Peasants in northwestern Spain and northern Portugal set fires to get rid of encroaching vegetation and create new pasture for livestock. The region has a relatively low risk of accidental wildfires because of the humid climate and low frequency of dry storms but has the highest frequency of fires and the largest accumulated burnt area in Europe. Every summer people die caught in the middle of fire, huge amounts of money are poured into fire fighting, the landscape turns black and the smoke makes for beautiful sunsets. The government response is peculiar.
In the eighties I remember reading many newspaper headlines such as this: "One in every ten fires in Galicia intentional" [Galicia, where I live, is in northwestern Spain.] The headlines were extracted from government press releases that in the end acknowledged that "10% of fires are intentional, 90% have unknown causes." "Unknown" meant that police officers writing fire reports did not fill the "cause" box. Most newspaper readers would simply conclude that nine in ten fires were accidental or natural.
The official taboo about the causes of fires continues to this day, as does the public ignorance of the matter. But it is taking new forms, as nobody still dares to imply that fires are accidental. A few years ago, a top government official said the fires were set by "organized gangs of pyromaniacs." Another top official is now saying that the intent of people setting fires is "to sow uneasiness and to alarm society," and the Spanish Minister of the Environment, Cristina Narbona, more bluntly accuses them of conducting "forest terrorism" [although fires usually affect scrubland, rarely tree plantations, and almost never the few remaining native woodlands].
For fear of losing votes no politician dares to name farmers. Quite the opposite, politicians keep subsidizing every fat cow and every little sheep. They keep paying for expensive telephone lines, roads and school buses (often school SUV's) reaching remote farms surrounded by eroded, sometimes black, landscape. They keep paying for fire brigades so that fire does not reach the peasants' homes. And they keep glorifying the traditional rural way of life.
Here in the south of France it is understood that some of the fires are set by herdsmen in order to preserve grassland from bush encroachment. But are there more fires now in Spain or France than there were, say 100 years ago? Has the vegetation changed and become more burnable burn since then?
ReplyDeleteFire regimes change because of changes in land management practices (e.g. fire suppression in fire adapted systems), changes in vegetation composition and structure (either for anthropogenic reasons or because of the impacts of invasives species, themselves human assisted), or changes in climate.
ReplyDeleteNaturally occurring wildfires are rare in this sytem for the climactic reasons Marcelino describes, and fire is used as a management tool to maintain early successional pastureland. There appears to be little "controlled" about lighting the grasslands on fire, not as we who conduct prescribed burns understand the term, hence the escapes.
But what are they burning? The fuels that carry fire in grasslands burn hot and quick but tend to be flashy. They do not burn deep. In order to root kill shrubby old field invaders (invasive exotic or otherwise), the ideal conditions are a slow, hot groundfire with low humidity and low to moderate winds. It also matters if this happens in the dormant season or the growing season. In my experience, pastoralists burn grasslands near the end of the dormant season during dry periods to jumpstart the green growth their animals need. This is not always the best time to manage a controlled burn, howver, because these conditions tend to carry a hot fire, especially if there is wind, where it is not wanted.
As to Lars question, a great deal depends on the the forage grasses that are present. Something like Cheat Grass, an invader in teh Rocky Mt West of North America, burns with greater intensity and frequency than the native herbaceous vegetation and can alter fire regimes. Do these heavily subidized Spanish farmers have different forgae grasses - improved varieties, perhaps - than would be naturally occurring?
What about the characteristics of the burned areas that were the result of wildfires and were not existing pasture. presumeably shrubby vegetation predominated, given the remarks about bush encroachment. Has that changed from a normal fire regime, either in species composition or structure? Bush encroachment due to overgrazing in southern Africa causes native species to behave invasively. Is that the case here? Invasives love disturbance.
