One: Disturbance in Perspective.- 1. Disturbance of grasslands - Outline of the theme.- 2. Population responses to environmental disturbance.- Two: Vegetation Response to Changing Soil Conditions.- 3. Soil variation caused by plants: a mechanism of floristic change in grassland?.- 4. Soil fertility and the composition of semi-natural grassland.- 5. Hybridization of the habitat in disturbed hay meadows.- 6. Disturbances in transplanted grasslands and wetlands.- 7. Vegetation responses to changes in tidal inundation of salt marshes.- 8. Vegetation development from denuded ground to grassland.- Three: Vegetation Response to Defoliation and Pathogens.- 9. The herbivore as prisoner of its food supply.- 10. Ecological modeling of short-term plant community dynamics under grazing with and without disturbance.- 11. Modelling the structural changes in vegetation under different grazing regimes.- 12. Restoration of species-rich grassland after a period of fertilizer application.- 13. The function of plant pathogenic fungi in natural communities.- Four: Population and Species Responses.- 14. Population differentiation in grassland vegetation.- 15. Population responses in Agrostis stolonifera to selective forces in inland and coastal habitats.- 16. A physiological analysis of genotypic variation in relative growth rate: Can growth rate confer ecological advantage?.- 17. Ecological significance of size variation within populations.- 18. Population responses of Rhinanthus angustifolius to disturbance of grassland communities.- 19. Pollination and pollen flow disturbed by honeybees in bumblebee-pollinated Rhinanthus populations?.- 20. Disturbance, hybridization and hybrid speciation.- Epilogue.- Species index.- Communities index.