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Forest Fires in Portugal: Dynamics, Causes and Policies

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With a mean annual fire incidence of 3% of its forest and wildland surface Portugal is the European country most affected by wildfire. Forest fires dynamics in Portugal in the last four decades are presented (the fire regime and the corresponding losses) as well as the corresponding socioeconomic, environmental and policy drivers. The 20th century and on-going changes in land use (afforestation and rural abandonment) and climate are described. The policy options, strategies and plans established and implemented after the extreme forest fire seasons of 2003-2005 are discussed. Fire suppression is currently prioritized over fire prevention. However, the fire problem is rooted in in the socioeconomic factors behind fire occurrence (namely land use conflicts) and in the prevalence of unmanaged and flammable vegetation types. Forest and land management and civil protection have different objectives and both need to be tackled for effective mitigation of wildfire impacts. Managing vegetation to induce higher fire-resilience and changing human behaviour are needed and must be fully encouraged and supported. It follows that the current relative allocation of resources should shift from fire suppression to fire prevention under an integrated fire management philosophy. Mitigation of the wildfire problem depends on institutional stability and persistence in following a coherent fire management policy.
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CHAPTER 4
FOREST FIRES IN PORTUGAL: DYNAMICS, CAUSES AND POLICIES
Paulo Mateus* & Paulo M. Fernandes**
*Instituto da Conservação da Natureza e das Florestas, Estrada Exterior da Circunvalação, 11846,
4460-281 Senhora da Hora, Portugal
**Centro de Investigação e de Tecnologias Agro-Ambientais e Tecnológicas (CITAB) &
Departamento de Ciências Florestais e Arquitectura Paisagista, Universidade de Trás-os-Montes e
Alto Douro, Quinta de Prados, 5000-801, Portugal
(**) Corresponding author: pfern@utad.pt
Abstract
With a mean annual fire incidence of 3% of its forest and wildland surface Portugal is the European
country most affected by wildfire. Forest fires dynamics in Portugal in the last four decades are
presented (the fire regime and the corresponding losses) as well as the corresponding socioeconomic,
environmental and policy drivers. The 20th century and on-going changes in land use (afforestation
and rural abandonment) and climate are described. The policy options, strategies and plans established
and implemented after the extreme forest fire seasons of 2003-2005 are discussed. Fire suppression is
currently prioritized over fire prevention. However, the fire problem is rooted in in the socioeconomic
factors behind fire occurrence (namely land use conflicts) and in the prevalence of unmanaged and
flammable vegetation types. Forest and land management and civil protection have different objectives
and both need to be tackled for effective mitigation of wildfire impacts. Managing vegetation to
induce higher fire-resilience and changing human behaviour are needed and must be fully encouraged
and supported. It follows that the current relative allocation of resources should shift from fire
suppression to fire prevention under an integrated fire management philosophy. Mitigation of the
wildfire problem depends on institutional stability and persistence in following a coherent fire
management policy.
Key words: Fire regime; Fire management policy; Fire prevention; Fire suppression
1. Introduction: the Portuguese fire regime
Forest fires are the most significant threat that forests and wooded areas in southern Europe face,
and the problem can escalate with climate change and the persistence of land use changes that
reinforce landscape-level flammability (Moreira et al. 2011; Fernandes 2013). Wildfires affect both
ecosystems and human communities, with potential major negative environmental and socioeconomic
consequences. Wildfires are currently the main forest disturbance and are among the main
environmental concerns in Portugal. However, the threat posed by significant fire events is not new,
e.g. Goes (1977) mentions several large fire incidents in the 1960s, including a mega-fire in southern
Portugal with “thousands of hectares” and a length of 40 km.
Fire is a disturbance arising from a combination of natural and anthropogenic factors whose
spatiotemporal characteristics (the fire regime) can be described and quantified (Gill and Allan 2008).
The fire regime can be characterized in terms of extent, the % annual area burned whose reciprocal is
the fire rotation period, i.e. the time needed to burn an area the size of the study region; frequency,
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which determines the fire return interval, the average period of time between consecutive fires in a
given area; severity, the magnitude of the effects caused; and seasonality. The fire regime concept is a
central tenet in fire ecology and management and regional comparisons enable to understand which
drivers determine and constrain (or favour) fire activity, in turn allowing the delineation of fire
management strategies and policies.
Table 4.1 Comparative wildfire statistics (2000-2011) between southern Europe countries. Produced
with data supplied by the European Forest Fire Information System
(http://forest.jrc.ec.europa.eu/effis/)
Country
Ignition density Burnt area Mean fire % fires >500 ha
(no. 100 km
-2
)* (%) ** size >1 ha No. Area
Portugal 24.0 a 2.84 a 24.5 b 0.80 ab 42.4 ab
Spain 3.5 b 0.53 b 18.4 b 0.46 b 35.2 ab
France 0.7 bc 0.10 b 14.6 b 0.41 ab 29.7 ab
Italy 2.3 bc 0.66 b 16.4 b 0.28 b 16.4 b
Greece 0.7 c 0.53 b 90.3 a 2.07 a 48.2 a
* >0.01 ha in size. ** In relation to forest, woodland and shrubland area.
Means followed by the same letter are not significantly different (p>0.05), Tukey-Kramer
HSD test.
We will start by characterizing the Portuguese fire regime. All figures result from the analyses of
official data, be it fire records and maps, the national forest inventory or fire danger rating data.
Portugal is the country most affected by forest fires in the Mediterranean Basin (Table 4.1), with no
discernible temporal shifts towards less area burned like observed elsewhere, e.g. Spain (Moreno et al.
2013). The Landsat-based national fire atlas (Oliveira et al. 2012) indicates a cumulative burned area
of 4.2 x 10
6
ha between 1975 and 2012 (Figure 4.1). An annual average of 1.4 x 10
5
ha was burnt in
the 2000-2011 period, corresponding to 3% of the wildland area, or to an average fire rotation period
of 30 years (Table 4.1). Burn probability is predicted reasonably well from past fire recurrence, slope
and land cover type (Verde and Zêzere 2010). The regions that experience higher fire incidence, burn
at an average rate of 6% per year, or with an average fire rotation period of 17 years (Vilén and
Fernandes 2011). Both the absolute and relative values are the highest among southern Europe
countries, which is primarily an outcome of the extremely high ignition density and the relevance of
fires larger than 500 ha (Table 4.1) further exacerbates. Medium-to-large fires, i.e. >100 ha, are of
special concern because of the associated damage, and accounted for 93% of the area burned in 2003,
the most extreme fire year.
