Why is some degree of forest burning by fire necessary for community diversity in some ecosystems?

Question

Why is some degree of forest burning by fire necessary for community diversity in some ecosystems?

Answer 1

So plants, such as pines cones, will not start growing until they are stimulayted by high heat. The fire destroys all of the existing trees but at the same time gives rise to all of the surviving pines cones under the soil.  

Answer 2

The understory.

Forests are layered, with trees at the top and various ferns and shrubs on the forest floor. Conifers like pines and spruces need full sunshine to survive as seedlings, and burning away the ferns and bushes allows more light to penetrate to the forest floor. This is why many species of pines have cones which won't open unless heated by an open flame. If the seeds escaped onto the forest floor in deep shade, they would not survive. This is not the case in hardwood forests however. Oaks and other nut bearing trees produce large seeds with a lot of starch. This extra food helps the sapling to grow in deep shade until it is tall enough to begin to get more light. Hardwoods are not as flammable as conifers, so fire is very rare in eastern hardwood forests.

Answer 3

Here's one example that's quite specific, but really gives you an understanding of it! We learned about this in my 3rd year bio course this year.

There was a type of lizard that was living in arid, desert-like patches of a range of mountains (I can't remember which, sorry) in areas where forest fires would regularly come in and wipe out all the vegetation in the area. A group of people decided that putting out forest fires in this area was good for the environment, not realising that by doing this, they were allowing the vegetation to grow in the dry region, effectively destroying the habitat of these lizards.

Sorry for the lack of specifics, but this was an actual documented case we studied, and now the population of this species is drastically decreased. This is only ONE of the species in this area that was likely effected by putting out the fires, but we never really seem to fully understand what we've done.

Answer 4

I have read that after forest fires, the trees and grass grow back greener and more lush than before. Unfortunately, humans can get in the way of mother nature. Our planet mytifies and amazes me.