Chalk streams in the Chilterns: their richness and the many problems facing them.

CHANGE OF TIME: Talk will now start at 6pm

Chalk streams are habitats of a significant richness. They support some of the most threatened plants and animals in England. Chalk streams are fed from groundwater held in the chalk. Since groundwater levels in the chalk depends on rainfall and season, chalk streams are naturally intermittent in their flow. The talks will focus on the importance of Chalk streams and the characterization of its hydrological intermittence.