Ignition density and area burned are spatially decoupled in Portugal. While the former is highly
correlated with population density and is especially high around the urban centres of northwest
Portugal (Catry et al. 2009), the latter coincides with higher elevations and steeper terrain, prevalence
of shrubland and lower population density in the north and centre of the country (Marques et al. 2011).
National fire planning (Lourenço 2005) classifies municipalities in one of four types depending on the
combination of ignition density (low or high) with area burned (low or high), which helps in defining
fire management goals and approaches.
The fire return interval is critical to forest management, namely regarding investment decisions in
the establishment and tending of plantations managed for forest products. Burn probability, either
expected from fire history, or perceived by forest managers, plays a role in the selection of species for
afforestation. For example, a low fire return interval (let’s say <20 years) favours the plantation of
fast-growing species, e.g. blue gum (Eucalyptus globulus) in Portugal, which in spite of being an
exotic is nowadays the most expanded forest type in the country. An even higher frequency of fire will
impede forest persistence and shift the landscape towards dominance by shrubland or grassland.
Conversely, higher fire return intervals (>40 years) support the option for pine plantations or relatively
slow-growing oak species. The mean and median fire return intervals (1975-2005) in Portugal are 36
3
and 28 years, respectively, and are lower than 25 years in most of northern Portugal (Oliveira et al.
2012). However, areas burnt two or more times in the north western mountains of the country are
characterized by a fire-free interval of 12-15 years (Fernandes et al. 2012). Figure 4.1 shows the area
burned from 1975 to 2012 by classes of fire recurrence, i.e. the number of times each patch burnt.
More than half (56.8%) of the mapped fire scars area result from a single fire event, which equates to a
fire return interval of 38 years, compatible with forest production. Areas burned 2-3, 4-8, and 9-15
times respectively represent 33.5, 9.5 and 0.2% of the total burned area.
Fig 4.1
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Table 4.2 reports burned area in Portugal by land and forest cover type (1996-2012). More than two
thirds of the burned surface respects to non-forest cover types, especially shrubland. Maritime pine
(Pinus pinaster) and blue gum (Eucalyptus globulus) are flammable forest types that dominate
northern and central Portugal and accounted for 77% of all forest burned. The other forest species do
not contribute substantially to area burned due to low representativity (e.g. deciduous hardwoods) or
because they occur in more fuel-limited landscapes and where ignition rates are low (sclerophylous
oaks). A better depiction of the vulnerability to fire can be obtained by calculating fire-preference
indexes, calculated from the area burned by vegetation types in relation to their abundance.
Nationwide statistics indicate that Ceratonia siliqua, evergreen oak woodland and Pinus pinea are
avoided by fire, whereas Pinus pinaster, Eucalyptus globulus and deciduous oaks are preferred by fire
(Table 4.2). Depending on the method useds, fire-preference analysis focused on individual fires
shows that shrubland is far more selected by fire than forests, and that maritime pine stands are more
fire prone than the other forest types (Moreira et al. 2009), or that evergreen oaks and eucalypts are
avoided by fire whereas pines and shrublands are preferred by fire (Barros and Pereira 2014). Fire
selectivity tends to decrease with fire size (Nunes et al. 2005; Barros and Pereira 2014).
Table 4.2 Area burned in Portugal, distribution by land and forest cover types, and preference by fire.
Based on ICNF data (http://www.icnf.pt/portal/florestas/dfci/inc/estatisticas) (1996-2012)
Tipo
Burned area
(10
3
ha) %
Forest type index of
preference by fire
Shrubland 587.3
32.1
Grassland 329.7
18.0
Forest 645.6
35.3
Pinus pinaster 266.9
41.3 0.35
Eucalyptus globulus 231.6
35.9 0.29
Quercus suber 33.8
5.2 -0.68
Quercus rotundifolia 18.5
2.9 -0.60
Deciduous oaks
24.8
3.8 0.26
Pinus pinea 10.0
1.5 -0.52
Castanea sativa 4.1
0.6 -0.29
Ceratonia siliqua 0.1
0.0 -0.90
Acacia spp.
1.1
0.2 0.13
Other broadleaves
25.0
3.9 -0.15
Other conifers
18.3
2.8 0.15
Undetermined
11.5
1.8
Other land cover types 268.7
14.7
Total
1831.2
100.0
Fire activity concentrates essentially in June-September (90% of the area burned), but depending on
drought patterns is not negligible in autumn-winter months (especially October and March) wherever
pastoral burning is a component of land management. This seasonal pattern, the prevailing dry
condition of the dominant vegetation types, relatively high plant productivity, and the relevance of
shrubs in the fuel complex whether as shrubland or forest understorey imply that fire severity is
generally high. Most fires are stand-replacement crown fires.
In the remainder of this chapter we will address the negative impacts of wildfires in Portugal,
describe their structural causes (including the instability in policies and agencies) and then focus on
current fire management and its development prospects.
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2. Fire-caused losses
Death of people is the most dramatic consequence of wildfires. Fire-related human fatalities are
unfortunately a regular event in Portugal, especially of fire fighters that perish while facing the fire or
in accidents, and of senior farmers victimized by land use-related fires. 97 human lives were lost from
2002 to 2013 as a direct result of rural fires, of which 47% were civilians and 53% were fire fighters.
In addition, more than one thousand people reportedly needed medical assistance because of smoke
inhalation, burns, wounds and other fire-related problems during the extreme years of 2003 and 2005.
