Assessing the impacts of climate change

on a chalk valley riparian wetland, UK

Andrew House13, Mike Acreman1, James Sorensen2, Julian Thompson3

1 Centre for Ecology and Hydrology, Wallingford, UK. Email: andhou@ceh.ac.uk2 British Geological Survey, Wallingford, UK 3 UCL Department of Geography, University College London, UK

The River Lambourn Observatory

600 m reach of the River Lambourn &

10 ha riparian wetland

(c) Roger Key

Conservation & scientific interest

(c) Floodplain Meadows

Partnership

Conceptual Model

House, A.R., Sorensen, J.P.R., Gooddy, D.C., Newell, A.J., Marchant, B., Mountford, J.O., Scarlett, P., Williams, P.J. and Old, G.H. (2015) Discrete wetland groundwater

discharges revealed with a three-dimensional temperature model and botanical indicators (Boxford, UK). Hydrogeology Journal. DOI 10.1007/s10040-015-1242-5

Upwelling Areas

MIKE SHE

Calibration & Validation

Calibration 1/2/2013–1/12/2013

Validation 1/12/2013–1/10/2014

ParameterCalibrated

value

Unsaturated zone infiltration rate (ms-1) 2.30 × 10-5

Peat horizontal hydraulic conductivity (ms-1) 1.98 × 10-5

Peat vertical hydraulic conductivity (ms-1) 9.53 × 10-6

Gravel horizontal hydraulic conductivity (ms-1) 2.93 × 10-4

Gravel vertical hydraulic conductivity (ms-1) 6.98 × 10-4

Manning’s n coefficient for overland flow (sm-1/3) 0.03

Model Performance

Peat heads Channel stageGravel heads

Climate Change Scenarios

HadRM3 GW

P ET

Q

Climate Change Factors

ET

GW

P

Q

Hydrological Impact: Water levels

Hydrological Impact: Flooding

Baseline HighLow

Water Level Requirements

(c) H. Zell

(c) Guido Gerding

(c) Bio-Foto

Wheeler, B.D., Gowing, D.J.G. , Shaw, S.C., Mountford, J.O. and Money, R.P. (2004) Ecohydrological Guidelines for Lowland Wetland Plant Communities (Eds. Brooks, A.W.,

Jose, P.V. and Whiteman, M.I.). Environment Agency (Anglian Region)

Ecological Impact: Vegetation

Ecological Impact: Snails

Winter Summer

0.6

0.4

-0.2

0.2

0

-0.4

-0.6

-0.8

Tattersfield, P., and McInnes, R. (2003). Hydrological requirements of Vertigo moulinsiana on three candidate Special Areas of Conservation in England (Gastropoda,

Pulmonata: Vertiginidae). Heldia, 5(7), 135-147. Snail images (c) iStockphoto LP

Conclusions

Stay tuned...

Impacts on environmental flows in

channel - fish habitat suitability

Link to nutrient/contaminant transport

model

Impacts of abstraction and site

management

Acknowledgements

Mike Acreman

Daren Gooddy

Ben Marchant

Andy Newell

Colin Roberts

Pete Scarlett

James Sorensen

Charlie Stratford

Julian Thompson

Barry Townsend

Sebastian Uhlemann

Pete Williams