Decomposers form soil from leaf litter. Temperate coniferous forests have poor soil and a colder climate. Periodic fires occur in these areas. The taiga is a very cold northern coniferous forest. Adaptations of conifers include needle shapes, year-round leaf retention, and conical tree shape.
Grasslands are temperate areas with less water than deciduous forests and more water than desert.
The more moisture, the taller the grasses. The tundra has very cold and long winters. A layer of permafrost lies beneath the surface. During the spring and summer, meltwater forms rivers and pools. Lichens are common in the treeless tundra, and animals include caribou, reindeer, lemmings, and snowy owls.