The true dimension of the wildfire problem can be assessed through its social cost, which is the
most negative of the forest-related externalities. Ecosystem services such as biodiversity conservation,
soil and water conservation and carbon storage should be considered. The total economic value of
forests and wildlands was 1.3 x 10
3
in 2001, or 344 € ha
-1
year
-1
, and the figures that follow respect
to 2000-2004 (ISA 2005). The social cost of wildfires ranged between 0.2 and 1.0 x 10
3
€, i.e. 20 to
80% of the annual forest production (Table 4.3). The costs of fire management were 600 € per hectare
of burned land, and the costs associated to the loss and post fire restoration of assets and services
reached 3500 per hectare of burned forest. The annual mean investment in fire management was
18.3 € per hectare of the existing forest and wildland, with a nominal suppression-to-prevention ratio
of 2.2:1. However, we estimate that fire pre-suppression and suppression absorbed 94% of the fire
management budget in 2010.
Figure 4.2 depicts the evolution in time of area burned in Portugal, 1980-2012, indicating an
increasing trend until the mid-2000s, followed by a slight decrease. However, a less marked temporal
trend would result from excluding the abnormal years of 2003 and 2005. Given the afforestation effort
and annual volume growth, an annual burned area of 25,000 ha (ca. 0.8% of forest surface) is the
threshold to sustain forest production in Portugal (DGRF 2007), but 24 of the last 33 years exceeded
this figure. Damage to forest stands exceeded 10
5
ha in 1991 and 1995 and was particularly severe in
2003 (2.9 x 10
5
ha, 8% of forest cover) and 2005 (2.1 x 10
5
ha); burned areas lower than 10
4
ha were
restricted to 1988, 2007 and 2008. Maritime pine and blue gum are the major sources of wood
products, implying that the high fire incidence to which they are subjected shifts stand age distribution
towards younger classes, decreasing the amount of round wood available for sawn and decreasing the
eucalypt industry interest in the production of pulp (Rego et al. 2013).
Fig 4.2
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Table 4.3 The social costs of wildfires in Portugal from 2000 to 2012*
Cost
(10
6
€) 2000 01 02 03 04 05 06 07 08 09 2010 11 12
Fire prevention
and pre-
suppression
22.1 27.3 24.0 24.2 5.7 10.9 12.4 23.7 22.6 20.2 21.2 22.7 21.9
Fire suppression
67.9 58.9 68.7 65.9 68.9 n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a.
Goods and
services
173.7 116.7 156.6 650.6 141.3 486.7 109.2 46.8 25.2 125.5 191.0 106.0 158.2
Post fire
recovery
68.6 45.3 65.2 286.1 57.1 213.9 36.3 9.8 5.5 24.1 46.1 20.0 48.1
**Total
social cost
264.4 189.3 245.8 960.9 204.1 700.6 145.5 84.3 57.3 173.6 237.1 126.0 206.3
*Based on ISA (2005) plus unpublished official (ICNF) data (2005-2012)
**Excluding fire suppression
Forest area decreased 4.6% between 1995 and 2010 corresponding to a net decrease of 0.3% year
-1
,
or 10
4
ha year
-1
(ICNF 2013). This may come as a surprise considering the very high incidence of
wildfire and first of all it is explained by the contribution of shrubland and grassland to total area
burned (Table 4.2). Also, the dominant forest types are fire-resilient, as eucalypts and oaks resprout
(Catry et al. 2010) and maritime pine regenerates profusely after fire (Fernandes and Rigolot 2007).
Nevertheless, the area occupied by maritime pine diminished by 263 x 10
3
ha between the forest
inventories of 1995 and 2010, while eucalypt expanded its distribution by 81 x 10
3
ha (ICNF 2013).
The decrease in maritime pine area is in fact the major driver of the observed decrease in forest
surface. Although sanitary cuts to control the spread of the pine wilt nematode are also involved,
wildfire is the main factor behind the decline of maritime pine: fire return intervals <20 years
compromise regeneration because the species is unable to reach maturity and produce seed (Fernandes
and Rigolot 2007). The expansion of eucalypts is also partially explained by wildfire incidence, which
encourages forest owners to replace pine with a short-rotation species, hence relatively compatible
with frequent fire (Pereira et al. 2006).
3. The structural causes of fire
The causes of forest fires are manifold and in Portugal, as elsewhere in Europe, are essentially
anthropogenic. False alarms and rekindles represent 8.4% of the total number of ignitions (2001-2012)
that were successfully investigated, i.e. a cause was identified. Negligence (including accidents),
arson, and lightning were the cause of respectively 65.4, 33.4 and 1.2% of the remaining ignitions;
approximately half of the negligent fires are tied to land-management practices, namely pasture
renewal. Ignition is however just one of the switches involved in fire activity, the others being biomass
(potential fuel), availability to burn (a function of moisture, as determined by recent weather and
drought) and the likelihood of fire spread in response to weather conditions (Bradstock 2010).
Apparent fire causes and the consequent fire activity and consequences are then the outcome of deeper
causes. A cause-effect analysis perceives human-caused ignitions as the effect of causes or structural
problems of rural landscapes, translated in the form of traditional fire uses in the new context of a
highly flammable landscape.
Structural causes that result in wildfires explain the fire regime dynamics. Structural causes are then
the problem that fire management policies should actually address. The modern fire regime in the
northern part of the Mediterranean Basin reflects modifications in land use conducive to less-
intensively used and more flammable landscapes (Moreira et al. 2011); climatic changes that increase
fire weather severity (Moriondo et al. 2006); and fire suppression policies that decreased the burned
area (e.g. Moreno et al. 2013), although such effect is counteracted by fuel accumulation and is not
7
expected to extend into the future (Collins et al. 2013). Traditional fire use still persists in some
mountain regions further complicating fire management under global change (Fernandes et al. 2013).
3.1 Weather and climate
Fire activity is closely tied to weather and drought conditions. Carvalho et al. (2008) explained
more than 80% of the variability in monthly burned area in Portugal through the Canadian Fire
Weather Index system, a function of ambient temperature, relative humidity, wind speed and
antecedent precipitation (Van Wagner 1987). Most (80%) of the surface burnt arises from fires
occurring on just 10% of summer days (Pereira et al. 2005). The burned area, the representativeness of
large fires and fire size all increase as fire weather becomes more severe (Table 4.4). In Portugal the
two upper fire danger classes (Very High and Extreme) defined by thresholds in the Canadian Fire
Weather Index – concentrate most of the fire activity. Days with extreme fire danger are 0.4 to 19.8%
of the total number of days, depending on region, but lower ignition density and limited fuel
availability tend to decrease fire activity in southern Portugal where fire danger is consistently higher.
