Hydrological Modelling of Small Scale Processes in a Wetland Habitat

O. M. JOHANSEN, J.B. JENSEN & M.L. PEDERSENAalborg University, Department of Civil Engineering - Water and Soil

Objective of this study: • To simulate the detailed flow paths in Danish river valley

containing protected rich fens and natural springs. • Understanding and quantifying the hydrological processes

is an important step towards predicting the ecological responses in these habitats

Relevance: • A planned well field close to the habitat area initiated the

investigations

Focus in presentation:• The process of gaining knowledge on the hydrological

system

PhD student Ole Munch Johansen

Location of the Lindenborg River system

Hydro-geologicalsettings

Methods

• Data collection programme

Methods

• Data collection programme • Combining local and regional distributed hydrological

models

Observation wellSpringRegional modelRich fenDetailed model

Legend0.8 km2

235 km2

Methods

• Data collection programme • Combining local and regional distributed groundwater

models• Using models and field measurements for hypothesis

testing

Methods

Spring

Supply for fish farm

Rich Fen

Main results from stationary model simulations

springRich fen

River

Limestone aquifer

Water level measurements

Main results from stationary model simulations

• Flow through rich fen: 1.2 mm/day as average surface runoff-The flow is controlled by the vertical pressure gradient

• 80 % of the discharge to the river comes from natural springs (and does not flow through the rich fens or the river valley deposits)

Recent and future work

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ModelObservations

Thank you!