Hence these increasing population densities and mounting development pressures are causing large tracks of land in the immediate surroundings of urban areas undergoing a process of what is known as urbanisation. This phenomenon directly alters forest ecosystems by removing or fragmenting forest cover. It indirectly alters forest ecosystems by modifying hydrology, altering nutrient cycling, modifying disturbance regimes, and changing atmospheric conditions. Land changes associated with urbanization also drive climate change and pollution, which alter properties of ecosystems at local, regional, and continental scales. Urbanisation has a serious affect on conifers throughout their range in both temperate and tropical regions of the world. Some of this associated disturbance is so severe that it has led to conifer species becoming Critically Endangered.