Table 4.4 Fire activity in Portugal (2001-2010) in relation to fire danger rating
Fire
danger
Class
fires
Burned
area (%)
Rekindles
Fires
>1 ha
Fires
>100 ha
Fire size (ha)
(%)
Forest
Total (%) (%) (%) 99th
perc.
Max.
Low 13.3 1.2 2.1 15.7 1.5 0.08 11.0 642
Moderate
18.1 2.5 3.1 14.2 2.7 0.09 11.7 1742
High 19.5 4.3 5.0 14.4 4.0 0.19 15.0 2975
Very
high
31.4 25.0 26.7 19.0 5.3 0.63 57.0
16770
Extreme 17.8 67.1 63.1 22.3 6.3 1.99
297.3
22190
Climate change scenarios for the 21st century predict that annual rainfall in Portugal will be
reduced by 20 to 40% of the current amount due to a shorter wet season, and that annual and summer
temperatures will increase, especially inland (Miranda et al. 2002). Soil water deficit, soil degradation
and desertification, and fire danger are all expected to increase, and climate change will directly
(through environmental stress) and indirectly (through changed fire regime and higher biotic-induced
tree mortality) contribute to modify the distribution patterns of forest ecosystems; sclerophylous oak
forest types will move northwards and forest cover will decrease in the south (Pereira et al. 2002).
More extended dry and warm summers in the Mediterranean Basin indicates longer fire seasons,
concomitant with more frequent and severe weather events leading to higher-intensity, larger and more
impacting wildfires (Moriondo et al. 2006). Extrapolation into the future of current weather-fire
relationships (e.g. Carvalho et al. 2010; Pereira et al. 2013) is however fraught with uncertainty, due to
insufficient understanding of processes (Macias Fauria et al. 2011) and disregard for the simultaneous
changes in vegetation, ignition sources and fire management (Hessl 2011; Fernandes 2013). The
response of fire activity to weather and climate is mediated by vegetation (Pausas and Paula 2012)
hence the frequency and severity of future fires will be affected by the degree of change in ecosystem
productivity. Fire activity may in fact decline in parts of southern Europe due to fire-spread limitations
imposed by fuels (Krawchuk et al. 2009).
3.2 Socioeconomic factors
As Costa et al. (2011) noted, weather is the trigger for relevant fire activity in Portugal but
socioeconomic and landscape variables induce important interregional variability. Changes in the
Portuguese society from the 1950s to the 1970s led to a half-century period characterized by the
unsustainable management of forest resources. Rural abandonment and the decrease in biomass use
8
(e.g. due to the transition to other energy sources) generated non- or sub-managed landscapes in
conflict with the society (Pinho 2012). The former mosaic of agriculture, grazed land and forest
patches collapsed and was replaced by continuous and highly flammable wildlands. While an
impressive afforestation effort was carried out in public and common land during the 20
th
century, it
was not followed by proper forest management, sylviculture and fuel-hazard reduction, especially after
the 1970s. The careless use of fire for various land management purposes persists and the lack of
awareness of the fire risk is generalized among periurban populations. Particularly vulnerable
situations arise when wildlands meet expanding urban perimeters or isolated small villages and human
life and property are threatened, configuring a civil protection problem.
Private ownership of land extends over 94.3% of Portugal. Forest properties are largely (76%)
inherited, only one third of the proprietors holds more than 5 ha of land (denoting a barrier to effective
forest management), and 25% of the land is abandoned or lacking management (Beires et al. 2013).
This apparent abandonment can be qualified as passive management and is in fact a rational option
justified by the low expectancy of obtaining an economic return from investment. In this context, legal
retaliation (e.g. through fines) against forest owners and generalized fuel-hazard reduction are neither
possible nor advisable from both the economic and ecological points of view.
3.3 Political and institutional factors
Exacerbation of the wildfire problem was contributed to by frequent institutional changes and loss
of the State capacity to intervene, without a private sector counterpart. Prior to the wildfire crises of
2003 and 2005 fire management policies have been markedly reactive, inconsistent and short-sighted.
Fire management consecutively reinforced the resources for fire suppression rather than addressing the
structural causes, namely land ownership structure, forest and land management, the State authority,
social cohesion, and regulation of the agricultural and forest and soil markets (ISA 2005).
Political response to fire incidence in Portugal is blatantly interventionist. A plethora of command
and control instruments (legislation, regulation, planning) have been introduced over the years,
together with financial instruments. Those instruments are modified and updated continuously and
constantly, often with potentially conflictive outcomes. The result is confusion, insufficient knowledge
of regulations and, more significantly, the inability to follow a consistent path towards effective
results. Fire-related responsibilities and competencies are dispersed across various governmental
ministries (Agriculture, Environment, Economy, Interior) and agencies, which only worsens the
problem.
The Portuguese forest service (PFS) went through copious and frequent changes in the last four
decades, which clearly signals lack of understanding of its role by policy and decision makers. We will
now identify the structural modifications of the PFS with a potentially relevant impact on the
effectiveness of fire management in Portugal. The law enforcement capacity of forest rangers
diminished after the 1974 revolution. Fire suppression was transferred from the PFS to the national
fire fighting service (i.e. volunteer fire fighting brigades) in 1980-81. The PFS vertical structure was
dismantled and regionalized in 1996, which was recognized as a failure and in 2004 was reverted. The
forest rangers were then absorbed by GNR, a police corps within the dependency of the Ministry of
the Interior, which definitely ended their law enforcement duties in the forests managed or co-
managed by the PFS. GNR also took hold of fire detection through the management of the national
network of fire lookout towers. Restructuration programs of the Portuguese public administration
further withered the PFS human resources allocated to public and communal land management. The
current national fire system (DFCI) and fire plan were established in 2006, following the catastrophic
fire years of 2003 and 2005. The PFS organization is highly volatile since 2003, with consecutive
organic restructuration and changes in objectives and strategies that disturb functioning and
compromise the definition and attainment of long-term goals.
