Beyond the meta-ecosystem? The need for a multi-faceted approach to climate change planning on coastal wetlands: An example from South Uist, Scotland

Exposed, low-lying dune-wetland habitat complexes may have multi-faceted functionality that means they are effectively meta-ecosystems, where inter-acting nearshore, littoral, dune and freshwater components and processes must be considered together, sometimes in conjunction with interactions with contiguous inland habitats. The low-lying dune-machair-marsh-loch (lake) ecosystems of South Uist, Benbecula and North Uist in the Outer Hebrides of Scotland exhibit such functionality, and investigation of a former loch basin at the south end of South Uist has revealed an unexpected level of complexity that also identifies a particularly high exposure to climate change in the coastal hinterland, particularly in terms of water relationships, though the possibility of significant change to the coastal frontage must also be considered in contingency planning. This investigation is described by sector, then drawn together in the context of climate change. It is suggested that the environmental setting of the Uists conforms to the concept of the meta-ecosystem in spatial terms, but with additional legacy and socio-economic components, so that there is effectively a socio-spatio-temporal meta-ecosystem. It is vital that this complexity is understood and accommodated in all flood contingency and adaptation planning, and the paper attempts to assist this by presenting an overview of the functional role and context of water in the coastal lowlands of the Uists.