed or fertiliser?
- Cost-benefit analysis of the project.
My work is funded by a CASE studentship from the Natural Environment Research Council, with Anglian Water providing the case funding and field sites.
Publication
T. Merckx, R. E. Feber, C. Mclaughlan, N. A. D. Bourn, M. S. Parsons, M. C. Townsend, P. Riordan, D. W. Macdonald (2010) Shelter benefits less mobile moth species: the field-scale effect of hedgerow trees. Agriculture, Ecosystems And Environment 138: 147-151
