Littoral Cell Definition and Budgets for Central Southern England
Keywords:
Shoreline, management, sediment, transport, erosionAbstract
Differentiation of natural process units is promoted as 8 means of better understanding the interconnected nature of coastal systems at various scales. This paper presents a new holistic methodology for the identification of littoral cells. Testing is undertaken through application to an extensive region of central southern England.
Diverse sources of information are compiled to map 8 detailed series of local sediment circulations both at the shoreline and in the offshore zone. Cells and sub-cells are subsequently defined by thorough examination of the continuity of sediment transport pathways and by identification of boundaries where there are discontinuities. Important distinctions are made between the nature and stability of different boundaries and a classification of types is devised. Application of sediment budget analysis to major process units helps to clarify the regional significance of different sediment sources, stores and sinks.
Within the study area, it is shown that sediments circulate from distinct eroding cliff sources to well defined sinks. Natural beaches are transient and dependent upon the continued functioning of supply pathways from cliff sources. Relict cells with residual circulations are identified as a consequence of interference.
Littoral cell boundaries separate independent coastal units from those that are partially, or totally dependent so the spatial impacts of various processes and practices can be discerned. They identify appropriate units for management, from which new co-operative groupings of local authorities can develop.