Agriculture Reference
In-Depth Information
be as much a response to winter channel-scouring damage as to fire. Seedling
recruitment is not tied to fire but rather to the annual flooding cycle.
Marshes, wetlands and coastal lagoons used to be frequent all along the
Mediterranean coast in many countries of the region. In the past many were drained
for agricultural purposes and more recently for building houses and tourist resorts.
Remnants of these ecosystems are still very important biodiversity spots and for the
ecosystem functions they provide such as maintaining the local water cycle (Milla´ n
2002
). Coastal dunes, with
Pinus pinea
and
Juniperus
species, have also been
dramatically reduced. Although under the right conditions these ecosystems may
be flammable, they do not regularly burn.
Fire Management
Fire has been used as a management tool for thousands of years (Pausas & Keeley
2009
). Shepherds around the Mediterranean Basin have traditionally burned
shrublands and grasslands to promote palatable plants and stimulate growth.
Indeed, fire has often been considered as necessary to shepherding as ploughing
is to farming. Even in some deciduous woodlands, leaf-litter fires were lit to
improve understory pastures. However, at least in mediterranean Europe, the
current cultural framework suggests that dense forests are the best possible
vegetation for any landscape, and that shrublands are the product of degraded
forests. In this framework fires are viewed by land managers and society in general
as bad, and land management is largely focused on reducing fires and increasing
forests (Seijo
2009
). This is mainly a cultural parading, not always based on
scientific grounds, and is strongly influenced by the northern European forest
tradition. The management of MTC ecosystems requires a paradigm shift,
whereby ecosystems are viewed in their ecological, historical and biogeographical
context and where fire regimes are an important ecosystem process (Pausas &
Vallejo
2008
).
The consequences of this current land management framework, together with
the recent socio-economic changes, is that fire use has declined and most places it
has been outlawed. This has produced changes in landscape-level fuel loads and
a shift from frequent light fires to infrequent high-intensity wildfires in some
mountain coniferous forests. Indeed, surface fires are currently very rare in the
Mediterranean Basin whereas they were probably common in the past in moun-
tain coniferous forests (Vega
2000
; Fule´
et al.
2008
). The combination of the
abandonment of fire as a management tool, the reduction of grazing, interest in
maximizing wood production, and efficient fire-prevention and fire-suppression
measures, have worked in concert to decrease fire frequency and increase fuels.
Thus, when a fire occurs in these ecosystems, it is in the form of a crown fire.
Most mountain coniferous trees do not have traits to regenerate after a crown
fire, and thus these fires are threatening forest structure and biodiversity. There
is increasing evidence that periodic fires or grazing would help to maintain
