THE NATURE AND RATE OF DEVELOPMENT OF CALCAREOUS GRASSLAND IN SOUTHERN BRITAIN

The nature of the plant succession from disturbed land to species-rich ancient calcicolous grassland communities was investigated by a survey of formerly disturbed sites adjacent to ancient grassland in southern Britiain. The results are compared with previous studies documenting the nature of ex-arable grasslands. This succession takes from decades to centuries to stabilise. Any apparent conservation value of recently abandoned sites is shown to derive from species which are consistently characteristic of early-mid succession. The course of succession depends on site conditions and the availability of adjacent colonisation sources. Even on skeletal soils, management such as grazing is essential; otherwise, succession proceeds towards species-poor coarse grasslands or scrub. The implications for habitat restoration and creative conservation are outlined.