Forest factsBotany quiz
This kind of tilted forest is a common sight in subarctic taiga. What is this phenomenon caused by?
The soil. The permafrost prevents trees from developing a deep root system. Climate variations or forest fires can thaw the upper extents of the permafrost, creating a ground slump called thermokarst.
How many percent of the world's land is occupied by forests?
31%. Forests cover 31 percent of the world's land surface, just over 4 billion hectares. (One hectare = 2.47 acres.) This is down from the pre-industrial area of 5.9 billion hectares.