Over shorter time scales, the longevity and resilience of many species may allow them to persist in the same area. In the recent past, these processes generally occurred within a landscape locally impacted by humans but more recently, large areas of natural vegetation have been converted for other uses. Ecosystems have become fragmented and degraded, many individual species have been intensively exploited and the introduction of alien plants, animals and diseases has also caused significant problems. Against this backdrop, climate changes associated with global warming such as increases or decreases in precipitation levels and average temperatures are having increasing direct and indirect effects on many conifer species and their habitats. Impacts include more intensive or prolonged droughts, higher frequency and intensity of fires and increases in pests and disease.