Creative pyromania

The best way to avoid the repetition of Valencia et al's disastrous forest fires and create walkable woodlands.

Fires in Murcia and Valencia 2/7/2012 (N = right). CC Terra@Nasa. More.

I've only been walking in Spanish forests for a decade, but even in that period a decline in their recreational use and maintenance has been noticeable. Reflecting the monomaniacal obsession with the Camino de Santiago, a few paths have become extremely popular but most are rarely used and a considerable proportion have become inaccessible, passing through overgrown woods with comparatively low biodiversity. It is well-known that dogshit stops 20 metres from the obesemobile-park, and not many of our clients choose to venture beyond the city limits. This tendency has been exacerbated by a steady decline in agriculture, blah blah blah... But why listen to an ignorant fool instead of Boris Vannière et al, A fire paradox in ecosystems around the Mediterranean:

The paleofire record from the Mediterranean is paradoxical. Climatic variations have certainly acted as one of the main pacemakers of fire regimes, particularly in the first half of the Holocene. Under different climate conditions (e.g., seasonality of precipitation), the southern and northern Mediterranean may have been differentially impacted by fire. Similarly, human actions (e.g., directly via ignition or indirectly via fuel management) have both increased and decreased fire activity during the Holocene. Increased sedimentary charcoal influx is often associated with pre- and proto-historic forest clearance but in the late Holocene, wildfire frequency often reached a maximum during phases of land abandonment and secondary scrub-woodland development, e.g., during the last century in much of Mediterranean Europe. Even apparently well established relationships, such as evergreen oaks being favored by fire, turn out to be wrong when viewed over decadal to centennial timescales. These complex long-term responses are significant in the context as well as major regional land-use changes linked to agricultural and tourism development around the Mediterranean Sea. Understanding them will help us to better manage and preserve one of the most fire-prone regions of the world, characterized by extraordinary plant diversity.

Preventative pyromania is cheap and effective though still taboo in Spain - ¡pobres animalitos! ¡trees are sacred! Learning from California's disastrous record of fire suppression - instead of repeating West Coast hippy mantras - might enable us to avoid repeating their errors, cut emergency budgets and create pleasant, usable forests. A paper the other week from UC Berkeley, The Effects of Forest Fuel-Reduction Treatments in the United States, made more or less these points:

The current conditions of many seasonally dry forests in the western and southern United States, especially those that once experienced low- to moderate-intensity fire regimes, leave them uncharacteristically susceptible to high-severity wildfire. Both prescribed fire and its mechanical surrogates are generally successful in meeting short-term fuel-reduction objectives such that treated stands are more resilient to high-intensity wildfire. Most available evidence suggests that these objectives are typically accomplished with few unintended consequences, since most ecosystem components (vegetation, soils, wildlife, bark beetles, carbon sequestration) exhibit very subtle effects or no measurable effects at all. Although mechanical treatments do not serve as complete surrogates for fire, their application can help mitigate costs and liability in some areas. Desired treatment effects on fire hazards are transient, which indicates that after fuel-reduction management starts, managers need to be persistent with repeated treatment, especially in the faster-growing forests in the southern United States.

Unfortunately article access is not free (why not?!), but there's a slightly more wideranging summary here. Here's the last chunk:

Stephens noted that two-thirds of the fuel-reduction treatments in the western United States rely upon mechanical thinning, which would be much more costly than prescribed burns to scale up. In the southeast region, the use of prescribed fire dominates.

In the West, particularly in California, the biggest challenge to expanding controlled burns is the potential reduction in air quality during treatment, said Stephens.

“We have a choice,” he said, “of dealing with lower levels of smoke from prescribed fires that may only be needed every 15 years or so, and which can be timed for optimum wind conditions, or acute levels of smoke from catastrophic fires that can last for months when they hit.”

Perhaps massive mob use of fireworks on St John's Eve could be strategically redeployed to target rural zones, earlier in the year.

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1. Náiguel Puig i Clot says:

   July 3 2012 at 13:05

   Roun dese parts, the locals put the blame on the biologists. When engineers ran the park, they cleaned the forest floor so that fires wouldn't spread via exploding pine cones, for example. The ecologist types not only don't do that, they've gone so far as to prohibit that anyone do it. Catch you with a bag of cones to light your fireplace - big trubba, bumbo.

2. Mr Baldie says:

   July 3 2012 at 13:24

   I prefer the older, misspelled prohibitions on pine cone gathering of the "Do you like hospital food?" variety - locals trying to stop you nicking their pine nuts.

3. Mr Baldie says:

   July 6 2012 at 22:33

   http://www.wired.com/wiredscience/2012/07/western-fire-transformation/

   Because small, low-intensity blazes are usually prevented from spreading, dead wood has accumulated, especially in arid and semi-arid regions where decomposition occurs slowly. Without these fires, dense shrubs and small trees proliferate, as they also do in gaps opened by harvesting of large trees. Grazing removes grasses that traditionally carried small fires and causes erosion that reduces soil’s ability to hold water.

   'The fuel structure is ready to support massive, severe fires that the trees have not evolved to cope with.'
   – Dan Binkley
   Much of the West is now a giant tinderbox, literally ready to combust. Yet thanks to fire suppression, the consequences have been postponed for decades.
   “When you look at the long record, you see fire and climate moving together over decades, over centuries, over thousands of years,” said pyrogeographer Jennifer Marlon of Yale University, who earlier this year co-authored a study of long-term fire patterns in the American West.

   “Then, when you look at the last century, you see the climate getting warmer and drier, but until the last couple decades the amount of fire was really low. We’ve pushed fire in the opposite direction you’d expect from climate,” Marlon said.

   The fire debt is finally coming due. In the Southwest, fires are reaching historically exceptional sizes and temperatures. “The fuel structure is ready to support massive, severe fires that the trees have not evolved to cope with,” said forest ecologist Dan Binkley of Colorado State University. “When the extent of the areas burned becomes large, there are no remaining sources of seeds for the next generation.”