3.4 Contemporary instability in forest and fire management policies
The instability inherent to endless changes in the legal and institutional frameworks is recognized as
a weak feature of the DFCI system (Silva et al. 2008). The amount of national-level strategic
documents produced (six from 2003 to 2006) is by itself a symptom of instability (Table 4.5).
9
Table 4.5 National-level Portuguese forest strategies and plans (1996-2013)
Year Plan
1996 Forest Policy Bases Law
1999 Portuguese Forest Sustainable Development Plan
2003 Action Plan for the Forest Sector
2003 Forest Sector Structural Reform
2005 Operational Plan of Forest Fires Prevention and Suppression
2006 National Plan of Forest Defence Against Fires (2006-2018)
2006 National Forest Strategy
Instability is also manifested in the national discussion fora (five different councils from 2003 to
2012) and in the national parliament, which in 10 years produced 11 recommendations to the
government on fire management policies. DFCI planning at the regional and local levels is also
haphazard. Regional forest management plans were approved in 2006 and 2007 but were partially
deferred in 2011. Similarly, regional DFCI plans approved in 2009 and 2010 were never implemented.
Municipality-based DFCI was established in 2004 under PFS supervision (until 2009), moving away
from the previous focus on forest owners associations, and producing the first plans in 2007.
Awareness and education programs for the population have been intermittent. The approach that
initiated in 2005 and distinguished between audiences (the general public, students, and rural
population) was interrupted shortly after. As of 2007 the mass-media slogan “Portugal without fires
depends on us all” was adopted and is still in force.
On the operational side, the hand crew fire fighters program (PSF) appeared in 1999 as a primary
but unstable policy instrument to decrease fuel hazard and value forestry assets, as it was the subject of
three legislative modifications in 10 years. Still on the operational side, initiatives to expand fuel
management (GeFoCo, 2006-2009) and improve fire suppression (GAUF, since 2007) through
specialized forest technicians were short-lived or did not attain critical mass. Other ephemeral
initiatives regularly (dis)appear, e.g. in relation to the army involvement, public awareness, youth
volunteer programs, aerial monitoring or automatic fire detection. Likewise, funding is highly
unstable. An eco tax on oil-derived fuels was created in 2004 to fund fire prevention and fuel
management (FFP). In 10 years FFP regulations were changed five times and 15 normatives were
issued. Finally, national-level coordination of DFCI has been assigned to five distinct agencies in the
framework of six different organic laws in 10 years, under the responsibility of five ministers, seven
secretaries of state and eight general-directors.
4. Fire management strategy and planning
Wider-scope national forestry strategies and plans (Table 4.5) outline the current Portuguese fire
management policy. High fire incidence is a significant perceived risk, i.e. the observable consequence
of a real risk, and its mitigation is an essential component of the national forest strategy. The DFCI
policy is operationalized through a national plan (PNDFCI) that seeks to minimize the risk of fire and
follows the directives of the National Forest Strategy (EFN). The EFN emphasizes improved
(sustainable and professional) forest management, critical to decrease fire risk, and three fire-
mitigation actions within the so-called “structural fire prevention”: fuel management through grazing,
namely to maintain strategically-placed regional networks of fuel breaks in a cost-effective way; the
sustainable use of biomass for energy; and prescribed burning as a cost-effective technique in synergy
with grazing.
10
The PNDFCI defines the fire management strategy and goals and determines its objectives,
priorities and activities. Three pillars of action are considered, each coordinated by a distinct agency:
structural prevention (PFS); vigilance, fire detection and law enforcement (GNR); and fire suppression
(ANPC, the national civil protection authority). The PNDFCI comprises five strategic axis of
intervention:
1. Increased fire resiliency, essentially through the expansion of actively managed forest and fuel
treatments.
2. Decreased fire incidence, by promoting forest and environmental education, improving the
determination of fire causes, and reinforcing the capacities of dissuasion and law enforcement.
3. Increased fire-suppression effectiveness, through better coordination of pre-suppression
activities; better integration of fire fighting teams and agents from distinct origins; improved fire-
suppression planning procedures at national level; improved integration of planning and decision-
support tools.
4. Ecosystems restoration, with recommendations to establish a specific post fire recovery program,
evaluate post fire rehabilitation work, and assess the potential of burned areas to recover.
5. Adoption of a functional and effective organic structure, improving agency organization to assure
adequate response and consolidating the organization and interagency liaison at the municipal,
regional and national levels.
The PNDFCI considers two time periods (2006-2012 and 2013-2018) and sets annual quantitative
goals for each (which is quite disputable) namely regarding the numbers of fires >1 and >1000 ha,
burnt area, initial attack response, the number of fires active during more than 24 hours, and the
percentage of rekindles. The annual area burnt goal for 2006-2012 is quite modest (<10
5
ha, the long-
term mean), probably reflecting the impact that the extreme years of 2003 and 2005 had, but it was not
reached in 2010, 2012 and 2013; the 2013-2018 goal is to restrict burned forest to <0.8% of its
occupation. On the contrary, the goal of eliminating fires >1000 ha is unrealistic.
The DFCI national system defines the structural measures and operational activities regarding forest
and communities protection from fire. At the planning level the system foresees consistency in
policies, instruments and measures across spatial scales, defining fora for strategic planning and
coordination among agencies locally and regionally. Regarding the vegetation component of fire
management, an infrastructure (forest defense network) is defined and implemented through
strategically located fuel breaks and fuel treatment mosaics to increase the likelihood of suppressing
large fires. Specific legislation has been created to accommodate the use of fire in fuel management
and in fire suppression operations. The DFCI system finally defines the responsibilities of those
involved in fire pre-suppression (patrolling, fire detection, law enforcement) and fire control and
extinction, and regulates post fire restoration.
5 Towards improved fire management
Success of the DFCI system is dependent on the determination and persistence to precisely follow
what has been established for each PNDFCI axis, at least until 2018, its term. The puzzle of fire
management activities will achieve long-term sustainable results if its individual components (ignition
control, structural prevention, pre-suppression, suppression) function properly and meet the overall
expectations. The DFCI system suffers however from a crucial deficiency, the absence of a
coordinating agency managing a global budget. The main government function is to guarantee the
integrity of fire management activities, and proper system coordination is a pre-requisite for its
maintenance, evolution, and development of an institutional culture able to accept and assimilate
additional knowledge. Several opportunities to improve the DFCI system performance can be
identified and will be described.
