Welsh Journals

SHEEP GRAZING EXPERIMENTS IN SNOWDONIA J. DALE INTRODUCTION Clearance of native deciduous forest to provide fuel and timber and to create grazings for domestic stock has moulded the present day landscape of upland Wales. This landscape is artificial, resulting from human modification of the environment (Moore and Chater 1969). The human influence together with the complexity of the geology and consequent diversity of soils and vegetation, matched with equally diverse ranges of local climate, physiography and altitude make the mountains of Snowdonia particularly suitable as a base for ecological research. THE RESEARCH PROGRAMME Investigation of the influence of climatic and geological variation within Snowdonia upon its soils, vegetation, biological productivity and land use, is the main theme of The Nature Conservancy's researches in the mountains of North Wales. Besides the strictly academic value of this work, it also has important practical implications in the field of conservation and the multi-purpose use of land (Land Use Study Group Report 1966). The force of the human impact on the environ- ment is increasing each year and the demands of agriculture, forestry, conservation, recreation, housing and industry are becoming more competitive, and the overall demand for land for these purposes is reaching almost insatiable proportions. Clearly, the available land must be utilised to the best advantage for the community as a whole and the apparently conflicting demands of one faction must be integrated with those of others, within a land utilisation plan which takes into account ecological considerations. Some aspects of the studies being conducted from The Nature Conservancy's Research Station at Bangor can contribute to the formulation of such plans. ENVIRONMENT AND VEGETATION IN SNOWDONIA The soils of Snowdonia are derived from acidic and basic volcanic and sedimentary rocks of Ordovician age together with those derived from glacial drift. The soils range in type from acidic brown earths associated with basic pumice tuffs and dolerites, through intermediate soil types to podsolised soils and peat rankers associated with the acidic rhyolites. Glacial drift soils are much affected by the nature of the preponderant rock types contained within them. Throughout the whole range, with increasing rainfall the brown earth soils show tendencies towards podsolisation. On the brown earth soils the vegetation is usually Agrostis- Festuca grassland, with varying proportions of herb species present.