The Portuguese forest

Transcription

1 The Portuguese forest

2 The Portuguese forest represents 3.5 millions ha of all national territory (2005) Chart legend % Species 23 Eucalyptus sp. 0.1 Acacia sp. 3 Other hardwoods 27 Pinus pinaster 4 Pinus pinea 1 Other pine trees 23 Quercus suber 13 Quercus rotundifolia 5 Other Quercus 1 Chestnut trees Sorce:

3 The Oak Forest Native Forest species examples In Portugal, the oak forest represents 41% of the all forested area and includes several species Quercus suber L. Quercus rotundifolia Lam. Quercus faginea Lam. Quercus pyrenaica Willd. Quercus coccifera L. Quercus robur L. Quercus lusitanica Lam. Quercus canariensis Willd. Specimens from the LISU Herbarium at MNHNC Botanic Garden, Portugal

4 The Cork oak and Holm Oak woodlands The Cork and Holm Oak woodlands cover approximately 1.2 million ha from the central part of the country, a sparsely populated region called Alentejo with one of the country's (and the world s) largest agricultural exports of cork, to the Algarve on the extreme south of the country. Some non negligible areas can also be included, in the center-east and northeast region (see maps below). As such, the products from these oak savanna-like woodlands are the acorn (from Holm oak), herbaceous forage and specific cattle breeds such as the black iberian pig and the gravanesa cow. Acorn and cork from Cork oak Other commercial benefits arrive from charcoal production, cereal crop cultivation, honey production and wild mushroom picking. Aromatic/medicinal plants are used for industrial tannins and resin ladano production.

5 Quercus rotundifoliaand Quercus suberdistribution in Portugal. Adapted from the National Forest Authority data. March Cork oak (Quercus suber) Holm oak (Quercus rotundifolia)

6 In Portugal, the industrial harvest of cork began on the 19th century. In that period selective thinning and low density cultivation techniques were introduced so that the soil could be used for farming. At the end of the 19th century, the Portuguese cork oak forests were considered the most well managed in the world. Oaks from this ecosystem can grow up to a height of 82 feet and live up to three hundred years, continuously serving the local populations, who periodically strip the bark of the Cork oak. This unique bark (cork) protects the tree both from cold winters and from fires in the dry summers, climate characteristics of the Mediterranean regions. Moreover, Cork oaktrees work via biological processes to modify soil properties in the ecosystem. They enrich the soil in nutrients, attract different types of animals that promote this kind of modifications, change the soil density and porosity and thereby, increase the available stored water on the soil. Traditional methods of understory clearing have been replaced byeffective mechanized ploughing. This aimed to reduce understory fuel and thus the risk of fire exposure and damage. A typical oak savannah-like woodland landscape is illustrated below:

7 In these woodlands people use the forest and its biological products in a sustainable way to ensure the maintenance of the production. It is also the increase on oaks production that is believed to lead to a reduction in soil erosion in southern Portugal. New and old Oak forests provide a livelihood for local populations. It is well known that the present and near future of locals are dependent on the harvesting of cork, on the maintenance of high biodiversity and functional complexity of these forests. The Cork oak and Holm Oak woodlands ensure a high biodiversity of wild fauna, including approximately 53% of Portuguese species of reptiles and amphibians, more than 160 bird species, and approximately 60% of the Portuguese species of mammals. Examples of animals commonly found in these woodlands include lizards, snakes, frogs, buzzards, kites, eagles, owls, magpies, hoopoes, bee-eaters, passerines, cranes in the winter, rabbits and hares, foxes, weasels, genets, wild boars, deer and some protected species like the Cabrera's Vole or some bats and bird species.

8 At the MNHNC Botanic Garden it is possible to visit three nativeoak species: Quercus suber Quercus rotundifolia Quercus faginea

9 Scientific name: Quercus suber L. Family: Fagaceae Common name: Cork oak tree Distribution:Endemic of Southwest Europe (Portugal, southern Spain, southern France, Italy) and north Africa (Morocco, Algeria and Tunisia). Height: 10-20m The Cork oak occurred in the Tertiary Era (between the Oligocene and Miocene) during the formation of the Mediterranean basin, 60 million years ago. In Portugal, Pliocene fossils of this species were found in the Alentejo (South of Portugal). It is an evergreen tree. The Cork oak does not grow evenly during the year. In the winter, the tree canopy stay dormant. In the spring it returns to full activity extending to the end of summer. In Portugal, flowering happens between April and June and may continue for August and September. This oak produces a suberous tissue (the cork) to involve the trunk and branches. This tissue has regenerative capacity and protects the tree against biotic and abiotic factors (fire) in its natural habitat. The cork extraction is a very important economic activity in Portugal and the cork oak is legally protected.