I don't know whether there are more fires now, and indeed I would like to know. The rural population has dwindled and many of those that remain are old and live off state pensions. So, there is probably a general carelessness about the consequences of unattended fire because little is at stake. A hundred years ago people were perhaps more careful. Perhaps they fought bush more by hand and with animals, and less with fire, than at present, and perhaps they set fires in winter instead of summer in order to better control them. In any case, we know for sure that tree cover was lower 100 years ago than at present, there was a much larger area of crops and grasslands, and there were large areas covered by shrubland, which were a result of fire and which still occupy about a third of the area of Galicia. In the absence of fire forests replace shrublands.
ReplyDeletePeasants are not burning grassland. They burn shrubland (Ulex or Erica shrubland, depending on the areas). In the long run each shepherd uses a patchwork of areas burnt in different years. Livestock forage on native grasses, herbs and tender shrub sprouts in a given patch for a few years. When shrubs cover everything again, the shepherd sets a new fire.
The peak of the fire season is usually in September, when the soil and vegetation are driest, and just before the autumn rains. The rains promote the rapid growth of livestock feed, but also heavily erode the burnt areas.
When shepherds set a fire they leave it completely unattended. Afterwards they take their livestock to the burnt areas. There is no planting or seeding or anything. The system is extremely wasteful but effortless. Burnt areas are often communal property; the community tacitly lets a few shepherds be the only users.
Other farmers may set fires simply as a cheap way to keep shrubs at a distance from their crops and small pastures.
While it may be true that most fires result from human intervention and not "natural" causes such as lightnings, one still has to ask why do they are so easily set and spread so easily.
ReplyDeleteThe climacic forest of Western Galicia and Northwestern Portugal were very probably dominated by deciduous and semi-deciduous trees which have a much lower inflamability than the heaths and gorses formations that now have extensively replaced them.
Such a landscape, whose matrix is primarily composed by pyrophilous shrubs and is deprived of a seed bank capable of furthering the ecological succession into a proper forest, seems condemned to burn easily and repetitively.
"Such a landscape seems condemned to burn easily and repetitively." Not at all. Save rare instances, it will only burn if people set the fire.
ReplyDeleteJust saw this from BBC, http://news.bbc.co.uk/2/hi/europe/4787885.stm
ReplyDeleteI wish I could find a good book on European or Mediterranean historical ecology.
Has there been a change in vegetation in Galicia to e.g. eucalyptus or pine?
Lars,
ReplyDeleteBiology and Wildlife of the Mediterranean, by Jacques Blondel and James Aronson
The Nature of Mediterranean Europe: An Ecological History, by A.T. Grove and Oliver Rackham.
I haven't read them.
In Galicia the native deciduous woodland (Quercus robur and Quercus pyrenaica) declined through history until very little was left by the 19th century and up to the present. People have planted Pinus pinaster in the lowlands for centuries, and eucalypts also in the lowlands since the end of the 19th century. Pinus radiata has been planted in the interior since the middle of the 20th century. Tree plantations are now much more abundant than the native woodland. About a third of the area of Galicia is pine and eucalypt plantations, a third is scrubland and a third is crops and other uses. Fires occur mainly on scrubland or scrubland with scattered trees.
Regarding the BBC news item, note that those arrested are not representative of people who start fires in general. Those arrested are usually, in this and previous years, mentally unstable individuals setting fires in the proximity of towns. Although it is relatively easy to identify the farmers and shepherds who start most of the fires it is seldom possible to gather evidence to formally accuse them, so they are not arrested. However, in some places and times the police has used the strategy of frequently visiting some of them to say hello and how are you and we hope there are no fires here this summer. I have been told that this "light pressure" has worked well in preventing fires at least in some places.
Thank you for the references. I only regret that I can't ask the publishers for inspection copies.
ReplyDeleteI have seen the burning of broom to create pastures in gredos and the great advantage of this system is that the broom regrows from its roos recently I have seen the broom destroyed in rectangular strips I don't know how, whether pulled up by the roots or poisoned and I am scared that with this method the broom may not regenerate.
ReplyDeleteIn a village I know in Guadalajara the trees were kept as bushes, maples of monttpellier, quercus pyrenaica and quercus faginea and this helped shepherds who used their leaf as food for live stock, now the trees are growing, maybe because the law has changed and are to high for the shepherds to cut leaf off them or for the herds to crop them.
