Forest Fires

[C1ay]

Forest fires are natures way of cleaning house, clearing all that old underbrush and making way for fresh new growth. In a flash, nature throws a bolt of lighting and all is underway. Then man steps in and fights to put the fire out. I wonder to what extent man's interference with nature's house keeping interfers with nature itself. What do you think?

[bumab]

Look at the Great Yellowstone fire in '89 (i think). HUGE fire, much worse then it would have been due to fire suppression. Fire suppression has been blamed for many detrimental effects, such as biodiversity loss, since essenially every forest reaches a climax community and stays there, so secondary forest species suffer (although logging gives them a place).

 

I was under the impression that most fires are now left to burn, unless they threaten houses. That change came after the Yellowstone incident.

[Turtle]

___People has not always surpressed fire in North America. Not only did lightening start fires, but the native Americans regularly set fires to keep the land healthy. This pattern of burning, both forest & grassland, was only interupted when European settlers began moving in.

___So many agencies have a hand in forest management that here in Washington I don't think they have a clear policy yet. Each area requires its own unique consideration.

___Besides clearing undergrowth, fire is required for some coniferous trees to open their cones & shed their seeds; no fire, no seeds. I seem to recall Pinyon Pine is one such tree, also a staple for some native peoples.

[Fishteacher73]

The sequoya requires fire as well. Up until somewhat recently the US Forestry's position on forest fires was one of suppression. This disrupted the natural cycle (as demonstarted by the many species that require fire for their life cycles) of clearing the undrebrush and allowing a new series of succesion to occur. A natural fire (one that occurs w/ regularity and w/o built up fuel) is reasonably harmless to the community as a whole. Most animals escape, smaller fires tend to not completely burn the existing primary growth too much so that a great deal survives. Fires help recycle the nutrients stored in the brush and dead debris that accumulates (Fires tend to occur in more arid areas and this lack of moisture tends to slow the decomp. process and the fires quickly translate the lockend nutrients into readly accessable forms)).

[Buffy]

The only problem is when someone builds a house in that forest and they don't want you to burn it down anymore. The Indians didn't have a problem with this but the white folks sure did. Its amazing to see pictures of places like Yosemite Valley from 100 years ago with very few trees and now see it wall to wall trees. They have started to let fires go around the valley so there are now some big burn areas, but they'd probably make a stand on any fire inside the Valley... In the rest of California at least, its mostly let these go until they get close to developed property, but people keep building further and further into the wilderness, and of course the free-marketers want to sell off the land, rather than what they used to do which was sell you a 99 year lease. The lease should say: "You can put a building here, but if there's a fire, you lose."

 

Cheers,

Buffy

[bumab]

The sequoya requires fire as well. Up until somewhat recently the US Forestry's position on forest fires was one of suppression. This disrupted the natural cycle (as demonstarted by the many species that require fire for their life cycles) of clearing the undrebrush and allowing a new series of succesion to occur. A natural fire (one that occurs w/ regularity and w/o built up fuel) is reasonably harmless to the community as a whole. Most animals escape, smaller fires tend to not completely burn the existing primary growth too much so that a great deal survives.

 

Also, fires provide opportunities for sucestional plant an animal species to grow. Fire suppression often reduces the population of these plants, which require the increased sunlight and room that a fire provides. Some argue this is a saving grace of clear cuts and logging, which provide similar conditions, however, like Fish said, the nutrients suffer because they are taken out of the forest, instead of converted in the fire and left in place.

[Turtle]

___Something additional on the clear cutting; the replanting that follows does not usually include but one primary species. Up here in the NW, it's usually Douglas Fir. Species not replanted include the Yew, the Larch, & the Hemlock. This in itself is now a new factor to consider when planning fire in second growth areas.

___There is a challenge on up here in court as to whether loggers can harvest the burned timber from the giant Biscuit fire a couple years ago. I guess at least people are talking about this, as we here now, & that's some progress in itself.

___Remember, only You can prevent forest fires. - Smoky The Bear :(

[Fishteacher73]

Aren't they trying to sue the individual who started that fire for the costs of fighting it (Something like 30 million bucks), Turtle?

[bumab]

Oh I know, I'm not saying it's a good excuse to clear cut at all, just that it's a common reason given. I've heard of companies not relpanting in clear cuts because they want a natural sucession, but I've not heard how well that worked. The loss of biomass alone is enough to disprove that idea.

[Turtle]

___Fish, I looked a little for suit information, but didn't find it yet. :( Googling "Biscuit fire" is well...productive. This is indeed a rich topic for a thread here. :(

[Turtle]

___Just thought to add that regardless of how a forest or prairie fire starts, it's spread in rate & area is well modeled by the area of math called percolation theory. It is the case that even in large fires not every area burns, but rather pockets of unscorched plants remain.

___What will this season's fires do? :hyper:

[justforfun]

Man's interfering with nature is a part of nature. If the question is whether or not to allow fires to burn out, or even start them intentionally to clear flammable material 'safely', it depends on what you want. A forest will give up its CO2 whether or not it burns. The problem with global warming is not forests but the oil and gas which have been eliminated from the atmosphere for thousands, even millions of years. And in the last 100 years we have begun releasing all that CO2 into the air. The planet's climate will change, and people will suffer. That much seems certain.

[Boerseun]

If there's a huge backlog of CO2 in the atmosphere, won't it be absorbed into the oceans, turning the oceans acidic?

As far as I can imagine, it the oceans wont turn nearly as bad as acid rain, maybe a pH shift of 0.1 or 0.2 simply by the sheer size of the ocean surface to absorb the CO2, and the physical volume of water to distribute it in.

But then - all the carbon probably ends up in the upper atmosphere, in which case the point is moot.