Hydrology and earth surface processes researchers at Exeter study mechanisms behind sedimentation and its links to floodwater hydraulics
Soil erosion is a major cause of environmental and agricultural problems in many parts of the world, and climate change is likely to make things worse.
But Des Walling's hydrology and earth surface processes research group at Exeter University hope that, by understanding the mechanisms behind sedimentation and its links to floodwater hydraulics and fluvial geomorphology, they will be able to decipher the impact of environmental change and human activity on the landscape.
To help them in their quest, the School of Geography and Archaeology has provided the Millennium Sedimentation laboratory.
This is an extension to the existing Amory Building and provides a state of the art sediment research facility comprised of a suite of analytical laboratories, a clean laboratory for forensic work, a tank room for conserving wood recovered from archaeological digs, rooms for sample processing and storage and offices for research staff.
It also has a two-storey experimental area which houses a 10m recirculating flume, a circular flume and a large rainfall simulator, with high level nozzles capable of generating rainfall of different intensities.
This is used to study runoff and erosion processes in soil tanks located beneath the nozzles.
The double distilled quality water needed for the four research laboratories is generated by a central water purification unit supplied by Elga LabWater, the laboratory specialists of Vivendi Water Systems. Mains water is partially deionised using a Purelab Prima 120 reverse osmosis unit which removes about 95% of the dissolved salts and 99% of organic, particulate and microbiological contaminants.
The permeate from the Prima is delivered into a 1000 litre storage tank from which it is circulated continuously through a C910 cylinder deioniser, an ultraviolet disinfection unit and a 0.2µm filter and back to the tank via a ring main which delivers the water to points of use in the laboratories. The C910 cartridge is filled with mixed bed ion exchange resins and produces water of conductivity less than 1µS/cm - high enough quality for the analytical procedures used for soil and water analysis.
When it is exhausted it is simply returned to Elga LabWater in exchange for a new one, completely eliminating the need to handle regenerant chemicals.
The university has a number of Elga LabWater units.
"It's good quality laboratory kit and well priced." says Mike Trimmer of the university's estates department.
"With limited research grants we need results quickly, and we can't afford to have equipment down even for short periods," he goes on, "Vivendi Water Systems are very fast on service and that's another reason we use them." And Vivendi Water Systems is pleased to be helping Exeter to remain a world leader in sediment research.