I feel provision should be made for the shepherds, trees should be planted that can be maintained as bushes it is a healthy cheap and ecological way of feeding live stock in this country which has two bad seasons for pastures winter when the grass grows slowly and summer when the grass mattock dries getting reduced to a few buds in the leaf sheafs or on the roots. This having two seasons with poor growth of meadow plants, there are four dry mounth s in summer makes feeding livestock more expensive in the mediteranean and makes the mantaining in the old style important .If SHepherds where treated with more consideracion maybe they wouldno't be so unruly.
The use of SHeep to reseed pastures with their dejections, taking the herds onto burnt ground feilds left fallow and worn out pastures is ecologicaly interesting. The land gets reseeded with a variety of meadow plants Maybe the variety is more healthy for the animals than monocultures of pastures. Grass puts silicie in its leaves to protect itself from animales according to Roland Ennos who says no wonder cows prefer the leaves of encinas.
I consider that shepherds over pasturise for fear of fires and measures should be taken to reduce their fears and create places that aren't over pasturised, the shepherds could have more pasture and the land, very poor in most parts would get better .
People say that urbanisacion is a cause of desertificacion in Spain, I think overpasturising for fear of fires is the reason for desertificacion. Drive from madrid to barcelona and see how many hills are bare , it is not lack of rain their is enough rain in winter for meadow plants it is overpasturising which leaves the hills bare . The plants are gone over so often they can't recover from the grazingthe plant cover becomes thin and disapears and without organic material or from the heces of live stock or from dry grasses and other meadow plants the land gets so poor in nitrogen that it can't support vegetable life . Evewn the trees die in places where there are very open tradicional spainish forests . Park like lands.
The livestock owners also get benefits from the fruits of the trees , acorns serve as fattening for all live stock , in an artilce in agrocope a cordova comunity complains about the cranes eating the acorns which could have feed 70,000sheep and 4,000 pigs. JUnipers provid plentifull fruit which matures all through the winter mouths providing food for the live stock whos heces then seed entire moutain sides with these trees. The berries of pistaceos are said to be a valuable source of food for sheep full of polisacarids.Salvador Mesa Jimenez the cornetales of the sierra Magina Jaen. LOs Bosque Ibericos , Planeta.
In the centre of spain traditional farming means the clearing of natural forest . Trees here spring up everywhere or encinas oor other oaks or junipers of which their are five species in spain, palm trees in almeria, olives are a tree that forms forests if left to itself , Jesus Charco, and the local or the oficials clear the land, or completely and the trees spring up again or leaving so few trees a hectare as to make the risk of fires very low but to allow the populacion to use the trees, the wood from oaks as fire wood or in covies or pollared from a few main arms, or the beams from junipers whos wood is strong and may be used as beams when the trunks are still young and thin. much thinner than pine beams.
The centre of Spain with its dehesas of encina and sabinas its chaparal moor land of encina, hardy evergeen oak, subspecies ballota o rotundifolia, kept as bushes cut every fifteen years for charcoal and allowed to regrow from the roots are the really interesting places in Spain for those interested in forestry and fire control.
For reading about woods in Spain I suggest, Guia de arboles y arbustos de Castilla Leon Juan Ora de la RUeda, He gives lots of informacion about ways of growing trees and their uses. El Bosques mediteraneo en el norte de Africa, biodiversidad y lucha contra la desertificacion . Jesus Charco who talks of mixed jungles of olives and palmitos and completely changes your way of tinking about woods. It seems that nearly all the trees natural to Spain are found in Marroco and Algeria, and usualy treated in a similar way. The compedium of writers on spainish woods I menncioned above published by Planeta. and 'The encina en el Centro y Suroeste de España'; César Fuentes Sanchez. This book explains how to clear the forest to establish teh number of trees that are tradicional and how to prunn and care for the trees to get a maximum crop of acorns. Or to enhanc e the growth of pastures, this last in the Pedroches in Cordova.. Myself when I manage to get published.
rose macaskie