The need for a functional and efficient organic structure deserves special attention. Resources
exclusively dedicated to fire management and with operational capacity at the regional level should be
available in the PFS. Changes in human behaviour and better forest management take time. It is then
crucial that the agencies involved keep on track with the PNDFCI course of action. As previously
mentioned, there ought to be a single political interlocutor for the PNDFCI and the DFCI system.
11
Implementation of the PNDFCI emphasises the local (municipal) scale, whose technicians work
independently and, with the demise of the PFS, fulfil tasks beyond what was initially conceived.
Critical mass and better focus would be achieved by teamwork and concentration of efforts.
Accreditation by professional associations and orders offers an opportunity to increase the technical
proficiency and work quality of those involved in fire management, namely regarding highly
specialized tasks (e.g. fire use). Skills in wildfire analysis and advanced spatial planning with fire
behaviour and fire growth software are decisive and are currently absent or underdeveloped. These
technical solutions allow for the passive management option and meet the forest owners’ expectation
of minimizing investment as the logical outcome of the perceived fire risk.
The PSF hand crews program is the main State-supported structure regarding hazard-reduction fuel
treatments. However, the PSF program requires renewal and reinforcement. While an increase in the
number of crews is a PNDFCI goal, other improvements are apparent. Larger, fully professional,
better-trained and equipped crews are needed for better performance and higher effectiveness, namely
the amount of fuel-reduced area.
The responsible and skilled use of fire would benefit from a national fire use program, integrating
its traditional use in land management, namely for grazing uses; prescribed burning to reduce
hazardous fuels or for other forest management purposes; suppression fire as a fire-fighting tool; and
the management of unplanned fire. This would allow a framework and articulation for the use of fire
by rural population and the professional use of fire in either land management or wildfire
management. The scale and technical requirements of a program of this nature requires adequate
knowledge and skills and training on integrated fire management principles and methods, from policy
and decision makers to fire, forest and land managers.
Vegetation is regularly controlled along several linear infrastructures in the territory (electricity
networks, gas pipelines, railways, roads). Integration of these structures in fuel-treatment planning
would expand the ability to challenge landscape fire spread. Other activities (e.g. nature tourism,
establishment of ecological corridors, new grazing modalities, renewable energies production) can be
part of the multifunctional valorisation of forests and wildlands and add to their preservation,
addressing rural abandonment, the real cause of territorial unbalances.
Fire management policies in fire-prone ecosystems evolve with the development of forest resources
management (Lotan 1979). The attempt to totally exclude fire follows indifference and the generalized
use of fire, and tends to be replaced by the reintroduction of fire. Fire management in its full
expression is associated to multiple and competitive forest uses and considers the economic and
ecological implications of fire. Fire exclusion policies implement aggressive fire suppression under
rigid standards to minimize burned area and damage, regardless of the assets under threat or the
conditions under which a fire spreads (Lotan 1979; Fischer 1980). Fire exclusion can apparently
succeed on the short-term, but the ensuing fuel accumulation can, depending on vegetation type, foster
larger and more severe fires in the future (Pyne 2001; Stephens and Ruth 2005) the fire extinction
paradox or fire fighting trap (Collins et al. 2013). The Galicia region of NW Spain offers a textbook
example of the consequences of such unbalanced fire policies: lack of fuel treatments, land
abandonment and high ignition density combined with drought in 2006 to override the deceptive fire
control improvements brought by the previous decade (Fernandes 2008).
An advanced fire management policy should be guided by land and forest management objectives;
integrate all the available biological, ecological, physical and technological fire-related information to
achieve the management goals; involve fire in land management planning right from the start of the
process; and consider different strategies to accommodate different land management objectives
through zoning (Egging and Barney 1979). In line with these early recommendations, the holistic
concept of integrated fire management (Myers 2006) systematically evaluates and balances the risk of
fire with its benefits by considering the multidimensional context. Integrated fire management
translates into a consistent set of complementary strategies that seek to minimize the net social cost of
fires, respectively fuel management with prescribed burning to decrease wildfire risk and severity;
reduction of the number of unplanned fires and integration of the traditional use of fire; and decreasing
wildfire size through the use of fire in suppression (Rego et al. 2010).
12
6 Synthesis and conclusion
To be effective, the DFCI system should consider and incorporate three interdependent key points:
good governance, risk-oriented planning, and funding instruments.
The need for good governance has been stressed in the 1996 and 2006 strategic guidelines for
forests in Portugal. Partnerships between different agents, adoption of common programs and shared
responsibilities between sectors are extremely important to guarantee the success and longevity of a
project. Good governance implies that governments and agencies should restrain from impulsive,
intermittent, ad hoc and out of context actions and decisions. Detached initiatives waste resources and
deviate agencies from their core functions. Continuity and resolution in policies and maturity and
ethics in policy-making are crucial.
Good governance also depends of the intervening agencies and actors, assuring that their roles in
the DFCI system are balanced. In Portugal this equilibrium is compromised by three problems,
respectively agency instability, lack of leadership in the form of overall system coordination, and poor
understanding of the interdependence of the fire prevention, fire pre-suppression and fire suppression
axis. This latter problem impacts severely on the allocation of resources between axes, which as
previously mentioned is quite unbalanced.
Good governance should go along with an adequately delineated program of action that takes into
account the existing risks. The EFN identifies risks that are either real or perceived and are connected.
The former (strategic, market, financial, political, operational, social risks) clearly determine the
perceived risk. Mitigation of the real risks, e.g. through better forest management, will decrease the
wildfire perceived risk. Decreased fire risk - e.g. through carefully designed fuel treatments capable to
impede large fire growth through more effective fire suppression - on the other hand contributes to
restore confidence on the forest sector, attracting more investment and improving forest management.
The DFCI system needs adequate funding support, but the PNDFCI is devoid of an intrinsic budget.
