Geograph - photograph every grid square

The fascination of the Afon Gwy and its associate catchment Afon Hafren afforested is the pattern of soil catenary sequences of profiles and the consequent flows of water that provide the tributary networks with concentrated flow response, this especially in the Gwy due to its configuration. Malcolm Newson published an analysis of the stream network, John Lewin developed a node system for analysis following the work of UCW Olav Slaymaker in catchment definitions and these compare to the work on rills Black Mountains, revealing structure controls and soil dominance. The great feature of Gwy is the gley soil base fed by interflow and surface wash at the tributary confluence and of Hafren of the forest ditch and regolith surrounding culverts beneath gravel formed roads. Juncus and upslope incised soil cut faces used by sheep, the farm track soil water flows and the pipe flow bursts recorded by Malcolm Newson and the deep regoltih flows assessed by Brian Knapp, add to the complex evaluated from Soil Survey and Forestry Commission and research 1968 after the Hydrological Research Unit HR Wallingford had commenced investigations, J McCulloch, John Rodda, Alan Buckman, River Authority works and Forestry Commission, Cptn. Bennett Evans. The Gwy weir had initial issues with excess to design capacity flows. Downstream the Gwy reveals some excellent rock cut water washed features along the improved road similar to some found Llyn Crafnant Reservoir, North Wales, Landscape Architecture, GCAD Cheltenham, M Spray, MD Stagg AD Pinder SH7461. The rock and flows with the access roads make their own scenery in the backdrop of conifer forest and upland pasture. It is worth reading the research papers just for their own definition of land and flows. Here the origin of river flood is apparent.