mountain ecology

A change in altitude up a mountain is equivalent to a latitudinal shift away from the equator, and vegetation types accordingly change with height. Thus, in the San Francisco mountains there is a change upslope from hot desert cactus at 200 m to oak scrub at 800 m. By 2000 m, the forest is coniferous shading into spruce and Douglas fir. At 4000 m, the tree line ends and Alpine tundra is encountered. Since each stage is of limited area, the full range of each biome is not represented.