Absence of a joint vision of the available financial resources can by itself compromise governance and
planning. The DFCI system does not clarify how funding is partitioned by the agencies involved, and
does not identify the supporting funding instruments (national or European, public or private). In fact,
the total cost of the DFCI system is not precisely known, which precludes the consistent allocation of
resources between fire management axes. Extreme (or merely above the average) fire years tend to
strengthen the investment in fire suppression and reinforce the fire-fighting trap. Attaining a gradual
increase in the prevention-to-suppression costs ratio towards equilibrium does not imply the automatic
loss of fire fighting resources. Investment in prevention is initially required, but the resulting savings
in fire suppression costs (due to non-utilized resources) would be transferred to fire prevention at a
later stage.
The national DFCI system must follow a single pathway, mutualistic, and where cooperation and
complementarity between agencies is favoured by positive and synergistic interactions leading to fire-
safe communities and sustainable forest ecosystems.
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15
FIGURE CAPTIONS
Fig. 4.1 Cumulative area burned and fire recurrence (number of times burnt) in Portugal (1975-2012).
Most of the unburnt surface has one or more of these features: urban, agricultural or agroforestry land
use; relatively low population density; flat or undulated terrain; relatively low rainfall
Fig. 4.2 Burned area in Portugal (1980-2012). A cubic spline regression was fitted to data to indicate
the temporal trend
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Thesis
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Portugal has been experiencing a seasonal problem of rural fires for decades. The most striking episode occurred in 2017 when there was a total loss of 117 human lives, reaching historical values of burned area of 533710 hectares and millions of euros in direct and indirect damages. The impact of this catastrophe on Portuguese society was enormous, leading to the need for the State to move forward with a series of policies, including the creation of several programs such as Aldeia Segura, Pessoas Seguras, among many others. Beside that, after five years, much remains to be done, in terms of planning and land use, the regeneration of burned areas, the recovery of housing, and forest management. We know that this problem is directly related to the Mediterranean climate, the abandonment of rural areas, the forest areas that characterize the country, so the recurrence of these extreme phenomena will be increasing in the future. Thus, the present work intends to idealize a Websig that allows to support the reduction of the risk of fire at the local level, allowing not only municipal technicians and other institutions that are usually in the theaters of operations easier access to information, but also making that same information available to populations so that they better understand the risk.
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This paper explores the role of landscape planning as a tool for rural fire prevention. It presents a methodology for a fire resilient and sustainable landscape model (FIRELAN) that articulates the ecological and cultural components in a suitable and multifunction land-use plan. FIRELAN is a conceptual and ecologically based model that recognizes river basin’ land morphology, microclimate, and species combustibility as the fundamental factors that determine fire behavior and landscape resilience, along with the ecological network (EN) for achieving ecological sustainability of the landscape. The model is constituted by the FIRELAN Network and the Complementary Areas. This network ensures the effectiveness of discontinuities in the landscape with less combustible land-uses. It also functions as a fire-retardant technique and protection of wildland-urban interface (WUI). This model is applied to municipalities from Portugal's center region, a simplified landscape severely damaged by recurrent rural fires. The results show that land-use and tree species composition should change drastically, whereas about 72% of the case study needs transformation actions. This requires a significant increase of native or archaeophytes species, agricultural areas, landscape discontinuities and the restoration of biodiversity in Natura 2000 areas. The EN components are 79% of the FIRELAN N area, whose implementation ensures soil and water conservation, biodiversity, and habitats. This paper contributes to the discussion of the Portuguese rural fires planning framework, highlighting the role of this model implementation towards a new landscape by giving explicit indications of adequate land-uses in rural areas. The FIRELAN model can be replicated in any situation.
Chapter
The recent advent of machine learning as a transforming technology has sparked fears about human inability to comprehend the rational of gradually more complex approaches. Interpretable Machine Learning (IML) was triggered by such concerns, with the purpose of enabling different actors to grasp the application scenarios, including trustworthiness and decision support in highly regulated sectors as those related to health and public services. YOLO (You Only Look Once) models, as other deep Convolutional Neural Network (CNN) approaches, have recently shown remarkable performance in several tasks dealing with object detection. However, interpretability of these models is still an open issue. Therefore, in this work we extend the LIME (Local Interpretable Model-agnostic Explanations) framework to be used with YOLO models. The main contribution is a public add-on to LIME that can effectively improve YOLO interpretability. Results on complex images show the potential improvement.KeywordsInterpretable machine learningExplainable Artificial IntelligenceDeep learningYOLOLIME
Article
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Wildfires are a serious threat to ecosystems and human. In Portugal, during 2017, a catastrophic fire season burned more than 500 000 hectares and caused the death of more than 100 people. Previous studies have shown that hot and dry fuel conditions promoted widespread propagation of wildfires. However, burned area (BA) and mega-fires, such as the 2017 ones, depend not just on favourable meteorological conditions, but also on fuel accumulation and dryness. In this study, we will assess the influence of spring meteorological conditions on fire season BA, through their effects on fuel accumulation and dryness. Using satellite-based data, we show that the association of higher temperatures and water availability in spring can increase the risk of summer wildfires propagation, flammability and intensity through their influence on vegetation gross productivity. This study highlights the important role of fuel accumulation during the growing season in fire-prone regions like Portugal. Our results imply that fuel management may be an effective way to mitigate extreme fire seasons associated with warmer and drier conditions in the future.
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Com a necessidade de impulsionar a mobilização da terra e a gestão rural sustentada urge dinamizar o cadastro. Os preceitos legais que enquadram a posse, o uso e a propriedade da terra evidenciam uma “Rede Territorial do Domínio Público” e o seu reverso a “Malha Cadastral das Zonas de Propriedade Registável cuja delimitação permitirá acelerar aquele, a harmonização registral e a identificação das terras abandonadas e sem dono. Propõe-se para estas um fundo público autónomo. Revendo o território e o processo cadastral sugerem-se aperfeiçoamentos. Na questão fiscal dos prédios rústicos, defende-se o princípio da “gestão rural ou pagador” e a organização dos serviços do território, como meio dinamizar o registo e comércio local das terras, visando a expansão das explorações.
