The UK's sustainable future rests on a holistic appraisal of rural landscape function/land use and the state of critical ecosystem services [1]. In upland Britain, important concerns include moving towards net-zero carbon targets for land-use, increasing the forest estate, and maintaining or enhancing biodiversity while supporting upland farming. Planning is better informed by knowledge of recent change in the upland system related to the large-scale social and economic transformations of the 20th Century. This project focuses on Snowdonia, a mountainous region of North Wales that includes the extensive Snowdonia National Park. Here, a range of human impacts (for example, deforestation, moor burning, afforestation, fluctuating levels of grazing pressure, and pasture improvement) have affected the landscape-scale mosaic of vegetation cover and inputs and outputs of carbon, nutrients and pollutants to upland waters and downstream locations. The link between land use/farming/forestry practices of the past ca 150 yr and carbon storage potential in peat/quality of inland waters can be demonstrated using modern palaeoecological techniques applied to peat and lake sedimentary records. The work would contribute to the development of upland land-management strategy in partnership with Natural Resources Wales (Bangor).