The condition of native vegetation types is changed and transformed over time by land use and land management practices. Intensive natural events are illustrated which effect vegetation structure and composition in the short term. Long term interactions between intensive natural events such as firestorms, windstorms and pest animals are presented. The VAST-2 system is used to illustrate several case studies including sand mining, sheep and cattle grazing, pest animals and cropping. This lecture was given to the Fenner School, Australian National University as part of an intensive post graduate course (ENVS 2022/6012, Sustainable Systems: Rural (2015)).