10 Scientific name: Quercus rotundifolia Lam. Family : Fagaceae Common name: Holm oak or Holly oak Distribution : Native of Mediterranean region Habitat: Mediterranean forests Height : 27 m This oak tree flowers from April to May. The male flowers are arranged in catkins while the female flowers are arranged in panicles. The fruits are acorns (big and sweet), used for animal forage (ex. black Iberian pig). The Holm Oak is an evergreen tree, with ragged spiny-toothed leaves when young and serrated leaves in adults.

11 Scientific name: Quercus faginea Lam. Family : Fagaceae Common name: Portuguese oak Distribution: Iberian Peninsula and North Africa, Morocco and Algeria. Habitat: Common in Central and South Portugal. Height : 20m The Portuguese Oak is considered capable of recovering degraded soils and limiting erosion (facilitate the infiltration of rainfall).

12 Quercus suber Quercus rotundifolia Quercus faginea Specimens from the LISU Herbarium at MNHNC Botanic Garden, Portugal

13 Production forests Examples Industrial production forests also occupy a large area in Portugal Pinus pinaster Pinus pinea Eucalyptus sp. At the MNHNC Botanic Garden it is possible to visit: Pinus pinea L. Eucalyptus sp.

14 Scientific name: Pinus pinea L. The Stone pine at the MNHNC -Botanic Garden, in Portugal Family : Pinaceae Common name: Stone pine Distribution: Mediterranean basin Habitat: Coastline and dune regions. Height : 30m The Stone pine is native from the Portugal coast, opposing to the Eucalyptus and Maritime Pine. Use: Construction; Structures and carpentry; Furniture (Rustic and modeled); Floor coverings (parquet); Conglomerates (fibers and particles); The pinion (edible).

15 Eucalyptusat the MNHNC -Botanic Garden, in Portugal Scientific name: Eucalyptus sp. Family : Myrtaceae Distribution: Australia Habitat: Tropical forest up to subalpine habitats, until 1000m of altitude. Height : 50m Eucalyptussp. grows in several soil types with sun exposition. In Portugal, the eucalyptus was introduced around 1829 due to its characteristics amenable to industrial use, particularly the paper production. One of the biggest problems on eucalyptus production is the constant mobilization of the soil, preventing the development of sub-covered vegetal materialdue to root competition, because the fine roots that are never less than 90% of the total length of the roots. This results on an increased water uptake in the extracts of the soil. Other problem is the monoculture coverage. A good sustainable management as mixed plantations, can create environments that lead to the development of fauna and flora.

16 Scientific name: Pinus pinaster Aiton Family : Pinaceae Common name: Maritime pine Distribution: Southwest Europe and North Africa. Dispersed in the Mediterranean Basin and Atlantic coasts of the Iberian Peninsula and France. Habitat: Areas with Atlantic influence and humidity. It occurs naturally from the coastal dunes up to 1000m of altitude. Height: 40m The Maritime pine represents one of the three species that occupy the largest area in Portugal, with hectares. The Maritime pine is the main species currently supplying the Portuguese sawmill industry, carpentry, chipboard, furnitureand pulp.

17 Threats to Portugal Forest Deforestation and habitat destruction (for construction, even though some trees eg. Oaks - are legally protected) Deforestation in order to plant exotic productions (ex. Eucalyptus sp. for paper production) Fire (increasing probability with global warming) Desertification (increasing with global warming) Increase of oak illnesses and plagues due to incorrect management during cork extraction and deep ploughing Hunting and prey control (legally not authorized species) Increase of cereal crops and modification of spatio-temporal mosaic rotation (fallow lands) Increase of intensive agriculture and greenhouse farming Increase in the use of agro-chemicals Negligible efforts for the recovery and restoration of high-value biodiversity rangelands Absence of programs seeking the conversion of Eucalyptus cultivations into natural forest Absence of legislation preventing the devastation due to incorrect management practices Absence of legislation and control for mushroom and fungi harvesting and use.