Stephen is a fluvial geomorphologist interested in the physical processes at work in gravel-bed rivers and the interactions between fluvial processes and river ecosystems. His research has two main strands:
Ecogeomorphology, ecohydraulics and freshwater zoogeomorphology, particularly the role of biotic energy in driving and conditioning geomorphological processes in rivers and the interactions between organisms, sediment transport and near-bed hydraulics. This includes recent work on the zoogeomorphic roles of crayfish, freshwater fish and aquatic insect larvae using a combination of field investigations and experiments at Loughborough’s River Science Laboratory.
The sedimentary structures and size characteristics of gravelly, river-bed sediments including sediment sorting and water-worked structures, bar formation processes and the links between fluvial sediments and lotic ecology. This includes ongoing work on emergent rocks as a key oviposition resource for aquatic insects, recent work on fine sediment ingress into river beds and a longstanding interest in the role of “sedimentary links” and geomorphologically significant confluences in structuring and explaining sediment characteristics and biodiversity at network scales.