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RESUMO Os Serviços Florestais portugueses mantiveram desde a sua criação um particular interesse no conhecimento da flora e das formações vegetais espontâneas, base para uma melhor definição quer das estratégias para o desenvolvimento florestal do país, quer das opções de gestão para cada mata a seu cargo. O presente artigo constitui uma primeira abordagem à história e atividade desses Serviços no âmbito da botânica sistemática, da fitossociologia e da gestão e conservação dos recursos florísticos do Continente, desde o seu surgimento no início do Século XIX até aos nossos dias. ABSTRACT Since its foundation, the Portuguese Forest Service maintained a particular interest in the study of flora and natural vegetation, as a basis to better define the strategies for developing the country's forest or to improve the management in the public forests. This article presents a first approach to the history and activity of this state agency in the fields of systematic botany, phytosociology and conservation of forest resources, from its establishment in the early nineteenth century to the present day.
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Fire is a global process fecting both the biosphere and the atmosphere.As a result, measuring rates of change in wildland fire and understanding the mechanisms responsible for such changes are important research goals. A large body of modeling studies projects increases in wildfire activity in future decades, but few empirical studies have documented change in modern fire regimes. Identifying generalizable pathways through which climate change may alter fire regimes is a critical next step for understanding, measuring, and modeling fire under a changing climate. In this progress report, I review recent model-, empirical-, and fire history-based studies of fire and climate change and propose three pathways along which fire regimes might respond to climate change:changes in fuel condition, fuel volume, and ignitions.Model- and empirical-based studies have largely focused on changes in fuel condition with some models projecting up to 50% increases in area burned under a 2 x CO2 climate. Fire history data derived from tree-rings, sediment charcoal, and soil charcoal have helped identify past trajectories of change in fire regimes and can point to possible future conditions. However, most fire history research has focused on changes in area burned and fire frequency. Changes in fire severity may be equally important for the earth system and require further attention. Critical research needs include next generation dynamic vegetation models (DGVMs) that consider changes in vegetation alongside changes in human activities and long fire history records from a variety of vegetation types suitable for validating these DGVMs.
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Wildfires are a major problem in Portugal. Since 1980 an area equivalent to 3/5 of the forested surface has burned. The aim of the study was to assess the potential impact of regional climate change on wildfires in Portugal using an appropriate Burnt Area Model (BAM). Based on multiple regression analysis, the model was able to estimate the decimal logarithm of the monthly burnt areas in July and August using the Daily Severe Rating as a predictor in the pre-fire season (May and June) and the fire season (July and August). The BAM, which was able to explain 63% of the total observed variance from the 1980-2011 period, was then fed with simulated data by a Global Climate Model (GCM) for the present climate and for two 30 yr periods (2051-2080 and 2071-2100) of future IPCC emission scenario B1. Comparison analysis between the logarithm of burnt area in July and August under present and future climate conditions shows an increase in the mean values of 7 and 11% for the first and second 30 yr periods, respectively, and a decrease of 32% in the SD for the first (2051-2080) period but no distinction between the observed and the simulated values for the last (2071-2100) period. Obtained estimates with the developed approach consistently point towards an increasing risk of fire under future climate conditions, and thus an increasing likelihood of much larger burnt areas.
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Natural conditions favor fires in the American West. In this Science and Society essay, Pyne describes three major trends in the state of fires there. One is the advent of industrial fire, a shift from burning living to fossil biomass. Another is the imperial story of how the West became public land. The last is a national narrative, the peculiar choices the United States has made over the past century about how to cope with fire. In imagining the future of fire, all three trends should be considered. The likelihood is that the crisis de jour--fires racing through landscapes in which houses mingle with wild lands--will pass within 10 years.
Article
Fire regimes play an important role in ecosystems and climate change, affecting the structure and composition of vegetation and influencing carbon dioxide (CO2) emissions. Analyses of historical fire regimes have indicated that in many ecosystems, fire regime changes are linked to environmental and climatic changes, but these studies have often been both spatially and temporally limited. To determine whether there have been changes in the fire regime in Spain, we used a statistical change point approach to analyse the number of fires and the burned area since fire statistics were first recorded in 1968 for three pyrologically homogeneous regions over two fire seasons (vegetative season = May–November, non-vegetative season = December–April). Then, to assess the possible driving forces behind these changes, we related the significant change points for the number of fires and burned area to climate, land use and fire management variables. For the vegetative season, we observed upward and downward change points in all three regions. In the non-vegetative season, only upward change points were detected in all three regions, whereas downward changes only occurred in the Mediterranean region. Our analyses suggest that the fire regime changes have been driven by climate and land use and, more recently, have also been influenced by fire suppression policies. Our results may contribute to enhance fire management and future studies of fire ecology and climate change.
Article
Aim: To understand how vegetation mediates the interplay between fire and climate. Specifically, we predict that neither the switching of climatic conditions to high flammability nor the sensitivity of fire to such conditions are universal, but rather depend on fuel (vegetation) structure, which in turn changes with productivity. Location: An aridity/productivity gradient on the Iberian Peninsula (Mediterranean Basin). Methods: We defined 13 regions distributed along an aridity gradient, which thus differ in productivity and fuel structure. We then assessed the changes in the temporal fire—climate relationship across regions. Specifically, for each region we estimated three variables: the aridity level for switching to flammable conditions (i.e. climatic conditions conducive to fire), the frequency of these flammable conditions and the area burnt under such conditions. These variables were then related to regional aridity and fuel structure indicators. Results: In mediterranean ecosystems, the aridity level for switching to flammable conditions increased along the aridity gradient. Differences in fire activity between regions were not explained by the frequency of flammable conditions but by the sensitivity of fire to such conditions, which was higher in wetter and more productive regions. Main conclusions: Under mediterranean climatic conditions, fuel structure is more relevant in driving fire activity than the frequency of climatic conditions conducive to fire. At a global scale, fuel also drives the fire—climate relationship because it determines the climatic (aridity) threshold for switching to flammable conditions. Our results emphasize the role of landscape structure in shaping current and future fire—climate relationships at a regional scale, and suggest that future changes in the fire regime (i.e. under global warming) might be different from what it is predicted by climate alone.